The status of biological invasions and their management in South Africa in 2022 [SECOND DRAFT FOR PUBLIC COMMENT]

The S a us o Biological In asions and hei
Managemen in Sou h A ica in 2022
[SECOND DRAFT FOR PUBLIC COMMENT]
i
No e o eade 1
We a e in i ing you o submi commen s, co ec ions, and que ies on his hi d s a us epo on 2
biological in asions1. We ha e p epa ed a s anda d o m o commen ing ha you can ill in i you 3
wish, bu i you would p e e o send in you inpu s in you own o ma , please indica e he page and 4
line numbe s o which you commen e e s. Many o he echnical de ails (and da a on which he 5
epo is based like he lis o alien species) a e a ailable in he appendices and supplemen a y 6
ma e ial (links a ailable on he las page). Please also conside commen ing on hese. I you a e in a 7
posi ion o p o ide addi ional in o ma ion, we would be e y g a e ul, and will aim o ensu e all 8
con ibu o s a e app op ia ely acknowledged. I you do no wish o be named, please le us know. We 9
would like as many people and o ganisa ions o make inpu s as possible, so please pass he epo on 10
o anyone you hink migh be able o con ibu e. We will cap u e all commen s ecei ed du ing his 11
commen ing pe iod and ack how hey a e esponded o. A da abase o hese commen s and he 12
esponses will be a ailable on eques once he epo has been eleased. 13
Commen s o be sen o: IAS. epo [email protected] By: 31 July 2023 14
Fo m o commen ing: h ps:// inyu l.com/m 2mu6xz 15
This is a “second d a o public commen ”. I p esen s he indings close o how hey a e in ended o 16
be in he inal epo — he e should only be mino changes and a ew addi ional analyses, al hough 17
ins ances whe e addi ional analyses a e planned o u u e epo s a e no ed. 18
Thank you in ad ance o you commen s, his epo elies on he ac i e pa icipa ion o a wide ange 19
o s akeholde s, and we app ecia e you aking he ime o engage wi h us. 20
You s since ely, 21
D Tsungai Zengeya (on behal o he hi d s a us epo d a ing eam) 22
Ki s enbosch, 20 June 2023 23
1The p e ious s a us epo s a e a ailable o download a h p://ias epo .sanbi.o g.za/ , links o on-line
esou ces a e a ailable a end o his epo .
ii
Ci ing his publica ion 24
Fo ci a ions in he scien i ic li e a u e: Zengeya, T.A. & Wilson, J.R. (Eds.), 2023. The s a us o 25
biological in asions and hei managemen in Sou h A ica in 2022 [SECOND DRAFT FOR PUBLIC 26
COMMENT]. Sou h A ican Na ional Biodi e si y Ins i u e, Ki s enbosch and DSI-NRF Cen e o 27
Excellence o In asion Biology, S ellenbosch. h p://dx.doi.o g/10.5281/zenodo.8037187
28
Fo ci a ions in policy documen s: SANBI and CIB 2023. The s a us o biological in asions and hei 29
managemen in Sou h A ica in 2022 [SECOND DRAFT FOR PUBLIC COMMENT]. Sou h A ican Na ional 30
Biodi e si y Ins i u e, Ki s enbosch and DSI-NRF Cen e o Excellence o In asion Biology, 31
S ellenbosch. h p://dx.doi.o g/10.5281/zenodo.8037187
32
ISBN: o be included in he inal epo 33
Au ho s 34
Lead edi o s: Tsungai A. Zengeya, John R. Wilson 35
Chap e lead au ho s: Ka elyn T. Faulkne , Lau a M. Fe nández Winze , Michelle G e e, Sab ina 36
Kumschick, Siyasanga Miza, Emily J. McCulloch-Jones, Pe e C. le Roux, Ma hán Thea , B ian W. an 37
Wilgen, John R. Wilson & Tsungai A. Zengeya 38
Wi h con ibu ions om: Julie A. Coe zee, Nicholas Cole, Whi ney Engelb ech , Ma in P. Hill, Ca ol 39
Jacobs, Phe ole Manyama, Themba Mnguni, Zacha iah Mokganye, Debbie Mui , Wilma Nel, T udy 40
Paap, Iain Pa e son, Leoni P e o ius, Roge P ice, Tama a B. Robinson, A iwe Si uba, Louise S a o d, 41
And ew A. Tu ne , Anne T easu e, Ka abo Wanjau, And ew Wannenbu gh, Mike J. Wing ield, An on 42
Wol aa d & Cos as Zacha iades 43
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Table o Con en s 44
No e o eade ......................................................................................................................................... i 45
Ci ing his publica ion ......................................................................................................................... ii 46
Au ho s ................................................................................................................................................ ii 47
Table o Con en s .................................................................................................................................. iii 48
Fo ewo d by he Minis e o En i onmen , Fo es y and Fishe ies ..................................................... 49
P e ace by SANBI Boa d Chai ................................................................................................................ 50
P e ace by SANBI CEO ............................................................................................................................ 51
Lis o ac onyms...................................................................................................................................... 52
Glossa y ................................................................................................................................................. i 53
Summa y ................................................................................................................................................ xi 54
T ends in indica o s .......................................................................................................................... xiii 55
Chap e 1: In oduc ion .......................................................................................................................... 1 56
1.1 The impo ance o biological in asions o Sou h A ica ............................................................... 1 57
1.2 The manda e, pu pose, and s uc u e o he hi d s a us epo ................................................. 1 58
1.3 P ocess o he compila ion o he epo .................................................................................... 3 59
1.4 Indica o s ...................................................................................................................................... 7 60
1.5 Wo k lows and p o ocols .............................................................................................................. 8 61
1.6 Aspec s o biological in asions ha a e no co e ed ................................................................... 8 62
Box 1.1 The In e go e nmen al Science-Policy Pla o m on Biodi e si y and Ecosys em Se ices 63
(IPBES) hema ic assessmen o in asi e alien species and hei con ol (IAS Assessmen ) .............. 9 64
Box 1.2 The Kunming-Mon eal Global Biodi e si y F amewo k (GBF) o he Con en ion on 65
Biological Di e si y (CBD) .................................................................................................................... 9 66
Chap e 2: Pa hways ............................................................................................................................ 11 67
Key indings o pa hways ................................................................................................................. 11 68
Key gap o pa hways ........................................................................................................................ 11 69
Indica o s co e ed in he pa hway chap e ...................................................................................... 12 70
2.1 In oduc ion pa hway p ominence ............................................................................................. 12 71
2.2 In oduc ion a es ....................................................................................................................... 13 72
2.3 Wi hin-coun y pa hway p ominence ......................................................................................... 17 73
2.4 Wi hin-coun y dispe sal a es ................................................................................................... 17 74
Box 2.1. Wo k owa ds imp o ing he pa hways indica o s ............................................................. 20 75
2.5 T ends in pa hway indica o s ...................................................................................................... 22 76
Chap e 3: Species ................................................................................................................................ 24 77
Key indings o species ..................................................................................................................... 24 78
Key gaps o species and si es ........................................................................................................... 24 79
Indica o s co e ed in he species chap e ........................................................................................ 25 80
3.1 Numbe and s a us o alien species ............................................................................................ 25 81
3.2 Ex en o alien species ................................................................................................................ 26 82
3.3 Abundance o alien species......................................................................................................... 27 83
3.4 Impac o aliens ........................................................................................................................... 27 84
Box 3.1 Na i e-alien popula ions ...................................................................................................... 29 85
3.5 T end in species indica o s.......................................................................................................... 31 86
Chap e 4: Si es..................................................................................................................................... 33 87
Key indings o si es ......................................................................................................................... 33 88
Indica o s co e ed in he si es chap e ............................................................................................. 33 89
4.1 Alien species ichness ................................................................................................................. 33 90
4.2 Rela i e in asi e abundance ....................................................................................................... 36 91
4.3 Impac o in asions ..................................................................................................................... 38 92
Box 4.1 Es ima ing he cos s o in asions o Sou h A ica ................................................................ 38 93
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4.4 T ends in si es indica o s ............................................................................................................ 40 94
Chap e 5: In e en ions ...................................................................................................................... 41 95
Key indings ega ding in e en ions ................................................................................................ 41 96
Key gaps ega ding in e en ions ..................................................................................................... 42 97
Indica o s co e ed in he in e en ions chap e .............................................................................. 43 98
5.1 Inpu —quali y o he egula ion amewo k .............................................................................. 43 99
5.2 Inpu —money spen ................................................................................................................... 47 100
5.3 Inpu —planning co e age ........................................................................................................... 52 101
5.4 Ou pu —pa hways ea ed ......................................................................................................... 57 102
5.5 Ou pu —species ea ed ............................................................................................................. 58 103
5.6 Ou pu —si es ea ed ................................................................................................................. 61 104
5.7 Ou come—e ec i eness o pa hway ea men s ...................................................................... 62 105
5.8 Ou come—e ec i eness o species ea men s ......................................................................... 63 106
5.9 Ou come—e ec i eness o si e ea men s ............................................................................... 64 107
Box 5.1 The egula ion o in asi e species used in comme cial imbe plan a ions ........................ 66 108
Box 5.2 The G ea e Cape Town Wa e Fund ................................................................................... 68 109
Box 5.3 Success ul biological con ol o wa e hyacin h on a eu ophic sub- opical wa e -body .. 70 110
5.10 T ends in in e en ions indica o s ............................................................................................ 71 111
Chap e 6: The s a us o biological in asions and hei managemen in he P ince Edwa d Islands 75 112
Key indings o he PEIs.................................................................................................................... 75 113
Key gaps o he PEIs ......................................................................................................................... 76 114
Indica o s co e ed in he PEIs chap e ............................................................................................. 76 115
6.1 Pa hways ..................................................................................................................................... 76 116
6.2 Species ........................................................................................................................................ 81 117
6.3 Si es ............................................................................................................................................. 85 118
6.4 In e en ions ............................................................................................................................... 88 119
6.5 T ends in indica o s o he PEIs ................................................................................................. 95 120
Chap e 7: Gaps .................................................................................................................................. 100 121
Key gaps .......................................................................................................................................... 100 122
7.1 P ocess o iden i ying gaps ...................................................................................................... 100 123
7.2 Indica o s—imp o ing how in asions a e measu ed and p o iding a link o o he epo s .... 101 124
7.3 Pa hways— acking in asions ac oss Sou h A ica ................................................................... 101 125
7.4 Species & Si es—mapping in asions in space and o e ime ................................................... 101 126
7.5 Species & Si es—de e mining he impac s and cos s ............................................................... 102 127
7.6 In e en ions— he need o an o e -a ching policy and s a egy ........................................... 102 128
7.7 In e en ions—measu ing he e ec i eness o in e en ions ................................................. 103 129
7.8 Sugges ions o ex ensions o he scope o he epo ............................................................. 103 130
Acknowledgemen s ............................................................................................................................ 105 131
Re e ences .......................................................................................................................................... 105 132
Links o supplemen a y ma e ial and appendices ............................................................................ 112 133
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135

Fo ewo d by he Minis e o En i onmen , Fo es y and Fishe ies 136
P e ace by SANBI Boa d Chai 137
P e ace by SANBI CEO 138
These elemen s will be added p io o he inal epo . 139
Lis o ac onyms1
140
ASRARP Alien Species Risk Analysis Re iew Panel 141
A&IS Alien and In asi e Species as e e ed o ei he in he NEM:BA A&IS Regula ions o he 142
NEM:BA A&IS Lis s published unde he egula ions 143
CBD he Con en ion on Biological Di e si y o he Uni ed Na ions 144
CIB he Depa men o Science and Inno a ion-Na ional Resea ch Founda ion Cen e o 145
Excellence o In asion Biology 146
DALRRD Depa men o Ag icul u e, Land Re o m and Ru al De elopmen 147
DFFE Depa men o Fo es y, Fishe ies, and he En i onmen 148
EICAT En i onmen al Impac Classi ica ion o Alien Taxa 149
GBF he Kunming-Mon eal Global Biodi e si y F amewo k o he CBD 150
hmgc hal -minu e g id cell (used o mapping on he P ince Edwa d Islands) 151
NEM:BA he Na ional En i onmen al Managemen : Biodi e si y Ac (Ac No. 10 o 2004) 152
NEM:BA A&IS: see A&IS 153
NRM Na u al Resou ce Managemen (a di ision o he DFFE) 154
PEIs he P ince Edwa d Islands 155
qdgc qua e -deg ee g id cell 156
RAC he Re e ence and Ad iso y Commi ee (o his hi d s a us epo ) 157
SANBI he Sou h A ican Na ional Biodi e si y Ins i u e 158
SAPIA he sou he n A ican Plan In ade s A las 159
SEICAT Socio-Economic Impac Classi ica ion o Alien Taxa 160
W W Wo king o Wa e 161
ZAR Sou h A ican Rands 162
163
164
1 These ac onyms a e used ei he in his epo o in he supplemen a y ma e ial. Fo edi o ial con en ions see
supplemen a y ma e ial S1.1.
i
Glossa y1 165
Abundance (c . dis ibu ion, ex en ): a measu e o he numbe o indi iduals, co e age, o biomass o 166
an o ganism in a speci ied si e. 167
Adap i e managemen : a s uc u ed, i e a i e p ocess ha includes he se ing o goals, egula 168
moni o ing o p og ess owa ds he achie emen o hose goals, and, based on he indings o he 169
moni o ing, he adap a ion o managemen o imp o e i s e ec i eness o a e ision o he goals. 170
Adap i e managemen is use ul whe e he ou pu s and ou comes o managemen a e unce ain, and 171
whe e an app oach o lea ning-by-doing can educe unce ain y o e ime. 172
Alien species (c . ex alimi al, na i e species): a species ha is p esen in a si e ou side i s na u al 173
ange as a esul o human ac ion ha has enabled i o o e come biogeog aphic ba ie s. 174
Assessmen : a c i ical e alua ion o in o ma ion. 175
Bene i : cos a io: see e u ns on in es men 176
Biodi e si y: he a iabili y among li ing o ganisms om all sou ces including e es ial, ma ine, and 177
o he aqua ic ecosys ems and he ecological complexes o which hey a e pa ; his includes di e si y 178
wi hin species, be ween species and o ecosys ems. 179
Biological in asions: he phenomenon o , and sui e o p ocesses ha a e in ol ed in de e mining, he 180
anspo o o ganisms o si es ou side hei na i e ange by human ac i i ies and he a e o he 181
o ganisms in hei new anges. 182
Biological con ol (syn. biocon ol): he use o specimens o one species o he pu pose o p eying 183
on, pa asi izing on, damaging, killing, supp essing o con olling a specimen o ano he species. 184
Biocon ol: see Biological con ol. 185
Biome: a la ge na u ally occu ing communi y o plan s and animals ha ha e common cha ac e is ics 186
in simila physical en i onmen s, e.g., dese o o es . 187
Biosecu i y: measu es ha a e aken o s op he in oduc ion o dispe sal o o ganisms ha m ul o 188
human, animal, o plan li e. 189
Con es ed species: alien species o which he e is dispu e abou he app op ia e (i any) egula o y 190
lis ing. Also e e ed o as con lic -gene a ing species. Such species ha e in some cases been lis ed as 191
ca ego y 2 unde he NEM:BA A&IS Regula ions, whe eby a pe mi can be issued o s akeholde s o 192
conduc o he wise illegal ac i i ies wi h he lis ed alien species. The con es a ion may he eby be 193
esol ed. 194
Compliance: The ac ion o ac o complying wi h ins uc ions, in his second epo such ins uc ions 195
p ima ily e e o he p o isions o NEM:BA. 196
Compliance no ice (also p e-compliance no ice): an o icial documen se ed by an en i onmen al 197
managemen inspec o on a pe son when he e a e easonable g ounds o belie ing ha ha pe son 198
has no complied wi h a p o ision o he law o wi h a e m o condi ion o a pe mi , au ho isa ion o 199
o he ins umen issued in e ms o such law. A p e-compliance no ice is a w i en no ice o in en ion 200
1These de ini ions a e based on hose in he second epo , Richa dson e al. (2010), Wilson e al. (2017), and
an Wilgen e al (2020a) wi h conside a ion o de ini ions gi en in ele an Sou h A ican and in e na ional
legisla ion, speci ically he NEM:BA and i s A&IS Regula ions, and he CBD (
h ps://www.cbd.in /in asi e/ e ms.sh ml). These co e e ms used in his hi d epo and in he
supplemen a y ma e ial o he hi d epo . Fo edi o ial con en ions see supplemen a y ma e ial S1.1.
ii
o issue a compliance no ice, which p ecedes he issuing o a compliance no ice and in i es he pe son 201
o whom i has been issued o make ep esen a ions o he en i onmen al managemen inspec o . 202
Con ainmen : he goal o p e en ing o educing he sp ead o in asi e species. 203
Con aminan : he acciden al in oduc ion o an alien species wi h an in en ionally anspo ed 204
commodi y wi h which he o ganism has a speci ic, na u al associa ion. 205
Con ol: any ac ion aken o p e en he ecu ence, e-es ablishmen , e-g ow h, mul iplica ion, 206
p opaga ion, egene a ion o sp eading o an alien species. 207
Con ic ion: a e dic o guil y issued by a compe en cou ollowing he p osecu ion o a pe son 208
suspec ed o ha ing commi ed a c iminal o ence. 209
Co ido : he na u al sp ead o an alien species in o a new egion h ough a human-cons uc ed 210
anspo in as uc u e ha connec s p e iously unconnec ed egions, and in he absence o which 211
dispe sal would no ha e been possible. 212
Di ec i e (also p e-di ec i e): an o icial documen se ed by an en i onmen al managemen 213
inspec o on a pe son when such pe son is: a) a pe mi holde and is suspec ed o no complying wi h 214
he condi ions unde which a pe mi has been issued o no aking all he equi ed s eps o p e en o 215
minimise ha m o biodi e si y by he alien species o which he pe mi ela es; o b) a landowne and 216
is suspec ed o no ul illing hei du y o ca e in ela ion o lis ed alien species on hei land. A di ec i e 217
di ec s a pe son o ake s eps o emedy ha m caused o biodi e si y caused by such pe son’s non-218
compliance o ailu e o ul il he landowne ’s du y o ca e. A p e-di ec i e is a w i en no ice o 219
in en ion o issue a di ec i e, which p ecedes he issuing o a di ec i e and in i es he pe son o whom 220
i is issued o make ep esen a ions o he en i onmen al managemen inspec o . 221
Dispe sal (syn. sp ead): mo emen o o ganisms wi hin a de ined si e ha is acili a ed ei he 222
in en ionally o acciden ally by humans, o ha occu s na u ally. 223
Dis ibu ion: he ex en and abundance o a species o e a gi en si e. 224
E adica ion: he comple e emo al o all indi iduals and p opagules o a popula ion o an alien species 225
om a pa icula si e o which he e is a negligible likelihood o ein asion. 226
Escape (c . elease): he sp ead o an alien species ha was in en ionally in oduced and kep in 227
cap i i y o cul i a ion o si es ou side o cap i i y o cul i a ion. Includes bo h na u al sp ead and he 228
acciden al o in en ional illegal human-media ed dispe sal o li e o ganisms om he si e o cap i i y 229
o cul i a ion. 230
Es ablished: see na u alised. 231
Ex en (c . abundance, dis ibu ion): he b oad-scale a ea o e which an o ganism occu s. The spa ial 232
scale o e which ex en is measu ed needs o be speci ied. The occupancy o si es a a ine-spa ial 233
scale is o en equi alen o he abundance. 234
Ex i pa ion (c . e adica ion): he esul o a con ol ope a ion whe eby all indi iduals in a popula ion 235
a e emo ed. O he popula ions migh be close by o pa hways o in oduc ion and dispe sal a e s ill 236
ope a ing such ha he p obabili y o e-in asion is p obable o no known.
237
Ex alimi al (c . alien species, na i e species): a na i e species ha has been in oduced by humans 238
o a pa o Sou h A ica ha is ou side o he species’ na i e dis ibu ion ange. I does no include 239
na i e species ha ha e ex ended hei dis ibu ion by na u al dispe sal. 240
Impac : he e ec o an alien species on he physical, chemical, and biological en i onmen . I can 241
include bo h nega i e and posi i e e ec s. 242
iii
Incu sion: an isola ed popula ion o a pes , weed, o alien species, ha usually has a limi ed spa ial 243
ex en and has been ecen ly de ec ed a a si e. In gene al, he managemen o incu sions is e e ed 244
o as incu sion esponse. 245
Indica o : a se o measu emen s ha gi e speci ic in o ma ion abou he s a e o some hing. 246
Indigenous species: see Na i e species. 247
In e en ions: he ull a ie y o ac ions aken in esponse o biological in asions, including di ec 248
ac ions, i.e., con ol, and indi ec ac ions like moni o ing, egula ion, and esea ch. 249
In oduced: see In oduc ion. 250
In oduc ion: he mo emen o an alien species (ei he acciden ally, in en ionally and legally, o 251
in en ionally and illegally) by human ac i i y, o a egion ou side i s na i e ange. In oduc ions can 252
also e e o species which we e in oduced o one coun y by humans and sp ead na u ally o 253
neighbou ing coun ies. In he con ex o in oduc ions, he e m ‘acciden al’ is p e e ed o he 254
synonymous e m ‘unin en ional’. 255
In asion: see Biological in asions. 256
In asion deb : he po en ial inc ease in biological in asions a a si e o e a pa icula ime ame in 257
he absence o any in e en ions (Rouge e al., 2016). I is composed o he numbe o new species 258
ha will be in oduced (in oduc ion deb ), he numbe o species ha will become in asi e (species-259
based in asion deb ); he inc ease in a ea a ec ed by in asions (a ea-based in asion deb ); and he 260
inc ease in he nega i e impac s caused by in oduced species (impac -based in asion deb ). 261
In asi e alien species: see In asi e species. 262
In asi e species: Alien species ha sus ain sel - eplacing popula ions o e se e al li e cycles, p oduce 263
ep oduc i e o sp ing, o en in e y la ge numbe s a conside able dis ances om he pa en and/o 264
si e o in oduc ion, and ha e he po en ial o sp ead o e long dis ances. 265
In asi eness: he ea u es o an alien o ganism, such as hei li e-his o y ai s and modes o 266
ep oduc ion, ha de ine hei capaci y o become an in asi e species. 267
Lis ed alien species: species which a e lis ed unde he NEM:BA A&IS Regula ions ei he as ‘lis ed 268
in asi e species’ (which a e in ended o only include alien species ha a e p esen in Sou h A ica) o 269
‘p ohibi ed alien species’ (which a e in ended o only be species ha a e absen om Sou h A ica). 270
Moni o ing: a sys ema ic p ocess o collec ing and analysing in o ma ion o ack p og ess owa ds 271
eaching s a ed goals, ha acili a es he assessmen o he e icacy o in e en ions. 272
Na i e-alien popula ions: a popula ion o a axon ha is na i e o a pa o Sou h A ica, bu ha was 273
ounded by indi iduals mo ed by di ec human agency, o e a biogeog aphical ba ie , o an a ea 274
beyond he species’ na i e ange (i.e., i can be conside ed a biological in asions) (see Box 3.1). 275
Na i e species (syn. indigenous species, c . alien species, ex alimi al): species ha a e ound wi hin 276
hei na u al ange whe e hey ha e e ol ed wi hou human in e en ion (in en ional o acciden al). 277
Also includes species ha ha e expanded hei ange as a esul o human modi ica ion o he 278
en i onmen ha does no di ec ly impac dispe sal (e.g., popula ions a e s ill conside ed na i e i 279
hey esul om an inc ease in ange as a esul o wa e ed ga dens, bu a e conside ed alien i hey 280
esul om an inc ease in ange as a esul o sp ead along human-c ea ed co ido s linking p e iously 281
sepa a e biogeog aphic egions). 282
Na u alised (syn. es ablished): Alien species ha sus ain sel - eplacing popula ions o se e al li e 283
cycles o o e a gi en pe iod o ime wi hou di ec in e en ion by people, o despi e human 284
in e en ion. 285
1
Chap e 1: In oduc ion 410
Au ho s: John R. Wilson, Tsungai A. Zengeya 411
1.1 The impo ance o biological in asions o Sou h A ica 412
Biological in asions a e amongs he leading causes o global change— hey ha e had p o ound 413
nega i e impac s on people and na u e o cen u ies; a e cu en ly a signi ican d ain on Sou h A ica’s 414
sus ainable de elopmen and a e nega i ely impac ing na i e biodi e si y; and pose a majo h ea o 415
bo h he quali y o li e o u u e gene a ions and he globally unique lo a and auna ha a e an 416
in eg al pa o his coun y (Pyšek e al. 2020, an Wilgen e al. 2020). The p oblem is complica ed 417
and se o g ow (Chap e s 2 and 6). In asi e species come om many di e en axa, in ade di e en 418
habi a s, and cause a ious ypes o impac s some imes in ways which a e no ye ully unde s ood 419
bu ha will ha e p o ound e ec s on he abili y o ecosys ems o deli e se ices o people (Chap e s 420
3, 4, and 6; an Wilgen e al. 2020). 421
Thank ully, howe e , signi ican p og ess has been made in educing impac s and p e en ing new 422
in asions (Chap e 5). Ta ge ed in e en ions can be highly cos -e ec i e, and so, while in e en ions 423
can be complica ed and cos ly, by wo king oge he as a socie y we can p o ec ou biodi e si y and 424
na u al capi al om biological in asions. The na u e o he impac s and he ypes o esponses needed 425
means ha biological in asions a e a signi ican c oss-cu ing issue o Sou h A ica ha is managed 426
by a ange o s akeholde s using a a ie y o app oaches. 427
1.2 The manda e, pu pose, and s uc u e o he hi d s a us epo 428
The issue o biological in asions has ecei ed signi ican ecen global a en ion in pa icula wi h he 429
p oduc ion and upcoming elease in Oc obe 2023 o he In e go e nmen al Science-Policy Pla o m 430
on Biodi e si y and Ecosys em Se ices (IPBES)’s “Thema ic assessmen o in asi e alien species and 431
hei con ol” (Box 1.1); and he Kunming-Mon eal Global Biodi e si y F amewo k (GBF) ha was 432
ag eed unde he Con en ion on Biological Di e si y (CBD) in Decembe 2022 (Box 1.2). This hi d 433
s a us epo si s i mly wi hin his con ex , bu he speci ic manda e o he s a us epo o iginally 434
a ose om sec ion 11 o he Na ional En i onmen al Managemen : Biodi e si y Ac , Alien and In asi e 435
Species Regula ions (NEM:BA A&IS Regula ions) ha we e published 1 Augus 2014 and p omulga ed 436
in Oc obe 2014. Re ised egula ions we e published 18 Sep embe 2020 and p omulga ed 1 Ma ch 437
2021, wi h sec ion 13 s a ing: 438
(1) The Ins i u e1 o a body designa ed by he Ins i u e mus , o he pu pose o epo ing as 439
con empla ed in sec ion 11(1)(a)(iii) o he Ac , submi a epo on he s a us o lis ed 440
1 The Sou h A ican Na ional Biodi e si y Ins i u e (SANBI)

2
in asi e species o he Minis e wi hin h ee yea s o he da e on which hese egula ions 441
come in o e ec , and a leas e e y h ee yea s he ea e 1. 442
(2) A epo con empla ed in sub- egula ion (1) mus con ain a summa y and assessmen o — 443
(a) he s a us o lis ed in asi e species and o he species ha ha e been subjec ed o a isk 444
assessmen ; and 445
(b) he e ec i eness o hese egula ions and con ol measu es based in e alia on
446
in o ma ion om— 447
(i) no i ica ions ecei ed om owne s o land ega ding lis ed in asi e species 448
occu ing on hei land; 449
(ii) pe mi s issued o lis ed in asi e species; 450
(iii) In asi e Species Moni o ing, Con ol and E adica ion Plans ecei ed om o gans 451
o s a e and managemen au ho i ies o p o ec ed a eas; and 452
(i ) eme gency in e en ions and en o cemen ac ions in ol ing lis ed in asi e 453
species. 454
(3) In p epa ing a epo con empla ed in sub- egula ion (1), he Ins i u e mus ca y ou he 455
esea ch and moni o ing necessa y o iden i y he ma e s con empla ed in sub- egula ion 456
(2). 457
458
Mo e b oadly, howe e , he s a us epo aims o s eng hen he links be ween basic esea ch, policy, 459
and managemen , by p o iding suppo o decision make s ha is policy ele an bu no policy 460
p esc ip i e (Figu e S.1). 461
The i s epo was p oduced in 2017 and eleased in 2018, and he second p oduced in 2020 and 462
eleased in 2021. Bo h we e s uc u ed a ound an indica o amewo k ha explici ly conside s 463
biological in asions in e ms o pa hways, species, si es, and in e en ions (wi h indica o s on 464
in e en ions di ided in o hose conside ing inpu s, ou pu s, and ou comes, Figu e 1.1). This indica o 465
amewo k p o ides a anspa en and objec i e me hod o he es ablishmen o a baseline agains 466
which o assess ends, se ealis ic managemen a ge s, and o highligh ing impo an gaps in he 467
e idence needed o suppo decision-making. This hi d epo ou lines ends o e he pas h ee 468
yea s o he ou headline indica o s and o he 20 indica o s acking pa hways, species, si es, and 469
in e en ions. I akes ime o compile, e ise, and p oduce hese epo s. The e o e a cu -o da e is 470
needed, a e which no new da a a e conside ed. This hi d epo is hus en i led ‘The s a us o 471
biological in asions and hei managemen in Sou h A ica in 2022’, as i epo s on he s a us up o 472
he end o 2022, al hough i is due o be inalised by Oc obe 2023 and eleased ea ly in 2024. 473
The epo is comp ised o chap e s based on he amewo k (i.e., on pa hways, species, si es, and 474
in e en ions). Each chap e s a s wi h a summa y o he s a e o he indica o s, and hen a discussion 475
o key changes o he indica o s and ecen no ewo hy e en s, wi h impo an case-s udies in he 476
o m o ex boxes. In addi ion, o his epo , a chap e -leng h case s udy is p o ided on “The S a us 477
o Biological In asions and hei Managemen in he P ince Edwa d Islands”. The P ince Edwa d Islands 478
1 So echnically his epo is due Ma ch 2024, al hough in keeping wi h a h ee yea cycle, he epo was
p oduced by Oc obe 2023.
3
(Ma ion Island and P ince Edwa d Island) lie in he Sou he n Ocean, 1400 km om con inen al Sou h 479
A ica, and a e dis inc om he mainland bo h in e ms o he na u e o biological in asions and how 480
hey a e managed. A inal chap e e alua es he deg ee o which gaps iden i ied in he p e ious 481
epo s ha e been illed, looks a addi ional key gaps ha need o be add essed in u u e epo s, and 482
iden i ies ecommenda ions ele an o how Sou h A ica unde s ands and manages biological 483
in asions. Much o he de ail unde lying he p oduc ion o he epo is con ained wi hin he 484
appendices and supplemen a y ma e ial a ailable on-line (links o hem a e on he las page o he 485
epo ). 486
A ocus o his epo is o p oduce wo k- lows (see Sec ion 1.5) and ensu e da a a e FAIR1 and idy 487
(see Sec ion S1.4) in line wi h in e na ional bes p ac ice (IPBES 2018). In so doing, he epo p ocess 488
should be mo e sus ainable in ha he p ocesses used a e documen ed and can be epea ed. The 489
longe - e m plan is o de elop an on-line esou ce wi h indica o alues upda ed as soon as new 490
in o ma ion becomes a ailable (i.e., a dashboa d) ha can be used o p oduce epo s on demand, 491
and o m he basis bo h o semi-au oma ed annual epo s and less equen comp ehensi e epo s 492
(see Sec ion S.1.2, no ing ha such plans will need o be compa ible wi h egula o y equi emen s—493
cu en ly iennial epo s a e manda ed). The in en ion o his epo is hus o p o ide an upda e o 494
he second epo , and ocus on he p ocess, ecognising ha all iden i ied da a sou ces ha e no ye 495
been inco po a ed (see Appendix 1 o da a sou ces used, and hose ha will be inco po a ed in 496
u u e). 497
1.3 P ocess o he compila ion o he epo 2 498
The p ocess was b oadly simila o he i s wo epo s (Figu e 1.1), wi h la gely he same eam, 499
consis ing o he Sou h A ican Na ional Biodi e si y Ins i u e as he lead ins i u e, he Cen e o 500
In asion Biology as a collabo a ing pa ne , and a ious manage s, esea che s, p i a e indi iduals, 501
and ins i u ions p o iding in o ma ion and commen s on d a epo s. 502
Re iew o elease o he 2nd epo and essen ial wo k- lows iden i ied: The SANBI-CIB d a ing eam 503
e lec ed on he epo launch and how he epo was ecei ed, and in pa icula iden i ied he need 504
o close engagemen wi h a ec ed go e nmen depa men s. In pa icula , i was no ed ha by 505
p o iding an oppo uni y o e alua e he indings and de elop app op ia e esponses ahead o he 506
epo launch, a ec ed agencies would be in a be e posi ion o espond o and up ake he indings. 507
1 Findable, Accessible, In e ope able, and Reusable: www.go- ai .o g/
2 The p ocess includes u u e planned e en s w i en as i hey ha e al eady occu ed. These will be upda ed as
he epo de elops bu a e included he e o comple eness and in he ense hey will be in he inal epo .
4
The d a ing eam also iden i ied essen ial wo k- lows o he p oduc ion o he epo ha needed o 508
be se up du ing his epo cycle (Sec ion 1.5). 509
Appoin a e e ence and ad iso y commi ee (RAC): a RAC was es ablished o p o ide o e sigh o he 510
p ocess and e iew documen s p oduced. The i s mee ing o he RAC was on 22 Feb ua y 2022 a 511
which a p oposed able o con en s was app o ed. A d a o he epo was sen o he RAC on 9 512
Sep embe 2022, and discussed a he second mee ing o he RAC on 28 Sep embe 2022. The epo 513
was e ised and se ou o public commen on 20 Decembe 2022. The second d a o public 514
commen was sen o he RAC a he same ime as i was made public, and a mee ing held 26 June 515
2023. The Chai o he RAC also e iewed how he commen s ecei ed du ing all ounds o e iew 516
we e add essed, i.e., ac ed in a e iew edi o ole. Finally, he RAC p o ided ad ice bo h in e ms o 517
he public elease o he epo , and on e lec ing on he p ocess. 518
Colla e and e iew a ailable in o ma ion: In o ma ion was inco po a ed in o he epo p ima ily om 519
published li e a u e and unpublished in o ma ion p o ided by s akeholde s. In o ma ion con ained in 520
he epo is based on da a a ailable o he epo w i ing eam as o he end o Decembe 2022 (see 521
Supplemen a y Ma e ial o each chap e and Appendix 1). 522
S akeholde engagemen : Du ing epo p oduc ion, s akeholde engagemen was an on-going 523
p ocess linked o he o he ac i i ies. Ini ially he d a ing eam engaged di ec ly wi h specialis 524
con ibu o s o ob ain in o ma ion ha was no eadily accessible and iden i ied s akeholde s o be 525
con ac ed o inpu and e iew. Con ibu o s we e iden i ied ini ially based on hose iden i ied 526
p e iously, and hose who p o ided commen s we e asked o upda es. New po en ial con ibu o s 527
we e con ac ed on an ad hoc basis as in o ma ion became a ailable and in esponse o he public 528
consul a ion. Con ibu o s came om academic ins i u ions; esea ch ins i u es and science councils; 529
na ional, p o incial, and local go e nmen depa men s; and om p i a e indi iduals whom we e 530
in e es ed and a ec ed. Con ibu ions om he iden i ied s akeholde s we e in he o m o da a 531
p o ision and commen ing on d a s. 532
The epo p ocess is on-going. The e a e in o ma ion sou ces a ailable ha , gi en cons ain s, could 533
no be ully inco po a ed in his hi d epo (in pa icula see Table S3.1 o in o ma ion sou ces ha 534
need o be inco po a ed in o he species lis ). In cases whe e in o ma ion was belie ed o be a ailable 535
bu was no o hcoming, he lack o in o ma ion is lagged ei he in he epo o in he supplemen a y 536
ma e ial. Finally, some in o ma ion is simply no a ailable as i has ei he no been ga he ed o 537
app op ia ely cu a ed. Fo a discussion on gaps see Chap e 7. 538
5
539
Figu e 1.1 Key s eps in he p oduc ion o he epo ‘ he S a us o Biological In asions and hei 540
Managemen in Sou h A ica in 2022’. The Minis e is he Sou h A ican Minis e o Fo es y, Fishe ies 541
and he En i onmen ; he RAC is he esea ch and ad iso y commi ee; and SANBI is he Sou h A ican 542
Na ional Biodi e si y Ins i u e. 543
S a us epo eam e iew he elease o he 2
nd
epo
and iden i y wo k lows needed o he 3
d
epo
(Jun–Dec 2021)
Colla e and
e iew
a ailable
in o ma ion
Iden i y and
engage
specialis
con ibu o s
Re e ence and ad iso y commi ee
Assign alues o indica o s
Re ised d a o public commen
(Dec 2022–Feb 2023
S akeholde engagemen
Iden i y
s akeholde s
S akeholde
e iew
(Dec 2022–Feb
2023)
Re ise d a a e public commen s
(Feb–Jun 2023)
Final e isions and epo p oduc ion
(Jul–Aug 2023)
Media
enqui ies
Submi o SANBI Boa d (Sep 2023)
Submi o Minis e (Oc 2023)
Public elease (Jan 2024)
Re lec on he p ocess
D a able o con en s (Feb 2022)
Mee ing
(22 Feb 2022)
Appoin
a RAC
(Jan 2022)
Con e ence and
wo kshop
p esen a ions
Re iew d a
Re iew o
e ised d a ,
and esponse
o commen s
ecei ed
Mee ing
(Dec o Jan
2023)
2
nd
ound o
s akeholde
e iew &
addi ional
expe e iew
(Jun–Jul 2023)
Check
esponses o
commen s
ecei ed
2
nd
s a us epo inalised
(2 No 2020)
2
nd
s a us epo launched
(28 May 2021)
Engage wi h
go e nmen on
hei esponse
o key indings
(Oc –Dec 2023)
P oduce d a epo
(Sep 2022)
Mee ing
(28 Sep 2022)
Mee ing
(26 Jun 2023)
Re ised d a o public commen
(Jun–Jul 2023)
6
Re iew o d a epo s: A d a was comple ed in Sep embe 2022 and sen o he RAC o in e nal 544
e iew. This was hen discussed a a mee ing o he RAC on 28 Sep embe , e ised, and sen ou o 545
public e iew by expe s and s akeholde s o a pe iod o 10 weeks (20 Decembe 2022–28 Feb ua y 546
2022). The eques o e iew was submi ed o a Sou h A ican lis se e on biological in asions 547
([email p o ec ed]), heads o ele an na ional and p o incial go e nmen depa men s, 548
heads o ele an academic depa men s and ins i u ions, and p o essional socie ies and o ums 549
(including he Royal Socie y o Sou h A ica; he Akademie i We enskap en Kuns; he Zoological, 550
En omological, and Bo anical Socie ies; Bi dli e Sou h A ica; and he Wildli e and En i onmen Socie y 551
o Sou h A ica). A copy o he i s d a o public commen was a ached o he o mal no ice and 552
was a ailable o download online (h p://dx.doi.o g/10.5281/zenodo.7414804).
553
In June 2023, he nex d a o he epo was p oduced and sen o public commen o 6 weeks using 554
he same links as p e iously (20 June 2023–31 July 2023). In addi ion, he epo was sen o wo 555
independen expe s om Sou h A ica, one in e na ional expe , and membe s o he RAC. A copy o 556
he second d a o public commen was a ached o he o mal no ice and was a ailable o 557
download online (h p://dx.doi.o g/10.5281/zenodo.8037187).
558
Du ing he i s ound o ex e nal public e iew, commen s we e ecei ed om 19 sou ces, 559
ep esen ing 10 ins i u ions including he DFFE and he DWS. Du ing he second ound o ex e nal 560
public e iew, commen s we e ecei ed om XX sou ces, ep esen ing YY ins i u ions…1. 561
All eedback was eco ded and he commen s esponded o in line wi h in e na ional bes p ac ice 562
(IPBES 2018). The inpu s and esponses o he eques s o e iew, we e documen ed and a e a ailable 563
o sc u iny om SANBI on eques . 564
P oduce and elease he inal epo : Following he commen s om he inal ound o e iew ha 565
closed 31 July 2023, he epo was edi ed, and a comple e e sion sen in Augus 2023 o he SANBI 566
G aphics eam o edi ing, layou , design, and p in ing. A ully laid ou e sion o he epo was hen 567
submi ed o he SANBI Boa d in Sep embe 2023 o hei conside a ion. A e boa d app o al, he 568
SANBI CEO submi ed he epo o he Minis e o Fo es y, Fishe ies and he En i onmen . A he 569
same ime a copy o he epo was submi ed o he DFFE and he DALRRD as he key ecei e s o he 570
epo . This p o ided he depa men s wi h an oppo uni y o p epa e o esponding o media 571
enqui ies o public conce ns aised and o seek cla i ica ion om he epo d a ing eam as needed, 572
no ing ha no changes could be made o he epo du ing his pe iod. To maximise publici y and 573
media up ake o he epo , he epo is in ended o be eleased o he public in ea ly Janua y 2024 574
1 he numbe o people and ins i u ions commen ing o be added la e , po en ially combined i he e is a la ge
degee o o e lap.

7
in ime o he esh news cycle o he yea . As wi h p e ious epo s, in o ma ion will be included in 575
he Sou h A ican S a e o he En i onmen Repo p ocess (h p://soe .en i onmen .go .za/soe /).
576
Re lec on he p ocess: A e he public elease o he epo he s a us epo eam will con ene a 577
mee ing wi h key s akeholde s (including membe s o he RAC) o e lec on he p ocess used o 578
compile he epo and o iden i y a eas o imp o emen o subsequen epo s (see Chap e 7). 579
1.4 Indica o s 580
This epo is s uc u ed a ound he 20 indica o s and 4 high-le el indica o s ou lined in Wilson e al. 581
(2018) (Figu e 1.2) and adhe es b oadly o he published indica o ac shee s1. Howe e , he e ha e 582
been sligh upda es and co ec ions o how some hings we e sco ed, and so he indica o s should be 583
ead in conce wi h he me ada a o he species lis and o he wo k lows, wi h he mo e ecen 584
documen s aking p ecedence. Speci ically, he echnical de ails on sco ing he indica o s and he high-585
le el indica o s a e a ailable in he supplemen a y ma e ial. Fully e ised and upda ed indica o 586
ac shee s will be p o ided oge he wi h he nex epo . 587
588
Figu e 1.2 Indica o s used in he epo (based on Wilson e al. 2018). 589
No ably, he baselines p oposed in p e ious epo s needed o be e ised in some ins ances (e.g., due 590
o e o s in he o iginal alues). This means ha i is no always app op ia e o compa e alues 591
be ween he epo s, and in some cases he epo calcula ed he alues ha should ha e been in 592
p e ious epo s. Changes o e ime om hese e ised baselines a e p esen ed and discussed in his 593
1The indica o ac shee s can be downloaded a , h ps:// inyu l.com/5n6 bymh
5. Numbe and s a us o alien species
6. Ex en o alien species
7. Abundance o alien species
SPECIES
SITES
9. Alien species ichness
10. Rela i e in asi e abundance
PATHWAYS
1. In oduc ion pa hway p ominence
3. Wi hin-coun y pa hway p ominence
INTERVENTIONS
2. In oduc ion a es
4. Wi hin-coun y dispe sal a es
18.
E ec i eness o
pa hway ea men s
OUTCOMES
8. Impac o alien species
11. Impac o in asions
19. E ec i eness o
species ea men s
20. E ec i eness o si e
ea men s
OUTPUTS
16. Species ea ed
17. Si es ea ed
INPUTS
14. Planning co e age
HIGH LEVEL
A. Ra e o un egula ed in oduc ion
o new species
HIGH LEVEL
B. Numbe o in asi e species ha
ha e majo impac s
HIGH LEVEL
C. Ex en o a ea ha su e s majo
impac s om in asions
HIGH LEVEL
D. Le el o success in managing
in asions
15. Pa hways ea ed
13. Money spen
12. Quali y o egula o y
amewo k
8
epo , and di e ences in he calcula ion me hods used be ween he epo s a e no ed in he 594
supplemen a y ma e ial. 595
1.5 Wo k lows and p o ocols 596
Gi en he need o a epea able, anspa en p ocess, a ious wo k lows we e iden i ied and 597
cons uc ed o ou line how he epo was pu oge he and o in o m u u e epo p oduc ion. These 598
a e discussed in he ele an chap e s and p esen ed in ull in Appendix 4. They a e lis ed he e o 599
e e ence: 600
• In oduc ion pa hway p ominence; 601
• T acking da a sou ces; 602
• Adding alien axa and en ichmen da a o he species lis ; 603
• Upda ing he pe mi da abase; 604
• Money spen ; and 605
• Alien axa impac assessmen . 606
Mi o ing he abo e wo k lows, a wo k low was also es ablished o sou cing, cap u ing, and epo ing 607
in o ma ion o he P ince Edwa d Islands (Chap e 6). Fo u u e epo wo k lows a e planned o : 608
P ocessing occu ence eco ds o gi e species ichness and abundance es ima es a di e en spa ial 609
uni s; Impac s on key ecosys em se ices; Regula o y p ocesses (beyond jus he pe mi da abase); 610
E alua ing con ol plans and hei implemen a ion; and Compliance and inspec ions and cou cases 611
Some o hese wo k lows equi ed speci ic p o ocols whe e he in en ion is o hese o be applied 612
ou wi h he epo . Fo example, a p o ocol has been se up o classi y na i e-alien popula ions 613
(Nelu ule e al. 2022, Box 3.1). 614
1.6 Aspec s o biological in asions ha a e no co e ed 615
The aspec s no co e ed in his epo a e la gely he same as hose no co e ed in p e ious epo s 616
(see supplemen a y ma e ial S1.6). COVID-19 has had p o ound impac s on he li es o Sou h A icans. 617
Howe e , in he absence o an explici analysis as o how he pandemic and he esponse by he 618
go e nmen (e.g., he na ional lockdowns) di ec ly a ec ed biological in asions, he impac o COVID-619
19 is no explici ly conside ed he e, excep whe e he e we e palpable impac s on he indica o s (e.g., 620
he signi ican d op in ade and a el a ec ed he indica o s on in oduc ion pa hway p ominence 621
and wi hin-coun y pa hway p ominence, c . Figu e S2.19). 622
623
9
Box 1.1 The In e go e nmen al Science-Policy Pla o m on Biodi e si y and Ecosys em Se ices 624
(IPBES) hema ic assessmen o in asi e alien species and hei con ol (IAS Assessmen ) 625
The In e go e nmen al Science-Policy Pla o m on Biodi e si y and Ecosys em Se ices (IPBES) is an 626
independen in e go e nmen al body es ablished by S a es o s eng hen he science-policy in e ace 627
o biodi e si y and ecosys em se ices o he conse a ion and sus ainable use o biodi e si y, long-628
e m human well-being and sus ainable de elopmen . In 2018, a global IAS Assessmen was ini ia ed 629
and is o be p esen ed o app o al by he pa ies o IPBES as pa o he 10 h IPBES Plena y (28 Augus –630
2 Sep embe 2023). The aim o he IAS Assessmen is “ o c i ically e alua e a ailable e idence on he 631
se e i y o he h ea o biological in asions o unde pin po en ial op ions o decision-making.” The 632
epo is due o be eleased o he public la e in 2023 (~Oc obe 2023). As such i was no possible o 633
include he indings in his hi d epo , bu he epo will o m a co e sou ce o he de elopmen o 634
he nex comp ehensi e epo . Fo de ails see h ps://ipbes.ne /in asi e-alien-species-assessmen 635
636
Box 1.2 The Kunming-Mon eal Global Biodi e si y F amewo k (GBF) o he Con en ion on 637
Biological Di e si y (CBD) 638
One pu pose o his epo is o acili a e Sou h A ica’s epo ing o in e na ional bodies on biological 639
in asions, including o he CBD. As such he aim is o align his epo wi h in e -go e nmen al 640
epo ing p ocesses and indica o s. The CBD a a mee ing in Decembe 2022 ag eed o he Kunming-641
Mon eal Global Biodi e si y F amewo k (GBF). Ta ge 6 o he GBF ocusses on biological in asions: 642
Elimina e, minimize, educe and o mi iga e he impac s o in asi e alien species on biodi e si y and 643
ecosys em se ices by iden i ying and managing pa hways o he in oduc ion o alien species, 644
p e en ing he in oduc ion and es ablishmen o p io i y in asi e alien species, educing he a es o 645
in oduc ion and es ablishmen o o he known o po en ial in asi e alien species by a leas 50 pe 646
cen , by 2030, e adica ing o con olling in asi e alien species especially in p io i y si es, such as 647
islands. 648
Gi en he iming o he inalisa ion o he a ge , his epo does no explici ly add ess hese elemen s, 649
bu no ably he s uc u e o he a ge is b oadly add essed by he indica o amewo k [e.g., he ocus 650
on pa hways, species, and si es; c . Essl e al. (2020)]. The nex comp ehensi e epo will ocus on 651
speci ically epo ing on he a ge . The indica o s o be used o ack p og ess agains a ge 6 a e s ill 652
o be inalised. None heless signi ican p og ess has been made. Fo example, he wo king g oup 653
sTwis “Theo y and Wo k lows o Alien and In asi e Species T acking” 654
(h ps://www.idi .de/en/s wis .h ml) has p oposed h ee indica o s (McGeoch e al. 2021). Ra e o 655
10
In asi e Alien Species Sp ead p o ides modelled a es o ongoing in oduc ions o species based on 656
in asion disco e y and epo ing. Impac Risk es ima es in asi e species impac s on he en i onmen 657
in space and ime and p o ides a basis o na ionally a ge ed p io i iza ion o whe e bes o in es in 658
managemen e o s; and S a us In o ma ion on in asi e alien species acks imp o emen in he 659
essen ial dimensions o in o ma ion needed o guide ele an policy and da a collec ion and in suppo 660
o assessing in asi e species sp ead and impac . Though each o hese needs o be pee - e iewed. The 661
applicabili y o hese indica o s o he Sou h A ica con ex , and how hey ela e o he indica o 662
amewo k used in his epo will be a ocus o u u e epo s. 663
664
17
2.3 Wi hin-coun y pa hway p ominence 802
Wi hin-coun y pa hway p ominence conside s he oppo uni ies a ailable o he mo emen o 803
o ganisms wi hin he coun y, and does no ake in o accoun how many dispe sal e en s hese 804
oppo uni ies esul in. 805
As in p e ious epo s, da a o wi hin-coun y pa hway p ominence we e no a ailable o mos 806
pa hways, and so he indica o could no be popula ed. Howe e , he e we e some appa en gene al 807
ends, and ecen esea ch has p o ided in o ma ion on he in oduc ion oppo uni ies p o ided by 808
some dispe sal pa hways. As discussed abo e, oppo uni ies o in oduc ions o he coun y we e 809
impac ed by he con ols pu in place o educe he sp ead o COVID-19. These con ols also impac ed 810
he oppo uni ies a ailable, h ough some pa hways, o dispe sal wi hin he coun y. Fo example, 811
he decline in he numbe o domes ic ai c a a i als (a decline o ~67%) in he 2020/2021 inancial 812
yea (Figu e S2.19) was simila o ha o in e na ional and egional ai c a a i als (a decline o 74%). 813
Howe e , he e a e a wide ange o pa hways ha c ea e dispe sal oppo uni ies wi hin he coun y, 814
and i is likely ha no all we e impac ed o his ex en . Fu he mo e, hese oppo uni ies a e e u ning 815
o p e-pandemic le els ( o an example see Figu e S2.19). Recen esea ch has highligh ed he la ge 816
ole ha wildli e anching (Taylo e al. 2021), medicinal plan ade and he pe ade (Shi ambu e 817
al. 2022a) a e playing in mo ing o ganisms a ound he coun y. A su ey o pe shops indica ed ha 818
he sou ces o pe s in he ade a e o en local, wi h a leas 40% o he esponden s ob aining hei 819
animals om local sou ces such as animal escues and o he pe shops, o b eeding hem hemsel es 820
(Shi ambu e al. 2022a). Many o he alien plan s in he medicinal plan ade a e also sou ced locally 821
and mo ed a ound he coun y o his pu pose. A su ey o he ade in Gau eng and KwaZulu-Na al 822
showed ha 41% o he plan s o sale we e ha es ed in sou he n A ica, wi h mos o hese plan s 823
being sou ced in KwaZulu-Na al (Williams e al. 2021b). Alien plan s ha e been inco po a ed in o local 824
pha macopoeias no because hey a e used o ea di e en ailmen s han na i e axa, bu as hey 825
a e e sa ile in e ms o hei uses – hey can be used o many pu poses besides medicine – and many 826
ha e been in he coun y o a long ime (Yessou ou e al. 2021, 2022). 827
2.4 Wi hin-coun y dispe sal a es 828
Wi hin-coun y dispe sal a es conside s he numbe o alien axa ha ha e dispe sed wi hin he 829
coun y h ough he pa hways o dispe sal, including bo h axa alien o he coun y, and hose ha 830
a e na i e o he coun y, bu which ha e been in oduced o pa s o he coun y whe e hey a e no 831
na i e [so-called na i e-alien popula ions, see (Nelu ule e al. 2022)]. Da a o wi hin-coun y dispe sal 832
ha e no been colla ed o axa ha a e alien o he coun y, and so he indica o could no be 833

18
popula ed. Howe e , based on he e iewed li e a u e, alien and na i e axa a e dispe sing wi hin he 834
coun y h ough a leas 31 di e en pa hways (70%). 835
O 132 na i e-alien popula ions ha could be ca ego ised wi h con idence, mos we e in en ionally 836
anspo ed o hei new anges (Nelu ule e al. 2023)(Table S2.4), and we e ei he in en ionally 837
eleased (44 popula ions o 25 axa) o escaped om cap i i y and cul i a ion (34 popula ions o 24 838
axa). These in en ionally in oduced na i e-alien popula ions ended o be plan s used o 839
o namen al pu poses (21 popula ions o 16 axa) and mammals in oduced o game a ms (20 840
popula ions o 11 axa). The e ha e also been acciden al in oduc ions o na i e axa, including: 841
insec s, gas opods, amphibians, and ep iles acciden ally anspo ed wi h p oduc s (29 popula ions 842
o 17 axa), especially, plan p oduc s such as nu se y ma e ials; ep iles and ma ine c us acea 843
anspo ed as s owaways on land ehicles and boa s (7 popula ions o 3 axa); and ish ha ha e 844
sp ead h ough in e -basin wa e ans e schemes (8 popula ions o 4 axa). No ably, as i is o en 845
di icul o con iden ly asc ibe an in oduc ion pa hway, and as he na i e anges o species being 846
mo ed a ound a e o en no well ci cumsc ibed, i is expec ed ha he numbe o na i e-alien 847
popula ions asc ibed o he in oduc ion pa hways is likely o be signi ican ly unde es ima ed. This, as 848
well as hei po en ial impac s (see below), means ha he bene i s o managing wi hin-coun y 849
dispe sal a e likely o be much g ea e han sugges ed by cu en obse ed a es o wi hin-coun y 850
dispe sal. 851
In addi ion o he c ea ion o po en ially in asi e na i e-alien popula ions, he wi hin-coun y 852
mo emen o na i e axa can ha e a ious po en ial conce ning impac s, including ha m ul co-853
in oduc ions and he losses in na i e gene ic di e si y. As discussed in sec ion 2.3, wildli e anches 854
a e acili a ing he mo emen o mammals a ound he coun y and, as a consequence, mos o hese 855
anches ha e a leas one na i e-alien popula ion, bu some ha e as many as 14 (Taylo e al. 2021a). 856
The mos equen ly ound axa wi h na i e-alien popula ions on hese anches we e Aepyce os 857
melampus (impala) and T agelaphus angasii (nyala) (Taylo e al. 2021). A ecen gene ic analysis 858
ound ha A ican Swine Fe e Vi us, a con agious and le hal disease o domes ic pigs, is now ound 859
in he sou h o he coun y, beyond he con olled a ea decla ed in 1935 (C aig e al. 2022). The 860
ansloca ion o li e Phacochoe us a icanus (wa hogs) o game a ms and na u e ese es ou side o 861
hei his o ical ange has likely played a ole in he dispe sal o he i us (C aig e al. 2022). Simila ly, 862
a phylogeog aphic analysis o Xenopus lae is (A ican clawed og) and i s monogenean pa asi e 863
P o opolys oma xenopodis indica ed ha human-media ed ansloca ions o X. lae is had led o 864
di e en lineages o he species coming in o con ac (Schoeman e al. 2022). Bulk expo s o X. lae is 865
om he sou h-wes e n pa o he coun y o u ban cen es in he no h o esea ch and eaching, 866
wi h subsequen escapes, ha e likely played a ole (Schoeman e al. 2022). Bu , X. lae is is also used 867
19
as bai by ec ea ional angle s, wi h angle s ei he collec ing ogs o buying hem om pe shops o 868
b eede s o his pu pose, and while some o hese indi iduals escape, angle s also in en ionally s ock 869
wa e bodies o u u e use, and elease su plus bai . The e o e, i is likely ha h ough ec ea ional 870
ishing indi iduals o di e en lineages a e being mo ed o emo e a eas (Schoeman e al. 2022). 871
In e ms o he wi hin-coun y dispe sal o axa ha a e alien o he coun y, new esea ch has shown 872
ha people and ehicles a e acciden ally dispe sing hese o ganisms o he coun y’s p o ec ed a eas, 873
and ha while he in en ional mo emen o axa a ound by coun y is impo an , na u al dispe sal 874
mechanisms, like zoocho y, a e also playing a ole a he na ional le el. Ma e ials aken om he shoes 875
o ail unne s aking pa in aces in he Ga den Rou e Na ional Pa k we e ound o con ain he seeds 876
o 33 plan species, o which 18 (55%) we e alien o he coun y, and wo we e na i e o he coun y, 877
bu alien o he Ga den Rou e Na ional Pa k (Smi h and K aaij 2020). Along Sani Pass in he Malo i-878
D akensbe g Pa k, exo ic plan axa ha e expanded hei dis ibu ions om lowe o uppe ele a ions, 879
wi h he pa e n o expansion indica ing ha human-aided long-dis ance dispe sal is playing a ole, 880
likely h ough he adhesion o plan p opagules o he shoes o hike s, and ehicles mo ing up he 881
pass (Tu ne e al. 2021). Humans also con inue o in en ionally mo e alien axa a ound he coun y 882
o a ious pu poses, and he wi hin-coun y dispe sal o some axa is being d i en almos en i ely by 883
hese p ocesses. Diopa a acicula a ( he es ua ine moonshine wo m) is a c yp ogenic species ha has 884
expanded i s ange along he coas line, and a i ed in he Knysna Es ua y o he Ga den Rou e Na ional 885
Pa k app oxima ely 15-20 yea s ago ( an Rensbu g e al. 2020). The species is used as bai , and 886
al hough collec ion o en damages he wo ms, in some cases hey can su i e and egene a e. 887
The e o e, new popula ions may a ise when ishe man anspo and disca d le o e bai (Schoeman 888
and Simon 2023). In Sou h A ica asexual ep oduc ion is solely esponsible o he na u al dispe sal 889
o he aqua ic mac ophy e Pon ede ia co da a (Picke el weed) which is sp ead ia hizomes, and hus 890
mos o i s wi hin-coun y dispe sal is likely pe pe ua ed by ga dene s and ho icul u is s ha ade in 891
he axon, and dump plan s and p opagules; and ish a me s and gol cou se owne s ha may be 892
using he axon as a s abilising plan o wa e bodies (Wansell e al. 2022). A Bayesian dynamic species 893
dis ibu ion model ha was used o model he in asion o Plec an hus ba ba us (Abyssinian coleus) 894
in he sou he n Cape showed he in asion o his species was also la gely d i en by human-media ed 895
long-dis ance dispe sal ha o igina ed om he ci ies o i s in oduc ion (Bo ella e al. 2022). 896
Wi hou human-media ed long-dis ance dispe sal, he maximum popula ion size o P. ba ba us would 897
ha e been only 30% o he cu en popula ion size (Bo ella e al. 2022). Na u al p ocesses a e, 898
howe e , playing an impo an ole in he dispe sal o some alien axa. Compa isons be ween alien 899
plan ichness a dump si es and in he p o inces in which he dump si es a e ound, ha e indica ed 900
ha alien plan p opagules a e being dispe sed be ween locali ies in Sou h A ica, wi h he dispe sal 901
20
o some o hese axa likely being acili a ed by omni o ous bi ds ha ly long dis ances (Moko jomela 902
e al. 2022). 903
Box 2.1. Wo k owa ds imp o ing he pa hways indica o s 904
Meaning ul indica o s a e equi ed, a bo h na ional and in e na ional le els, o p o ide policy-905
ele an in o ma ion on he s a us o biological in asions and hei managemen (Wilson e al. 2018). 906
Howe e , he implemen a ion, o e h ee epo s, o he indica o s used he e o epo on he s a us 907
o pa hways has highligh ed se e al issues. 908
Pa hway amewo ks a e used o classi y simila pa hways in o disc e e ca ego ies. These amewo ks 909
se e a a ie y o pu poses, o example, hey imp o e ou knowledge on biological in asions, and 910
hey can be used o p edic u u e h ea s, in o m managemen , and acili a e epo ing o na ional 911
and in e na ional en i ies (Faulkne e al. 2020). A pa hway amewo k p oposed by he CBD as a global 912
s anda d (CBD 2014) has been se as a global biodi e si y s anda d by he Da win Co e (dwc:pa hway) 913
(G oom e al. 2019). This amewo k (see Figu e 2.2) was de eloped o in o m managemen , and assis 914
coun ies o achie e Aichi Biodi e si y Ta ge 9 o he CBD, speci ically he equi emen o iden i y and 915
manage in oduc ion pa hways (Essl e al. 2015, Scale a e al. 2016). Because o his, he amewo k 916
was inco po a ed in o all o he pa hways indica o s used in his epo , excep o he high-le el 917
indica o ‘Ra e o un egula ed in oduc ion o new species’ (Wilson e al. 2018). Howe e , 918
implemen ing he amewo k in he Sou h A ican con ex has been a challenge ( an Wilgen and 919
Wilson 2018, Zengeya and Wilson 2020), and a numbe o issues ha e been iden i ied, pa icula ly 920
wi h he sub-ca ego ies o he amewo k: (1) he di e ences be ween pa hway sub-ca ego ies a e 921
o en unclea ; (2) he a ailable da a a e o en no de ailed enough o classi ica ion in o he sub-922
ca ego ies (e.g., ho icul u e s o namen al); (3) some pa hways ha a e sub-ca ego ies ha e 923
con ibu ed li le o in oduc ions (e.g., u a ming); (4) impo an pa hways a e no included in he 924
sub-ca ego ies (e.g., medicinal plan ade); and (5) some pa hways ha a e likely o become 925
impo an in u u e canno be classi ied using he amewo k (e.g., in oduc ions wi h an h opogenic 926
deb is, such as loa ing plas ics) (Faulkne e al. 2020). Fu he mo e, while he amewo k was 927
de eloped o in o m managemen , he e is no e idence ha i does, and he e a e no clea links 928
be ween he sub-ca ego ies and managemen ac ions (Faulkne e al. 2020). Wo k is cu en ly 929
unde way o de elop and es a amewo k ha will mee Sou h A ica’s needs, by acili a ing 930
epo ing a bo h in e na ional and na ional le els, and in o m managemen ; his will be a ea u e o 931
he nex epo . 932
The high-le el indica o ‘Ra e o un egula ed in oduc ion o new species’ is based on he obse ed 933
a e o in oduc ions (Wilson e al. 2018). Howe e , his is well known o be a biased me ic ha can 934
21
lead o misleading pa e ns. A axon ecen ly eco ded o he i s ime in he coun y, could ha e 935
been in he coun y o many decades (Box Figu e 2.1), and his eco ding delay will impac he a e 936
o in oduc ion i es ima ed based on aw in oduc ion eco ds. As such a cons an a e o in oduc ion 937
wi h a cons an and impe ec de ec ion a e will lead o an accele a ing obse ed a e o in oduc ion 938
(Solow and Cos ello 2004, Belmake e al. 2009). The e o e, es ima es o in oduc ion a es mus 939
conside he a e o disco e y, which is o en unknown. To add ess his, an indica o ‘Ra e o In asi e 940
Alien Species Sp ead’ has been de eloped h ough he sTWIST p ojec [c . Box 1.2; and he p ep in by 941
(McGeoch e al. 2021)]. Mo eo e , Ta ge 6 o he Kunming Mon eal Global Biodi e si y F amewo k 942
(Box 1.1) has a p oposed headline indica o ‘Numbe o In asi e Alien Species In oduc ion E en s’. 943
The nex epo will pilo hese app oaches o ob ain unbiased es ima es o in oduc ion a es in line 944
wi h he CBD's global biodi e si y amewo k. 945
946
Box Figu e 2.1 Examples o alien axa in Sou h A ica ha we e i s eco ded many yea s a e hey 947
a e belie ed o ha e been in oduced. A) Anisolabis ma i ima ( he ma i ime ea wig), was i s eco ded 948
in Sou h A ica in 2015, bu may ha e been in he coun y o mo e han a cen u y (G i i hs 2018). B) 949
Ra us anezumi ( he Asian house a ) was no belie ed o be in Sou h A ica, un il 2005 when i was 950
iden i ied du ing ou ine gene ic moni o ing (Bas os e al. 2005, 2011). The species is ound in mul iple 951
p o inces, and i s in asion may ha e gone unno iced o qui e some ime, due o i s mo phological 952
simila i y o he Ra us a us (black a ) (Bas os e al. 2011). C) Euwallacea o nica es ( he 953
polyphagous sho hole bo e ) was i s eco ded in Pie e ma i zbu g in 2017, bu a DNA sequence o 954
he species was ob ained om a specimen in Du ban in 2012 as pa o he Ba code o Li e p ojec 955
(S ou hame e al. 2017). 956
22
2.5 T ends in pa hway indica o s 957
Indica o
T end1
Con idence
Desi ed end
Cu en s a us and end
Ou look
1. In oduc ion
pa hway
p ominence
→ medium no applicable
13 in oduc ion pa hways play a majo ole
socio-economically.
The e ha e been ew quali a i e changes o his
du ing he pe iod 2020–2022 despi e empo a y
quan i a i e educ ions due o COVID-19
esponse measu es. Fo wo pa hways
in oduc ion pa hway p ominence was
es ima ed o he i s ime.
The ade and a el con ols pu in place o p e en he
sp ead o COVID-19 caused a empo a y decline in some
in oduc ion oppo uni ies, bu hese in oduc ion
oppo uni ies a e e u ning o p e-pandemic le els and
ends. The e is a con inuing need o ack ends in a el
and ade and o in e en ions o espond o such changes
o he wise new ha m ul alien species will con inue o be
in oduced. I , howe e , e ec i e biosecu i y measu es a e in
place, he new biological in asions caused by inc eases in
a el and ade will be educed.
2. In oduc ion
a es → Low
no applicable
( o egula ed
axa)
↘
( o
un egula ed
axa)
Fo egula ed axa: du ing 2020–2022, six new
axa we e legally in oduced o biological
con ol, and one axon ha was al eady in he
coun y was legally in oduced o o he
pu poses.
Fo un egula ed axa: du ing 2020–2022, one
new axon was acciden ally in oduced as a
con aminan o nu se y ma e ials, and wo new
axa we e in oduced o o namen al o
ag icul u al pu poses, o o s abilise soil.
Howe e , se e al axa in oduced and eco ded
p io o 2020 we e epo ed o he i s ime
du ing 2020–2022. As such he e is no s ong
e idence ha ac ual in oduc ion a es ha e
changed o e he pas ew decades.
In many cases egula ed axa ( o which he isks ha e been
analysed and ound o be accep able) a e expec ed o be a
ne bene i o he coun y, and in he case o biological
con ol, assis wi h he con ol o biological in asions.
S ingen p ocesses a e in place o minimise he isk ha such
in oduc ions esul in ha m ul in asions (sec ion 5.1. in
Chap e 5).
Unless pa hways a e iden i ied, p io i ised and managed,
po en ially ha m ul alien axa will con inue o be acciden ally
and illegally in oduced; and speci ically, unless biosecu i y
imp o es, he a e o in oduc ion o un egula ed axa will be
a unc ion o he olume o ade and a el. Howe e
es ima ed a es o in oduc ion a e sensi i e o sea ch e o
and he e is o en a delay o se e al yea s be ween
in oduc ions happening and hem being o mally eco ded
(Box 2.1). New me hods and app oaches a e needed o
ensu e ha es ima es o a es o un egula ed in oduc ion
a e esponsi e and can be used o e alua e he e ec i eness
o in e en ions.
1→ no change; ↗ an inc ease; ↘ a dec ease

23
Indica o
T end1
Con idence
Desi ed end
Cu en s a us and end
Ou look
3. Wi hin-
coun y
pa hway
p ominence
no assessed no applicable
In o ma ion was only ob ained o a ew
pa hways. Many pa hways a e likely playing a
ole socio-economically wi hin he coun y, bu
he ex en o his ole and how i has changed
ecen ly is no known. Res ic ions on wi hin-
coun y ade and a el o p e en he sp ead
o COVID-19 had a sho - e m impac on he
wi hin-coun y dispe sal oppo uni ies p o ided
by some pa hways.
In e nal ade and anspo a e expec ed o inc ease o e
ime. T ends in hese pa hways need o be acked o ensu e
in e en ions a e in place whe e hey a e needed. I his is
no done ha m ul axa will con inue o sp ead, na i e axa
will be in oduced and possibly cause impac s in pa s o he
coun y whe e hey a e no na i e, and aluable asse s will
be pu a isk.
4. Wi hin-
coun y
dispe sal a es
no assessed
no applicable
( o egula ed
axa)
↘
( o
un egula ed
axa)
Alien and na i e axa a e dispe sing wi hin he
coun y h ough a leas 31 di e en pa hways.
Na ional-scale da a ha e ye o be colla ed o
alien axa, bu in o ma ion has become
a ailable o na i e-alien popula ions. Mos
eco ded na i e-alien popula ions a e plan s
in oduced o ho icul u e, o mammals o
aes he ics. Bu na i e-alien popula ions a e also
he esul o acciden al in oduc ions, o
example, o ganisms mo ed wi h anspo ed
plan s o plan p oduc s, o ha dispe se
h ough in e -basin wa e ans e schemes.
Alien o ganisms a e being in oduced, o en
acciden ally, o p o ec ed a eas, and while
human-aided dispe sal is d i ing he dispe sal o
some axa, na u al p ocesses a e also playing an
impo an ole a a na ional scale.
Unless pa hways ha acili a e he wi hin-coun y dispe sal
o axa a e iden i ied, p io i ised, and managed, he sp ead o
hese axa will inc ease, and so he e will be inc eases in bo h
he a e o expansion o cu en ly in asi e axa, and in he
likelihood ha alien axa will ind a sui able pa o he
coun y in which o become in asi e.
Na i e-alien popula ions likely di e in hei impac s o o he
alien popula ions, and o in o m managemen , he e is a
need o imp o e ou unde s anding o he ex en o his
p oblem, and how hese popula ions a e being in oduced;
no ing ha egula ion migh be needed below he na ional
le el.
High le el
indica o
A. Ra e o
un egula ed
in oduc ion o
new species
→ low ↘
O e he las decade (2013–2022)
app oxima ely h ee new axa we e in oduced
pe yea ei he acciden ally o in en ionally bu
illegally. This is simila o p e ious es ima es.
Oppo uni ies o he in oduc ion o alien axa a e expec ed
o inc ease as he olume o ade and a el inc eases.
Whe he his esul s in he in oduc ion o mo e in asi e axa
will depend on he deg ee o which key pa hways a e
iden i ied, p io i ised, and managed. Imp o emen s o
inspec ion, managemen , and incu sion esponse a -bo de
would s eng hen Sou h A ica’s biosecu i y. See chap e 5
o de ails on some posi i e de elopmen s on his on .
958
24
Chap e 3: Species 959
Lead au ho s: Tsungai A. Zengeya, Ka elyn T. Faulkne , Lau a Fe nández Winze , Sab ina Kumschick, 960
Siyasanga Miza, Emily J. McCulloch-Jones, John R. Wilson 961
Con ibu ing au ho s: A iwe Si uba, Whi ney Engelb ech 962
Key indings o species 963
• Sou h A ica is a ho spo o plan in asions wi h se e al eshwa e ishes also causing 964
signi ican nega i e impac s on biodi e si y. P elimina y indings indica e 13 plan s, i e 965
eshwa e ishes, one in e eb a e ha e had Majo o Massi e impac s (as pe he IUCN’s 966
EICAT scheme). Howe e , as only ew axa (38) ha e been o mally assessed, and so his 967
numbe is expec ed o inc ease. 968
• The p ocess o documen ing and acking changes in he s a us o alien species has been 969
subs an ially imp o ed h ough he de elopmen o wo k lows o ensu e wo k is p ope ly 970
documen ed and epea able. This will acili a e acking o alien species o e ime and can 971
eed in o managemen planning and acili a e egula o y decisions. 972
• The numbe o dis ibu ion eco ds om ci izen science pla o ms has subs an ially inc eased 973
he knowledge o he dis ibu ion o some alien axa, bu a decline in ecen ac i e su eillance 974
a leas o plan s (i.e., hia us in he sou he n A ican Plan In ade s A las) ep esen s a 975
signi ican educ ion in he abili y o sys ema ically e alua e ends in in asions o e ime. 976
• The majo i y o alien species a e localised and only a ew we e widesp ead. Howe e , he 977
po en ial o sp ead is la ge and he ex en o mos species will con inue o inc ease unless 978
e ec i e con ol is pu in place. 979
• The phenomenon o na i e-alien popula ions (i.e., axa which a e na i e o a pa o Sou h 980
A ica bu ha e been in oduced o and na u alised in pa s o Sou h A ica o which hey a e 981
no na i e) has been ci cumsc ibed and quan i ied o he i s ime, 77 na i e axa ha e 982
o med 132 na i e-alien popula ions. P e en ing such in asions will equi e a g ea e ocus on 983
managing species mo emen s wi hin he coun y. 984
Key gaps o species and si es1
985
• Da a on he dis ibu ion and abundance o alien species need o be collec ed, colla ed, and 986
in eg a ed in o na ional and global da abases o acili a e he planning o in e en ions. 987
1The gaps lis ed a e he same as in he second epo as he si ua�on has no changed
25
• The sys ema ic quan i ica ion o he impac s o biological in asions would: acili a e he 988
p io i isa ion o in e en ions a ge ing pa icula species and pa icula si es; p o ide he 989
jus i ica ion o go e nmen in es men o con ol biological in asions; and p o ide impo an 990
backg ound o communica e he issue o socie y. 991
Indica o s co e ed in he species chap e 992
993
3.1 Numbe and s a us o alien species 994
A o al o 5121 axa we e assessed o p esence in Sou h A ica o which 3189 axa a e p esen , he 995
p esence o 1197 axa is doub ul, and 735 a e absen 1 (Table 3.1, S3.1). O e hal o he alien axa 996
eco ded as p esen we e plan s, in line wi h he iew ha Sou h A ica is a ho spo o plan in asions 997
and ela i ely (compa ed o o he egions) less a ec ed by animal in asions ( an Wilgen e al 2020). 998
Table 3.1 The numbe o alien species p esen o possibly p esen in Sou h A ica o which 999
in o ma ion has been o mally colla ed as a Decembe 2022. Fo mo e de ails, including axa assessed 1000
and sco ed as absen , see Table S3.2 and Appendix 2. 1001
Taxa
Doub ul
P esen
Bac e ia
0
3
Ch omis a
1
15
Fungi
8
104
In e eb a es
231
952
Plan ae
843
1633
Ve eb a es
114
482
1002
Fo each axon eco ded as p esen he e idence is clea ly speci ied in Appendix 2 and he names ha e 1003
been checked agains a ious axonomic sou ces. Howe e , he lis is no comp ehensi e. The 1004
p esence o many alien axa needs o be con i med and documen ed; many da a sou ces s ill need o 1005
be inco po a ed in o he lis ; and i is likely ha many alien axa ha e no , as ye , been eco ded (see 1006
supplemen a y ma e ial S3.2 o u he de ails on p og ess made o upda e he lis ). In pa icula , 1007
1The as majo i y o axa alien o Sou h A ica ha e ne e been in oduced. Fo example, assuming he e a e
~350,000 ascula plan s alien o Sou h A ica, he s a us o <1% o hese has been o mally assessed in his
epo . Mos axa assessed and ound o be absen we e assessed as hey we e lis ed as p ohibi ed unde he
A&IS Regula ions o 2014 o 2016 (see Sec ion 1.2).
5. Numbe and s a us o alien species
6. Ex en o alien species
7. Abundance o alien species
SPECIES
8. Impac o alien species
HIGH LEVEL
B. Numbe o in asi e species ha
ha e majo impac s
26
many alien axa in cap i i y o cul i a ion a e no included; pa icula axonomic g oups ha ha e no , 1008
ye , been sys ema ically inco po a ed in o he lis s (e.g., well o e hal o 200 o he mos common 1009
mush ooms seen in Sou h A ica a e likely o be alien; c . Goldman & G yzenhou , 2019); and, as no ed 1010
in p e ious epo s, ocussed esea ch e o will o en iden i y many new alien axa (e.g., Magona e 1011
al. 2018). Gi en his is a e ised p ocess, and ha subs an i e and sys ema ic gaps emain in e ms o 1012
colla ing a ailable in o ma ion, i is no meaning ul o compa e alues wi h he p e ious epo o o 1013
an upda ed baseline. 1014
3.2 Ex en o alien species 1015
Occu ence da a we e upda ed based on da a published by he Global Biodi e si y In o ma ion Facili y 1016
(GBIF) and we e only a ailable o a ew axa. As in p e ious epo s a ew axa a e widesp ead 1017
in ade s, bu many alien axa a e only known om a ew si es (Figu e. 3.1). The in eg a ion be ween 1018
he widely used ci izen science pla o m iNa u alis and GBIF means ha he low o in o ma ion om 1019
obse a ions o inco po a ion in o his epo has imp o ed signi ican ly. Howe e , he sou he n 1020
A ican Plan In ade s A las (SAPIA) was pu on a hia us in he i s qua e o 2020. SAPIA p o ided 1021
s anda dised da a on he dis ibu ion o alien plan s h ough colla ing submissions om expe s 1022
(which can now occu ia iNa u alis , hough wi h di e en quali y con ol p ocedu es) and h ough 1023
dedica ed oad-side su eys ac oss he coun y (which is no longe happening). The ac i e su eillance 1024
e o o SAPIA allowed o ends in he ex en o plan in asions o be eliably e alua ed o e ime 1025
(c . Hende son and Wilson, 2017); he loss o his moni o ing ep esen s a signi ican decline in he 1026
abili y o Sou h A ica o ack plan in asions. The use o emo e sensing echniques con inues o 1027
p omise much o add ess some o hese issues, bu emo e sensing has i s own limi a ions, and 1028
sys ema ic, epea able in o ma ion o he ype equi e o ack in asions o e ime a e no ye 1029
a ailable. 1030
33
Chap e 4: Si es1 1111
Lead au ho s: Tsungai Zengeya; Emily J. McCulloch-Jones; B ian W. an Wilgen 1112
Con ibu ing au ho s: bc 1113
Key indings o si es 1114
To be added (c . key indings on Chap e 3: Species) 1115
Key gaps o species and si es2 1116
• Da a on he dis ibu ion and abundance o alien species need o be collec ed, colla ed, and 1117
in eg a ed in o na ional and global da abases o acili a e he planning o in e en ions. 1118
• The sys ema ic quan i ica ion o he impac s o biological in asions would: acili a e he 1119
p io i isa ion o in e en ions a ge ing pa icula species and pa icula si es; p o ide he 1120
jus i ica ion o go e nmen in es men o con ol biological in asions; and p o ide impo an 1121
backg ound o communica e he issue o socie y. 1122
Indica o s co e ed in he si es chap e 1123
1124
4.1 Alien species ichness 1125
Comp ehensi e es ima es o alien species ichness a e limi ed o small a eas and o pa icula axa 1126
(e.g., McLean e al. 2018, Baa d and K aaij 2019; Cheney e al. 2019). The e o e, b oad-scale species 1127
ichness es ima es can only be eliably es ima ed o in asi e species. In asi e species a e dis ibu ed 1128
ac oss he coun y, wi h mos b oad-scale adminis a i e uni s and biogeog aphical egions being 1129
in aded by a a ie y o axa (Table 4.1). 1130
A a p o incial scale, he e has been minimal change in alien species ichness. Mos alien species a e 1131
ound in he Wes e n Cape, Eas e n Cape, and KwaZulu-Na al (Figu e 4.1A). The mos p ominen 1132
inc ease in he numbe o alien species pe p o ince was in he Wes e n Cape (128 species) and he e 1133
we e mode a e (29–84 species) o low (1–28 species) inc eases in alien species ichness in he o he 1134
1No all a ailable in o ma ion o upda e he indica o alues o all he species lis ed in Appendix 2 has been
cap u ed ye , and he ma e ial p esen ed in his d a is based on an analysis o incomple e in o ma ion. In he
inal epo , upda es will be d awn o all axa whe e da a a e a ailable.
2The gaps lis ed a e he same as in he second epo as he si ua ion has no changed.
SITES
9. Alien species ichness
10. Rela i e in asi e abundance
11. Impac o in asions
HIGH LEVEL
C. Ex en o a ea ha su e s majo
impac s om in asions

34
p o inces (Figu e 4.1B). Gi en he na u e o he da a sou ces i is likely ha hese pa e ns a e la gely 1135
a esul o changes in eco ds on iNa u alis eeding h ough o GBIF. 1136
A a ine scale, only 7% (120 ou o 1673 qua e -deg ee g id cells) had 50 o mo e alien species. The 1137
eco ded alien species ichness appea s o be highes a ound majo u ban cen es (Figu e 4.1C). As 1138
p e iously no ed, his is likely because some species a e commensal wi h humans, mos we e i s 1139
in oduced o u ban cen es, and because o g ea e sampling a ound u ban a eas. This is pa ly 1140
e lec ed in he no able inc eases in alien species ichness a ound u ban a eas p ima ily om 1141
inc eased obse a ion om he ci izen scien is pla o ms such iNa u alis (Figu e 4.1D). 1142
In o ma ion on alien species ichness was a ailable o SANPa ks and Cape Na u e p o ec ed a eas 1143
(Table 4.1E). 1 014 in asi e species (excluding biocon ol agen s and ma ine species) a e epo ed o 1144
occu ac oss he SANPa ks es a e. O hese, he e a e 256 animal species and 758 plan species. 333 1145
o hese axa a e lis ed unde he A&IS Regula ions, he emaining 681 species a e unlis ed. No 1146
p o ec ed a ea complex is alien- ee. Th ee p o ec ed a eas (Ga den Rou e NP, K uge NP, and Table 1147
Moun ain NP) had mo e han 100 in asi e species. In 2022, Cape Na u e lis ed 759 in asi e species 1148
ac oss hei es a e o 31 p o ec ed a ea clus e s. The numbe o in asi e species included 502 plan s 1149
and 257 animals o which 404 a e lis ed unde he A&IS Regula ions. No p o ec ed a ea complex is 1150
ee o in asi e species, bu he dis ibu ion o in asi es be ween p o ec ed a eas is highly skewed 1151
wi h only ou p o ec ed a eas epo ing mo e han 40 in asi e species. 1152
Table 4.1. In asi e species ichness in Sou h A ica o di e en b oad-scale adminis a i e uni s and 1153
biogeog aphical egions1. The es ima es o change a e made wi h low con idence because mos 1154
epo ed inc eases a ise om he o mal eco ding o species ha ha e p obably been p esen o 1155
some ime. Da a a e o Sou h A ican eco ds a ailable om GBIF (h ps://www.gbi .o g/) and he
1156
sou he n A ican Plan In ade s A las (SAPIA) o con inen al Sou h A ica, om Robinson e al. (2020) 1157
o ma ine eco- egions. NA = no assessed. Fu he de ails will be p o ided in supplemen a y ma e ial, 1158
see Appendix 1 o he da a sou ces, and Appendix 2 o he ull species lis . In o ma ion on he P ince 1159
Edwa d Islands is p esen ed in Chap e 6 and he accompanying appendices and supplemen a y 1160
ma e ial. 1161
A) In asi e e es ial species and in asi e eshwa e plan species ichness pe p o ince. 1162
P o ince / Region
End o 2019
End o 2022
Change
Eas e n Cape
148
F ee S a e
88
Gau eng
133
KwaZulu-Na al
184
Limpopo
106
Mpumalanga
210
No he n Cape
64
No h Wes
81
1 Tables s ill o be upda ed
35
P o ince / Region
End o 2019
End o 2022
Change
Wes e n Cape
186
B) In asi e e es ial species and in asi e eshwa e plan species ichness pe biome. 1163
Biome
End o 2019
End o 2022
Change
Albany Thicke
108
Dese
9
Fynbos
251
Fo es
10
G assland
230
Indian Ocean Coas al Bel
156
Nama-Ka oo
76
Sa anna
241
Succulen Ka oo
55
C) In asi e eshwa e animal species ichness pe wa e managemen a ea. 1164
Wa e managemen a ea
End o 2019
End o 2022
Change
A-Limpopo
4
B-Oli an s No h
2
C-Vaal
2
D-O ange
3
E-Oli an s Wes
2
F-Bu els
0
G-Be g
3
H-B eede
1
J-Gou i z
1
K-K om
2
L-Gam oos
2
M-Swa kops
2
N-Sundays
1
P-Bushmans
0
Q-G ea Fish
2
R-Keiskamma
2
S-Kei
4
T-Mzim ubu
2
U-Mkomazi
2
V-Tugela
4
W-M olozi
3
X-Koma i
4
D) Ma ine in asi e species ichness pe ma ine eco egion. 1165
Ma ine eco egion
End o 2019
End o 2022
Change
Agulhas
41
Na al
25
Delagoa
8
Sou he n Benguela
39
Sou heas A lan ic (o sho e)
0
Sou hwes Indian (o sho e)
0
E) In asi e species in p o ec ed a eas in Sou h A ica. 1166
36
In asi e
species
ichness
Cape Na u e
SANPa ks
End o
2019
Augus
2021
Change
End o
2019
End o
2022
Change
0
0
0
0
1–10
3
0
0
10–20
10
6
6
21–30
4
3
3
31–40
10
4
4
41–50
3
1
1
>50
1
6
6
1167
4.2 Rela i e in asi e abundance 1168
The e a e no coun y-wide es ima es o he ela i e abundance o in asi e species, bu he e a e 1169
es ima es o in asi e plan s in p o ec ed a eas managed by he Sou h A ican Na ional Pa ks, 1170
Ezem elo KwaZulu-Na al Wildli e and Cape Na u e. Es ima es o ela i e in asi e abundance in hese 1171
p o ec ed a eas om 2019 indica ed ha in asions we e mino o mode a e (Table 4.2). The es ima es 1172
o p o ec ed a eas managed by Cape Na u e ha e no changed be ween 2019 and 2022. 1173
Table 4.2. Es ima es o ela i e in asi e abundance in Sou h A ica`s p o ec ed a eas based on 1174
pe cen age plan co e . Alien- ee means ha no alien species a e eco ded in he p o ec ed a ea1. 1175
Rela i e in asi e
abundance
Numbe o Cape Na u e`s
p o ec ed a eas
Numbe o Ezem elo
KwaZulu-Na al Wildli e`s
p o ec ed a eas
Numbe o SANPa ks
p o ec ed a eas
2018
2021
2019
2022
2019
2022
Alien- ee
0
0
1
0
Mino <2%
12
11
59
14
Mode a e 2-10%
5
7
39
2
Ex ensi e 10-50%
12
11
22
0
Dominan >50%
0
0
0
0
1176
1 his will be upda ed in he inal epo
37
1177
1178
Figu e 4.1. Alien species ichness in Sou h A ica pe A) p o ince and C) qua e -deg ee g id cell as o Decembe 2022 based on occu ence eco ds om 1179
GBIF and SAPIA, and B), D) he change in hese alues since Decembe 2019. Da a om GBIF. In he inal epo , hese pa e ns a e o be placed in he 1180
including in he con ex o S a egic Wa e Sou ces A eas (SWSAs).1181
38
4.3 Impac o in asions1 1182
E alua ions on impac a e o en piecemeal o augh wi h majo assump ions. In 2008, an Wilgen e 1183
al. (2008) pe o med a biome-scale assessmen o he impac o in asi e plan s on ecosys em se ices 1184
in Sou h A ica. This s udy has been pi o al in ou unde s anding o he impac s o in asi e plan s 1185
(in asi e ees in pa icula ) in Sou h A ica bu has since no been e ised o eassessed. We in end 1186
o eplica e he an Wilgen e al. (2008) s udy and de elop wo k lows (sensu Seebens e al. 2022) o 1187
imp o e he applicabili y and epea abili y o he me hods. The p ocess is in ended o help iden i y 1188
gaps in he s udy, and aspec s o he me hods ha could bene i om upda ed da a sou ces and ecen 1189
modelling echniques. Ul ima ely, he wo k low would p o ide a syn hesised, ep oducible, and 1190
anspa en me hod ha can be used o assess he impac s o in asi e plan species o e ime. I 1191
should be no ed ha pa icula ocus will be gi en o he impac s o in asi e ees on wa e esou ces 1192
in Sou h A ica. The me ic used o communica e his impac o e ime has a ied g ea ly and we 1193
u he in end o iden i y a s anda d me ic ha can be used o exp ess impac o allow o con inued 1194
compa isons. 1195
Box 4.1 Es ima ing he cos s o in asions o Sou h A ica 1196
In asi e species a ec ecosys em unc ioning and hinde he deli e y o ecosys em se ices, o en 1197
leading o signi ican economic losses (Vaissiè e e al. 2022). His o ically, he economic impac s o 1198
biological in asions (in e ms o damage and managemen cos s), ha e been poo ly ep esen ed in he 1199
li e a u e and es ima es a e gene ally un eliable as hey a e augh wi h majo assump ions (Cu hbe 1200
e al. 2020). In an a emp o s anda dise es ima e o economic impac s o in asions a na ional and 1201
global scales, Diagne e al. (2020b) de eloped In aCos . In aCos is a global-scale da a eposi o y o 1202
in o ma ion on economic cos s associa ed wi h biological in asions om pee - e iewed o g ey 1203
li e a u e. In aCos s udies ha e o da e been comple ed o a ange o ocal opics, including, 1204
syn hesis a global and na ional scales and o a ious axonomic g oupings (Zenni e al. 2021; and o 1205
an upda ed lis o In aCos s udies see h ps://in acos . /en/ou comes/). 1206
As pa o his epo , an In aCos - ype analysis was conduc ed o Sou h A ica. Da a we e ob ained 1207
om 67 sou ce documen s ha we e published in he pe iod 1960–2023. The obse ed cos o 1208
damage was ZAR49.2 billion (adjus ed o 2021 alues) wi h p edic ed damages a ZAR178.8 billion. In 1209
con as , he money spen on con ol was only ZAR8.6 billion, wi h p edic ed managemen cos s a 1210
1ongoing wo k includes he de elopmen o sys ema ic p ocesses o e alua ing impac s udies and wo k- lows
including ways o scaling up; link o o he biodi e si y assessmen s such as he Na ional Biodi e si y Assessmen
(NBA) and p e ious s udies ha looked a he impac s on biodi e si y, wa e , and g azing (e.g. an Wilgen e al.
2008)

39
ZAR 377.7 billion. Thus, es ima es o damage cos a e signi ican ly g ea e han es ima es o 1211
managemen ; and he p edic ions o money spen needed o each managemen h esholds we e 1212
consis en ly an o de o magni ude highe han ac ual money spen . 1213
1214
Box Figu e 4.1 Es ima es o he ela i e cos o in asions and money spen on managemen o 1215
a ious axa (unpublished da a, upda ed o May 2023). 1216
Plan s accoun ed o he majo i y o cos s, howe e a ew axa and a ew s udies accoun ed o almos 1217
all o hese es ima es. Fo example, 63 % o all obse ed damage cos s a e a ibu able o Acacia 1218
mea nsii; and 73% o p edic ed managemen cos s and 99% o cos s due o animals we e a ibu ed 1219
o a hand ul o s udies on he ecen in asions by Euwallacea o nica us ( he polyphagous sho hole 1220
bo e ) and i s ungal symbion . Simila ly, he e a e subs an i e skews in he a ailabili y o in o ma ion 1221
on he money spen con olling biological in asions. Va ious s akeholde s a e known o spend money 1222
con olling biological in asions (see Table 5.1), bu only o he Wo king o Wa e p og amme was an 1223
almos comple e da a on expendi u e a ailable. None heless, he da a colla ed as pa o his exe cise 1224
ep esen s a majo imp o emen in he anspa ency and accessibili y o da a ela ed o he money 1225
spen on and es ima ed damage caused by biological in asions. 1226
1227
Managemen
Obse ed Damage
Di e se Animal
Bi ds
C abs
Fishes
Insec s
Snails/ Slugs
Di e se Plan s
Aqua ic Plan s
Cac i/ Succulen s
In asi e T ees
Sh ubs/ He bs
Vines/ C eepe s
G asses/ Reeds
Mixed Taxa
40
4.4 T ends in si es indica o s 1228
Indica o
T end1
Con idence
Desi ed end
Cu en s a us
Ou look
9. Alien
species
ichness
↗ low
↘
( o in asi e
species)
Inc ease in ex en we e seen in
a ious p o inces (pa icula he
Wes e n Cape), al hough wi hou
ac i e su eillance his migh be
an a e ac o mo e eco ds being
submi ed o he ci izen science
pla o m iNa u alis .
The de elopmen o a obus and eliable moni o ing me hodology should be
seen as a p io i y, because in he absence o eliable in o ma ion on species
ichness and ela i e abundance, nei he he magni ude o impac s no he
e ec i eness o managemen can be p ope ly assessed.
10. Rela i e
in asi e
abundance
→ low ↘
Es ima es we e only a ailable o
da e o one g oups o p o ec ed
a eas. The e ha e been no majo
changes in he ela i e abundance
o in asi e plan s in Cape Na u e
p o ec ed a eas.
Achie ing consis ency in acking ela i e abundance in p o ec ed a eas could be
acili a ed by he inclusion o a s anda dised moni o ing p o ocol in he c i e ia
o he p epa a ion o managemen plans which we e de eloped by he DFFE in
e ms o he A&IS Regula ions. I is expec ed ha exis ing in asions will densi y
unless managed. The cos s o con ol and he impac s caused o en inc ease
d ama ically wi h he le el o in asion.
11. Impac s o
in asions no eassessed ye ↘ no eassessed ye
Impac s a e likely o inc ease as in asi e species con inue o sp ead, and as
con ol e o s a e scaled back in esponse o iscal cons ain s. This unde sco es
he impo ance o e- ocussing con ol e o s on ag eed p io i y si es, and
aking s eps o imp o e con ol e ec i eness. Impac s o in asions on si es ha e
been quan i ied using di e en app oaches and me ics o e ime and i is no
ye possible o compa e alues wi h p e ious epo .
High le el
indica o
C. Ex en o
a eas ha
su e majo
impac s om
in asions
no eassessed ye ↘ no eassessed ye
I con ol e o s ocus on p io i y si es (e.g., si es ha p o ide wa e o Cape
Town’s dams) hen he e will be signi ican e u ns on in es men . Howe e ,
wi hou ag eemen on p io i ies, he e is a subs an ial isk ha con ol could
emain ine ec i e, and he a ea ha su e s om majo impac s will con inue o
g ow. Es ima es o he ull magni ude o impac s equi e mo e accu a e
assessmen s o he ex en o in asions. This, in u n, equi es e ec i e mapping
o he a eas in aded and moni o ing o sp ead. Such moni o ing is cu en ly
lacking, and wi hou which e ec i e p io i isa ion is no possible.
1229
1→ no change; ↗ an inc ease; ↘ a dec ease
41
Chap e 5: In e en ions 1230
Lead au ho s: B ian W. an Wilgen, Ka elyn T. Faulkne , John R. Wilson & Má han Thea 1231
Con ibu ing au ho s: Nicholas Cole, Julie A. Coe zee, Whi ney Engelb ech , Phe ole Manyama, Emily 1232
McCulloch-Jones, Themba Mnguni, Zacha iah Mokganye, Iain Pa e son, Leoni P e o ius, Roge P ice, 1233
Louise S a o d, And ew A. Tu ne , Ka abo Wanjau, And ew Wannenbu gh & Cos as Zacha iades. 1234
Key indings ega ding in e en ions 1235
• The NEM:BA A&IS Regula ions and Lis s we e e ised and p omulga ed in 2020. These 1236
amendmen s a e conside ed o ha e imp o ed he egula o y egime. 1237
• Howe e , he a ionale o changes o he lis s ( he p ohibi ed lis was emo ed and he 1238
lis ings o 73 axa changed) was no documen ed. A p ocess has been se up o ensu e ha 1239
changes o he lis s can be made mo e egula ly, anspa en ly, and in o med by e idence. 1240
• A subs an ial a ea o comme cial o es y has been exemp ed om equi ing pe mi s o 1241
cul i a e and ade in lis ed in asi e ees. As a esul , comme cial o es y emains as an 1242
un egula ed seed sou ce o e-in ading adjacen a eas ha ha e been clea ed. 1243
• A leas ZAR 1.4 billion has been spen on he managemen o biological in asions o e he 1244
pe iod 2020–2022. Howe e , he money spen has declined s eadily in eal e ms since 2015. 1245
• The ecen en y o se e al NGOs who ha e p o ided unding o he con ol o alien ees in 1246
ca chmen a eas, and o in asi e eshwa e ish, is an encou aging de elopmen . 1247
• A lack o adequa e planning emains a cons ain o e ec i e managemen , and a lack o 1248
moni o ing means i is di icul o e alua e he e ec i eness o managemen ha is in place. 1249
• Plans a e assumed o exis o he managemen o 40 o 44 iden i ied in oduc ion pa hways, 1250
al hough no plans ha e been o mally app o ed. The managemen o se en pa hways is 1251
e ec i e and o one pa hway is pa ially e ec i e. Fo he emainde , he e ec i eness o 1252
managemen is ei he unknown (14 pa hways), ine ec i e (17 pa hways), o he e is no 1253
managemen ( i e pa hways). 1254
• 23 species (o which 16 a e egula ed and 7 a e un egula ed) ha e managemen plans in place. 1255
These a e all ac ual o po en ial a ge s o na ional e adica ion. 1256
• Abou one hi d o he 566 egula ed axa ha e ecei ed some o m o ac i e ea men (e.g. 1257
clea ing) o e he pas h ee yea s. Howe e , he e ec i eness o con ol is unknown o mos 1258
o he ea ed species. A ew species we e assessed as being unde pe manen con ol (based 1259
on an assessmen o comple e biological con ol). 39 alien pes s o ag icul u al c ops we e 1260
42
subjec ed o biological con ol, bu only one o hese pes s is lis ed unde he NEM:BA A&IS 1261
Regula ions. The numbe s will be upda ed in he inal epo . 1262
• The a ea co e ed by cu en si e managemen plans has dec eased om 14.7% o 8.2% o he 1263
es ima ed in aded a ea, due o some plans ha ing lapsed. Howe e , he e has been an 1264
imp o emen in he adequacy o planning, wi h plans co e ing 45.1% o he planned a ea 1265
being assessed as adequa e (compa ed o 2% p e iously), and 53.6% as pa ially adequa e 1266
(compa ed o 42% p e iously). 1267
• Con ol ope a ions eached 1% o he es ima ed in aded a ea be ween 2020 and 2022. The e 1268
is e idence ha con ol e o s ha e educed he a ea in aded a some si es, bu mos in asi e 1269
species ha e con inued o expand hei ange when assessed a a na ional scale. 1270
• The Wo king o Wa e p og amme p o ides mo e han 80% o he money known o be spen 1271
on he managemen o biological in asions in Sou h A ica. The exac p opo ion canno be 1272
assessed as mos o he unding epo ed by o he agencies is sou ced om he Wo king o 1273
Wa e p og amme, bu he p opo ion is ypically no epo ed. 1274
• The pauci y o moni o ing o he ou comes o con ol measu es, along wi h he absence o 1275
managemen plans wi h clea goals, emains a subs an ial impedimen o assessing he 1276
e ec i eness o con ol measu es. 1277
Key gaps ega ding in e en ions1 1278
• A comp ehensi e policy, and a s a egy o implemen such a policy, is needed o guide 1279
in e en ions on biological in asions in Sou h A ica. 1280
• The absence o o mal p og ammes o moni o he e ec i eness o in e en ions in e ms o 1281
ou pu s and ou comes means ha he e icacy o con ol canno be demons a ed, con ol 1282
measu es canno be compa ed and imp o ed, and i is no clea whe he p og ess is being 1283
made o educe he nega i e impac s o in asions. 1284
1285
1286
1These key gaps ha e no changed since he second epo .
49
Table 5.1 Money epo ed as ha ing been spen on he managemen o biological in asions in Sou h A ica by di e en o ganisa ions be ween 2020 and 1447
2022. The amoun s a e o alled o h ee yea s, unadjus ed o in la ion. Inpu s om a ious o ganisa ions and many s akeholde s, pa icula ly in he 1448
p i a e sec o , ha e no been included (and so he o e all igu e should be iewed as a lowe es ima e). Howe e , i is also possible ha he e may be some 1449
double coun ing, as some o he money spen by implemen ing agencies may also ha e been epo ed by he Depa men o Fo es y, Fishe ies and he 1450
En i onmen (DFFE)’s Wo king o Wa e P og amme, his is o be add essed in he inal epo . 1451
O ganisa ion
Money spen on
Money spen
(ZAR)
No es
Ag icul u al
Resea ch Council
Biological con ol esea ch
104 495 930
ZAR 69 700 073 om he DFFE and ZAR 34 795 857 om he ARC.
Bu alo Ci y (Eas
London)
P o ec ed a eas wi hin he municipal
bounda ies
9 151 000
This includes o he ac i i ies such as clea ing o ege a ion along oad e ges
Cape Na u e
31 p o ec ed a eas in he Wes e n Cape
P o ince
9 299 189
Mos o his money came om he Wo king o Wa e p og amme and so he e may
be some double coun ing
Cen e o Biological
Con ol, Rhodes
Uni e si y
Biological con ol esea ch and
implemen a ion
82 000 000
ZAR 59 million om Wo king o Wa e ; ZAR 15 million om he DST-NRF ia he
Sou h A ican Resea ch Chai s Ini ia i e; ZAR 8 million om o he sou ces.
The bulk is spen a Rhodes Uni e si y, bu pa o he unding is dis ibu ed o he
Uni e si ies o Cape Town, Wi wa e s and, KwaZulu/Na al, Mpumalanga, and Fo
Ha e
Ci y o Eku huleni
(Gau eng)
Managemen o aqua ic ecosys ems
17 700 000
Funding has been expended mos ly on Pon ede ia c assipes (wa e hyacin h), A undo
donax (gian eed), and Nymphaea mexicana (yellow wa e lily) in ading aqua ic
ecosys ems
Depa men o
Ag icul u e, Land
Re o m and Ru al
De elopmen
Responsible o Conse a ion o
Ag icul u al Resou ces Ac (CARA) and
o he legisla ion. Main ains a p esence a
all bo de pos s.
No es ima e
a ailable
The expendi u e on hese ac i i ies was eques ed om DALRRD bu no inpu was
ecei ed.
DFFE animal con ol
p ojec s
Con ol o in asi e animals
No es ima e
a ailable
The expendi u e on hese ac i i ies was eques ed om DFFE bu no inpu was
ecei ed.
DFFE Biosecu i y
Moni o ing ac i i ies aimed a in e cep ion
o alien species a OR Tambo In e na ional
Ai po
13 820 241
The igu e epo ed he e does no co e he cos s o all o he biosecu i y ac i i ies
unde aken by he DFFE, no does i include depa men al o e heads.

50
O ganisa ion
Money spen on
Money spen
(ZAR)
No es
DFFE high al i ude
eams
Specially ained eams deployed o
con ol in asi e plan s in ela i ely
inaccessible o moun ainous e ain
255 298 699
Budge ed amoun o inancial yea s. The DFFE epo ed an amoun o ZAR 208
237 112, and 22.6% was added o accoun o o e heads ( an Wilgen e al., 2022)
DFFE Na u al
Resou ce
Managemen
p og ammes
(Wo king o Wa e )
App oxima ely 250 p ojec s es ablished o
con ol es ablished in asi e plan s ac oss
all 9 p o inces
470 972 650
This co e s he pe iod 1 Janua y 2020 o 30 Ap il 2022. The DFFE was no able o
supply da a o he pe iod 1 May o 31 Decembe 2022. The DFFE epo ed an amoun
o ZAR 384 153 875, and 22.6% was added o accoun o o e heads ( an Wilgen e
al. 2022).
Funding (including o e heads) can be b oken down in o: ZAR 413 206
893 o
widesp ead alien plan s (See Table 5.2 o a b eakdown by he mos cos ly species);
ZAR 47 812 384 o e adica ion a ge s; ZAR 37 336 449 o na i e bush enc oache s;
and ZAR 10 475 934 o alien aqua ic weeds.
DFFE alue added
indus ies
Es ablishmen and ope a ion o ac o ies
in ended o p oduce a ange o p oduc s
wi h biomass sou ced om alien plan
con ol ope a ions
237 223 158
Budge ed amoun o inancial yea s. The DFFE epo ed an amoun o ZAR 193
493 604, and 22.6% was added o accoun o o e heads ( an Wilgen e al. 2022).
Gau eng p o incial
ese es (No h)
Th ee p o ec ed a eas in he no h o
Gau eng p o ince
6 000
Only includes cos s o he bicide and a pai o scisso s, s a ime no included.
Gau eng p o incial
ese es (Sou h)
Th ee p o ec ed a eas in he sou h o
Gau eng p o ince
2 300 000
In asi e Fish Species
Managemen (IFSM)
Con ol o Cypinus ca pio (common ca p)
in G oen lei lake, Wes e n Cape.
450 000
IFSM is a NGO in he Ga den Rou e. Amoun spen be ween 2018 and 2022 was ZAR
750 000 (es ima e supplied by he di ec o , Johnny Snyman). Assuming an equal
amoun spen each yea , he es ima e o 2020 o 2022 is ZAR 450 000.
Sou h A ican
Na ional Biodi e si y
Ins i u e
P epa a ion o s a us epo s, isk analyses,
incu sion esponse, axonomy, esea ch,
and human capaci y de elopmen
(placemen o in e ns)
145 454 000
Money ob ained on con ac om DFFE
Sou h A ican
Na ional Pa ks
22 na ional pa ks ac oss Sou h A ica, and
ou side o pa ks in bu e zones
3 985 260
SANPa ks epo ed an amoun o ZAR 199 263 000, bu only 2% o his came om he
SANPa ks budge , he es om DFFE Na u al Resou ce Managemen p og ammes
(Wo king o Wa e ).
51
O ganisa ion
Money spen on
Money spen
(ZAR)
No es
The G ea e Cape
Town Wa e Fund
Ca chmen s o he Be g and
Theewa e skloo dams, and A lan is
aqui e , Wes e n Cape P o ince
~100 000 000
Es ima ed amoun p o ided by he p ojec manage
Volun ee g oups
52 olun ee g oups om he Wes e n
Cape who clea in asi e plan s
5 106 241
Da a om Jubase e al. (2021). This is he cu en cos o clea he equi alen a ea
ha has been clea ed by olun ee g oups, some o which ha e been ope a ional
since 1980. A po ion o his amoun may he e o e ha e been spen p io o he
pe iod co e ed by his epo , bu is epo ed he e in ull as i has no been epo ed
be o e.
Wo ldwide Fund o
Na u e Sou h A ica
(WWF-SA)
11 s a egic wa e sou ce a eas in he
Wes e n Cape ynbos ca chmen s, and in
he Eas e n Cape and KwaZulu-Na al
D akensbe g.
26 603 201
Some o his money may be included in he G ea e Cape Town Wa e Fund es ima e.
1452
52
Table 5.2 Money spen clea ing selec ed in asi e plan s in Sou h A ica by he Wo king o Wa e 1453
p og amme. This is o he pe iod 2020 o he end o Ap il 2022. Values include a 22.6% o e head. 1454
Spending on hese axa ep esen abou wo hi ds o all he money disbu sed. 1455
Taxon
Money spen (ZAR)
% o o al cos
Acacia mea nsii
88 634 536
18.8
Lan ana cama a
55 549 985
11.8
Acacia saligna
32 342 218
6.9
Nel uma species and hyb ids
28 605 969
6.1
Acacia melanoxylon
22 182 801
4.7
Acacia dealba a
21 189 774
4.5
Rubus cunei olius
13 391 654
2.8
Pinus pinas e
13 204 338
2.8
Ch omolaena odo a a
12 114 313
2.6
Acacia cyclops
9 079 521
1.9
Psidium guaja a (and possibly o he Psidium spp.)
8 307 475
1.8
Eucalyp us camaldulensis (and possibly o he Eucalyp us spp.)
8 144 657
1.7
1456
5.3 Inpu —planning co e age 1457
Pa hway managemen plans: As epo ed in he p e ious epo , no o mally app o ed managemen 1458
plans o pa hways ha e been de eloped by DFFE, and pa hway managemen plans a e no equi ed 1459
as pe he NEM:BA A&IS egula ions. Howe e , managemen is in place o 39 o 44 pa hways. 1460
The e o e, i is assumed ha plans a e in place o hose pa hways, hough no eco ds o he plans 1461
being o mally app o ed we e a ailable. In addi ion, ballas wa e managemen plans ha e been 1462
de eloped, bu no implemen ed, hus 40 pa hways a e assumed o ha e plans in place (see 1463
supplemen a y ma e ial S5.8). 1464
Species managemen plans: The NEM:BA equi es [Sec ion 75(4)] he Minis e o ensu e he 1465
coo dina ion and implemen a ion o plans (called p og ammes in he Ac ) o he p e en ion, con ol 1466
and e adica ion o in asi e species. No plans ha e been o mally adop ed, al hough, as epo ed 1467
p e iously, plans ha e been p epa ed o wo species (Pa henium hys e ophe us and Campuloclinium 1468
mac ocephalum), wo gene a [Acacia and Nel uma (p e iously P opsopis)] and one amily (Cac aceae) 1469
o in asi e plan s. In addi ion, 23 plans ha e been de eloped o species a ge ed o , o conside ed 1470
o , na ion-wide e adica ion. O he 23 species managemen plans, 13 we e sco ed as adequa e, 8 as 1471
pa ially adequa e and 2 as inadequa e. Mos (16) o hese species a e ca ego y 1a, he es (7) a e no 1472
cu en ly lis ed (see supplemen a y ma e ial S5.10 o how he plans we e sco ed and Table S5.7 o 1473
he lis o axa). 1474
Si e managemen plans: In e ms o he NEM:BA A&IS Regula ions, he esponsibili y o d awing up 1475
si e managemen plans o si es lies wi h indi idual landowne s (s a e o p i a e), because hey a e 1476
esponsible by law o he con ol o lis ed in asi e species on hei land. A da abase has been 1477
53
de eloped o ack planning co e age o si es (see Table 5.4, and supplemen a y ma e ial S5.11). All 1478
plans submi ed o SANBI o he i s h ee s a us epo s we e cap u ed in o his da abase. 1479
In o al, o e he h ee epo ing pe iods o da e, 91 plans co e ing 4.5 million ha ha e been submi ed. 1480
Assuming ha he e is no o e lap, his amoun s o 23% o he es ima ed a ea co e ed by in asions in 1481
Sou h A ica (19.5 million ha, see an Wilgen e al. 2022). O hese, 59 plans co e ing 1.6 million ha a e 1482
conside ed o be cu en (i.e. co e ing 8.2% o he es ima ed in aded a ea), and 32 ha e lapsed, and 1483
a e assumed no o ha e been upda ed. 1484
Cape Na u e, he p o incial au ho i y in he Wes e n Cape P o ince, p o ided he la ges co e age by 1485
submi ing 19 plans co e ing 607 142 ha o p o ec ed a eas unde hei con ol (Figu e 5.1). Plans 1486
submi ed by eigh municipali ies (3% o he 257 municipali ies in he coun y) accoun ed o he nex 1487
la ges a ea (567 329 ha) planned. The only o he conse a ion agencies ha submi ed plans we e 1488
Sou h A ican Na ional Pa ks and p o incial p o ec ed a eas in Gau eng P o ince. Plans we e submi ed 1489
o 3 ou o 19 na ional pa ks in he coun y (Agulhas, Wes Coas and Bon ebok, all in he Wes e n 1490
Cape). Si e managemen plans o he emaining na ional pa ks a e being compiled, bu we e no 1491
a ailable o assessmen . The plans o six p o ec ed a eas in Gau eng P o ince co e ed 25 000 ha and 1492
a e included in Figu e 5.1 unde “o he go e nmen agencies”. Plans in his ca ego y co e ed 371 442 1493
ha. The e was a small con ibu ion (in e ms o a ea co e ed) om he p i a e sec o . 1494
In he i s s a us epo (SANBI and CIB 2018) planning co e age was es ima ed o be 2.4 million ha 1495
on he basis o plans submi ed. No all o hese plans we e ob ained in he subsequen epo , and so 1496
i is unclea whe he he plans ha e been upda ed o ha e lapsed. The a ea co e ed by cu en plans 1497
he e o e appea s o ha e dec eased, al hough his conclusion can only be based on plans ha we e 1498
submi ed; o he plans p obably exis bu we e no a ailable o assessmen . Howe e , he e appea s 1499
o ha e been a ma ked imp o emen in he adequacy o planning. In he i s epo , plans o 98% o 1500
he a ea co e ed we e assessed as inadequa e. The cu en es ima e is ha planning in almos hal 1501
(45.1%) o he a ea was adequa e, and jus o e hal (53.6%) was pa ially adequa e, wi h only 1.3% o 1502
he planning being sco ed as inadequa e. The adequacy o planning co e age, whe e i is done, hus 1503
appea s o ha e imp o ed subs an ially since he las s a us epo . 1504
1505
54
1506
Figu e 5.1 The a ea co e ed by cu en si e managemen plans submi ed o SANBI by di e en g oups 1507
wi hin go e nmen and he p i a e sec o . Da a summa ized he e a e o plans ha a e s ill cu en in 1508
e ms o he s a ed planning ho izon (plans ha did no include a planning ho izon we e assumed o 1509
be alid om he da e o submission o 5 yea s). Plans ha we e submi ed o p e ious s a us epo s, 1510
and ha a e s ill cu en , o ha e been upda ed, a e included. Shading indica es he adequacy o he 1511
plan. 1512

55
Table 5.4 Si e managemen plans submi ed by o ganisa ions o assessmen in e ms o hei adequacy. In cases whe e no plans we e submi ed o SANBI he 1513
a ea co e ed by he plans is conside ed o be 0. 1514
O ganisa ion
Si es o be managed
A ea co e ed
by plans (ha)
Adequacy o plans
No es
Depa men o
Fo es y, Fishe ies
and he En i onmen
Na u al Resou ce
Managemen
p og ammes
(Wo king o Wa e )
Wo king o Wa e has many p ojec s
ac oss all 9 p o inces
0
NA
No plans we e submi ed. Wo king o Wa e does no p epa e
managemen plans as his is he esponsibili y o indi idual
landowne s (p i a e and s a e) o who hey p o ide suppo .
Howe e , Wo king o Wa e has unded he de elopmen o six
demons a ion “managemen uni con ol plans” (MUCPs)1 o
he uppe ca chmen o he Be g Ri e ; Cape Na u e’s Wa e al
Cen e; he ca chmen s o he Holsloo , Keu booms and Ka a a a
i e s; and he G ea e Simonsbe g Conse ancy. They will be
assessed once hey a e ecei ed.
Cape Na u e
P o ec ed a eas in he Wes e n Cape
P o ince.
607 142
Adequa e (486 476 ha)
Pa ially adequa e (120 666
ha)
19 plans co e ing 31 p o ec ed a eas we e submi ed by Cape
Na u e; some plans co e mo e han one p o ec ed a ea
“complex”. In addi ion, demons a ion “managemen uni
con ol plans” (see abo e) ha e been p epa ed o he uppe
ca chmen o he Be g Ri e , and he Wa e al complex, bo h
managed by Cape Na u e.
Sou h A ican
Na ional Pa ks
Na ional Pa ks in Sou h A ica.
69 873
Pa ially adequa e (49458
ha)
Inadequa e (20415 ha)
Sou h A ican Na ional Pa ks epo ed ha de ailed plans o he
managemen o biological in asions in 17 ou o 22 na ional pa ks
had been comple ed, bu only h ee we e submi ed o
assessmen , and a e epo ed he e.
Gau eng p o incial
ese es
Six p o ec ed a eas wi hin he Gau eng
P o ince
25 000
Pa ially adequa e
Plans we e p epa ed o he Abe Bailey, Alice Glöckne ,
Leeuw on ein, Roodeplaa Dam, and Suike bos and Na u e
Rese es and he Ma ie ale Bi d Sunc ua y.
Municipali ies
Municipal managemen plans a y in
hei co e age. Some ocus on p o ec ed
a eas wi hin he municipal bounda ies,
and o he s on he en i e municipal a ea.
567 329
Adequa e (250 000 ha)
Pa ially adequa e (317 329
ha)
Plans we e submi ed by he Be g Ri e , Bi ou, Bu alo Ci y (Eas
London), Cape Town, Eku huleni (Johannesbu g), eThekwini
(Du ban), Knysna, uMdoni, and Wi zenbe g municipali ies.
1 The MUCP so wa e can be downloaded om a si e main ained by And ew Wannenbu gh (awannenbu gh@d e.go .za) o he Ope a ional Suppo and Planning Di ec o a e in
he Na u al Resou ce Managemen p og ammes o he Depa men o Fo es y, Fishe ies and he En i onmen
(h ps://si es.google.com/si e/w wplanning/moni o ingande alua ion).
56
O ganisa ion
Si es o be managed
A ea co e ed
by plans (ha)
Adequacy o plans
No es
O he Go e nmen
The plans submi ed by la ge
go e nmen agencies ( o example
Eskom and T ansne ) co e some, bu
no all, o he land on which hey
ope a e.
371 442
Adequa e (863 ha)
Pa ially adequa e (370 485
ha)
Inadequa e (94 ha)
Plans we e submi ed by he B eede-Gou i z Ca chmen
Managemen Agency, Denel, Eskom, T ansne , and he Malo i
D akensbe g T ans on ie Conse a ion and De elopmen
P og amme.
The G ea e Cape
Town Wa e Fund
Ca chmen s o he Be g and
Theewa e skloo dams, and A lan is
aqui e , Wes e n Cape P o ince
0
NA
Plans we e no ecei ed and so he adequacy o he sys em has
no ye been assessed. The GCTWF has de eloped a decision
suppo sys em which guides managemen decisions based on
ongoing moni o ing o p og ess owa ds goals.
P i a e landowne s
Six plans we e submi ed by p i a ely-
owned companies o indi iduals
19 856
Adequa e (4 ha)
Pa ially adequa e (19 852
ha)
A demons a ion managemen uni con ol plan was also been
de eloped in 2016 o he G ea e Simonsbe g Conse ancy nea
S ellenbosch, which includes 33 p i a e landowne s. The plan is
no longe cu en .
1515
57
5.4 Ou pu —pa hways ea ed 1516
39 o 44 pa hways a e managed o some ex en , and his has no changed ecen ly. Howe e , o mo e 1517
han hal o hese pa hways, managemen is pa ial as i is ocused on speci ic species ha pose a 1518
h ea o ag icul u e o human heal h, and o e looks o he h ea s (see supplemen a y ma e ial S5.12). 1519
Impo an pa hways ha a e s ill no managed include ballas wa e , and bio ouling on aqua ic essels. 1520
Sou h A ica is a signa o y o he In e na ional Ma i ime O ganisa ion (IMO), and mus gi e e ec o 1521
he In e na ional Con en ion o he Con ol and Managemen o Ships' Ballas Wa e and Sedimen s 1522
(BWM) h ough na ional legisla ion. Howe e , he e has been no p og ess on he d a Ballas Wa e 1523
Managemen Bill since 2017, when i was ou o public commen . The BWM will ha e a ela i ely low 1524
global inancial cos in compa ison o o he en i onmen al policies, and i he IMO s anda ds a e 1525
implemen ed uni o mly ac oss he wo ld, hen he es ima ed cos s o Sou h A ica a e low [expo s 1526
a e es ima ed o dec ease by 0.01% (USD 15M), and impo s by 0.03% (USD 31M)] (Wang e al. 2020). 1527
T ansne Na ional Po s Au ho i y had planned o implemen in-wa e hull cleaning, howe e , his 1528
ini ia i e appea s o ha e s alled (Jacka 2021). Resea ch has explo ed al e na i es, including 1529
encapsula ing yach s, whe e a s uc u e (e.g., hull) is w apped in plas ic o dep i e bio ouling 1530
o ganisms o oxygen and ood, and ul ima ely causing hei dea h, hough u he es ing is equi ed 1531
(Keanly and Robinson 2020) be o e widesp ead implemen a ion can be conside ed. 1532
The e has been li le change since he second epo o he ope a ions ca ied ou by DFFE a OR Tambo 1533
In e na ional Ai po , whe e o icials pe o m inspec ions a he mail cen e, he a i als, depa u es, 1534
and ca go e minals, and a he p i a e e minal, Fi eblade. A he ime o he second epo , 1535
inspec ions a Fi eblade had no ye commenced. Al hough inspec ions a e being pe o med a mo e 1536
loca ions a OR Tambo, hi ing and keeping o icials o pe o m hese inspec ions is a challenge, and he 1537
ime and esou ces equi ed o capaci a e new o icials is high. DFFE uns one join ope a ion wi h 1538
o he en i ies pe qua e , and while his assis s o alle ia e capaci y cons ain s, some o hese 1539
ope a ions we e cancelled in 2020/2021 o educe he isk o o icials con ac ing COVID-19. Be ween 1540
Janua y 2020 and Decembe 2022 DFFE pe o med ~ 98 000 inspec ions a OR Tambo In e na ional 1541
Ai po , wi h mos o hese being pe o med a he mail cen e (~ 17 000), and he a i als (~ 64 000) 1542
and depa u es (~17 000) e minals (Figu e S5.3). No inspec ions we e pe o med be ween Ma ch 1543
2020 and Oc obe 2020, due o COVID-19 (Figu e S5.3). Almos all he impo ed ca go consignmen s 1544
inspec ed (98% o ~ 260 consignmen s) we e o Psi acula k ame i ( ose- inged pa akee ), wi h one 1545
consignmen inspec ed o each o : Lissacha ina ulica (gian A ican snail), Mo elia spilo a (diamond 1546
py hon), O eoch omis nilo icus (Nile ilapia), and Hyd ochoe us hyd ochae is (capyba a). These axa 1547
a e all egula ed unde he NEM:BA A&IS Regula ions [see Appendix 2 and Wilson (2023) o de ails]. 1548
58
Inspec ions o impo ed plan s, animals, and hei p oduc s o ag icul u al h ea s a e pe o med by 1549
DALRRD a a ious po s o en y and o he si es (e.g., Na ional Plan and Plan P oduc Inspec ion 1550
Se ices egional o ices). I a suspec ed plan pa hogen o pes is ound du ing an inspec ion, es s a e 1551
pe o med o ‘qua an ine pes s’ by Plan Diagnos ic Se ices. Plan diagnos ic se ices also pe o ms 1552
hese es s on ‘audi samples’, and some impo ed animals and plan s a e also kep unde qua an ine 1553
while u he es s a e done. ‘Qua an ine pes s’ a e hose ha ha e been assessed h ough a pes isk 1554
analysis, ha e been deemed o pose an unaccep able isk o ag icul u e, and a e p ohibi ed om 1555
en e ing he coun y. O e he pe iod om 1 Ap il o 31 Decembe 2022, DALRRD pe o med ~14 000 1556
inspec ions o animal/animal p oduc impo s, ~67 000 inspec ions o plan s/plan p oduc impo s, 1557
and ~50 000 inspec ions o phy osani a y ce i ica es. The as majo i y o hese inspec ions (90% o 1558
he animal impo s, 85% o he plan impo s, and 100% o he phy osani a y ce i ica es) we e o 1559
impo s o comme cial pu poses. In addi ion, 286 plan and 966 animal impo s we e placed in 1560
qua an ine o u he es ing, and Plan Diagnos ic Se ices pe o med o e 9 000 es s on o e 4 000 1561
samples. In his epo in o ma ion on he a -bo de inspec ions, and ela ed ac i i ies, by DALRRD is 1562
epo ed o 2022 only, as DALRRD was unable o supply he in o ma ion o 2020 and 2021. 1563
The Bo de Managemen Au ho i y, which was es ablished h ough he Bo de Managemen Au ho i y 1564
Ac o 2020, and which will be ully ope a ional in 2023, is an impo an de elopmen in he 1565
managemen o pa hways. In p e ious epo s, i was highligh ed ha Sou h A ica’s uncoo dina ed 1566
app oach o bo de managemen was likely cos ly and ine ec i e, and ha species ha pose 1567
en i onmen al h ea s we e likely o be o e looked a po s o en y whe e inspec ions la gely ocus 1568
on ag icul u al pes s o animal and human diseases ( an Wilgen and Wilson 2018, Zengeya and Wilson 1569
2020). The BMA in ends o be he single au ho i y o he managemen o Sou h A ica’s bo de s, 1570
in eg a ing and co-o dina ing he unc ions cu en ly pe o med by a ious go e nmen depa men s 1571
a po s o en y, including hose pe o med by DFFE and DALRRD. This p omises o be an imp o emen 1572
on he cu en app oach which comp ises mul iple au ho i ies wi h di e en manda es. 1573
5.5 Ou pu —species ea ed 1574
Based on submissions ecei ed, 196 o he 559 egula ed axa ecei ed some managemen ea men 1575
du ing 2020–2022 (Table 5.5). In e ms o alien ag icul u al pes species, 39 a e con olled by 48 1576
es ablished biological con ol agen s, al hough only one o hese pes species [Pseudococcus 1577
calceola iae ( he sca le mealybug)] is lis ed unde he NEM:BA A&IS Regula ions. 1578
Du ing 2020–2022, 48 alien plan biological con ol agen s we e ac i ely managed o inc ease hei 1579
abundance o ex en (e.g., h ough mass ea ing, e- elease, o dis ibu ion o new a eas, see Table 1580
65
economically jus i iable, bu he cos o ully es o ing ecosys em s uc u e, unc ioning, and 1749
composi ion in highly deg aded ecosys ems has a ely been deemed economically jus i iable in Sou h 1750
A ica (Holmes e al. 2020; an Wilgen e al. 2022). Gene ally, go e nmen -suppo ed con ol 1751
ope a ions ha e no included es o a ion e o s, a leas in pa because he e is li le o no unding 1752
o implemen ing ac i e es o a ion p ojec s a he necessa y scale—mos si es a e le o passi e 1753
es o a ion ( an Wilgen e al. 2022). 1754
1755

66
Box 5.1 The egula ion o in asi e species used in comme cial imbe plan a ions 1756
One o he majo sou ces o plan in asions in Sou h A ica is he sp eading o in asi e ees om 1757
comme cial imbe plan a ions, which is ongoing despi e he o es y sec o being hea ily egula ed. 1758
Se e al ee species used in plan a ions in Sou h A ica ha e been lis ed as in asi e species unde he 1759
Na ional En i onmen al Managemen : Biodi e si y Ac , 2004 (Ac No. 10 o 2004)’s (NEM:BA) Alien 1760
and In asi e Species Regula ions o 2020 (A&IS Regula ions). In e ms o he A&IS Regula ions, a 1761
pe mi is equi ed o es ablish a new plan a ion o o ex end an exis ing plan a ion in ol ing hose 1762
species [see Appendix 6 o he pe mi s issued pe axon, and Wilson (2023) o de ails o he lis ed 1763
axa]. Impo an ly, he Minis e o Fo es y, Fishe ies and he En i onmen has, in e ms o NEM:BA, 1764
exemp ed exis ing plan a ions— hose plan a ions ha we e es ablished and ope a ional be o e 1 1765
Augus 2014, when he A&IS Regula ions i s came in o ope a ion— om he equi emen o ob ain 1766
a pe mi in e ms o NEM:BA and he A&IS Regula ions. 1767
One o he p e equisi es o a pe mi o a es ic ed ac i i y in ol ing an in asi e species is ha he 1768
applican mus ha e demons a ed ha adequa e measu es will be aken o p e en he sp ead o 1769
he ele an in asi e species. The A&IS Regula ions also p o ide o compulso y condi ions in hese 1770
pe mi s, including ha he holde o he pe mi mus be equi ed o ake all necessa y s eps o 1771
p e en he escape and sp ead o he species. 1772
NEM:BA pe mi s a e no he only egula o y ool ele an o plan a ions. Addi ional egula o y 1773
equi emen s o plan a ion o es y include: 1774
• A wa e use licence (WUL) in e ms o he Na ional Wa e Ac , 1998 (Ac No. 36 o 1998) 1775
(NWA) o any “s eam low educ ion ac i i ies,” which includes he use o land o 1776
comme cial a o es a ion; 1777
• En i onmen al au ho isa ion o a plan a ion exceeding 300 ha in ex en in e ms o he 1778
Na ional En i onmen al Managemen Ac , 1998 (Ac No. 107 o 1998) (NEMA); 1779
• A licence o es ablish o ecommission a plan a ion in a S a e Fo es in e ms o he Na ional 1780
Fo es s Ac , 1998 (Ac No. 84 o 1994) (NFA); and 1781
• Consen om he ele an au ho i ies o g ow speci ied in asi e plan species in a eas o he 1782
han hose iden i ied in WULs o o he speci ically dema ca ed a eas in e ms o he 1783
Conse a ion o Ag icul u al Resou ces Ac , 1983 (Ac No. 43 o 1983) (CARA). 1784
The addi ional egula o y app o als abo e may be subjec o app op ia e condi ions, bu unlike he 1785
pe mi s issued unde he A&IS Regula ions, hey do no equi e he ope a o s o p e en he sp ead 1786
o he in asi e species beyond he app o ed a ea. This may well become p oblema ic in he case o 1787
67
exis ing plan a ions ( hose es ablished be o e 1 Augus 2014) o which pe mi s issued unde he 1788
A&IS Regula ions a e no equi ed. 1789
While he e is a gene al du y o e adica e o con ol lis ed in asi e species in NEM:BA, ha 1790
esponsibili y only applies o owne s o land on which he in asi e species is p esen . Comme cial 1791
o es y companies ha ope a e exis ing comme cial plan a ions ( hose es ablished be o e 1 Augus 1792
2014) in S a e Fo es s (owned by he S a e) he e o e do no ha e ha gene al du y o ca e. In hose 1793
ins ances, he S a e bea s he du y o ca e. 1794
E iden ia y p oo ha in asi e plan s ha e sp ead om a pa icula p ope y is o en also di icul o 1795
ob ain, especially whe e he e a e mul iple plan a ions in an a ea. 1796
Thus, despi e he mul i ude o legisla ion ha applies o comme cial o es y in Sou h A ica, o es y 1797
ope a o s managing plan a ions es ablished be o e 1 Augus 2014 in S a e Fo es s do no ha e he 1798
esponsibili y o p e en he sp ead o he in asi e ees o neighbou ing p ope ies and beyond. In 1799
hose ins ances, he S a e bea s ha esponsibili y. In cases whe e comme cial ope a o s a e 1800
equi ed in e ms o pe mi s issued unde he A&IS Regula ions o p e en he sp ead o in asi e 1801
species o neighbou ing p ope ies and beyond, i is also di icul o en o ce gi en he di icul y in 1802
ob aining e iden ia y p oo o he o igin o in asi e specimens. Thus, a subs an ial a ea o 1803
comme cial o es y emains as an un egula ed seed sou ce o e-in ading adjacen a eas ha ha e 1804
been clea ed. 1805
1806
Box Figu e 5.1. Fo es y plan a ions (backg ound) a e a majo and ongoing sou ce o p opagules o 1807
in ading adjacen a eas ( o eg ound). Pho o: B ian an Wilgen. 1808
1809
68
Box 5.2 The G ea e Cape Town Wa e Fund 1810
Conce n abou he g owing impac o in asi e ees on Cape Town’s wa e supplies led o he 1811
es ablishmen o he G ea e Cape Town Wa e Fund in 2018. The und was based on a easibili y 1812
s udy (Tu pie e al. 2017) and business case (S a o d e al. 2018) which showed ha clea ing Cape 1813
Town’s p io i y wa e ca chmen s by emo ing in asi e ees could gene a e annual wa e gains o 1814
50 billion li es wi hin i e yea s—equi alen o one-six h o he ci y’s cu en supply needs. These 1815
gains could double o 100 billion li es annually wi hin 30 yea s. This app oach was es ima ed o be 1816
signi ican ly mo e cos -e ec i e han o he wa e augmen a ion solu ions. 1817
The und is co-o dina ed by he Na u e Conse ancy (a US-based NGO), and is a pa ne ship be ween 1818
na ional, p o incial, and local go e nmen depa men s, co po a e sponso s (including Nedbank, 1819
Coca-Cola, AB-InBe , and REMGRO), and NGOs ( he Na u e Conse ancy and he Sou h A ican 1820
b anch o he Wo ld Wide Fund o Na u e). 1821
1822
Box Figu e 5.2 Wo ke s om he G ea e Cape Town Wa e Fund emo ing in asi e pine ees om 1823
he ca chmen o he Theewa e skloo dam ( isible in he igh -hand backg ound). Pho o: Louise 1824
S a o d. 1825
The und has a ge ed he ca chmen s o Cape Town’s majo supply dams a Theewa e skloo , 1826
Be g i e , Wemme shoek, and S eenb as, as well as he echa ge basin o he A lan is aqui e (Box 1827
Figu e 5.1). The und has a blended unding model and a 30-yea ime ho izon. I has aised ZAR 182 1828
million o he equi ed ZAR 372 million in unding o i s i s six yea s o ope a ion, wi h signi ican 1829
con ibu ions om co po a e sponso s (28% o unds aised o da e), philan h opic indi iduals and 1830
ounda ions (46%), and he Ci y o Cape Town (26%). 1831
69
The und’s key objec i e is o educe he co e o ma u e alien ees o below 5% wi hin 30 yea s, 1832
and es o e a co e o na u al ege a ion whe e possible. The und has al eady spen ~ZAR 100 1833
million, and is now hal way o achie ing i s ini ial 6-yea a ge o clea ing 55 300 ha. Abou 75% o 1834
he clea ed a ea was uppe ca chmen s in aded by alien pine (genus Pinus) ees. The und uses a 1835
cus om-buil decision suppo sys em o guide i s ope a ions. The sys em acks all clea ing and 1836
ollow-up ope a ions, and p io i ises si es o in e en ions. In e en ions a e also egula ly 1837
moni o ed o assess he e ec i eness o ope a ions, as well as ecosys em eco e y and social 1838
bene i s gene a ed. 1839
The implemen a ion o his und, which a ge s ca e ully p io i ised a eas, and includes he necessa y 1840
componen s o planning and moni o ing p o ides an excep ional example o he implemen a ion o 1841
bes p ac ice in he con ol o plan in asions wi h clea goals and ime ames. I is also unique in ha 1842
i ob ains unding om mul iple sou ces, and p o ides a model o he planning o simila 1843
in e en ions elsewhe e. 1844
1845
70
Box 5.3 Success ul biological con ol o wa e hyacin h on a eu ophic sub- opical wa e -body 1846
Pon ede ia c assipes (wa e hyacin h) has caused Majo impac s wo ld-wide by co e ing wa e 1847
bodies in ege a ion, educing oxygen le els in he wa e , and he eby al e ing he di e si y o 1848
eshwa e ben hic communi ies and impac ing he p o ision o ecosys em se ices (including 1849
oppo uni ies o ishing, and ec ea ional oppo uni ies such as swimming and boa ing). Biological 1850
con ol has been highly success ul in opical a eas, bu in mo e sub- opical, eu ophic wa e s 1851
biological con ol has been less success ul, especially whe e coole win e clima es p e ail. 1852
In Sou h A ica au ho i ies ha e eso ed, a conside able expense, o sp aying he bicides om 1853
ai c a and boa s. Howe e , plan s a e able o e-colonise hese sp ayed a eas apidly, empo a ily 1854
escaping biological con ol. This means ha sp aying ope a ions need o be cons an ly epea ed, 1855
adding ano he sou ce o chemical pollu ion o he wa e s. 1856
A ela i ely new addi ion o he sui e o biological con ol agen s was Megamelus scu ella is, which 1857
was i s eleased in Sou h A ica in 2013. This insec was p omising because i esponds well o mass 1858
ea ing, ep oduces apidly, and eco e s quickly a e pe iods o coole empe a u es. In addi ion, i 1859
can be excep ionally damaging o wa e hyacin h. Insec s we e mass- ea ed, and eleased in a s and-1860
alone in e en ion on Ha beespoo Dam in 2018 in he absence o he bicide ea men s. 1861
Following equen inunda i e eleases o he agen s, Coe zee e al. (2022) epo ed ha wa e 1862
hyacin h co e was educed om o e 37% o less han 6% o e wo consecu i e yea s (Box Figu e 1863
5.2). The ecommenda ion was o elease he insec s o en and in high numbe s o inunda e and 1864
o e whelm he wa e hyacin h and o achie e con ol a a ac ion o he cos o he bicide 1865
applica ions. This ep esen s a majo b eak h ough in he con ol o wa e hyacin h in Sou h A ica 1866
(and po en ially in o he sub- opical and empe a e eu ophic wa e bodies wo ldwide). 1867
1868
Box Figu e 5.3 Declines in he co e o wa e hyacin h be ween A) Janua y 2017 and B) Feb ua y 2020 1869
due o biocon ol by Megamelus scu ella is. Wa e hyacin h is he b igh g een agains he black wa e 1870
in he sa elli e images. This con ol happened in he absence o he bicide applica ions. Figu e om 1871
Coe zee e al. (2022) 1872
1873

71
5.10 T ends in in e en ions indica o s 1874
Indica o T end Con idence
Desi ed
end
1
Cu en s a us and end Ou look
12. Quali y o
egula o y
amewo k
→ Medium ↗
The amendmen s o NEM:BA and he A&IS Regula ions
and Lis s ha e imp o ed he egula o y egime sligh ly.
The law e o m has cla i ied some concep s and one o
he changes may well help he Depa men o p io i ise
whe e o ocus sca ce law en o cemen in e en ions.
Howe e , he undamen al p oblems iden i ied in he
p e ious epo ha e no been add essed, including he
absence o a comp ehensi e s a egy o guide
implemen a ion o he egula ions and lack o lexibili y in
he egula o y egime.
A d a na ional s a egy on biological in asions has been
de eloped bu no , as ye , se o public commen .
The ecen publica ion o he Whi e Pape on he
‘Conse a ion and Sus ainable Use o Sou h A ica’s
Biodi e si y’ is an indica ion ha DFFE plans o amend
NEM:BA in he nea u u e. Howe e , he Whi e Pape
does no add ess he p oblems wi h he cu en
egula o y egime, and does no comp ehensi ely add ess
issues a ound biological in asions.
The de elopmen and implemen a ion o a na ional
s a egy o biological in asions has he po en ial o be a
miles one in he managemen o biological in asions in
Sou h A ica.
The de elopmen and implemen a ion o a p ocess o
egula ly and anspa en ly upda e he egula o y lis s
in o med by he bes a ailable scien i ic e idence is
p omising.
13. Money
spen
↘
Low ↗2
An es ima ed R1.4 billion was spen be ween 2020 and
2022. This is an unde es ima e as no all go e nmen
en i ies, NGOs o he p i a e sec o ha e p o ided
es ima es. Howe e he amoun spen has been declining
in eal e ms since 2015 ( an Wilgen e al. 2022).
Go e nmen ’s abili y o und he con ol o biological
in asions has been educed due o ad e se economic
condi ions ha ha e p e ailed o e he pas ew yea s.
La ge inc eases in unding a e unlikely in he nea u u e.
The G ea e Cape Town Wa e Fund may p o ide a new
model o such und aising (Box 5.2).
1→ no change; ↗ an inc ease; ↘ a dec ease
2 Technically he desi ed alue o money spen would be ha es ima ed o be equi ed (e.g., so ha e u ns on in es men o addi ional spending on a e age end up as
ze o). Howe e , es ima es o he money equi ed o b ing biological in asions unde e ec i e con ol sugges his igu e is oughly 4.6 imes g ea e han cu en budge s
( an Wilgen e al. 2016). A p esen , i spen s a egically, he e a e signi ican e u ns on in es men o be had by spending money on con olling in asions, and he e o e
he desi ed end is o he e o be an inc ease in he money spen .
72
Indica o T end Con idence
Desi ed
end
1
Cu en s a us and end Ou look
14. Planning
co e age
→ Medium ↗
Pa hways: 40 o he 44 pa hways a e assumed o ha e
managemen plans in place, bu hese ha e no
necessa ily been o malised. No o mal plans ha e been
de eloped by DFFE, and he e is no legal equi emen o
do so. The e has been no change since he p e ious
epo .
Species: 23 (16 lis ed and 7 unlis ed) species ha e
managemen plans in place. 13 we e sco ed as adequa e,
8 as pa ially adequa e and 2 as inadequa e. This is 2.8%
o he 566 in asi e species lis ed in he egula ions. None
o hese plans ha e been o mally adop ed, no is he
p ocess o o mal adop ion clea , al hough landowne s
a e equi ed by law o con ol species on hei land in
acco dance wi h such plans, should hey exis [NEM:BA
Sec ions 75(4) and 75(5)].
Si es: Cu en managemen plans co e 1.6 million ha a e
(8.2% o he es ima ed in aded a ea). Planning co e age
appea s o ha e declined al hough mo e plans p obably
exis bu we e no submi ed o assessmen . Si e plans
ha we e submi ed we e assessed as imp o emen s
o e p e ious plans.
The e is s ill a need o iden i y p io i y pa hways, and
de elop and o mally adop plans o suppo he
managemen o hose pa hways.
The e is a simila lack o o mal planning p ocesses o
add ess species and si es. Wi hou such planning i will
no be possible o managemen o be s a egic and
di icul o managemen o be adap i e.
15. Pa hways
ea ed → Low ↗
All pa hways h ough which alien o ganisms can be
in oduced equi e managemen , and cu en ly 39 o he
44 pa hways (89%) a e managed o some ex en . Mos o
he pa hways ha a e managed a e pa ially managed
(51%), bu many (49%) ha e comple e managemen .
The e has been no change since he second epo .
The es ablishmen o he Bo de Managemen Au ho i y
could esul in mo e co-o dina ed managemen o
pa hways. The implemen a ion o ballas wa e
managemen bill would also imp o e he si ua ion.
Howe e , he e is s ill a need o iden i y p io i y
pa hways, and de elop pa hway- ocused managemen
o hose pa hways.
73
Indica o T end Con idence
Desi ed
end
1
Cu en s a us and end Ou look
16. Species
ea ed → Low ↗
196 ou o 559 egula ed axa (~35%) ha e been
subjec ed o some o m o managemen . Mos e o is
di ec ed owa ds widesp ead o damaging species o
owa ds species ha a e po en ial e adica ion a ge s.
Se e al in asi e species a e expanding hei anges
apidly, so capaci y o deal wi h all species will be u he
educed.
The na ional s a egy on biological in asions, in conce
wi h he GBF (Box 1.2) is likely o incen i ise g ea e
p io i isa ion o con ol e o s agains he mos damaging
lis ed in asi e species, and hose ha p esen he
g ea es u u e h ea s
17. Si es
ea ed No assessed ↗
The a ea ha has been ea ed 2020–2022 is es ima ed o
be 2003 km2, his includes all land pa cels ha ha e been
wo ked on by public wo ks alien plan con ol eams. The
es ima ed o al in aded a ea in Sou h A ica is 194 943
km2, so con ol ope a ions ha e he e o e eached jus
o e 1% o he es ima ed in aded a ea. A ecen s udy
es ima ed ha con ol ope a ions be ween 1998 and
2020 had eached 14% o he es ima ed a ea o e 22
yea s ( an Wilgen e al. 2022). Because con ol ope a ions
a e no ollowed up e e y yea , i may be necessa y o
examine he ex en o ea men o e longe pe iods.
The e a e subs an ial unce ain ies ega ding he
es ima ed ex en o in asion. Con ol also o en does no
co e he ull a ea mapped as ha ing ecei ed con ol, so
he 1% (and he 14%) a e p obably o e es ima es.
I is expec ed ha he a ea in aded in Sou h A ica will
inc ease. P ocesses a e, howe e , in place o ensu e
g ea e p io i isa ion o con ol e o s o ensu e p io i y
si es a e clea ed and kep clea (c . ou look o 16. Species
ea ed).
18.
E ec i eness
o pa hway
ea men s
→ Low ↗
The e has been no change o he es ima ed e ec i eness
o pa hway managemen o mos pa hways. Fo one
pa hway, eleases o conse a ion, he e ec i eness o
managemen could be es ima ed o he i s ime, and
was es ima ed o be pa ially e ec i e. Fi e pa hways a e
no managed, 17 ha e ine ec i e managemen , one has
pa ially e ec i e managemen , six ha e e ec i e
managemen , and one has pe manen managemen .
The es ablishmen o he Bo de Managemen Au ho i y,
and h ough ha he co-o dina ion o he a -bo de
managemen o pa hways will hope ully imp o e he
e icacy o a -bo de managemen . Howe e , he e is s ill
a need o measu e he e icacy o managemen using
good da a, and adap whe e equi ed.
74
Indica o T end Con idence
Desi ed
end
1
Cu en s a us and end Ou look
19.
E ec i eness
o species
ea men s
→ Low ↗
Fo mos o he 566 egula ed axa, he e is no e idence
ha any managemen is aking place, and wi h he
excep ion o species unde biological con ol, he
e ec i eness o managemen is no known. Upda ed
es ima es will be included in he inal epo .
Assessing he e ec i eness o species ea men s a a
na ional scale is based on changes in he size o he
popula ion ( o animals) o he ex en o in asion ( o
plan s). These a e cu en ly no moni o ed excep o
some alien plan s ha a e he a ge o biological con ol.
The absence o a eliable baseline and egula upda es
will con inue o p e en accu a e assessmen s o con ol
e ec i eness, especially a a na ional scale. When
assessed a ine scales, he e a e examples o pa ially
e ec i e ea men s o species a some si es.
20.
E ec i eness
o si e
ea men s
No assessed
The pauci y o managemen plans wi h clea goals and
egula moni o ing o hose plans makes i di icul o
assess e ec i eness, which would ha e o be exp essed in
e ms o p og ess owa ds achie ing he goal. Fo some
a eas whe e in o ma ion is a ailable, he e a e indica ions
ha some in e en ions a e a leas pa ially e ec i e,
bu he goals o managemen a e ypically uns a ed,
making such assessmen s di icul . The e is no
in o ma ion o sugges ha he si ua ion has changed
since he second epo .
The e a e almos no ou inely-collec ed da a o assess he
e ec i eness o si e ea men s, ei he in e ms o
changes in he ex en o he a ea in aded, o in e ms o
ecosys em eco e y ollowing con ol. Accu a e
assessmen s a e only possible o small a eas ha ha e
been he subjec o esea ch s udies.
High-le el
indica o
D. Le el o
success in
managing
in asions
No assessed
This indic o canno be calcula ed as he e a e e y ew
da a on he e ec i eness o con ol o in asions a
speci ic si es.
Making a easonably accu a e assessmen o he o e all
success o managing in asions emains challenging due o
he pauci y o s a ed goals in managemen plans agains
which o assess p og ess, as well as he sca ci y o
ac i i ies o egula ly moni o p og ess owa ds goals. As
epo ed in he second epo , hese issues need o be
u gen ly add essed, because wi hou hem e ec i eness
canno be known, managemen canno be adap i e, and
he impac s and cos s o in asions will con inue o ise.
The p oposed na ional s a egy and ac ion plan on
biological in asions may help explici ly add ess hese
issues.
1875
81
ha he unaided pa hway is impo an o alien plan s on he islands; we suspec ha his is a common 2026
pa hway o dispe sal o alien species. On Ma ion Island, i is hough ha Sagina p ocumbens was 2027
sp ead om he esea ch base by helicop e du ing annual es ocking o he hu s (G emmen and Smi h 2028
1999). The cons uc ion o a s eel helicop e pad a he new esea ch base has likely educed dispe sal 2029
h ough his pa hway, al hough he helicop e s ill lands on ege a ion a he hu s and so migh s ill 2030
be esponsible o sp eading p opagules. I is likely ha some p opagules a e sp ead by ield wo ke s, 2031
bu his has no been in es iga ed. 2032
Table 6.2. The wi hin-coun y pa hways by which alien species a e known, o s ongly suspec ed, o 2033
sp ead on he P ince Edwa d Islands. Pa hways no depic ed a e no p esen , highligh ing he low 2034
numbe o possible pa hways a ailable wi hin he islands. 2035
Pa hway ca ego y
& subca ego y
Wi hin-coun y
pa hway
p ominence
Examples o wi hin-coun y dispe sal
T anspo -
s owaway:
People/equipmen
No known
I is assumed ha his is an impo an pa hway on Ma ion Island, bu i
has no been speci ically moni o ed excep o Lee and Chown (2011)
who ound 420 seeds ca ied on 225 di e en clo hes i ems on
expedi ione s ha we e e u ning o mainland om Ma ion Island, and
could ha e po en ially sp ead hose p opagules wi hin he island (a
leas h ee seed we e o highly in asi e plan species).
T anspo -
s owaway:
Con aine and bulk
ca go
Mino
Sagina p ocumbens was possibly sp ead ac oss he island du ing hu
es ocking, when con aine s a e d opped a hu s by helicop e . This
happens once a yea . O he plan s could ha e been sp ead by his
means oo. The in asi e slug De oce as pano mi anum has been
sp ead a ound Ma ion Island h ough wooden c a es ha a e packed
a ound he esea ch s a ion p io o ai c a and ship ope a ions
(Chown e al. 2002).
Unaided
Mode a e
Se e al plan species ha e sp ead o e ai ly la ge dis ances on P ince
Edwa d Island du ing a ime when no humans isi ed he island. I can
be expec ed ha mos inc eases in he ange o in asi e species on
Ma ion Island a e simila ly unaided.
2036
6.2 Species 2037
6.2.1. Numbe and s a us o alien species 2038
Se en y- i e alien axa ha e been eco ded a some poin on he PEIs, wo axa a e eco ded as 2039
c yp ogenic (i.e., na i i y has no been con i med)1, and one plan , Oche ophila ine is, is hough o 2040
ha e a i ed unaided ia ag an bi ds om Sou h Ame ica since humans i s a i ed on he island 2041
(Kalwij e al. 2019), as so is conside ed na i e (Appendix 7). Ou o he 75 alien axa e e eco ded, 43 2042
1an uniden i ied mi e species om he amily Cillibidae was i s eco ded om Ma ion Island du ing 1996 o
1997 (Ma shall e al. 1999). This amily had no p e iously been eco ded in he sub-An a c ic and his species
was conside ed “likely” an in oduced species (Ma shall e al. 1999). Howe e , since his ini ial collec ion no
p og ess has been made in de e mining he iden i y o s a us o he species, despi e i equen ly being he
nume ically dominan mi e species in some habi a s (see e.g., Ba endse e al. 2002).

82
a e s ill p esen , he p esence o i e axa is doub ul un il e adica ion is con i med, and he emaining 2043
27 a e no longe p esen . The e a e cu en ly no alien axa in cap i i y no unde cul i a ion. O he 2044
43 alien axa cu en ly p esen , 24 a e in asi e, 11 a e na u alised bu no in asi e, wo a e p esen 2045
bu no na u alised, and six canno be assigned o one o he basic in oduc ion s a us ca ego ies (i.e., 2046
i is unclea i hey a e na u alised, in asi e, o nei he ) (Figu e 6.3). The e o e, mo e han hal o he 2047
alien axa p esen on he PEIs a e in asi e. O he 24 in asi e axa, 17 a e in e eb a es, i e a e plan s, 2048
one is a ungus, and one is a mammal; he e a e no alien bi ds, ep iles o amphibians (see Sec ion 2049
S6.2). All alien axa a e ei he e es ial o eshwa e species, as, despi e an ac i e sea ch, no ma ine 2050
alien species ha e been de ec ed o da e (G e e e al. 2020). 2051
2052
Figu e 6.3 The s a us o alien axa in oduced o he P ince Edwa d Islands (PEIs) as pe he Uni ied 2053
F amewo k (Blackbu n e al. 2011), including species ha we e p esen bu a e no longe (A1), see 2054
supplemen a y ma e ial S6.2 o a b eak-down in o unc ional g oups. The in oduc ion s a us o six 2055
axa is no known and hese a e no shown on his igu e. 2056
6.2.2. Ex en o alien species 2057
Dis ibu ion da a we e a ailable o all bu one alien axon on he PEIs. Fo Bake dania sp. (Aca i), i is 2058
unclea i he axon is p esen on P ince Edwa d Island. 2059
Es ima es om a 2008 s udy sugges ed ha less han 5% o he PEIs had been co e ed by alien plan s 2060
(G emmen and Smi h 2008). In a mo e ecen s udy, le Roux e al. (2013) de e mined ha alien plan 2061
species we e p esen in 42% o Ma ion Island’s hal minu e g id cells (hmgcs a e ~0.59 km2, oughly 2062
926 m by 635 m), and in 53% o P ince Edwa d Island’s hmgcs. Sagina p ocumbens (166 hmgcs), Poa 2063
annua (204 hmgcs) and Ce as ium on anum (162 hmgcs) a e he mos widesp ead species on bo h 2064
islands (DFFE 2010, le Roux e al. 2013, Mai al e al. 2022). Sagina p ocumbens and C. on anum 2065
oge he wi h in asi e sp ing ails (Ce a ophysella den icula a, Megalo ho ax minimus and 2066
83
Pogonogna hellus la escens) ha e inc eased hei dis ibu ion along he coole egions due o ising 2067
empe a u es associa ed wi h clima e change (Kgopong 2019). Fo occupancy de ails o each species, 2068
see Appendix 7. 2069
The ECOs a Ma ion Island ha e s a ed o map he ex en o in asions, and o c ea e polygon maps 2070
o assess p og ess on plan con ol measu es. DFFE p o ided da a o h ee species, Ag os is gigan ea 2071
(1.39 ha), Rumex ace osella (0.1 ha) and Luzula mul i lo a (1.2 ha) (see maps in supplemen a y 2072
ma e ial S6.3). 2073
6.2.3. Abundance o alien species 2074
G e e and le Roux ha e unpublished da a om ansec s comp ised by quad a s sampled a 2075
in e als, whe e hey assessed plan co e : na i e plan s had he highes pe cen age co e (54.6%), 2076
ollowed by ba e g ound/ ocks (42.8%) and las ly alien plan co e (2.6%). F om he alien plan 2077
co e , Sagina p ocumbens had he highes abundance (0.9%), ollowed by Poa annua (0.39%), 2078
Ag os is s oloni e a (0.1%), Ce as ium on anum (0.07%) and Poa p a ensis (0.04%). These alues, 2079
howe e , could be cu en ly lowe due o ongoing managemen ac ions. 2080
The abundance o alien (and c yp ogenic) in e eb a es has been assessed o di e en axonomic 2081
g oups [e.g., sp ing ails (Collembola), mi es (Aca i)], and he da a is p esen ed as indi iduals pe 2082
squa e me e in di e en ege a ion ypes o habi a s (Ba endse e al. 2002, Hugo e al. 2006, 2083
T easu e e al. 2019, Chown e al. 2022). In some s udies, mo e de ail is p o ided (e.g., li e s age, 2084
sex; Khoza e al. 2005), bu he e ha e been no es ima es o ‘exac o e all numbe ’ on any o he 2085
PEIs. Fo bo h islands, he alien (and c yp ogenic) abundance o in e eb a es a ied s ongly 2086
be ween habi a ypes and, o Ma ion Island, along he al i udinal g adien (Figu e 6.4, 2087
supplemen a y ma e ial S6.4). Fo Ma ion Island, alien sp ing ails we e mo e abundan on he mi e 2088
cha ac e ised by Sanionia uncina a (40 380 indi iduals/m2), and mi es we e mo e abundan in he 2089
sal -sp ay ege a ion o med by he na i e Co ula plumosa (2 623 indi iduals/m2) (Figu e 6.4). 2090
Simila ly, on P ince Edwa d Island he sal -sp ay ege a ion ype o C. plumosa was he mos 2091
common habi a o mi es (15 039 indi iduals/m2), al hough o sp ing ails he highes abundance 2092
was ound on slopes co e ed by he na i e Blechnum penna-ma ina (234 indi iduals/m2). 2093
The highes densi y o mice on he island was 231.8 mice/ha be ween 2008–2011, wi h a o al 2094
numbe o indi iduals es ima ed a 1 760 740 (McLelland e al. 2018). Mice densi y inc eased by 2095
430.0% be ween 1979–1980 and 2008–2011 (McLelland e al. 2018). 2096
84
2097
2098
Figu e 6.4. Abundance o a) alien sp ing ails on P ince Edwa d Island, b) alien sp ing ails on Ma ion 2099
Island, c) c yp ogenic mi es on P ince Edwa d Island, and d) c yp ogenic mi es on Ma ion Island, in 2100
e ms o indi iduals pe squa e me e. Labels on he x-axis indica e ege a ion ype and, whe e 2101
app op ia e, he plan species o he al i ude sampled wi hin he ege a ion ype. No e ha he y-axis 2102
limi s di e be ween panels. Bio ic: Poa = Bio ic g assland and he b ield (Poa cookii); Azo ella = 2103
Azo ella selago; Sal -sp ay = Coas al sal -sp ay; Co ula = Co ula plumosa; C assula = C assula 2104
moscha a; Acaena = Acaena magellanica; Blechnum = Blechnum penna-ma ina; Blepha = 2105
Blepha idophyllum densi olium; high-al = high-al i ude; James = Jamesoniella colo a a; mid-al = mid-2106
al i ude; Sanionia = Sanionia uncina a. 2107
6.2.4. Impac o alien species 2108
O he 20 axa assessed wi h da a om he PEIs using he EICAT scheme, one had a Massi e impac 2109
(house mouse) and ou had Majo impac s (Table 6.3, see Supplemen a y Ma e ial S6.2 o he 2110
app oach aken). The impac s o indi idual in asi e axa ha e been quan i ied in a numbe o cases 2111
o Ma ion Island: e.g., o he now e adica ed Felis ca us ( an Rensbu g and Bes e 1988; Hun e 2112
1990), o Mus musculus (C a o d 1990; Jones e al. 2019), and o he g ass Ag os is s oloni e a 2113
(G emmen 1997, G emmen e al. 1998). E en hough no EICAT assessmen s ha e been o mally 2114
unde aken and e iewed o he PEIs, se en species ( ou cu en ly p esen ) possess a global 2115
85
published EICAT assessmen ( h ee plan species ha e a Mode a e impac and he house mouse a 2116
Massi e impac ). 2117
Table 6.3 The numbe o alien axa wi h di e en le els o eco ded en i onmen al impac on he 2118
P ince Edwa d Islands (PEIs). Taxa we e assigned o a ious ca ego ies o impac based only on s udies 2119
om he PEIs (G e e e al. 2017), and no based on global EICAT assessmen s. 2120
Taxon
En i onmen al Impac (~EICAT)
Da a De icien
Minimal
Mino
Mode a e
Majo
Massi e
Mammals
0
0
0
0
0
1
Mic obial species
0
0
0
1
0
0
Te es ial and
eshwa e plan s
1 3 2 2 4 0
Te es ial
in e eb a es
22 0 5 1 0 0
2121
The g ea es eco ded impac s we e associa ed wi h he house mouse. The house mouse is o una ely 2122
only p esen on Ma ion Island, bu i has had impac s a he ecosys em- (C a o d 1990) and species-2123
le els, a ec ing he island’s only sho ebi d (Huyse e al. 2000), seabi ds (Jones e al. 2019, Jones and 2124
Ryan 2010, Dilley e al. 2017), na i e ege a ion (Phi i e al. 2009), and in e eb a es ( an Aa de e al. 2125
2004). The house mouse has had nega i e impac s on plan species su i al (Azo ella selago; Phi i e 2126
al. 2009) and ep oduc ion (Uncinia compac a; Chown and Smi h 1993), in e eb a e abundance, 2127
biomass and body size (Chown and Smi h 1993; C a o d and Schol z 1987; T easu e and Chown 2014; 2128
McClelland e al. 2018), and alba oss chick su i al (Jones and Ryan 2010, Dilley e al. 2017). House 2129
mouse bu owing also al e s sedimen mo emen a es (E iksson and Eld idge 2014), and likely 2130
impac s on nu ien cycling (C a o d 1990; Smi h and S eenkamp 1990). E idence shows ha he e 2131
has been a shi in mouse beha iou wi h p eda ion on seabi ds’ chicks inc easing o e ime, and 2132
ecen eco ds o mice a acking adul seabi ds (Jones e al. 2019). A guably such a beha iou al shi 2133
means he impac o mice has ecen ly inc eased ma kedly, emphasising he impo ance o achie ing 2134
e adica ion soon. 2135
Va ious plan s, including he g ass Ag os is s oloni e a, ha e had Majo impac s on na i e ege a ion 2136
and soil auna communi ies (G emmen 1997, G emmen e al. 1998). Ve y li le has been documen ed 2137
on he impac s o e es ial in e eb a es. Las ly, he ungal ascomyce e Bo yo inia uckeliana was 2138
ound o signi ican ly a ec he dis ibu ion and abundance o a na i e plan species (Kloppe s and 2139
Smi h 1998). 2140
6.3 Si es 2141
6.3.1. Alien species ichness 2142
86
Alien plan species ichness is highes close o he Ma ion Island base and me eo ological s a ion, and 2143
high along he no he n and eas e n coas al a eas, pa icula ly in a eas wi h cu en o his o ic 2144
an h opogenic dis u bances (e.g., esea ch ield hu s; le Roux e al. 2013). The highes alien plan 2145
ichness a he hmgc-scale was eigh species (a he esea ch s a ion). Alien plan ichness on P ince 2146
Edwa d Island is mo e e enly sp ead ac oss he island, wi h he highes ichness along he coas and 2147
he s eep esca pmen on he no h-wes e n side o he island [maximum alien plan species ichness 2148
a he hmgc-scale was h ee species; le Roux e al. (2013)]. 2149
6.3.2. Rela i e in asi e abundance 2150
The mean co e o all in asi e plan species is 2.6% on Ma ion Island (G e e unpublished da a). This 2151
es ima e is based on 501 plo s o 3 x 3 m ha a e sp ead ac oss he island. Gi en ha hese plo s co e 2152
only a small pe cen age o he island, con idence in his es ima e is low. The e is spa ial a ia ion in 2153
he ela i e in asi e abundance ac oss Ma ion Island. Coas al habi a s a e gene ally mo e in aded 2154
han inland habi a s. The e is no da a a ailable on he ela i e abundance o alien plan s o P ince 2155
Edwa d Island. 2156
Fo bo h islands, he ela i e in asi e abundance o in e eb a es a ied s ongly be ween habi a 2157
ypes and, o Ma ion Island, along he al i udinal g adien (Figu e 6.5). Sp ing ails a e ela i ely well 2158
su eyed, and ha e a ela i e in asi e abundance ha a ies be ween 0 and 2% on P ince Edwa d 2159
Island and be ween 0 and 90% on Ma ion Island (mean ela i e abundance = 28%; T easu e e al. 2019, 2160
Chown e al. 2022). The ela i e in asi e abundance o sp ing ails is highes a lowe al i udes, and in 2161
b yophy e- and e n-domina ed ege a ion ypes. Spide s ha e only been adequa ely sampled on 2162
Ma ion Island (and only om i e loca ions on he eas e n side o he island) o documen ela i e 2163
in asi e abundance, and da a shows ela i e in asi e abundance a ying om 0–98% (mean = 37%; 2164
Khoza e al. 2005). The ela i e abundance o alien spide s was lowes a he wo si es wi h he highes 2165
ele a ion on he island. Alien mi es comp ise 0–26% o all mi es on P ince Edwa d Island (mean = 8%; 2166
Hugo e al. 2006) and 3–28 % o mi es on Ma ion Island (mean = 14%; Ba endse e al. 2002). Howe e , 2167
due o unce ain y ega ding he iden i y (and s a us) o Cillibidae sp. no ., which comp ises c. 95–2168
100% o he alien mi e indi iduals sampled om he islands, he e is conside able unce ain y in hese 2169
es ima es. Rela i e in asi e abundance o Isopoda is 100% due o he absence o na i e isopods. 2170
Rela i e abundance da a o some axa (e.g., Insec a) a e no a ailable due o he lack o comple e 2171
su eys (i.e. no all species wi hin he axon eco ded du ing sampling). 2172

87
2173
2174
Figu e 6.5. Rela i e abundance o alien a) sp ing ails on P ince Edwa d Island, b) sp ing ails on Ma ion 2175
Island, c) mi es on P ince Edwa d Island, and d) mi es on Ma ion Island. Labels on he x-axis indica e 2176
ege a ion ype and, whe e app op ia e, he plan species o he al i ude sampled wi hin he 2177
ege a ion ype. No e ha he y-axis limi s di e be ween panels. Bio ic: Poa = Bio ic g assland and 2178
he b ield (Poa cookii); Azo ella = Azo ella selago; Sal -sp ay = Coas al sal -sp ay; Co ula = Co ula 2179
plumosa; C assula = C assula moscha a; Acaena = Acaena magellanica; Blechnum = Blechnum penna-2180
ma ina; Blepha = Blepha idophyllum densi olium; high-al = high-al i ude; James = Jamesoniella 2181
colo a a; mid-al = mid-al i ude; Sanionia = Sanionia uncina a. 2182
6.3.3. Impac o in asions 2183
G emmen (1997) es ima ed ha in asion by g asses (plo s domina ed by Ag os is s oloni e a bu wi h 2184
p esence o o he aliens) led o a 50% dec ease in na i e ege a ion ichness in in aded d ainage lines. 2185
B yophy e biomass was also 16 imes lowe in hese habi a s, bu he species ichness o 2186
mac oin e eb a es and mi es was highe in in aded a eas (G emmen e al. 1998). A compa ison o 2187
Ma ion and P ince Edwa d Island wi h he unin aded Hea d Island showed ha in asi e sp ing ails 2188
caused a leas a ou - old decline in a e age on he densi y o h ee na i e sp ing ail species (Chown 2189
e al. 2022), bu Gab iel e al. (2001) did no ind a nega i e impac o in asi e sp ing ails on ei he he 2190
ichness o abundance o na i e sp ing ails ac oss 13 habi a s on Ma ion Island. 2191
88
6.4 In e en ions 2192
6.4.1. Inpu —quali y o egula o y amewo k 2193
The PEIs ha e he highes le el o p o ec ion a o ded o any na u al a ea unde Sou h A ican law. 2194
The islands we e decla ed a Special Na u e Rese e in 1995 and a e ese ed p ima ily o scien i ic 2195
esea ch and en i onmen al moni o ing (DFFE 2010). Rec ea ion ac i i ies a e p ohibi ed. The PEIs 2196
we e designa ed a Ramsa We land Si e o In e na ional Impo ance in 2007, and in 2013, he P ince 2197
Edwa d Island Ma ine P o ec ed A ea was o mally decla ed (DFFE 2010). Alien species a e no allowed 2198
o be in oduced o he PEIs. 2199
The NEM:BA A&IS Regula ions (2020) lis 13 o he 48 axa cu en ly p esen (o doub ul) on he 2200
islands, bu wo axa which a e being managed a e no cu en ly lis ed and ou axa which a e lis ed 2201
(and he e o e should be managed) a e no being managed (Table 6.4). None o he species cu en ly 2202
egula ed o he PEIs a e egula ed o mainland Sou h A ica. No isk analyses ha e been pe o med 2203
o axa lis ed on he PEIs (Table S5.2), and, gi en ha ideally he PEIs should be alien- ee, a guably 2204
i is inapp op ia e o isk analyses o be conduc ed solely o he PEIs. An e alua ion o managemen 2205
op ions conduc ed and egula ly upda ed wi hin he scope o he PEIs Managemen Plan would likely 2206
p o ide he necessa y and su icien in o ma ion o guide in e en ions. 2207
Table 6.4. Alien axa lis ed unde he NEM:BA A&IS Regula ions o 2020 o he P ince Edwa d Islands 2208
(PEIs) o o which an e adica ion plan has been de eloped [c . Appendix 7; Wilson (2023)]. Only he 2209
lis ing ele an o he PEIs is included he e. In o ma ion on he implemen ed con ol measu e was 2210
ob ained mainly om he Depa men o En i onmen al A ai s (DEA) and DST-NRF CIB 2012–2013, 2211
las upda ed in 2021, pe sonal communica ion wi h DFFE Specialis P og amme Manage Debbie Mui , 2212
o indica ed o he wise. Technically as he PEIs a e o -sho e islands, he ollowing a e also lis ed as 1b 2213
[Alec o is chuka (Chuka pa idge), O yc olagus cuniculus ( he Eu opean abbi ), Ra us no egicus, 2214
R. a us, and R. anezumi ( he No wegian, b own, and Asian house a espec i ely)] and he ollowing 2215
as 1a [Cap a hi cus (goa ) and Felis ca us (domes ic ca )]. 2216
Scien i ic name
Ve nacula
name
Regula o y
lis ing
In oduc ion
S a us
T ea ed o
moni o ed
No es on con ol implemen ed
Ag os is
cas ellana
ben g ass
1a PEI
1b MI
P esen bu
no
na u alised
Yes
In lo escences a e cu and
bagged, and he emaining pa s
o he plan s sp ayed wi h
he bicide (Debbie Mui pe s.
comm. 22 May 2023)
Ag os is
gigan ea
black ben
g ass
1a
Na u alised
bu no
in asi e
Yes
Mechanical emo al o
abo eg ound biomass and
he bicide applica ion
(Glyphosa e; 2.5% Kilo Max)
Ag os is
s oloni e a
c eeping
ben g ass
1a PEI
1b MI
In asi e
No
None implemen ed (success ul
e adica ion deemed un easible;
G e e e al. 2017)
89
Scien i ic name
Ve nacula
name
Regula o y
lis ing
In oduc ion
S a us
T ea ed o
moni o ed
No es on con ol implemen ed
Alopecu us
genicula us
ma sh
ox ail
1a
Doub ul
(e adica ion
o be
con i med)
Yes
Manual emo al was applied,
assumed o be no longe p esen
since 2012 (G e e e al. 2017)
Ce as ium
on anum
common
mouse-ea
chickweed
1b
In asi e
No
None implemen ed because i is
widesp ead (G e e e al. 2017,
DEA and DST-NRF CIB 2021)
Elymus epens
1
couch g ass
1a
Na u alised
no in asi e
Yes
Mechanical emo al o
abo eg ound biomass and
he bicide applica ion
(Glyphosa e; 2.5% Kilo Max
700g/kg)
Fes uca ub a
c eeping ed
escue
1a
Na u alised
no in asi e
Yes
He bicide applica ion
(Glyphosa e; 2.5 Kilo Max)
Holcus lana us
common
el e g ass
No lis ed
Doub ul
(e adica ion
o be
con i med)
Yes
The species was manually
emo ed in 2012, si e and
su ounding a eas ha e been
moni o ed mon hly since emo al
o de ec any eg ow h o new
plan s
Luzula
mul i lo a
wood ush
1a
Na u alised
no in asi e
Yes
He bicide applica ion
(Glyphosa e; 2.5% Kilo Max). A
gene ic s udy has been
ecommended o con i m ha i
di e s om he na i e
suban a c ic Luzula species (and
so unequi ocally alien)
Mus musculus
house
mouse
1a MI
In asi e
Yes
Bai ed aps a e deployed bo h
ou side and inside he base and
hu s o p o ec ood and human
heal h (Wol aa d pe s. comm.
2022). Mice a e no ye ,
o he wise, subjec o con ol,
al hough an e adica ion is being
planned, namely he ‘Mouse- ee
Ma ion P ojec ’ due o s a in
2025 i enough unds a e aised
Poa p a ensis
Ken ucky
blueg ass
1a PEI
1b MI
In asi e
No
None implemen ed (G e e e al.
2017, DEA and DST-NRF CIB 2021)
Po cellio scabe
Common
ough
woodlouse
No lis ed
Doub ul
(e adica ion
o be
con i med)
Yes
The woodlouse is belie ed o
ha e been success ully e adica ed
in 2012, bu his needs o be
moni o ed o con i ma ion.
E adica ion is ecommended ia
applica ion o py e h oid (Supe
C ackdown)
1Lis ed as Ely igia epens (L.) Des . ex Ne ski (= Ag opy on epens (L.) P. Beau ., Elymus epens (L.) Gould)
unde he A&IS Regula ions o 2020.
90
Scien i ic name
Ve nacula
name
Regula o y
lis ing
In oduc ion
S a us
T ea ed o
moni o ed
No es on con ol implemen ed
Rumex
ace osella
Sheep so el
1a
Na u alised
no in asi e
Yes
Mechanical emo al o
abo eg ound biomass wi h no
he bicide applica ion
(in lo escence is cu and hen
plan pulled) (Debbie Mui pe s.
comm. 22 May 2023)
Sagina
p ocumbens
Bi deye
pea lwo
1b
In asi e
No
None implemen ed (success ul
e adica ion deemed un easible by
G e e e al. 2017), bu he
po en ial o classical biocon ol
is unde in es iga ion.
S ella ia media
Common
chickweed
1a PEI
1b MI
Doub ul
Yes
He bicide applica ion (2.5% Kilo
Max).
2217
6.4.2. Inpu —money spen 2218
Gi en he disc e e na u e o he PEIs and he limi ed numbe o people in ol ed, i should be possible 2219
o es ima e he money spen o con ol in asions. Howe e , no such es ima es ha e been made ye , 2220
in pa as in o ma ion has no been o hcoming. The ollowing in o ma ion is a ailable. The DFFE 2221
budge o he bicides ( wo di e en ypes) and equipmen , including pe sonal p o ec i e equipmen , 2222
o he con ol o alien species on he PEIs 2011–2022 was ZAR 58 664 (see supplemen a y ma e ial 2223
S6.5). The only pes icide applied on Ma ion Island o con ol in e eb a es was dona ed; he alue o 2224
his has no ye been ob ained. In 2006 he e was a speci ic a ge ed e o o con ol he in asi e 2225
plan Elymus epens, whe e abo e-g ound ma e ial and some o he below-g ound hizomes we e 2226
emo ed, and he bicide was applied. The o al cos o he ope a ion was ZAR 201 378 which included 2227
human esou ces as well as helicop e ips o anspo he emo ed biomass. 2228
The majo cos con olling biological in asions on Ma ion island will be he ime o he ECOs. ECOs 2229
pe o m a ious du ies, bu he e is no cu en es ima e a ailable o he ime alloca ed o alien species 2230
moni o ing and con ol. No con inuous con ol (o moni o ing) is possible on P ince Edwa d Island due 2231
o he lack o egula human p esence on he island. 2232
6.4.3. Inpu —planning co e age 2233
The cu en managemen plan de e mines he qua an ine and biosecu i y measu es o be applied o 2234
in oduc ion pa hways, and makes ecommenda ions o he managemen o in asi e species. The 2235
PEIs Managemen Plan includes bo h islands, and so all si es ha e a managemen plan in place. 2236
The e ha e been wo managemen plans de eloped o he PEIs: one published in 1996, and ano he 2237
in 2010 (Ve sion 0.2). The second plan was o icially adop ed by he hen Depa men o 2238
En i onmen al A ai s (DEA) in 2014. Managemen plans we e se o be e ised and upda ed e e y 2239
97
Indica o T end1 Con idence Desi ed
end Cu en s a us and end Ou look
10. Rela i e
in asi e
abundance
↗ low ↘
Mean plan co e on MI 2.6%; no plan s da a o his
indica o on PEI. In e eb a es’ ela i e in asi e abundance
a ies be ween 0–2% o PEI sp ing ails o 28% on MI; o
mi es be ween 8% a PEI and 14% a MI; howe e , he
unce ain y o na i i y s a us o Cillibidae make his
es ima e e y low con idence. Spide s ha e been s udied
only on MI (37% mean ela i e abundance) and he e is no
da a o insec s due o lack o comple e su eys.
Expec ed o inc ease as species sp ead ac oss
la ge ex en s o he island, inc easing island-
wide impac s; bu also expec ed o inc ease as
clima e amelio a ion may make he en i onmen
mo e a ou able o gene alis in ade s.
11. Impac o
in asions ↗ low ↘
Because abundance is inc easing, and because he e a e
some indica ions ha he amelio a ion o clima e on he
PEIs is bene i ing in asi e o e na i e species, he impac is
assumed o inc ease. Li le da a. (Mice ha e inc eased
popula ions, McClelland e al. 2018).
Expec ed o inc ease as species sp ead ac oss
la ge ex en s o he island, inc easing island-
wide impac s; bu also expec ed o inc ease as
clima e amelio a ion may make he en i onmen
mo e a ou able o gene alis in ade s.
12. Quali y o
egula o y
amewo k
↗ high ↗
The cu en managemen plan was de eloped in 2010. The
e adica ion plan is e ised and upda ed e e y yea . The
quali y o he egula o y amewo k is conside ed pa ial.
Regula ions a e in he p ocess o being e ised
and a new Managemen Plan is mean o go ou
o public commen in 2023. The p ocess o
p io i ising managemen a ge s will likely be
mo e e ec i e i decoupled om na ional-le el
egula ions and p ocesses.
13. Money
spen ↗ medium ↗
The DFFE budge o he bicides and equipmen o he
con ol o alien species on he PEIs du ing 2011–2022 was
ZAR 58 664. This is an unde es ima e, as a ull alue was no
p o ided. Fo example, he cos o hou s in es ed by ECOs
on con ol o alien species has no been es ima ed.
A educ ion in o al cos s o in asi e clea ing is
expec ed in line wi h he In asi e Alien Species
managemen plan. Signi ican unds will be spen
in a sho pe iod o ime i he Mouse-F ee
Ma ion P ojec is implemen ed.
14. Planning
co e age ↗ high ↗
All se en ac i e pa hways ha e managemen plans in place.
Alien in asi e species managemen plan complian o
NEMBA egula ions Sec ion 76 (A), Sec ion 70 (1)(2)(3). The
managemen plan co e s Ma ion and P ince Edwa d Island,
so all si es ha e a managemen plan in place, al hough
ou da ed.
E adica ion plan o be upda ed a e second
pa y assessmen (Ap il/May 2023) o include
his o ical and ac i e species si es. A mapping
sys em ha can e lec his o ical and ac i e
con ol me hods will be a ailable. Mapping
sys em can be used o es ima ing inc ease o
dec ease on in asions po en ial, allowing o
adap i e managemen and upda e o e adica ion
plans.

98
Indica o T end1 Con idence Desi ed
end Cu en s a us and end Ou look
15. Pa hways
ea ed → high ↗
All pa hways by which alien species can be in oduced
equi e managemen , and hey a e all being managed
unde s ic biosecu i y measu es.
In o ma ion on biosecu i y b eaches (e.g.,
iden i ica ions) can be used o imp o e p o ocols.
16. Species
ea ed
↘ high ↗
O he 13 lis ed in asi e axa (12 plan species and one
mammal), 8 plan s a e subjec ed o some o m o
managemen (ei he in lo escence cu and bagged and
plan pulled, o he bicide). Fi e po en ially e adica ed
species a e being moni o ed o con i m s a us ( ou plan
species and he isopod). Mice a e only con olled a he
base and hu s. In asi e plan s’ his o ical si es and ac i e
si es a e being mapped and moni o ed.
Con i ma ion o e adica ion o i e species will
only be done i hey ha e no been seen o ou
consecu i e second pa y assessmen s (12 yea s).
I he Mouse F ee Ma ion e adica ion plan goes
ahead in 2025 a con ingency plan a e mass
bai ing mus be implemen ed.
17. Si es
ea ed → high ↗
Ma ion Island is ea ed on a egula basis, howe e P ince
Edwa d Island can only be isi ed e e y ou yea s (bu has
no been isi ed in he las 10 yea s), he e o e he e is no
managemen cu en ly applied on ha si e.
Mapping and moni o ing plan will indica e
his o ical as well as ac i e si es o indica e
e ec i eness o con ol plans.
18.
E ec i eness
o pa hway
ea men s
No
assesse
d
↗ The necessa y quan i a i e da a o assess his indica o a e
no a ailable.
In o ma ion on biosecu i y b eaches (e.g.,
iden i ica ions) can be used o imp o e p o ocols.
19.
E ec i eness
o species
ea men s
↗ high ↗
Many in asi e species a e subjec o some o m o con ol,
and ou comes a e moni o ed. The e a e 11 axa ha a e
e adica ion a ge s, wi h i e ha a e po en ially e adica ed
and ha e become moni o ing a ge s as hey ha e no been
seen o se e al consecu i e yea s. DFFE h ee-yea
assessmen esul s indica e a educ ion in ac i e si es. Fou
widesp ead in asi e plan species a e conside ed
inapp op ia e a ge s o e adica ion, and he e o e a e no
being ea ed.
Mapping and moni o ing p og am will indica e
e ec i eness o con ol p og ammes in u u e.
New con ol echnologies will likely be needed i
cu en widesp ead in asi e axa o he han he
house mouse a e o be e ec i ely con olled.
20.
E ec i eness
o si e
ea men s
↗ high ↗
Second pa y assessmen implemen ed h ee- yea ly a
Ma ion Island o quan i y e ec i eness o ea men s and
possible educ ions o axa popula ions (plan s, isopod and
mice).
Moni o ing plan da a will be used o amend /
upda e in asi e species managemen plan.
99
Indica o T end1 Con idence Desi ed
end Cu en s a us and end Ou look
A. Ra e o
un egula ed
in oduc ion
o new species
→ medium ↘ The a e o in oduc ion has no changed in he las en
yea s.
No change is en isaged. T a ic o, and pa hways
o he islands is no expec ed o change because
he same p o ocol is s ic ly ollowed e e y yea
and is unlikely o change in he nea u u e.
Recen imp o emen s (e.g., no Velc o) and
con inuing wo k on biosecu i y would be needed
i he goal o ze o in oduc ions is o be achie ed.
B. Numbe o
in asi e
species ha
ha e Majo
impac s
→ medium ↘
No new in asi e species ha e been in oduced o he
islands ecen ly, al hough exis ing in ade s a e sp eading
and hei impac s migh ha e inc eased.
Expec a ion is ha cu en ange es ic ed axa
will no be allowed o sp ead, and so any changes
o his will be in e ms o exis ing widesp ead
in ade s inc easing in e ms o he impac s hey
cause o e ime.
C. Ex en o
a ea ha
su e s majo
impac s om
in asions
↗ ↘
Se e al alien species ha e no eached equilib ium wi h he
en i onmen ac oss he PEIs and a e s ill sp eading. Some
o hese ha e Majo impac s (e.g., Sagina p ocumbens).
Expec ed o inc ease as species sp ead ac oss
la ge ex en s o he island, inc easing island-
wide impac s; bu also expec ed o inc ease as
clima e amelio a ion may make he en i onmen
mo e a ou able o gene alis in ade s.
D. Le el o
success in
managing
in asions
→ high ↗
Some managemen ac ions ha e been success ul, and
species a e being moni o ed o con i m e adica ion. The
dis ibu ion o some o he axa has emained s able / been
kep unde con ol. Howe e , a ew axa ha e inc eased in
ex en . So o e all he e is no change, and he le el o
success is pa ial.
Assessmen done in 2023 based on da a om 2020–2022
we e compa ed o p e ious assessmen o indica e changes
and achie emen s o managing in asions.
I success ul, he ‘Mouse- ee Ma ion’ P ojec
would be a signi ican achie emen , and,
al hough less p essing, o he e adica ions would
lead o an inc ease in his indica o .
2359
100
Chap e 7: Gaps 2360
Au ho s: John R. Wilson, Ka elyn T. Faulkne , Lau a Fe nández Winze , Emily J. McCulloch-Jones, 2361
B ian W. an Wilgen, Tsungai A. Zengeya 2362
Key gaps1 2363
• The indica o s de eloped o his epo need o be es ed and aligned o o he go e nmen 2364
epo ing p ocesses. 2365
• The e is insu icien in o ma ion on how in asi e species mo e and a e mo ed a ound Sou h 2366
A ica. A sys em o ack wi hin-coun y dispe sal is equi ed i Sou h A ica is o e ec i ely 2367
manage he sp ead o in asi e species. 2368
• Da a on he p esence, dis ibu ion and abundance o alien species need o be collec ed, colla ed, 2369
and in eg a ed in o na ional and global da abases o acili a e he planning o in e en ions. 2370
• The sys ema ic quan i ica ion o he impac s o biological in asions is needed o acili a e he 2371
p io i isa ion o in e en ions, p o ide a de ensible a ionale o unde pin go e nmen in es men , 2372
and p o ide backg ound o e o s o communica e he se e i y o he issue. 2373
• A comp ehensi e policy, and a s a egy o implemen such a policy, a e needed o guide 2374
in e en ions on biological in asions in Sou h A ica. 2375
• The e icacy o mos in e en ions is no moni o ed in e ms o ou pu s and ou comes. Fo mal 2376
p og ams ha moni o p og ess owa ds educing he nega i e impac s o in asions would allow 2377
o con ol measu es o be compa ed and imp o ed. 2378
• Se e al gaps speci ic o he P ince Edwa d Islands we e iden i ied (e.g., in e ms o iden i ying 2379
incu sions, and he need o close co-ope a ion be ween managemen and esea ch), hese a e 2380
discussed in Chap e 6. 2381
• S akeholde engagemen is needed o e alua e how he epo is cu en ly used, and wha can be 2382
done o imp o e up ake and be e add ess s akeholde needs. 2383
7.1 P ocess o iden i ying gaps 2384
We iden i ied gaps om wo sou ces. 1) Gaps iden i ied in he p e ious epo s we e e alua ed, and 2385
p og ess (o lack he eo ) o add ess hese a e highligh ed (Tables S6.1, S6.2). Tex om he chap e 2386
on gaps om he second epo is included below and upda es no ed. 2) Gaps iden i ied by ex e nal 2387
e iewe s and he Re e ence and Ad iso y Commi ee (RAC) we e e alua ed. These a e lis ed in 2388
sec ion 7.8 below. 2389
1All bu he las wo key gaps a e he same as he 2nd epo as, while he e has been p og ess on some o
hese, none a e ully add essed ye (see Tables S7.1, 7.2)
101
We ecognise ha he nex comp ehensi e epo will need o ully examine hese gaps and should 2390
sys ema ically e alua e gaps in epo ing and in o ma ion. Se e al o he sou ces o gaps o me hods 2391
o iden i y gaps we e lagged and will o m a co e pa o u u e epo s. Gaps we e iden i ied du ing 2392
he IPBES IAS Global Assessmen , speci ically able SPM.A1 in one o he inal d a s o he assessmen 2393
add essed gaps. Howe e , as he de ails will only become publicly a ailable in Oc obe 2023, hese 2394
gaps could no be assessed du ing his epo cycle. I is also planned o ha e b oade s akeholde 2395
consul a ion as pa o he ini ia ion o he nex comp ehensi e epo o de e mine how his epo 2396
is and can be used (c . a ecen end-use su ey was conduc ed as pa o Sou h A ica’s Na ional 2397
Biodi e si y Assessmen o iden i y opics ha should be he ocus o u u e assessmen s). Finally, he 2398
epo will need o look a indica o s ha a e adop ed as pa o he Kunming-Mon eal Global 2399
Biodi e si y F amewo k (GBF) (see Box 1.2). 2400
7.2 Indica o s—imp o ing how in asions a e measu ed and p o iding a link o o he epo s 2401
The indica o amewo k as a whole was es ed using he P ince Edwa d Islands (Chap e 6). This wo k 2402
has highligh ed some issues wi h he indica o s (cu en ly add essed h ough edi s o he me ada a o 2403
he species lis s). Addi ional indica o s, ha link o he GBF, a e unde -de elopmen , and a ecen 2404
s udy has iden i ied essen ial p ope ies o such indica o s (Vicen e e al. 2022). As he epo s 2405
con inue, and in ligh o in e na ional de elopmen s, he indica o amewo k will be adjus ed, in 2406
pa icula wi h e ised ac shee s p oduced as pa o he nex epo . 2407
7.3 Pa hways— acking in asions ac oss Sou h A ica 2408
The e is s ill a need o de elop a amewo k o ca ego ise pa hways wi hin a coun y as he e a e 2409
subs an i e quan i a i e and quali a i e di e ences be ween in oduc ions o and wi hin he coun y. 2410
In he absence o such a amewo k, in o ma ion on how species a e dispe sing wi h he coun y, and 2411
p ocesses o educe such dispe sal, in asi e species, once es ablished in he coun y, will con inue o 2412
sp ead apidly and impac s will inc ease. Some p og ess has been made o adjus he pa hway 2413
classi ica ion scheme o Sou h A ica (c . Faulkne e al. 2020), and his will be implemen ed in u u e. 2414
7.4 Species & Si es—mapping in asions in space and o e ime 2415
The sou he n A ican Plan In ade s A las (SAPIA) was las upda ed in Ma ch 2020, and he e has been 2416
no da a collec ion o colla ion since. This cessa ion in SAPIA ep esen s a majo h ea o Sou h A ica’s 2417
abili y o ack spa ial pa e ns in plan in asions o e ime, no ing ha such sys ema ic and e i ied 2418
moni o ing o da a can only be pa ially add essed h ough ad hoc ci izen science eco ds. As no ed in 2419
he second epo , he e a e signi ican gaps in ou knowledge o he p esence and dis ibu ion o axa 2420
no cu en ly co e ed by speci ic a lasing p ojec s. Remo e sensing s ill p omises much as an app oach 2421
102
o imp o ing dis ibu ion da a, bu has no , ye , deli e ed angible esul s ha can be used in his 2422
epo . The e con inue o be e y ew eliable da a sou ces on he ela i e abundance (co e , biomass 2423
o popula ion size) o alien species a speci ic si es. De ailed maps a na ional scale and local scale 2424
es ima es o he impac o in asions a e needed o app op ia ely p io i ise in e en ions ac oss si es 2425
and so ha in e en ions can be adjus ed o espond o in asions be o e such in asions a e 2426
widesp ead and damaging. 2427
7.5 Species & Si es—de e mining he impac s and cos s 2428
Fo he go e nmen o con inue o in es subs an ial esou ces in managing biological in asions he 2429
bene i s ha in e en ions b ing in alle ia ing he nega i e impac s caused o all sec o s o Sou h 2430
A ican socie y and o he coun y’s unique biodi e si y mus be clea ly documen ed. Da a on impac s 2431
a e essen ial i con ol measu es a e o be p io i ised and o ack he e ec i eness o in e en ions 2432
(e.g., in e ms o inc easing he esilience o Sou h A ican ci ies, owns, and u al communi ies o 2433
d ough s and i es; ensu ing ag icul u al sus ainabili y; and p o ec ing ou na u al capi al o u u e 2434
gene a ions). While he de elopmen o a wo k low and he colla ion o economic es ima es 2435
ep esen s a signi ican ad ance, a sys ema ic me hod o assessing he impac s o biological in asions 2436
a a si e is s ill needed (i.e., he combined impac s o all alien species p esen ). Such assessmen s will 2437
equi e di ec ed esea ch o es ima e he impac s o biological in asions in economic and social e ms. 2438
Conside a ion should also be gi en o he alue o long- e m moni o ing o ack impac s and how 2439
hey change in esponse o di e en in e en ions. 2440
7.6 In e en ions— he need o an o e -a ching policy and s a egy 2441
Sou h A ica s ill does no ha e a comp ehensi e o e a ching na ional go e nmen policy on biological 2442
in asions. A na ional s a egy on biological in asions has been d a ed, bu , as o May 2023, has no 2443
gone o public commen . This ‘policy acuum’ has been lagged as an impo an ac o limi ing he 2444
e ec i eness o pas e o s o con ol biological in asions (Lukey and Hall, 2020). A comp ehensi e, 2445
e idence-based policy on biological in asions would cla i y he go e nmen ’s posi ion, guide decision-2446
make s when implemen ing legisla ion, and assis he legisla u e when making and amending ele an 2447
laws. C ucially such a s a egy o policy will need o be cognisan o ecen in e na ional ag eemen s 2448
(e.g., he GBF) and bes in e na ional p ac ice (e.g., he IPBES Thema ic Assessmen o In asi e Alien 2449
Species and hei Con ol due o be eleased Oc obe 2023). Wi hin his con ex , he iming o an 2450
o e -a ching na ional s a egy o Sou h A ica is pa icula ly p opi ious. The de elopmen o a 2451
comp ehensi e science-in o med s a egy p omises o p o ide impe us o add ess all he gaps 2452
iden i ied in his epo and ensu e we ha e a Sou h A ica p o ec ed om he ha m caused by 2453
biological in asions o he bene i o he en i onmen and human li elihoods. 2454

103
7.7 In e en ions—measu ing he e ec i eness o in e en ions 2455
The e con inues o be no long- e m plans o moni o ing in e en ions in e ms o how hey educe 2456
biological in asions and hei nega i e impac s, and i is unclea how he collec ion and epo ing o 2457
accu a e moni o ing da a is incen i ised o penalised i i is no o hcoming. Ve y ew esea ch 2458
p ojec s ha e assessed he impac o pa icula policies—a sys emic ocus on moni o ing and 2459
e alua ion ac oss he boa d would help bo h o demons a e he impac o in e en ions and o 2460
inc ease he e icacy o he in e en ions hemsel es. Good da a on moni o ing cos s money, bu is a 2461
p e equisi e o e ec i e adap i e managemen and ensu ing new echnologies a e used 2462
app op ia ely. Such moni o ing p o ides signi ican e u ns on in es men . 2463
7.8 Sugges ions o ex ensions o he scope o he epo 2464
Va ious eques s ha e been made o include addi ional in o ma ion in u u e epo s. 2465
• The con ibu ion o wo k on biological in asions o human capaci y de elopmen in he 2466
biodi e si y sec o including h ough pos g adua e esea ch, o he skills de elopmen (e.g., 2467
aining cou ses), and seconda y and e ia y cou ses. 2468
• The social bene i s c ea ed h ough in es men s in wo k on and con ol o biological in asions, 2469
including numbe o jobs c ea ed and alue-added p oduc s. 2470
• The po en ial impac o in asions and he cos s o ine ec i e (o a lack o ) in e en ions, i.e., 2471
bo h a p ojec ion o likely u u e impac s and an e alua ion o he coun e - ac ual i di e en 2472
in e en ions had been implemen ed. 2473
• Imp o ed p esen a ion o impac s and managemen in economic e ms. 2474
• The esou ces a ailable o p ac i ione s, manage s and land-owne s (e.g. ele an books, 2475
iden i ica ion cha s, apps, websi es e c.); including he de elopmen and up ake o e ec i e 2476
ools o guidelines o managemen (e.g., o he bicides). 2477
• An e alua ion o public awa eness and pe cep ions o biological in asions, hei managemen , 2478
and how hese change o e ime. 2479
• An assessmen o communi ies o p ac ice and he deg ee o which he e is in eg a ed 2480
go e nance. 2481
In a ew cases he exis ing indica o s a e app op ia e o cap u e hese issues, al hough he issues ha e 2482
ei he no been e alua ed o da e o he e is a lack o da a. In many o he cases, hese issues canno 2483
be cap u ed by he cu en se o indica o s. Howe e , a majo conclusion o his, and p e ious epo s, 2484
is ha how in e en ions educe o amelio a e he damage caused by in asions (i.e., ou comes) is 2485
a ely moni o ed. As a consequence, he impac s o biological in asions ha e no been alle ia ed as 2486
104
much as hey could ha e been o i in e en ions a e e ec i e i has is no possible o demons a e 2487
his. The epo needs o p o ide a balance be ween ensu ing he e is a ocus on biological in asions 2488
(as pe he emi ) and looking a in asions in he b oade con ex (wi hou eplica ing o he epo ing 2489
p ocesses). Mo eo e , ex ending he epo scope will bo h ex end he esou ces equi ed (e.g., o al 2490
cos o p oduce he epo ) and he expe ise needed o achie e his (e.g., economis s and social 2491
scien is s). This will be an impo an challenge o he nex comp ehensi e epo , and an impo an 2492
ocus o he planned s akeholde consul a ion. 2493
2494
105
Acknowledgemen s 2495
To be included in he inal e sion when all con ibu ions ha e been ecei ed 2496
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