2019 Status of Ameralik caribou population, South region, West Greenland. Technical Report No. 125

1
2019 S a us o Ame alik ca ibou
popula ion, Sou h egion,
Wes G eenland
Technical Repo No.125, 2023
Pinngo i ale i ik – G eenland Ins i u e o Na u al Resou ces
2
Ti le: 2019 S a us o Ame alik ca ibou popula ion, Sou h egion,
Wes G eenland
Au ho s: Ch is ine Cuyle 1, Tiago A. Ma ques2, Iú i J.F. Co eia3, Aslak
Jensen4, Hans Mølgaa d5 and Jukka Wagnhol 6
1 Pinngo i ale i ik – G eenland Ins i u e o Na u al Resou ces, P.O.
Box 570, 3900 Nuuk, G eenland
2 CREEM, Uni e si y o S And ews, School o Ma hema ics and
S a is ics, Sco land
3 Uni e si y o Lisbon, Facul y o Sciences, Po ugal
4 Sol iaq 15, 3900 Nuuk, G eenland
5 P.O. Box 122, 3911 Sisimiu , G eenland
6 Tusass, P.O. Box 1002, 3900 Nuuk, G eenland
Se ies: Technical Repo No. 125, 2023
Da e o publica ion: 06 Ap il 2023
Publishe : Pinngo i ale i ik – G eenland Ins i u e o Na u al Resou ces
Financial suppo : Go e nmen o G eenland and Pinngo i ale i ik – G eenland
Ins i u e o Na u al Resou ces
ISBN: 978-87-972977-8-0
ISSN: 1397-3657
EAN: 9788797297780
Co e pho o: Ch is ine Cuyle : 11 camou laged ca ibou, Ame alik
popula ion, nea line ansec 110, Sou h egion.
Ci ed as: Cuyle , C., Ma ques, T.A., Co eia, I.J.F., Jensen, A.,
Mølgaa d, H. & Wagnhol , J. 2023. 2019 S a us o Ame alik
ca ibou popula ion, Sou h egion, Wes G eenland.
Pinngo i ale i ik – G eenland Ins i u e o Na u al
Resou ces. Technical Repo No. 125. 109 pp.
Con ac add ess: The epo is only a ailable in elec onic o ma .
PDF- ile copies can be downloaded a his homepage:
h ps://na u .gl/ o skning/ appo e /
Pinngo i ale i ik – G eenland Ins i u e o Na u al Resou ces
P.O. Box 570, 3900 Nuuk, G eenland
Phone: +299 36 12 00
E-mail: in o@na u .gl
www.na u .gl
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2019 S a us o Ame alik ca ibou
popula ion, Sou h egion,
Wes G eenland
By
Ch is ine Cuyle 1, Tiago A. Ma ques2, Iú i J.F. Co eia3, Aslak Jensen4,
Hans Mølgaa d5 and Jukka Wagnhol 6
1 Pinngo i ale i ik –G eenland Ins i u e o Na u al Resou ces, P.O. Box 570, 3900 Nuuk, G eenland
2 CREEM, Uni e si y o S And ews, School o Ma hema ics and S a is ics, Sco land
3 Uni e si y o Lisbon, Facul y o Sciences, Po ugal
4 Sol iaq 15, 3900 Nuuk, G eenland
5 P.O. Box 122, 3911 Sisimiu , G eenland
6 Tusass, P.O. Box 1002, 3900 Nuuk, G eenland
Technical Repo No. 125, 2023
Pinngo i ale i ik – G eenland Ins i u e o Na u al Resou ces
4
[Emp y page]
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Table o Con en s
Summa y (English)……………………………………… 8
Eqikkaaneq (kalaallisu ) ………………………………. 9
Resumé (dansk)……………………………………….... 11
In oduc ion ……………………………………………. 13
Me hods …………………………………………………. 15
Resul s…………………………………………………… 23
Discussion ……………………………………………… 43
Acknowledgemen s……………………………………. 51
Li e a u e ci ed ………………………………………… 52
Figu es
1.
Bo de s o he Sou h egion, …
Page 13
2.
A ea co e ed by 2019 ca ibou su ey o no he n po ion o Sou h egion…
Page 17
3.
The 25 line ansec s used in he 2019 su ey o Sou h egion…
Page 19
4.
Loca ion and g oup size o ca ibou de ec ions ( unca ed da a) …
Page 25
5.
Explo a o y analysis: numbe o de ec ions by sub-a ea and line ansec …
Page 26
6.
Explo a o y analysis o g oup size dis ibu ion among de ec ions…
Page 27
7.
Explo a o y analysis o ca ibou encoun e a e pe line ansec …
Page 27
8.
Obse e e ec : his og ams: de ec ed dis ances o he h ee obse e s …
Page 28
9.
No. ca ibou de ec ions pe co a ia es: heli.side, isibili y & camou lage …
Page 29
10.
No. ca ibou de ec ions pe co a ia es: ege a ion/g ound o boulde s…
Page 29
11.
No. ca ibou de ec ions pe co a ia es: sola gla e and dead g ound…
Page 30
12.
Summa y o he equency o ele a ions lown as well as helicop e speed…
Page 30
13.
His og am o obse ed ca ibou dis ances o non- unca ed and unca ed…
Page 31
14.
His og am o Hal -no mal wi h Visibili y as co a ia e o de ec ed …
Page 34
15.
Es ima ed p obabili ies o de ec ion o each obse ed g oup size…
Page 34
16.
Ca ibou densi y (le ) and abundance ( igh ) es ima es wi h ...
Page 35
17.
Obse ed equency o cow-cal pai s o 96 g oups o which…
Page 40
18.
Pas and p esen ca ibou popula ion size es ima es wi h con idence …
Page 43
19.
Pas and p esen ca ibou densi y es ima es o he Ame alik popula ion …
Page 44
20.
Pas and p esen la e win e cal (age 10-mon h) ec ui men …
Page 46
21.
Pas and p esen la e win e bull o cow a ios o he Ame alik …
Page 47
22.
Place names used ega ding he no he n po ion o he Sou h egion …
Page 55
23.
Six ca ibou, o which i e a e eadily isible. All a e wi hin 75 m …
Page 56
24.
Six camou laged ca ibou. Some a e isible on a snow pa ch, bu o he s …
Page 56
25.
Se en camou laged ca ibou. None a e eadily isible agains he mix …
Page 57
26.
Th ee camou laged ca ibou. Despi e ull sunshine, none a e eadily …
Page 57
27.
11 camou laged ca ibou. Few a e eadily isible agains he mix …
Page 58
28.
35 camou laged ca ibou. None a e eadily isible agains he mix …
Page 58
29.
15 camou laged ca ibou. Despi e ull sunshine, none a e eadily isible …
Page 59
30.
31 camou laged ca ibou. None a e eadily isible agains he mix o …
Page 59
31.
17 camou laged ca ibou. None a e eadily isible agains he mix o …
Page 60

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32.
Se en camou laged ca ibou. Gi en he s ong sunshine causing deep …
Page 60
33.
Six camou laged ca ibou a he sou h end o he lake, Iso ua suk. …
Page 61
34.
Two g oups camou laged ca ibou (n= 3+17), sou h end lake Iso ua suk…
Page 61
35.
Fi e camou laged ca ibou, sou h end o lake, Iso ua suk. Despi e …
Page 62
36.
Twel e camou laged ca ibou, eas side o lake, Iso ua suk. Despi e …
Page 62
37.
Nine camou laged ca ibou among dwa sh ub, eas side lake …
Page 63
38.
Fi e camou laged ca ibou, eas side o lake, Iso ua suk. Despi e …
Page 63
39.
Xe ic inland sub-a ea, illus a ing ege a ion poking h ough hin snow …
Page 64
40.
Loca ion o a c ic ox (blue phase) indica ed by blue ci cle.
Page 64
41.
One camou laged e al sheep in he o eg ound jus le and below …
Page 65
42.
One e al sheep obse ed jus no h o he mou h o Aus mannadalen …
Page 65
43.
Plo sampling g id example o o al a ea A di ided in o smalle plo s…
Page 66
44.
Example o a pa ch o und a wi h he ansec in he middle…
Page 69
45.
Hal -no mal ( op ow) and haza d- a e (bo om ow) de ec ion unc ions…
Page 71
46.
Possible shapes o he de ec ion unc ion when cosine adjus men s a e….
Page 72
47.
A good model o he de ec ion unc ion should ha e a shoulde …
Page 75
48.
Coas al Lowlands sub-a ea in backg ound beyond mou h o Bukse jo d …
Page 80
49.
Coas al Lowlands sub-a ea, iew eas owa ds bo de ing moun ains.
Page 80
50.
Coas al Lowlands sub-a ea, wes end line ansec 127, iew is no h.
Page 80
51.
Glacial Moun ains sub-a ea, I oqqa miu Kange lua sunngua …
Page 81
52.
Glacial Moun ains sub-a ea, sou h o line ansec 122 and wes o 117 …
Page 81
53.
Glacial Moun ains sub-a ea, middle po ion o line ansec 123, iew …
Page 82
54.
Glacial Moun ains sub-a ea, i e alley, Qoo usussuaq, which is jus …
Page 82
55.
Glacial Moun ains sub-a ea, eas end o line ansec 123, illus a ing …
Page 83
56.
Glacial Moun ains sub-a ea, he alley and lake, Eqalui , an a ea a ypical …
Page 83
57.
Xe ic inland sub-a ea, line ansec 101, iew eas , no e hin snow laye
Page 84
58.
Xe ic inland sub-a ea, line ansec 102, iew wes , no e hin snow laye .
Page 84
59.
Xe ic Inland sub-a ea, app oaching eas end line ansec 103, iew eas .
Page 85
60.
Xe ic Inland sub-a ea, eas end line ansec 103, iew no h.
Page 85
61.
Xe ic inland sub-a ea, line ansec 104, sou h o Kapisilli , iew is sou h.
Page 86
62.
Xe ic Inland sub-a ea, iew no h illus a ing mou h o b oad b aided …
Page 86
63.
Xe ic Inland sub-a ea, eas end o line ansec 106, iew wes ac oss …
Page 87
64.
Xe ic Inland sub-a ea, line ansec 107, iew eas , no e hin snow laye …
Page 87
65.
Xe ic Inland sub-a ea, iew no heas o e Nuna aa suk and a ea o line …
Page 88
66.
Xe ic Inland sub-a ea, line ansec 108, Nuna aa suk, iew eas . No e, …
Page 88
67.
Xe ic Inland sub-a ea, a ound he wes end o line ansec 110, ou …
Page 89
68.
Xe ic Inland sub-a ea, a ound he eas end o line ansec 110, wo …
Page 89
69.
Xe ic inland sub-a ea jus no h o line ansec 112 and in p oximi y o …
Page 90
70.
Xe ic Inland sub-a ea, iew no h o e he landscape and condi ions on …
Page 90
71.
Xe ic Inland sub-a ea, a ound he middle o line ansec 113, se en …
Page 91
72.
Xe ic Inland sub-a ea, alley a eas end o line ansec 113, en ca ibou …
Page 91
73.
Xe ic inland sub-a ea, line ansec 114, eas o lake, Iso ua suk, iew …
Page 92
74.
Xe ic inland sub-a ea, eas end o line ansec 114, iew no h, illus a ing...
Page 92
75.
Xe ic Inland sub-a ea, while lying line ansec 116. Abo e illus a es …
Page 93
76.
Xe ic inland sub-a ea, eas end line ansec 117, a he G eenland Ice …
Page 94
77.
Xe ic inland sub-a ea, line ansec 117, a lake ha emp ied, iew no h.
Page 94
7
78.
Xe ic inland sub-a ea, illus a ing condi ion on he line ansec 118, …
Page 95
79.
‘Finding Waldo’ camou lage condi ions, Xe ic inland sub-a ea, eas end …
Page 95
80.
Xe ic inland sub-a ea, eas end line ansec 119 a sho e o lake, Ilulialik …
Page 96
81.
Xe ic inland sub-a ea, iew o SW end o he lake, Ilulialik and he eas …
Page 96
82.
His og ams o de ec ed dis ances supe imposed wi h es ima ed de ec ion...
Page 99
83.
Loca ions o he ou lakes obse ed o ha e ecen ly emp ied, be o e …
Page 100
84.
Small lake in Cen al egion, Uja assui sub-a ea, ha ecen ly emp ied in …
Page 101
85.
Emp ied la ge lake in Sou h egion, Xe ic Inland sub-a ea, illus a ing …
Page 101
86.
Recen ly emp ied pond, Aus mann je n, nea eas end o line ansec 112…
Page 102
87.
La ge unnamed lake in Sou h egion, Xe ic Inland sub-a ea, on he no h …
Page 103
88.
The h ee obse e s, D . C. Cuyle … Aslak Jensen… Hans Mølgaa d …
Page 105
89.
AS350 Helicop e iewing windows o he le and igh sides, …
Page 106
Tables
1.
La e win e popula ion pa ame e s, Ame alik ca ibou popula ion…
Page 14
2.
Summa y o unp ocessed esul s: Su ey o Ame alik ca ibou popula ion…
Page 24
3.
Model compa ison ac oss h ee Con en ional Dis ance Sampling models…
Page 32
4.
Encoun e a e (ER) es ima es pe sub-a ea (s a um) o ca ibou g oups…
Page 35
5.
Es ima es o abundance pe sub-a ea (s a um) o he Ame alik ca ibou …
Page 35
6.
Es ima es o densi y pe sub-a ea (s a um) o he Ame alik ca ibou …
Page 35
7.
Mo emen o non-mo emen o ca ibou eac ing o helicop e ly-by…
Page 36
8.
De ails o mo emen o non-mo emen o ca ibou eac ing o helicop e …
Page 37
9.
Demog aphics o Ame alik ca ibou popula ion, Sou h egion. Ma ch 2019.
Page 38
10.
G oup size ela i e o composi ion (demog aphic da ase ), Ame alik…
Page 40
11.
App oxima e ele a ions o ca ibou g oups obse ed…
Page 41
12.
Commonly used key unc ions and se ies expansions o de ec ion unc ion.
Page 70
13.
De ec ion unc ion pa ame e s’ es ima es.
Page 99
14.
Popula ion ca ibou popula ion es ima es & minimum coun s o Wes …
Page 108
Appendices
1.
Place names o he Sou h egion
Page 55
2.
Pho os o camou laged ca ibou (and ox) obse ed Ma ch 2019
Page 56
3.
Fe al sheep (O is a ies) nea Kuussuaq (Aus mannadalen) 14 Ma ch 2019
Page 65
4.
S a is ical me hods behind Dis ance Sampling
Page 66
5.
Dis ance Sampling Assump ions – sho summa y
Page 79
6.
Pho os Sou h egion ae ial su ey condi ions, Ma ch 2019
Page 80
7.
His og ams o de ec ed dis ances
Page 97
8.
Glacie bounded lakes ha ecen ly emp ied, Ma ch 2019
Page 100
9.
Recommenda ions o imp o ing u u e su eys
Page 104
10.
Recen ca ibou popula ion es ima es & minimum coun s o Wes G eenland
Page 108
Raw da a may be accessed by con ac ing Pinngo i ale i ik – G eenland Ins i u e o Na u al Resou ces,
Depa men o Mammals and Bi ds.
8
Summa y
This epo p esen s esul s om he ae ial su ey ca ied ou by helicop e in
ea ly Ma ch 2019, o he Ame alik ca ibou popula ion inhabi ing he
no he n po ion o he Sou h egion in Wes G eenland. This popula ion was
las su eyed in Ma ch 2012, making new es ima es o abundance and densi y
necessa y. In 2001 and 2006 su ey me hod was s ip ansec coun s. In 2012,
me hods changed o Dis ance Sampling. The Ma ch 2019 helicop e su ey
again used Dis ance Sampling me hods.
Fo Ma ch 2019, he Ame alik ca ibou popula ion abundance was es ima ed
a 19,503 ca ibou (95% CI: 12,404 – 30,665; CV = 0.219; SE = 4268), wi h densi y
4.2 ± 0.9 ca ibou/km2 (95% CI: 2.6–6.6). O e all su ey co e age was 9.7%
( unca ed da a), which is a subs an ial imp o emen om he 2.15% co e age
o 2001 and 2006 s ip ansec coun su eys. Fu he , i is e en imp o ed
ela i e o 8.6% co e age o he 2012 Dis ance Sampling sys ema ic ansec s.
Despi e 18 yea s o ha es managemen aimed a con olling ca ibou
abundance and densi y, he Ma ch 2019 Ame alik ca ibou popula ion size is
la ge and appea s o ha e inc eased 67% since 2012. The 2012 and 2019
su eys we e simila in co e age and me hod. The e is li le o e lap in he
Con idence In e als o he 2012 and 2019 popula ion es ima es. Fu he , he
2019 CV (0.22) indica es good p ecision in he 2019 popula ion es ima e. The
h ee combined make i easonable o assume a end o inc easing popula ion
size o e he 2012-2019 pe iod.
The densi y es ima e o he Ame alik popula ion was 4.2 ca ibou pe km2 in
a ea o su ey e o . This alue is much g ea e han he managemen
ecommended a ge o 1.2 ca ibou pe km2 (Kingsley & Cuyle 2002, Cuyle
e al. 2007). A almos ou - old he a ge densi y, Xe ic Inland’s 5.8
ca ibou/km2 may ha e in luenced he obse ed poo 2019 cal ec ui men
and sex a io (below). Exceeding he a ge ca ibou densi y is assumed o aise
he isk o o e g azing and hus decline in ca ibou abundance.
Rela i e o he 2006-2012 pe iod, la e-win e cal pe cen age was simila ,
howe e , cal ec ui men declined somewha om p e ious alues. In
con as , he 2019 sex a io o 22 bulls pe 100 cows was poo and conside ably
lowe han p e ious alues, i.e., 83, 81, 62 in 2001, 2006, 2012, espec i ely, o
animals age > 1-yea . Popula ion end beyond 2019 is unce ain, and he e is
9
always he possibili y o u u e ca as ophic s ochas ic e en s, including
ex eme wea he and pa hogen ou b eaks.
En i onmen al condi ions du ing he 2019 su ey p o ided ex ao dina y
camou lage o ca ibou. Pooling en i onmen al co a ia es in o a single index
o camou lage will imp o e de ec ion unc ion modelling. Skilled obse e s
and lying helicop e low and slow we e c i ical ac o s pe mi ing de ec ion
o ca ibou, speci ically because 17% o all g oups emained s a iona y.
Beyond popula ion pa ame e s, esul s o in e es included ela i ely high
ele a ions, mean 647 m, used by he Ame alik ca ibou popula ion in ea ly
Ma ch. This e lec s he ela i e sca ci y o low ele a ions in he egion and
likely also a oidance o human dis u bance in lowlands. Fu he , and in
con as o o he ca ibou popula ions in Wes G eenland, mos (92%) cows
possessed an le s in he Ame alik popula ion.
Eqikkaaneq (kalaallisu )
Uani nalunaa usiami saqqummiunneqa pu nunap immikkoo uani
u assiissu inik aqu si iusumi qulimiguulik a o lugu ma sip
aalla ilaa ne ani 2019-imi u unik kisi sine ni ine ne i . Tu u aakku
pineqa u nuna a ki aa a kuja aa a a annaa ungaani uumasuuppu .
Tu u oqa igiiaa kingulle mik kisinneqa amik pe iuseq a o neqa oq
assaa oq, qulimiguulimmi akusa aalajange simasumik kisinneqa a ne a ,
aaguu eqa inneqa oq Dis ance Sampling me hods. Pe iuseq ma s 2019-imi
kisi sisoqa ne ani aamma a o neqa poq.
Ame alimmi u u ma s 2019 19.503 -nik (95%-kon idensin e al: 12.404 –
30.665; a ia ionskoe icien = 0,219; nalinginnaasumik nikingassu aasa oq
s anda e o = 4268), ame lassuseqa nissaa missiliuunneqa poq,
naa so suine igullu u u k ad a kilome e -imu , km2-imu ,
eqimassuseqa nissaa 4.2 ± 0.9 u u /km2 (95% CI: 2,6–6,6)
aalajangiunneqa poq. Nuna kisisi iusoq qulangiuaa neqa o lu 9.7%-iu oq
( unke ede da a), assa nuna anne une ujussuaq 2001-mi 2006-milu
kisi si igineqa unu sanilliullugu. Taamanikkumu sanilliullugu
pi sanngo iaa 8,6 %-iumma , assa 2012-imu sanilliussilluni.
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o he yea - ound ice- ee Da is S ai and he low-p essu e oceanic s o m
sys ems ha sweep in om he sou hwes . Howe e , he clima e becomes
inc easingly d y con inen al as one mo es eas owa ds he G eenland Ice
Cap. The inland o he no he n po ion o he Sou h egion is d y owing o
he 1500–2000 m ele a ions associa ed wi h he Se milik jo d, Se meq glacial
ongue and mul iple glacie s. See Appendix 1 o place name de ails. The high
ele a ions physically block he oceanic s o m sys ems, c ea ing a p ecipi a ion
shadow on he no heas e n side making an al eady d y a ea uly xe ic
(Appendix 2, Figs. 25-38; Appendix 6, Figs. 57-79).
In addi ion o ca ibou, he e a e jus h ee wild mammals p esen in he Sou h
egion: a c ic ha e (Lepus a c icus Rhoads), a c ic ox (Vulpes lagopus Linnaeus),
and ecen ly muskoxen (O ibos moscha us Zimme mann) (Cuyle e al. 2016).
The a c ic ox is he only e es ial mammalian p eda o , as la ge mammalian
p eda o s a e absen . In addi ion o he h ee wild mammals, e al domes ic
sheep (O is a ies), ha e main ained a small p esence in Aus mannadalen o
se e al decades (Cuyle e al. 2016) (Appendix 3). These o igina e om sheep
a ming a emp s nea he illage o Kapisilli . The ecen occu ence o
muskoxen was h ough na u al emig a ion om he popula ion inhabi ing he
No h egion (ca. 66°–67°45’N; 49°30’–54°W) o Wes G eenland. Animals
expanded sou hwa d, i s in o he Cen al egion and la e in o he
Nuna a ssuaq a ea o he Sou h egion (Cuyle e al. 2016). Since 2012,
spo adic sigh ings o muskoxen ha e also been epo ed on he Kange lua
(wes o Kapisilli ), and e en o he sou h sho e o he Ame alia a m o he
Ame alik Fjo d (Cuyle unpublished). Expansion is possible because he
egion bo de s a e semi-pe meable pe mi ing limi ed animal mo emen
be ween adjacen egions. Ne e heless, he bo de s a e assumed e ec i e
ba ie s p e en ing mass animal mo emen s (Linnell e al. 2000).
The Sou h egion (ca. 63°30’–64°30’°N; 49°–51°40’W) lies comple ely wi hin
Nuuk Kommunia. G eenland’s capi al ci y, Nuuk, wi h ca. 18,800 inhabi an s,
is si ua ed nea he mou h o Nuuk jo d in he no hwes e n ip o his
egion. Abou 75 km eas o Nuuk in an a m o he Nuuk jo d lies Kapisilli , a
illage o ca. 52 people. Aside om he c ew manning he Bukse jo d hyd o
powe s a ion he e a e no o he pe manen se lemen s in he no he n
po ion o he Sou h egion, which is seasonally ice- ee and co e s an a ea o
7,000–8000 km2, including lakes, i e s, and islands (Cuyle e al. 2003, 2007,
2016). The no he n bo de is p o ided by he Nuuk jo d. The sou he n
bo de is delinea ed by he Se meq glacial ongue and Se milik jo d. The

17
wes e n bo de is he pe manen ly ice- ee seacoas o he Da is S ai , and
he eas e n bo de is he G eenland Ice Cap.
Figu e 2. A ea co e ed by 2019 ca ibou su ey o no he n po ion o Sou h egion (4,676 km2), which
is inhabi ed by he Ame alik ca ibou popula ion. Th ee di e en colou s illus a e he h ee sub-a eas,
designa ed as Coas al lowland, Glacial moun ains, and Xe ic inland. G eenland’s capi al ci y, Nuuk, is
he ed diamond a he ip o he hin long g ey peninsula in uppe le co ne .
A compa ison o igu es 1 and 2, illus a es ha he ae ial su ey e o in 2019
did no co e all he Sou h egion’s no he n po ion. This con as s wi h he
2001, 2006 and 2012 su eys. In 2019, he no hwes sec ion was omi ed
owing o ecen ly pe mi ed snowmobile use in g ey a ea (Fig. 2), as
dis u bance by snowmobile was expec ed o al e ca ibou dis ibu ion. The
2019 su ey concen a ed e o o only hose a eas whe e snowmobile use
con inued o be p ohibi ed in he open land. This was an a ea o 4,676 km2,
(excluding lakes, i e s, sand, glacie s, and islands), which also coincided
wi h mos ca ibou de ec ions in he 2012 ae ial su ey (Cuyle e al. 2016).
Aside om a moun ainous coas jus sou h o he ci y o Nuuk, ugged coas al
lowlands (< 200 m ele a ion) p e ail be ween he Ame alik and Se milik
jo ds. Mo ing eas he e ain ises o ele a ions o up o ca. 1000 m and
glacie s become common, speci ically in he middle and sou he n po ions.
Gene ally, ele a ions a e > 300 m.
18
Field me hods
Since 2000, ea ly Ma ch has been he chosen pe iod o ca ibou su eys
because ca ibou dispe sion is high, g oup size is small wi h low a iabili y
and daily mo emen is a he annual minimum (Cuyle e al. 2007, 2011, 2016;
Poole e al. 2013). The o me wo educe a iance among ansec s, diminish
coun ing e o , and maximize p ecision, while he la e lowe s mo emen
be ween o along ansec s. The ae ial su ey pe iod o Ame alik ca ibou
was 08-14 Ma ch 2019. The pla o m o obse a ion was a helicop e AS350.
Pilo moni o ing o helicop e ada al ime e made main enance o a cons an
al i ude possible by cons an ly adjus ing o e ain ea u es while lying low
(40 m, ca. 120 ee ) and slow (ca. 65 km/hou ).
Pa icipan s included h ee obse e s, all wi h p e ious su ey expe ience:
GINR’s senio scien is Ch is ine Cuyle , p o essional hun e Aslak Jensen
(G eenland Associa ion o P o essional Hun e s (KNAPK)) om Nuuk and
Sisimiu hun ing o ice Hans Mølgaa d. Cuyle always sa in on and was
he da a eco de . Cuyle (Obse e 2) ocused on de ec ing ca ibou di ec ly
on ack line (cen e line, 0-line) be o e animals led o line owing o
app oaching helicop e . Jensen and Mølgaa d (Obse e 1 and 3, espec i ely)
we e sea ed in he ea o he helicop e , on ei he side. The side hey sa on
al e na ed each ime he helicop e was e ueled, which was usually once
daily and some imes wice. Jensen and Mølgaa d could no iew he ack line
bu obse ed animals o all dis ances beyond. Ve bal con ac among he
obse e s pe mi ed he digi al audio eco ding o all obse a ions and mos
impo an ly, p e en ed any double coun ing o g oups de ec ed by mo e han
one obse e . Two audio de ices (SONY IC eco de , ICD-SX712) we e used
o eco d sepa a ely he obse a ions speci ic o he le and igh side o he
line ansec . Audio eco ding de ices we e on con inual eco ding o each
line ansec . A he end o each su ey day, audio da a was downloaded o
compu e o s o age and back-up. Obse a ions we e la e pai ed wi h
Global Posi ioning Sys em (GPS) coo dina es o he helicop e a he ime o
obse a ion. Fo each de ec ion, he audio eco ding included dis ance o (see
below) ca ibou g oup, as well as g oup size and beha io and name o he
obse e . G ound su ace and wea he condi ions we e also eco ded. Manual
click-coun e s, logging he numbe o ca ibou seen by an indi idual obse e ,
p o ided low- ech back-up o double-checking he digi al audio obse a ions
o each line ansec .
19
Su ey design
Aligning line ansec s pe pendicula o known g adien s wi hin he su eyed
a ea can maximize p ecision o he esul ing es ima e by lowe ing he
encoun e a e a iance (Buckland e al. 2001). Thus, he ansec axis di ec ion
(eas -wes axis) was chosen as pe pendicula o p e iously known animal
dis ibu ion g adien s in Ma ch and he wes -eas clima e g adien om we
ma i ime o d y con inen al. An ini ial line ansec was compu e gene a ed
a andom in each sub-a ea (see below), and o he s ollowed a 10 o 20 km
apa . The line ansec s lown p o ide he maximum a ea co e age possible
gi en he inancial esou ces a ailable. Because some a p io i ansec s we e
combined du ing su ey, line iden i ica ion numbe s a e no consecu i e.
Figu e 3. The 25 line ansec s used in he 2019 su ey o Sou h Region (no he n po ion), Ame alik
ca ibou popula ion, employing he same h ee colou s as applied o he h ee sub-a eas in abo e igu e
3: Coas al Lowland (o ange, 4 lines), Glacial Moun ains (blue, 3 lines), and Xe ic Inland ( ed, 18
lines). T ansec s sepa a ed by 10 km, excep Glacial Moun ains which we e sepa a ed by 20 km. Line
ansec numbe ing is no consecu i e, as some a p io i lines became amalgama ed du ing su ey.
The su eyed no he n po ion o Sou h egion a ea, 4,676 km2, was di ided
in o h ee sub-a eas, named Coas al Lowland (499 km2), Glacial Moun ains
(1,171 km2), and Xe ic Inland (3,006 km2) (Fig. 2). The sampling design o he
20
2019 su ey conside ed 25 sys ema ic pa allel line ansec s o a iable leng h
placed o e he h ee sub-a eas (Fig. 3). Line ansec s o Coas al Lowland
and Xe ic Inland we e sepa a ed by 10 km and hose o Glacial Moun ains by
20 km. To a oid possible numbe ing con usion wi h he concu en ca ibou
su ey o he Cen al egion, in he Sou h egion line ansec iden i ica ion
numbe s began om 101.
Dis ance o a de ec ed ca ibou g oup (objec -o -in e es ) was be o e ca ibou
mo emen occu ed. Tigh ly cohesi e beha io iden i ied g oups o mul iple
indi iduals. Excep ing g oups on he ack line, which was dis ance 0 m,
dis ance was he obse e ’s ins an aneous and subjec i e es ima e o he
dis ance o cen e o he ca ibou g oup. Exac dis ance measu emen om he
ack line (aka 0-line o cen e line) o a ca ibou g oup was e ec i ely ne e
possible because o p ac ical conside a ions (de ails in Cuyle e al. 2021).
The e o e, like all p e ious helicop e ca ibou su eys in G eenland, o
dis ance measu emen pe pendicula o he ack line, we app oxima ed wi h
ough “dis ance bins”, i.e., in me e s, 0-50, 50-100, 100-200, 200-300, 300-400,
400-500, 500-600, 600-700, 700-800, and 800+. Bin alue eco ded o a g oup
was always he uppe limi o he bin applied. Fo analysis, we did no co ec
o he 40m al i ude o he helicop e . Ins ead, we ecoded he epo ed uppe
dis ance alues o he mid-dis ance o a speci ic bin owing o h ee easons.
Fi s , a ca ibou g oup could be a any dis ance wi hin he bin., e.g., a g oup
eco ded in dis ance bin 300 m, was loca ed somewhe e be ween 200 and 300
me e s. Second, placing a ca ibou g oup wi hin he co ec bin elied hea ily
on obse e abili y o es ima e dis ance o he obse ed animals in ugged
e ain. Thi d, al hough o le el g ound (i sel a e) he es ima ed di ec line
dis ance om obse e (si ing in helicop e a 40 m al i ude abo e g ound) o
a ca ibou g oup would be g ea e han he pe pendicula dis ance om he
ack line o ha g oup, hose di e ences we e small a 100 m and negligible
beyond 200 m (i.e., in me e s 8, 4, 3, 2, 2, 2, 1, and 1). Rega ding he 0-50 m bin,
we assumed obse e abili y su icien o compensa e o 40 m al i ude and
assign a pe pendicula 50 m dis ance co ec ly because immedia ely adjacen
o he helicop e / ack line. Fu he , o aid obse e abili y o es ima e
dis ances, be o e s a ing su ey he helicop e ho e ed a 40m al i ude while
each obse e used a “Leica lase ange inde 1600” o gauge dis ances ac oss
le el ai po g ound o a p io i known pe pendicula dis ances. Then
obse e s ma ked hei window wi h masking ape delinea ing he
app oxima e dis ances o each bin. While on su ey, in he absence o ca ibou
and whe e e ical e ain ea u es occu ed, obse e s used he lase dis ance
21
inde s o es hei abili y o es ima e dis ance, i.e., o he e ain ea u e. On
a e occasions, obse e s we e able o use he lase ange inde s o bin
dis ance o a de ec ed s a iona y g oup.
Once all eco ded dis ances we e ecoded o mid-dis ance, o model he
de ec ion unc ion all he de ec ions we e pooled ac oss obse e s wi h he
helicop e unc ioning as a single obse e . The pooled da a we e used o
es ima e a de ec ion unc ion, hen es ima e he de ec ion p obabili y and
inally o es ima e he densi y o he ca ibou wi hin he su eyed a ea
(Buckland e al. 2001). The de ec ion unc ion, 𝑔(𝑦), desc ibes he p obabili y
o de ec ing an objec -o -in e es gi en ha is a a dis ance 𝑦, om he ack
line, hus being a non-inc easing unc ion o 𝑦 (Buckland e al. 2015). Fo line
ansec s, 𝑦 is he pe pendicula dis ance om he ack line o he de ec ed
objec . Wi hin DS me hods, he p obabili y o de ec ion is explained ecu ing
o hese obse ed dis ances (Buckland e al. 2001).
Dis ance sampling
The ca ibou g oup was he selec ed objec -o -in e es on which de ec abili y
was modelled, i.e., indi idual ca ibou wi hin a g oup we e no conside ed.
The indi idual line ansec s we e he sample uni o design-based
con en ional DS analysis o he 2019 su ey. De ails o how his s udy’s DS
analyses we e pe o med a e in Appendix 3. Thus, es ima ed CVs
(Coe icien s o Va ia ion) om he models a e e e ing o he ansec s, and
o al CV es ima ion is ob ained by di iding he es ima ed s anda d e o by
he espec i e es ima e. The es ima ed s anda d e o is ob ained as a pooled
es ima e o en i e egion and accoun ing o ansec s and hei a iabili y, i
inco po a es he a iance om he de ec ion unc ion (Buckland e al. 2001).
The eco ded dis ances o he obse ed ca ibou g oups we e used o es ima e
a de ec ion unc ion. Wi h his, bo h he ca ibou de ec ion p obabili y and
densi y wi hin he su eyed a ea could be es ima ed (Buckland e al. 2001).
The de ec ion unc ion, 𝑔(𝑦), desc ibes he p obabili y o de ec ing an objec o
in e es (ca ibou g oup) gi en ha i is a a dis ance 𝑦, om he ack line,
hus being a non-inc easing unc ion o 𝑦 (Buckland e al. 2015). Fo line
ansec s, 𝑦 is he pe pendicula dis ance om he ack line o he de ec ed
objec . Wi hin DS me hods, he p obabili y o de ec ion is explained ecu ing
o hese obse ed dis ances (Buckland e al. 2001).

22
P io o DS analysis, he aw da a was i s p ocessed o inconsis encies. Then
ex ensi e explo a o y da a analysis was comple ed, including e alua ion o
obse ed dis ances, be o e p oceeding o de e mining he de ec ion unc ion
h ough model i ing and selec ion (Buckland e al. 2001; Ma ques e al. 2011;
Thomas e al. 2010). To de e mine he de ec ion unc ion, se e al models we e
conside ed, (Thomas e al. 2010). Typically, he model p esen ing he lowes
AIC alue is chosen. De ails ega ding DS heo y, me hods and analysis a e
a ailable in Buckland e al. (2001, 2015), and a b ie e summa y is p o ided in
Appendix 4, wi h a summa y o DS assump ions in Appendix 5. Fo analysis,
we used R S a is ical So wa e (h ps://www. -p ojec .o g/).
Demog aphics
Sex, age, and la e-win e cal ec ui men obse a ions we e ob ained a e
mos o he DS su ey was comple ed. All ca ibou sigh ed we e sexed and
aged ollowing a b ie o e pass wi h he helicop e . Sex and age c i e ia ha e
emained unchanged since 2000 (de ails in Cuyle e al. 2011, 2016). B ie ly,
emale sex was de e mined by he p esence o absence o a ul a and/o
u ine pa ch on he ump o bo h adul s and cal es, i.e., an le size, shape,
p esence, o absence, we e no used o de e mine sex. Two age classes we e
used, cal (age  10-mon hs) and adul (age > 1-yea ). Age was de e mined by
body size. 10-mon h-old cal es, male and emale, being conside ably smalle
han all o he age classes in Ma ch. Cal pe cen age is gi en ela i e o he
o al numbe o ca ibou sexed and aged. Cal ec ui men is alue o la e-
win e and p o ided as he numbe o cal es pe 100 cows. G oup size was
based on p oximi y and g oup cohesion du ing possible ligh esponse. To
ob ain demog aphics and ec ui men alues, on 14 Ma ch, la ge a eas o he
Sou h egion (no he n po ion) we e lown, including he a eas su ounding
line ansec s 107, 109 and 110, he leng h o he Aus mannadalen Valley and
he highlands be ween he e and he own o Kapisilli , he alley leading
om Nauja kûa sou h o Iso ua ssuk Lake and a ound sho es o he la e
and in gene al he moun ains be ween Ame alik Fjo d and Nuuk.
Ele a ions whe e ca ibou de ec ed
Ea ly Ma ch ele a ion use by ca ibou was app oxima ed using GPS da ase
o helicop e ele a ion/posi ion and ma ching imes amps wi h hose o he
digi al audio eco ding o ca ibou obse a ions. GPS and digi al eco de
imes amps we e synch onized be o e su ey began. Be o e analysis, 40 m
23
helicop e al i ude was sub ac ed om all ele a ions. The ea e , and lacking
a eliable cons an co ec ion ac o , nega i e alues we e dele ed.
Na u al mo ali y
In he pas , i locals/hun e s obse ed se e al ca ibou ca casses in he e ain
o on sea ice, his esul ed in ala m abou an assumed nega i e end o he
en i e popula ion. To pu ca cass obse a ions in o pe spec i e, since 2000, all
echnical epo s o G eenland ca ibou su eys ha e included, o ha
speci ic su ey yea , he expec ed numbe o annual adul ca ibou dea hs
esul ing om na u al mo ali y, i.e., no due o ha es . Age dis ibu ions
among ha es ed G eenland ca ibou popula ions ha e sugges ed a na u al
mo ali y o om 8 o 10% pe annum (Loison e al. 2000, Cuyle &
Øs e gaa d 2005). Meanwhile, na u al mo ali y a es om 4 o 8% we e
epo ed o No h Ame ican popula ions wi hou p eda o s (Be ge ud 1967,
1971, Skoog 1968, Kelsall 1968, Hea d & Ouelle 1994), albei hese a e now
conside ed low (Be ge ud e al. 2008) and densi y-independen ac o s, e.g.,
ad e se wea he , can inc ease mo ali y (Ga es e al. 1986). Be ge ud (1980)
p oposed a s anda d adul mo ali y a e o 10% o all No h Ame ican
ca ibou popula ions, and mo e ecen ly Be ge ud e al. (2008) sugges ed 7.7%
o an inc easing popula ion wi h p eda o s. La ge p eda o s a e absen in he
Sou h egion, and inland xe ic condi ions p o ide s able wea he condi ions.
Al hough na u al mo ali y a es a y among yea s (Be ge ud e al. 2008),
gi en he abo e, an assumed s anda d na u al mo ali y a e o 8-10%
(Kingsley & Cuyle 2002) o G eenland ca ibou likely yields a easonable
es ima e o annual mo ali y. This a e is applied o he 2019 abundance
es ima es o p o ide wildli e manage s wi h a ough numbe o expec ed
ca ibou dea hs due o na u al mo ali y wi hin he su ey yea .
Resul s
Su ey logis ics & unp ocessed da a
The ae ial su ey by helicop e o he Ame alik ca ibou popula ion occu ed
wi hin he pe iod 01-14 Ma ch, which pe iod was sha ed wi h he su ey o
he Akia-Manii soq ca ibou popula ion. Poo wea he made h ee days non-
lyable, as did ai po closu es on wo Sundays. DS da a o he Ame alik
ca ibou popula ion was ob ained o e h ee days (08, 09 and 12 Ma ch).
Demog aphics da a was ob ained 14 Ma ch. Typical o AS350 helicop e s
ca ying h ee passenge s and pilo , e ueling was necessa y a e abou 3
hou s o ligh ime, an addi ional 15-20 minu es we e possible when wind
24
condi ions and dis ance o nea es ai po pe mi ed. Helicop e ligh ime
o aled 17 hou s and 03 minu es. Time lown was di ided be ween line
ansec DS su ey (11 hou s; 05 minu es) and he demog aphics su ey (05
hou s; 58 minu es). The 2019 su ey used 25 line ansec s o a o al dis ance
lown o ca. 453 km, i.e., Coas al Lowland 60 km, Glacial Moun ains 48.5 km
and Xe ic Inland 344.5 km (Table 2). Gi en he 453 km o line ansec s lown,
an op imis ic calcula ion o su ey co e age o he Sou h egion’s su eyed
Ame alik a ea (4,676 km2) would be 19-29%, i.e., opog aphy pe mi ing and
assuming maximum s ip wid h o 1000-1500 m o ei he side o he
helicop e . Howe e , o analyses (see DS analysis, page 24), he s ip wid h
was unca ed o 500 m. Thus, co e age a e aged 9.2% o he inal
abundance es ima e. The obse ed aw o als we e 231 ca ibou g oups, which
included 1,123 ca ibou. Mean g oup size was 4.6 ±3.83 ca ibou, and median
g oup size was 4 ca ibou.
Table 2. Summa y o unp ocessed esul s: Su ey o Ame alik ca ibou popula ion by helicop e in he
Sou h egion, 08-12 Ma ch 2019.
Pa ame e
Sou h egion sub-a ea
To al
Coas al
Lowland
Glacial
Moun ains
Xe ic
Inland
Fligh al i ude (m)
40
40
40
40
Fligh speed (km/h )
60-70
60-70
60-70
60-70
Sub-a ea size (km2)
499
1,171
3,006
4,676
Numbe o lines
4
3
18
25
Dis ance lown (km)
59.83
48.51
344.37
452.71
S ip wid h1 (m)
1000-1500
1000-1500
1000-1500
1000-1500
Su eyed a ea ca. (km2)
120 - 179
97 - 145
689 - 1,033
905 - 1,358
Co e age2
24-36 %
8.3-12.4 %
23-34.4 %
19.4-29.0 %
Co e age pos - unca ion3
12.0 %
4.1 %
11.5 %
9.7 %
To al ca ibou obse ed
45
23
1055
1123
# G oups obse ed
5
7
219
231
Mean g oup size
9.0
3.29
4.82
4.6
S d De ia ion g oup size
± 5.24
± 3.04
± 3.64
± 3.83
Median g oup size
8
2
4
4
Maximum g oup size
17
10
23
23
Minimum g oup size
1
1
1
1
1 S ip wid h p o ided is o one side o helicop e only. Mus double o o al s ip wid h.
2 Co e age p io o unca ion o s ip wid h o 500 m.
3 Co e age a e unca ion o he s ip wid h o 500 m o DS analyses (see page 24).
Da a p ocessing
The aw da a se was in Excel o ma con aining he su ey a iables,
including egion, sub-a ea, espec i e a eas (km2), ansec iden i ica ion,
eco ded dis ances, g oup size, and GPS coo dina es. Some imes included
25
wi h ca ibou g oup obse a ions we e ligh cha ac e is ics such as helicop e
side and eloci y, as well as su ey cha ac e is ics such as sola gla e,
isibili y, dead g ound, snow co e ing and dep h, and su ace condi ions
p o iding camou lage backg ounds o he ca ibou. Da a pe aining o habi a
changes we e emo ed because hese conce ned habi a s exclusi ely i.e., he e
we e no ca ibou obse a ions associa ed. The emaining a iables we e
p ope ly es uc u ed wi hin R S a is ical So wa e.
The da a se was subjec o some p io p ocessing be o e analysis. Commen
ields we e dele ed. Va iable names we e ecoded o make hem sensible in R.
All ca ibou obse a ions we e comple e, i.e., none we e missing hei dis ance
o g oup size componen . Thus, no eplacemen s we e necessa y.
Figu e 4. Loca ion and g oup size o ca ibou de ec ions ( unca ed da a) obse ed along he line
ansec s lown, 2019 su ey o Ame alik ca ibou popula ion.
P elimina y analysis dis ance sampling
Fo eliable es ima es o abundance, Buckland e al. (2001) sugges s ha
sample size is a leas 60 o 80 obse a ions and om a minimum o 10 o 20
eplica e line ansec s. The 2019 ca ibou su ey o he Sou h egion me
hese ecommenda ions. Fo example, ega ding obse a ions (de ec ions o
g oups o one o mo e ca ibou), he un unca ed sample size was 231, while
unca ed was 228. Simila ly, he e we e 25 pa allel line ansec s sepa a ed by
32
Table 3. Model compa ison ac oss he h ee Con en ional Dis ance Sampling models and models conside ing di e en co a ia es u he explaining de ec ion.
Key unc ion
Fo mula ( a iable)
𝒙𝟐 p- alue
𝑷
a
se (𝑷
a)
AIC
∆AIC
Haza d- a e
Obse e
0.037
0.350
0.061
685.042
0.000
Haza d- a e
G oup size + Obse e
NA
0.354
0.058
685.178
0.136
Hal -no mal
Obse e
0.061
0.326
0.030
689.524
4.482
Hal -no mal
G oup size + Obse e
0.018
0.326
0.030
691.036
5.994
Hal -no mal
Visibili y
0.656
0.548
0.030
777.210
92.168
Hal -no mal
Helicop e side
0.648
0.550
0.031
777.700
92.658
Hal -no mal
1
0.788
0.554
0.031
778.664
93.622
Uni o m wi h cosine adjus men e m o o de 1
NA
0.746
0.561
0.022
778.888
93.846
Hal -no mal
Camou lage
0.444
0.549
0.031
779.062
94.020
Hal -no mal
Sola gla e
0.446
0.548
0.030
779.062
94.020
Haza d- a e
Boulde s h ough snow
NA
0.582
0.043
779.360
94.318
Hal -no mal
Dead g ound
0.638
0.553
0.031
779.881
94.839
Hal -no mal
G oup size
0.634
0.554
0.031
780.582
95.540
Haza d- a e
Visibili y
0.125
0.603
0.041
781.008
95.966
Uni o m wi h simple polynomial adjus men e ms o o de 2,4
NA
0.521
0.574
0.035
781.171
96.129
Hal -no mal
Vege a ion/G ound h ough snow
0.205
0.548
0.031
781.194
96.152
Haza d- a e wi h simple polynomial adjus men e m o o de 4
1
0.695
0.503
0.073
781.689
96.647
Haza d- a e wi h cosine adjus men e m o o de 2
1
0.556
0.357
0.136
782.076
97.034
Haza d- a e
Helicop e side
0.142
0.576
0.045
782.219
97.177
Haza d- a e wi h He mi e polynomial adjus men e m o o de 4
1
0.521
0.526
0.066
782.268
97.226
Haza d- a e
Sola gla e
0.040
0.605
0.041
782.960
97.918
Haza d- a e
Camou lage
0.048
0.529
0.050
784.079
99.037
Haza d- a e
G oup size
0.129
0.532
0.051
784.344
99.302
Haza d- a e
Dead g ound
0.133
0.567
0.047
784.490
99.447
Haza d- a e
Vege a ion/G ound h ough snow
NA
0.549
0.048
785.649
100.607
Uni o m wi h He mi e polynomial adjus men e ms o o de 2,4
NA
0.0.043
0.664
0.051
786.815
101.773
No e: Fo mula = 1 o no co a ia es. NA is o Uni o m Key. Unde Chi-squa e p- alue: NA = no enough deg ees o eedom o GOF es , (Deg ees o
eedom calcula ed conside ing model pa ame e s, hese a y conside ing which key unc ion used and how many/which explana o y a iables conside ed.)

33
De ec ion unc ion models we e i ed o he unca ed da a, i.e., s ip wid h 𝑤
= 0. 50 km, o each side o he helicop e . Fo hese models, e e y combina ion
o key unc ion and adjus men e ms was es ed (Appendix 7). Addi ional
co a ia es assessed we e Obse e , G oup size, Visibili y, Helicop e side,
Vege a ion and G ound showing h ough he snow su ace, Boulde s showing
h ough he snow su ace, Camou lage, Dead g ound, and Sola Gla e. G oup
size, as co a ia e, did li le o explain ca ibou de ec ion. We did no con e
G oup size in o a ca ego ical a iable (small, medium, la ge) because much
in o ma ion is los o no ad an age, and we can es ima e a p obabili y o
de ec ion o each g oup size when his co a ia e is included in model.
A summa y o he in o ma ion om each model i ed o he da a (Table 3)
p o ides a simple o e iew o he many models, and includes he espec i e
key unc ions, adjus men e ms, model o mula, 𝜒2 Goodness-o -Fi es p-
alue, es ima es o he de ec ion p obabili y, espec i e s anda d e o (se
(𝑃
a)), AIC, and Δ𝐴𝐼𝐶 compa ison be ween each model and he model wi h he
lowes AIC. The bes model i ed o he da a possesses he lowes change in
AIC alue (Δ𝐴𝐼𝐶 = 0).
Fo he 2019 su ey da a om Ame alik ca ibou popula ion, his model has
he haza d a e unc ion as key unc ion, no adjus men e ms added and only
Obse e as co a ia e (AIC = 685.042). Howe e , he models wi h Obse e as
co a ia e had e y poo i s o he ac ual da a (Appendix 7) and poo , o non-
applicable, p- alues. Al hough hose we e he models wi h lowes AIC’s, he
plo s e ealed ha he es ima ed de ec ion unc ions we e nonsense. The nex
unca ed model wi h he lowes AIC was he Hal -no mal wi h Visibili y as
co a ia e. The la ge p- alue o 𝜒2 Goodness o Fi Tes (null hypo hesis is
“ he model i s well o he da a”), means his model i ed he da a well
(de ails page 76 his epo ).
Thus, we chose he model ‘Hal -no mal wi h Visibili y as co a ia e’ (Fig. 14),
which had an es ima ed p obabili y o de ec ion o he Sou h egion o 𝑃
a =
0.548 (se = 0.030, c = 0.055). I is an a e aged es ima e since Visibili y is
included in he model. Consequen ly, each Visibili y le el has i s sepa a e
de ec ion unc ion, co esponding o di e en es ima es o he p obabili y o
de ec ion (Fig. 15). When isibili y was high, p obabili y o de ec ion was
g ea e han when isibili y was medium. Fu he , la ge g oup sizes, e.g.,
g oups ≥ 12 ca ibou, we e only de ec ed when isibili y was high.
34
Figu e 14. His og am o Hal -no mal wi h Visibili y as co a ia e o de ec ed dis ances wi h he
es ima ed de ec ion unc ion o e laid.
Figu e 15. Es ima ed p obabili ies o de ec ion as pe Visibili y (ob ained wi h he i ed model,
unca ed da a).
The es ima es o encoun e a es indica e ha he Xe ic Inland sub-a ea had
he mos ca ibou, since i s es ima e was la ge han he o he sub-a eas (Table
4). Conce ning he design-based es ima es o ca ibou abundance and densi y,
Xe ic Inland is also he sub-a ea p esen ing mo e ca ibou (Tables 5, 6, Fig. 16).
In Ma ch 2019, he Ame alik po ion o he Sou h egion had an es ima ed
popula ion size o 19,503 ca ibou (95% CI: 12,404 – 30,665). Sum o abundance
es ima es o each sub-a ea equals o al es ima ed abundance o he egion.
CV o 0.219 (Table 5, Fig. 16) indica es good accu acy o Ame alik abundance
es ima e. Design-based densi y es ima e o whole su ey egion was 4.17
ca ibou/km2, wi h 95% CI: 2.653 – 6.558 (Table 6, Fig. 16).
35
Table 4. Encoun e a e (ER) es ima es pe sub-a ea (s a um) o ca ibou g oups o he Ame alik
popula ion, conside ing h ee s a a, six bins, and a de ec ion unc ion i ed wi h Visibili y as
co a ia e.
Sub-a ea
Encoun e a e
S anda d E o (se)
Coe icien o Va ia ion (c )
Coas al Lowland
0.155
0.021
0.138
Glacial Moun ains
0.144
0.052
0.362
Xe ic Inland
0.666
0.121
0.182
TOTAL
0.481
0.079
0.164
Table 5. Es ima es o abundance pe sub-a ea (s a um) o he Ame alik ca ibou popula ion in he
Sou h egion, Ma ch 2019, conside ing h ee s a a, six bins and a Hal no mal de ec ion unc ion wi h
Visibili y as a co a ia e.
Sub-a ea
Abundance
Es ima e
S anda d
E o (se)
Coe icien
o Va ia ion (c )
95% Con idence In e al
Lowe
Uppe
Coas al Lowland
1221
340
0.278
74
21,127
Glacial Moun ains
972
528
0.544
114
8,250
Xe ic Inland
17,310
4192
0.242
10,479
28,595
TOTAL
19,503
4268
0.219
12,404
30,665
Table 6. Es ima es o densi y pe sub-a ea (s a um) o he Ame alik ca ibou popula ion in he Sou h
egion, Ma ch 2019, conside ing h ee s a a, six bins and a Hal no mal de ec ion unc ion wi h
Visibili y as a co a ia e.
Sub-a ea
Densi y
Es ima e
S anda d
E o (se)
Coe icien
o Va ia ion (c )
95% Con idence In e al
Lowe
Uppe
Coas al Lowland
2.447
0.680
0.278
0.148
40.335
Glacial Moun ains
0.830
0.451
0.544
0.098
7.045
Xe ic Inland
5.758
1.394
0.242
3.486
9.513
TOTAL
4.171
0.913
0.219
2.653
6.558
Figu e 16. Es ima es o ca ibou densi y (le ) and abundance ( igh ), wi h co esponding con idence
in e als o h ee sub-a eas, Coas al Lowlands, Glacial Moun ains, and Xe ic Inland, and inally o
he Sou h egion (no he n po ion).
36
Ca ibou ligh eac ion o lack he eo
Like he No h egion su ey o 2018 (Cuyle e al. 2021), he Ame alik ca ibou popula ion
su ey o 2019 used digi al audio eco de s o collec obse a ion da a. The digi al
eco de s pe mi ed including in he da ase wha , i any, was he beha io al eac ion o
he ca ibou g oup o he helicop e lying a line ansec pas o o e hem. Beha io could
hen be pu in ela ion o g oup size and dis ance om he line ansec .
Table 7. Mo emen o non-mo emen o ca ibou eac ing o helicop e ly-by, Ma ch 2019. Da ase ha included g oup
size, dis ance om he line ansec , and beha io was n=214.
Pa ame e
Ame alik ca ibou popula ion
Mo emen
Non-Mo emen
p – alue
Numbe o g oups
178
36
% G oup Obse a ions
83.2%
16.8%
GROUP SIZE
Mean g oup size
5.02
4.31
0.341
Con idence Le el (95%)
0.5462
1.4167
S anda d E o
0.2768
0.6979
Median
4
3
Mode
2
2
S anda d de ia ion
3.6929
4.1871
Sample Va iance
13.6379
17.5325
Maximum
20
23
Minimum
1
1
Numbe o ca ibou in ol ed
894
155
DISTANCE 1
Mean dis ance
193.26 m
320.83 m
< 0.0001
Con idence Le el (95%)
20.2487
47.3994
S anda d E o
10.2605
23.3482
Median
200
300
Mode
50
200
S anda d de ia ion
136.8927
140.0893
Sample Va iance
18739.6051
19625.0000
Maximum
800
700
Minimum
50
50
1 Dis ance om he line ansec lown by helicop e .
The e was no signi ican di e ence be ween he size o ca ibou g oups ha exhibi ed
mo emen and hose ha did no , mean 5.0 o mo ing and 4.3 o non-mo ing ( S a = -
0.963; wo- ailed es ing P = 0.341, = 2.012, d = 47). Non-mo ing ca ibou g oups we e ca.
128 m u he away om he line ansec lown by he helicop e han hose ca ibou
g oups showing mo emen (Table 7). The e was a signi ican di e ence be ween he mean
37
dis ance o g oups wi h mo emen , 193.26 m, ela i e o he g oups lacking mo emen ,
320.83 m ( S a = 5.002; wo- ailed es ing P < 0.0001, = 2.010, d = 49).
Ca ibou g oups eac ing o he helicop e ly-by wi h mo emen made up 83.2% o all
obse a ions o which beha io was epo ed. Con e sely, 16.8% o hose g oups
exhibi ed li le o no mo emen . The esul s we e simila when conside ing he absolu e
numbe o ca ibou in ol ed (Table 7). O 1050 indi idual ca ibou o which beha io was
epo ed, 85.2% exhibi ed mo emen while 14.8% o lacked mo emen .
Table 8. De ails o mo emen o non-mo emen o ca ibou eac ing o helicop e ly-by, Ma ch 2019. Da ase o
obse a ions ha included ca ibou g oup size, beha io , and dis ance om line ansec , was n= 214 g oups, which
con ained n = 1,050 indi idual ca ibou.
Ame alik ca ibou popula ion
Ca ego y
G oups
(n = 214)
%
Indi iduals
(n = 1,050)
%
Exhibi ing Mo emen
Running away
137
64.0
700
66.7
Running away high speed
14
6.5
65
6.2
Walking
11
5.1
50
4.8
App oach*
3
1.4
32
3.0
Con used, ci cling igh ly
6
2.8
18
1.7
Running pa allel o line ansec
0
0,0
0
0.0
Running, la e s anding looking
3
1.4
17
1.6
T o ing away
3
1.4
10
1.0
Mixed: some mo ed, o he s did no 1
1
0.5
3
0.3
TOTAL
178
83.2
895
85.2
Lacking Mo emen
S anding s ill
35
16.4
153
14.6
S anding, la e walking
0
0.0
0
0.0
Lying down
0
0.0
0
0.0
Lying down, la e s ood up
1
0.5
2
0.2
Some lying, o he s s anding s ill
0
0.0
0
0.0
Lying down, la e walking
0
0.0
0
0.0
TOTAL
36
16.8
155
14.8
*App oach mo emen (walking, o ing, unning) was owa ds he helicop e while looking a helicop e .
1Mixed = di e en beha io by membe s wi hin same g oup, e.g., some unning owa ds o he s, which s ood s ill and
looked a he helicop e .
Among he 157 ‘ unning’ g oups (Table 8), 151 o hose g oups exhibi ed unaba ed ligh ,
i.e., hey ne e s opped while wi hin iew o he helicop e . G oup composi ion (sex, age)
was de e mined o 101 o hose g oups, o which 88 g oups (87.1%) we e composed o
cows wi h cal es. The e we e 10 adul s only g oups (9.9%) and h ee g oups wi h only
ju eniles (3%).

38
Conside ing only he 47 ca ibou g oups whose o iginal posi ion was on o wi hin 50 m o
he ack line, 42 o hose g oups (91.3%) ne e s opped unning away, h ee g oups we e
con used ci cling igh ly abou (6.5%), and one g oup walked (2.2%). Meanwhile, 1 g oup
lacked mo emen . This was an indi idual cow on he ack line a 930 m ele a ion. The
cow, which possessed bo h an le s, s ood pe ec ly s ill acing he app oaching helicop e
in wha appea ed o be a de ensi e pos u e, e en as we lew o e he .
Demog aphics & ec ui men
Sex, age, and la e-win e cal ec ui men da a we e collec ed in sepa a e speci ic e o
ha was no pa o he line ansec DS da ase . On 14 Ma ch 2019, using jus o e 6 hou s
ligh ime, we sexed and aged 122 g oups o ca ibou, o a o al o 838 animals, in he
Ame alik ca ibou popula ion (Table 9). Cows we e almos 58% o he popula ion, bulls
(age > 1-yea ) ca. 13% and cal es ca. 30%.
Table 9. Demog aphics o Ame alik ca ibou popula ion, Sou h egion, Ma ch 2019.
Pa ame e
Ame alik ca ibou popula ion
Numbe o g oups obse ed
122
GROUP SIZE
Mean
6.87
Con idence In e al (95%)
0.8735
S anda d E o
0.4412
S anda d De ia ion
4.8735
Sample Va iance
23.7512
Median
5
Mode
3
Maximum
25
Minimum
1
DEMOGRAPHIC
O iginal da a
Remo ed 19 o phan cal es
To al indi iduals sexed & aged (n)
838
100 %
819
100 %
Cow (age > 1 yea )
483
57.6 %
483
59.0 %
Cal es om p e ious sp ing
248
29.6 %
229
28.0 %
(140 emales)
16.71 %
-
-
(106 males)
12.65 %
-
-
(2 unknown sex)
0.24 %
-
-
Bull (age > 1 yea )
107
12.8 %
107
13.1 %
(30 adul s, age > 3)
3.6 %
(30 adul s, age > 3)
3.7 %
(77 ju eniles, 1< age < 3)
9.2 %
(77 ju eniles, 1< age < 3)
9.4 %
Rec ui men (cal es / 100 cows)
51.3
47.4
Sex a io (Bull age >3 yea / Cow)
0.06
0.06
Sex a io (Bull age >1 yea / Cow)
0.22
0.22
39
Cal lacking hei dam
Du ing demog aphics da a collec ion a o al o 248 cal es we e obse ed (Table 9), o
which wo we e ‘ ue’ o phan cal es (0.8%), as hey we e in a single cal -only g oup (Table
10) wi h no cows nea by. The emaining 246 cal es (99.2%) we e in g oups (n=96) ha
con ained cows. Howe e , o 11 o hose g oups, cal numbe exceeded he numbe o
cows. In he ex eme, one g oup con ained a single cow accompanied by six cal es. The
i e ‘ex a’ cal es p esen he possibili y o i e o phan cal es. Those 11 g oups con ained
a o al o 65 ca ibou, whose composi ion was 18 cows, 37 cal es, and 10 bulls (ju eniles
and/o adul s occu ed in ou o he 10 g oups). Among hese, wice we obse ed
possible win cal es ollowing one dam/cow, as bo h cal es we e insepa able om he
cow, i.e., bo h clung igh ly o he cow’s heels. In he nine o he g oups ha con ained
mo e cows han cal es. The ‘ex a’ cal (o cal es) was some dis ance om any cow and
he ‘clinging’ cal . This sepa a ion was also e iden du ing g oup ligh away om he
helicop e . The occu ence o wins aside, wi hin hose nine g oups he e we e a possible
17 o phan cal es. Adding he wo cal es in he cal -only g oup (abo e), b ings he o al o
19 o phan cal es. O phan cal es (n=19) we e 7.7% o all cal es obse ed (n=248). No
o phan cal es we e obse ed in bull-only g oups.
I we assume he 19 o phan cal es unlikely o su i e hei i s win e , owing o highe
mo ali y han cal es wi h dams, and he e o e emo e hese om he da ase , hen he
demog aphic becomes he ollowing: cows 59%, bulls 13% and cal es 28%, wi h a educed
cal ec ui men o 47.4 cal es pe 100 cows (Table 9).
G oup composi ion & g oup size
The sex and age composi ion o ca ibou g oups seems o in luence g oup size. G oups
composed o a mix o cows, cal es, and bulls (ju enile o adul ) we e he la ges g oups
obse ed, mean 10.31 ca ibou (Table 10). This mix also had he maximum g oup size o 25
ca ibou. G oups composed o jus cows and cal es had he nex highes mean, 6 ca ibou
and a maximum g oup size o 20 ca ibou. The e we e only wo g oups con aining jus
adul bulls (age > 3-yea s) each wi h h ee bulls. The e we e no g oups con aining jus
ju enile bulls. Ju enile bulls we e always obse ed wi h olde animals, which always
included cows. Thus, he e we e no g oups composed o a mix o ju enile and adul bulls.
The e we e also no g oups o bulls wi h cal es. The e was only one cal (age < 1-yea )
g oup o wo cal es, bo h males.
Ou o he o al 122 g oups sexed, and aged, cow-cal pai s occu ed in 95 o hose g oups,
which in ol ed 751 ca ibou (Table 10). Usually he e we e one o wo cow-cal pai s
40
wi hin a g oup (Fig. 17), wi h he mean numbe o cow-cal pai s pe g oup a 2.38 ±1.74
s anda d de ia ion. A ew g oups we e no able o he la ge numbe o cow-cal pai s.
One g oup o 19 ca ibou was composed o nine cow-cal pai s and one ju enile bull. A
u he h ee g oups included se en cow-cal pai s, in addi ion o he o he animals.
Table 10. G oup size ela i e o g oup composi ion, Ame alik ca ibou popula ion, Sou h egion, Ma ch 2019.
Pa ame e
Ame alik ca ibou popula ion, g oup composi ion
Adul
Bull
Ju enile
Bull
Mixed
Bull1
Bull1
& Cal
Bull1 &
Cow
Bull1, Cow
& Cal
Cow
Cow
& Cal
Cal
Numbe o ca ibou
6
0
0
0
38
433
41
318
2
Numbe o g oups
2
0
0
0
8
42
16
53
1
GROUP SIZE
Mean
3.00
-
-
-
4.75
10.31
2.56
6.00
-
CI (95%)
-
-
-
-
2.18
1.68
0.61
1.00
-
S anda d E o
-
-
-
-
0.92
0.83
0.29
0.50
-
S anda d De ia ion
-
-
-
-
2.60
5.39
1.15
3.65
-
Sample Va iance
-
-
-
-
6.78
29.05
1.33
13.31
-
Median
3
-
-
-
3.5
9.5
2.5
5
2
Mode
3
-
-
-
3
4
3
7
2
Maximum
3
-
-
-
9
25
5
20
2
Minimum
3
-
-
-
2
4
1
2
2
1 Includes bo h ju eniles (1-yea < age < 3-yea ) and adul s (age > 3 yea s).
Figu e 17. Obse ed equency o cow-cal pai s o 95 g oups o which demog aphics in o ma ion was a ailable.
0
5
10
15
20
25
30
35
40
12345679
Numbe o obse a ions
Numbe o Cow-Cal pai s
41
La e-win e an le possession
The demog aphics da ase o he 838 sexed and aged ca ibou (Table 10) included an le
possession o mos obse a ions. Adul (age > 3-yea s) bulls lacked an le s and we e ca.
28% o all males obse ed o age > 1-yea . Ju enile (age 1½-2½-yea s) bulls made up 72%.
In con as o adul bulls, 96.1% o ju eniles possessed an le s om he p e ious au umn,
wo an le s 93.5%: one an le 2.6%), while 3,9% had no isible an le s. Meanwhile, adul
cows possessing one o bo h an le s made up 91.9% o all emales ( wo an le s 79.7%: one
an le 12.2%). Polled (no an le s) cows we e 8.1%. An le possession was no eco ded o
h ee cal es, one emale and wo males. Rega ding emale cal es (n=139), 66.2% possessed
one o bo h an le s ( wo an le s 42.4%: one an le 23.7%), while 33.8% o emale cal es
we e polled. Rega ding male cal es (n=104), 87.5% possessed an le s ( wo an le s 67.3%:
one an le 20.2%), while 12.5% we e polled.
Table 11. App oxima e ele a ions o ca ibou g oups obse ed: DS su ey o he Ame alik ca ibou popula ion by
helicop e in he no he n po ion o Sou h egion, 08-12 Ma ch 2019.
Pa ame e
Sou h egion sub-a ea
To al
Sou h egion
Coas al Lowland
Glacial Moun ains
Xe ic Inland
Sample size
5
7
219
231
ELEVATION
Mean (m)
138
716
656
647
S anda d E o (SE)
86.04
131.65
17.65
17.93
Median
80
620
646
633
Mode
N/A
N/A
898
898
S anda d De ia ion
± 192.4
± 348.3
± 261.1
± 272.6
Va iance
37017.48
121324.67
68193.04
74299.49
Range
465
851
1455
1459
Minimum
12
300
16
12
Maximum
477
1151
1471
1471
Con idence Le el (95%)
238.89
322.14
34.78
35.34
Ele a ions whe e ca ibou de ec ed
All ele a ion esul s o obse ed ca ibou indica e only app oxima e alues (Table 11).
The e we e se e al sou ces o e o on ele a ion alues. The G eenland opog aphy is
moun ainous and ele a ion changes can be ab up , which could place he helicop e a a
adically di e en ele a ion han he ca ibou obse ed. Ma ching he imes amps could
c ea e e o s on ca ibou ele a ion when he digi al eco ding was made be o e o a e he
helicop e passed he ca ibou loca ion. E en ca ibou on he ack line lown did no
necessa ily ecei e co ec GPS posi ions. Owing o ligh beha io , hese ca ibou we e
o en digi ally eco ded while s ill ahead o he helicop e ’s posi ion. Addi ionally, ca ibou
no on he ack line lown could be in e ain a a highe o lowe ele a ion han he
48
mode being 898 m. The ela i ely high ele a ions whe e ca ibou we e obse ed in 2019 is
simila o ele a ion use obse ed du ing he 2012 su ey (mean ele a ion 599 m ±280;
Cuyle e al. 2016). I may only be coincidence, bu bo h su eys we e p eceded by a
win e hun ing season. In 2012, he season ended he day be o e, while in 2019 hun ing
ended 2-weeks p io , i.e., win e 2019 ca ibou hun ing season o he Sou h egion was 01-
15 Feb ua y, wi h a quo a o 100 Ame alik ca ibou (Naalakke suisu 2019).
Explana ions o he ela i ely high ele a ion use in la e win e by he Ame alik ca ibou
would include ha he e a e ela i ely limi ed lowlands in he Sou h egion (Figs. 1, 12)
and mos ca ibou obse ed we e inland, whe e ele a ions a e mos ly >200 m.
Explana ions would also include possible be e o age a ailabili y a highe ele a ions in
his egion. Albei , gi en he la i ude (ca. 64°N), a he 500-800 m ele a ions used by he
Ame alik ca ibou popula ion, a ailable win e o age could be assumed in e io and less
plen i ul han ha ound in lowland alleys (Kö ne 2007). Ano he possibili y would be
ca ibou a e a oiding hun e s p esen a low ele a ions. Snowmobile use may also ha e
in luenced ca ibou choice o ela i ely high ele a ions in win e (Cuyle e al. 2016).
Speci ically, he Sou h egion is eadily accessible by boa and by snowmobile. Use o
snowmobiles is pe mi ed o e much o he Ame alik ca ibou popula ion’s ange,
popula i y o ec ea ional use is inc easing, and he illage o Kapisilli may acili a e
snowmobile access e en o he Xe ic Inland sub-a ea. Elsewhe e, ca ibou a oid a eas o
snowmobile use, becoming displaced om, and e en abandoning, high-quali y habi a
(Simpson 1987, Seip e al. 2007).
The Ame alik ca ibou popula ion used ele a ions ha a e aged ca. 300 m highe han
ele a ions used by he Akia-Manii soq ca ibou popula ion, which we e also su eyed in
Ma ch 2019 (Cuyle e al. 2023). Explana ions would include, mos Ame alik ca ibou we e
in he Xe ic Inland sub-a ea, which lacks ex ensi e lowland a eas. Gi en cu en easy
access o he egion’s lowlands, human dis u bance may also be a con ibu ing ac o o
high ele a ion use by Ame alik ca ibou.
Almos wo decades ago, Ame alik ca ibou made ex ensi e use o he Coas al Lowland
sub-a ea, which is all <200 m ele a ion. Acco ding o Kö ne (2007) lowland habi a
should be highly p e e ed by ca ibou. This supposi ion was con i med in Ma ch 2001,
when 115 ca ibou we e de ec ed on 28 km o lines lown in he Coas al Lowland sub-a ea
(Cuyle e el. 2003). Howe e , he ea e win e hun ing was pe mi ed and he numbe o
ca ibou using he Coas al Lowland sub-a ea dwindled ma kedly. In Ma ch 2006, jus 29
ca ibou we e seen on he same 28 km o lines lown. Fu he , in he same a ea,

49
snowmobiles we e used (illegally) o hun down ca ibou (Cuyle e el. 2007). In Ma ch
2012, placemen o line ansec s changed and only one line ansec ed he Coas al
Lowland sub-a ea. I was 13.5 km in leng h and only se en ca ibou we e seen (Cuyle e
el. 2016). In 2019 he numbe and leng h o line ansec s inc eased. Al hough now 60 km
o lines, we s ill only de ec ed 45 ca ibou. Thus, he obse ed 4.1 ca ibou pe km lown in
2001, d opped 75% o 1 ca ibou/km in 2006 and dec eased u he o 0.5 in 2012 and
emained low, 0.7, o his s udy. La e win e use o he Coas al Lowland sub-a ea by he
Ame alik ca ibou popula ion was high in 2001 and hen d opped. O he han he opening
o win e hun ing season and use o snowmobiles, he e has been no change o he sub-
a ea in he 2001-2019 pe iod, e.g., no unusual la e win e wea he e en s, no new oads o
in as uc u e, e c. This sugges s human dis u bance is he impo an ac o in luencing
la e win e ele a ion use by Ame alik ca ibou in he Sou h egion. While he Akia-
Manii soq ca ibou had al e na e emo e lowland a eas o use (Cuyle e al. 2023) i appea s
high ele a ion was he only op ion a ailable o Ame alik ca ibou a oiding human
dis u bance in lowlands, and speci ically he Coas al Lowland sub-a ea.
La e-win e an le possession
Bulls
As expec ed o ca ibou popula ions, adul (age > 3-yea s) bulls om he Ame alik
popula ion lacked an le s in ea ly Ma ch, while mos , 96%, ju enile bulls e ained one o
bo h hei an le s om he p e ious au umn. Thus, la e-win e an le possession among
bulls age > 1 yea o he Ame alik popula ion is simila o bulls in bo h he Kange lussuaq-
Sisimiu and Akia-Manii soq ca ibou popula ions (Cuyle e al. 2021, 2023). Among la e-
win e male cal es (age < 1-yea ) an le possession a ied o hose same h ee
popula ions. An le possession was common and simila in male cal es o he Ame alik
and Kange lussuaq-Sisimiu popula ions a 87.5% and 86.2%, espec i ely. In con as , in
he Akia-Manii soq popula ion jus 40% o male cal es possessed an le s (Cuyle e al.
2021, 2023).
Cows
Al hough among wild ca ibou popula ions in No h Ame ica, 98% o cows ha e an le s in
la e win e (Kelsall 1968, Reime s 1993, Be ge ud e al. 2008), an le possession among
cows in ca ibou popula ions o Wes G eenland is highly a iable and o en exhibi s a high
pe cen age o polled cows, i.e., no an le s (Thing e al. 1986, Cuyle e al. 2002). In No h
Ame ica, decline in he pe cen age o an le ed cows has been a ibu ed o o e g azed
ange, because ha is a majo ac o causing poo cow body condi ion, which p ecludes
50
an le g ow h (Gaa e & Skogland 1980, Reime s 1983, Thing e al. 1986, Be ge ud e al.
2008). In Wes G eenland, ange condi ion is no he majo ac o in luencing he numbe
o polled cows (Cuyle e al. 2021).
In he Ame alik ca ibou popula ion, 92% o cows had an le s, and mos possessed bo h
an le s (80%) a he han jus one (12%). This was also e lec ed in an le possession o
absence among emale cal es, and o a lesse ex en e en male cal es. The 2019 esul s o
an le possession and absence among Ame alik cows is suppo ed by he 2012 su ey,
which pe cen age o an le ed Ame alik cows was 86% (Cuyle e al. 2016). The g ea e
pe cen age o an le ed cows in 2019 ela i e o 2012, sugges s ha summe /au umn 2018
ange condi ions we e no ad e sely a ec ing an le g ow h among Ame alik cows.
A 92% an le possession, mo e Ame alik cows ha e an le s hen cows om ei he o he
o he wo la ge ca ibou popula ions (Akia-Manii soq and Kange lussuaq-Sisimiu )
su eyed in Wes G eenland. Fo example, in 2019, jus 8% o Ame alik cows we e polled,
which con as s sha ply wi h 68% polled Akia-Manii soq cows (Cuyle e al. 2023) and he
46% polled Kange lussuaq-Sisimiu cows in 2018 (Cuyle e al. 2021). Polled cows a e
common among ca ibou popula ions in Wes G eenland.
Speci ically, he Ame alik ca ibou popula ion has a s ong semi-domes ic eindee (R. .
a andus) he i age (Thing e al. 1986, Jepsen e al. 2002), which s ems om he I i ne a
semi-domes ic eindee he d ha wen e al in his egion du ing he 1970’s (Cuyle 1999).
Since semi-domes ic eindee cows usually ha e an le s in la e win e (Skjennebe g &
Slags old 1968), we suspec he g ea e an le possession among cows o he Ame alik,
ela i e o o he Wes G eenland popula ions, is likely due o his gene ic he i age.
O he species obse ed
Du ing he ea ly Ma ch 2019 su ey species o he han ca ibou we e obse ed. These
included only p a migan, ha es, ox, and e al sheep. The e we e no a ian p eda o s
obse ed. Al hough local knowledge (Cuyle e al. 2016) has epo ed muskox p esence in
he Sou h egion o Wes G eenland, like all p e ious ae ial su eys o his egion, no
muskoxen we e obse ed du ing he ea ly Ma ch 2019 su ey.
The e we e wo ae ial su eys conduc ed in ea ly Ma ch 2019, i.e., his s udy’s Sou h
egion and ano he in he Cen al egion (Cuyle e al. 2023). Al hough he su eys
occu ed almos simul aneously, in he Sou h egion, excep ing e al sheep, he e we e
ewe o each obse ed species (Cuyle e al. 2023).
51
S ill, he Sou h egion’s a ea o su ey e o (Table 2) was 2.4 imes below ha o he
Cen al egion (Cuyle e al. 2023). This pa ially explains he lowe numbe o
obse a ions. Howe e , i emains ha he Sou h egion had ewe p a migan and oxes as
well as no a ian p eda o s. Compa ed o he Cen al egion, la e win e 2019 habi a
condi ions in he Sou h egion appea ed unable o suppo he same abundance o hose
species.
Acknowledgemen s
This p ojec was inanced p ima ily by he Go e nmen o G eenland and by
Pinngo i ale i ik – G eenland Ins i u e o Na u al Resou ces, Nuuk G eenland. G a e ul
hanks go o Ai G eenland Cha e and hei helicop e pilo S ig E ick o his sa e lying.
Fo p o iding expe ienced obse e s, excellen a spo ing ca ibou despi e poo de ec ion
condi ions, hanks a e also due he G eenland Associa ion o P o essional Hun e s
(KNAPK) and he G eenland Fishe ies and License Con ol (GFLK). We also hank Rikke
Guldbo g Hansen and La s Wi ing o cons uc i e e iew o he manusc ip .
52
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Appendix 1
Place names o he Sou h egion
Figu e 22. Place names used ega ding he no he n po ion o he Sou h egion (ca. 63°30’–64°30’°N; 49°–51°40’W),
which is inhabi ed by he Ame alik ca ibou popula ion.
56
Appendix 2
Pho os o c
amou laged ca ibou (and ox)
obse ed Ma ch 2019.
Figu e 23. Six ca ibou, o which i e a e eadily isible. All a e wi hin 75 m o he helicop e . Pho o A. Jensen.
Figu e 24. Six camou laged ca ibou. Some a e isible on a snow pa ch, bu o he s a e di icul o spo when among mix
o hin snow, ba e g ound, and la ligh (lack o shadows). All a e wi hin ca. 100 m o he helicop e . Pho o C. Cuyle .
57
C
amou laged ca ibou
Figu e 25. Se en camou laged ca ibou. None a e eadily isible agains he mix o hin snow, boulde s, and ba e
g ound. All a e wi hin ca. 100 m o he helicop e . Pho o A. Jensen.
Figu e 26. Th ee camou laged ca ibou. Despi e ull sunshine, none a e eadily isible agains he mix o pa chy snow
co e , boulde s, ba e g ound, and willows. All a e wi hin 100-150 m o he helicop e . Pho o C. Cuyle .
64
C
amou laged a c ic ox
Figu e 39. Xe ic inland sub-a ea, illus a ing ege a ion poking h ough hin snow laye . This camou laged one a c ic
ox (blue phase) cu led in a ball in esponse o helicop e a 75-100 m. Pho o C. Cuyle .
Figu e 40. Loca ion o a c ic ox (blue phase) indica ed by blue ci cle. Pho o C. Cuyle .

65
Appendix 3
Fe al sheep (
O is a ies
)
nea Kuussuaq (Aus mannadalen), 14 Ma ch 2019
Figu e 41. One camou laged e al sheep in he o eg ound jus le and below cen e , wi hin 100 m o he helicop e . The
mix o ba e g ound, ocks, and hin snow co e wi h ege a ion poking h ough he snow su ace make de ec ion
di icul . This one e al sheep was associa ed wi h ele en o he s (no in pho o). Pho o C. Cuyle .
Figu e 42. One e al sheep obse ed jus no h o he mou h o he Aus mannadalen alley on willow co e ed peninsula.
I was associa ed wi h ele en o he e al sheep. Pho os A. Jensen.
66
Appendix 4
S a is ical me hods behind Dis ance Sampling
This appendix p esen s he basic building blocks and easoning behind Dis ance Sampling (DS)
me hods, ollowed by some de ails. This summa y o s a is ical me hods is om Co eia (2020).
Fundamen al concep s
Be o e en e ing in o he de ailed heo y behind he DS me hodology, we p esen a simple
design, which is quad a o plo sampling (Buckland e al. 2001; Ma ques,
2009).
In plo sampling, a egion o in e es wi h o al a ea 𝐴, is di ided in o small plo s o a ea
𝑎
𝑝𝑙𝑜𝑡
(Fig. 43). Some o hese small plo s a e andomly chosen o sampling and he o al
numbe o indi iduals wi hin hese, 𝑛𝑝𝑙𝑜𝑡, is eco ded.
Figu e 43. Plo sampling g id example o o al a ea
𝐴
di ided in o smalle plo s o a ea
𝑎
𝑝𝑙𝑜𝑡
.
The densi y wi hin each plo , 𝐷𝑝𝑙𝑜𝑡, is he numbe o indi iduals pe uni a ea o he
espec i e plo so, by de ini ion, i is gi en by
Equa ion (1)
whe e
𝑎
is he o al a ea sampled wi hin
𝐴
. (i.e.,
𝑎 = 4 ⋅ 𝑎
𝑝𝑙𝑜𝑡
= 4𝑘𝑚
2
o Fig. 43)
Since a
andom design was used, he densi y is a ep esen a i e es ima e, by design, o he o al a ea
𝐴
.
Hence,
an
es ima e
o
he
abundance,
𝑁

, can
b
e
ob ained
b
y
simply
mul iplying
𝐷

plo by he
o al
a
ea
𝐴
,
Equa ion
(2)
67
𝑃
The DS me hodology is an ex ension o quad a -based sampling me hods. The de ail ha
c ea es he b idge om one me hodology o he o he is he ac ha he me hod desc ibed
abo e assumes ha e e y indi idual o in e es is de ec ed (Mille e al. 2016). F equen ly, his
assump ion canno be me , speci ically i among he indi iduals o in e es he e a e animals
impossible o obse e owing o low sigh abili y. Se e al ac o s cause low sigh abili y, including
opog aphical ba ie s, wea he condi ions, g ound su ace condi ions and many o he s ela ed
o obse e aining and su ey design. The p opo ion o indi iduals ha we e no de ec ed can
be es ima ed using he de ec ion unc ion i ed o he obse ed dis ances
(Thomas e al. 2002).
Once his p opo ion is es ima ed, i can be conside ed o
ob ain mo e accu a e es ima es
and hen, an ex apola ion o a wide egion can be done
simila ly as shown in Equa ion (2).
In DS, his p opo ion o de ec ed objec s in he a ea 𝑎 is de ined as he p obabili y o
de ec ion, 𝑃𝑎. The e o e, a densi y es ima e can be ob ained as pe Equa ion (1) by adjus ing
𝑛𝑝𝑙𝑜𝑡 by 𝑃𝑎, i.e., by co ec ing he de ec ions o hose ha we e missed. Since he la e
canno be known, in gene al, an es ima e mus be also ob ained, hus
Equa ion
(3)
whe e
𝑃
󰆹
a
is
an
es ima e
o
𝑃
𝑎
ob ained
om
he
dis ance
da a,
and
𝑎
is
he
a ea
o
he
sampled
egion. Usually 𝑎 = 2𝑤𝐿, wi h 𝑤 as he unca ion dis ance, o bo h sides o he
ack line, and he o al ansec leng h
𝐿 = ∑𝑙
𝑗
𝑘
𝑗=1
, whe e 𝑙 is he leng h o ansec 𝑗.
Abundance can be de e mined using a easoning analogous o ha abo e (Equa ion 2). The
unca ion dis ance is de ined as he dis ance beyond which dis ances a e no eco ded.
This
can be de ined in he ield o a he analysis s age.
The coe icien o a ia ion o 𝐷
,
c
𝑣
(𝐷
),
is
ela ed
wi h
w
o
andom
comp
onen
s
e e ed
ab
o
e,
encoun
e
a e
(
𝑛
𝑝𝑙𝑜𝑡
/𝐿
),
and
𝑃
󰆹
a
, plus
a
hi d
one
ha
is
he
es ima e
o
he
exp
ec ed
size o de ec ed clus e s (
𝐸
󰆹
(
𝑠)
).
Assuming
independence
b
e
w
een
hese,
he
o me
is
gi en by
Equa ion
(4)
An app oxima ion o he s anda d e o o 𝐷
,
𝑠𝑒(
𝐷

), is de ined as
Equa ion
(5)
68
Once hese a e ob ained, an app oxima e 100(1 − 𝛼)% con idence in e al (CI) can be
de e mined by
Equa ion
(6)
Whe e is he quan ile o he N(0,1) dis ibu ion 1.96
o a 95% con idence in e al). Howe e , he dis ibu ion o he 𝐷
is posi i ely skewed,
hus an in e al assuming ha 𝐷
 is log-no mally dis ibu ed has be e co e age.
Acco ding wi h Buckland e al. (2015), a 100(1-alpha)% con idence in e al can be gi en by
Equa ion
(7)
whe e
Equa ion
(8)
and
Equa ion
(9)
Fo u he de ails see Buckland e al. (2001) and Buckland e al. (2015).
P obabili y o de ec ion
Gi en he abo e, he p obabili y o de ec ing an objec , gi ing ha i is wi hin he a ea
co
e ed
b
y
he
ansec s,
𝑃

a
,
needs
o
b
e
es ima ed.
F
o
his
p o
jec ,
he
ob
jec
o
in
e es
consis s in ca ibou g oups.
To illus a e he impo ance o his p obabili y, conside ha an obse e walks ac oss a
la ge pa ch o und a and de ec s 8 ca ibou (Fig. 44). While discussing wi h he local biologis ,
and conside ing he biologis ’s expe ience, he/she will s a e ha , on a e age, only one hi d o
all ca ibou p esen a e de ec ed (i.e.
,
𝑃

a
= 1/3) meaning ha p obably he e we e a ound 24
ca ibou wi hin ha pa ch o und a and 16 ha e been missed. Tha is whe e DS is use ul, since
i allows a igo ous amewo k o he es ima ion o
P
a and hen an es ima e o abundance can
be ob ained as shown in Equa ion (3).
69
Figu e 44.
Example o a pa ch o und a wi h he ansec in he middle. Blue do s ep esen eigh obse ed ca ibou, while
o ange do s ep esen he 16 unde ec ed ones. The lines pe pendicula
o he ansec ep esen he eco ded dis ances.
Dis ance Sampling me hods
The de ec ion unc ion, 𝑔(𝑦), desc ibes he p obabili y o de ec ing an objec o in e es
gi en ha i is a a dis ance 𝑦, om he ack line (also known as 0-line), hus being a non-
inc easing unc ion o 𝑦 (Buckland e al. 2015).
Fo line ansec s, 𝑦 is he pe pendicula dis ance om he 0-line o he de ec ed objec .
Wi hin DS me hods, he p obabili y o de ec ion is explained ecu ing o
hese obse ed
dis ances (Buckland e al. 2001). Some imes co a ia es may be added o explain hei
ela ionship wi h he de ec ion p obabili y. In his si ua ion, we a e wi hin he Mul iple
Co a ia e Dis ance Sampling (MCDS) amewo k (Buckland e al. 2001).
Con en ional Dis ance Sampling
Con en ional Dis ance Sampling (CDS) occu s when no addi ional co a ia es a e added o
he
mo
del.
Once
he
de ec ion
unc ion
is
es ima ed,
𝑃

a can
b
e
ob ained
ia
he
ollo
wing
equa ion
Equa ion (10)
whe e 𝜋(𝑦)= 1
𝜔 and, he e o e, used o es ima e densi y using Equa ion (3). Fo 𝑔(𝑦) i is
also speci ied a lexible semi-pa ame ic model, composed by a key unc ion and some

70
addi ional se ies expansions, known as adjus men e ms, and hei pa ame e s a e
es ima ed (Ma ques e al. 2007).
To ob ain obus es ima es o densi y, lexible models o
𝑔(𝑦)
a e needed wi h he
o m
(Buckland e al. 2001)
Equa ion (11)
whe e
𝑘(𝑦)
is he pa ame ic key unc ion and
𝑠(𝑦)
ep esen s he addi ional adjus men
e ms (Table 12).
Table 12.
Commonly used key unc ions and se ies expansions o he de ec ion unc ion. Adap ed om
Buckland (2001).
The uni o m key unc ion has no pa ame e s, while he hal -no mal and he haza d- a e
unc ions include a scale pa ame e , 𝜎, which de e mines he a e a which he unc ion
dec eases wi h inc easing dis ance (Fig. 45). Fu he mo e, he haza d- a e unc ion also
includes a shape pa ame e ,
𝑏
, ha p o ides g ea e lexibili y o his unc ion compa ing o
he
o he s (Buckland e al. 2001).
I is no always necessa y o include adjus men e ms, and, in such cases, hese models a e
e e ed o as “key only” models. When he key unc ions a e no enough o i ing
𝑔(𝑦)
, some
se ies expansions e ms may be added o modi y i s shape (Fig. 46). These e ms
can be
ei he cosine, simple polynomial o He mi e polynomial (Table 12).
I is impo an o no e ha hese adjus men e ms do no depend di ec ly on 𝑦 bu on 𝑦𝑠
which is a scaled alue o
𝑦
, whe e
𝑦
𝑠
=
𝑦
𝜔
wi h
𝜔
being he unca ion dis ance. This allows
independence be ween he shape o he se ies expansion and he uni s used o
𝑦
(Ma ques
e al. 2007).
71
Figu e 45. Hal -no mal ( op ow) and haza d- a e (bo om ow) de ec ion unc ions wi hou adjus men s, a ying scale (σ) and, only o haza d- a e, shape (b)
pa ame e s. Values es ed a e p esen ed abo e he plo s. On he op ow om le o igh , he s udy species becomes mo e de ec able (highe p obabili y o
de ec ion a la ge dis ances). The bo om ows show he haza d- a e model’s mo e p onounced shoulde . Adap ed om Buckland e al. (2001).
72
Figu e 46. Possible shapes o he de ec ion unc ion when cosine adjus men s a e included o hal -no mal and haza d- a e models. Adap ed om Buckland e al. (2001).
73
Righ unca ion o he da a, o he emo al o he la ges dis ances, is a common p ocedu e
ha aids model i ing. Some p ecision migh be los wi h unca ion; howe e , i is usually
sligh . On he o he hand, p ecision is inc eased since he da a is easie o model and,
consequen ly, ewe pa ame e s and adjus men e ms a e equi ed o model he de ec ion
unc ion (Cou u ie e al. 2018).
Mul iple Co a ia e Dis ance Sampling
CDS me hods can be ex ended o MCDS, so ha
𝑔(𝑦)
is modelled as a unc ion no only o
dis ance, bu also o a ec o o
𝐽
addi ional co a ia es o each o he 𝑛 objec s o in e es ,
z
i
=
z
𝑖1
, ...,
z
𝑖𝐽
,
𝑖 = 1, ..., 𝑛
. Acco dingly, he unc ion ha
desc ibes
he
p obabili y
o de ec ion
a a gi en dis ance, is ep esen ed by
𝑔(𝑦,
z
)
. These
addi ional
co a ia es
can ei he be disc e e
o con inuous, such as obse e and g oup size, and a e assumed o a ec
only he scale, 𝜎, o
he de ec ion unc ion (Ma ques e al. 2007; Mille e al. 2016). Fo
line ansec s,
𝑃 (
z
i)
, i.e.,
he p obabili y o de ec ing he
𝑖
- h objec o in e es gi en i s espec i e ec o o
co a ia es
z
i
can be es ima ed using he o mula p esen ed in Equa ion
(12).
Equa ion (12)
wi h 𝜋(𝑦)= 1
𝜔. Conside ing he h ee key unc ions p e iously p esen ed, only he
uni o m key is excluded om MCDS since i does no ha e a scale pa ame e . Hal -no mal
and haza d- a e unc ions can ha e hei scale pa ame e w i en as a unc ion o he
co a ia e alues as
Equa ion (13)
Whe e 𝛽0and all he 𝛽𝑗’s a e he J + 1 coe icien s o be es ima ed wi h J being he o al
numbe o co a ia es. The es ima ion o he pa ame e s o bo h CDS and MCDS is
ypically done ia maximum likelihood (Ma ques e al. 2007).
Once he de ec ion unc ion is es ima ed, acco ding wi h (Buckland e al. 2004), densi y can
be es ima ed as
Equa ion (14)
whe e
𝑎
is
he
o al
a ea
su ey
ed,
𝑃
(
z
i
)
is
he
es ima ed
p obabili
y
o
de ec ing
he
𝑖
- h
objec o in e es gi en i s espec i e ec o o co a ia es zi.
80
Appendix 6
Pho os, Sou h egion ae ial su ey condi ions o census o he
Ame alik ca ibou popula ion, Ma ch 2019
Figu e 48. Coas al Lowlands sub-a ea in backg ound beyond he mou h o Bukse jo d, which c osses
he middle o his pho o, iew is sou h. Line ansec 125 pa allels Buskse jo d. Pho o C. Cuyle .
Figu e 49. Coas al Lowlands sub-a ea, iew eas owa ds bo de ing moun ains. Pho o A. Jensen.
Figu e 50. Coas al Lowlands sub-a ea, wes end line ansec 127, iew is no h. Pho o C. Cuyle .

81
Sou h egion ae ial su ey condi ions, Ma ch 2019
Figu e 51. Glacial Moun ains sub-a ea, I oqqa miu Kange lua sunngua (Bukse jo d) and Hyd o
Powe s a ion loca ed a he bo om o jo d. Line ansec 121 was lown o e he a ea le o cen e ,
iew is sou hwes . Pho o A. Jensen.
Figu e 52. Glacial Moun ains sub-a ea, sou h o line ansec 122 and wes o 117, illus a ing he
moun ains and glacie s ypical o his sub-a ea, iew is sou hwes . Pho o A. Jensen.
82
Sou h egion ae ial su ey condi ions, Ma ch 2019
Figu e 53. Glacial Moun ains sub-a ea, middle po ion o line ansec 123, iew is no heas up he
lake, Sangujaa Tase sua . Pho o A. Jensen.
Figu e 54. Glacial Moun ains sub-a ea, i e alley, Qoo usussuaq, which is jus eas o line ansec
123, iew is no h. Pho o A. Jensen.
83
Sou h egion ae ial su ey condi ions, Ma ch 2019
Figu e 55. Glacial Moun ains sub-a ea, eas end o line ansec 123, illus a ing one o se e al glacie s
in his sub-a ea, iew is sou h. Pho o A. Jensen.
Figu e 56. Glacial Moun ains sub-a ea, he alley and lake, Eqalui , an a ea a ypical amongs he
moun ains and glacie s common o his sub-a ea, iew is sou hwes . Pho o A. Jensen.
84
Sou h egion ae ial su ey condi ions, Ma ch 2019
Figu e 57. Xe ic inland sub-a ea, line ansec 101, iew eas , no e hin snow laye . Pho o C. Cuyle .
Figu e 58. Xe ic inland sub-a ea, line ansec 102, iew wes , no e hin snow laye . Pho o C. Cuyle .
85
Sou h egion ae ial su ey condi ions, Ma ch 2019
Figu e 59. Xe ic Inland sub-a ea, app oaching eas end line ansec 103, iew eas . Pho o C. Cuyle .
Figu e 60. Xe ic Inland sub-a ea, eas end line ansec 103, iew no h. Pho o C. Cuyle .

86
Sou h egion ae ial su ey condi ions, Ma ch 2019
Figu e 61. Xe ic inland sub-a ea, line ansec 104, sou h o Kapisilli , iew is sou h. Pho o C. Cuyle .
Figu e 62. Xe ic Inland sub-a ea, iew no h illus a ing mou h o b oad b aided i e alley,
Sa qa ssuaq, which is sandwiched be ween Akulle suaq o he no h (backg ound) and Nuna a ssuaq
o he sou h ( o eg ound), Kange suneq jo d a le . Line ansec 105 an om inne b aided i e
along a moun ainside o Akulle suaq and ou o he sho es o Kange suneq. Pho os C. Cuyle .
87
Sou h egion ae ial su ey condi ions, Ma ch 2019
Figu e 63. Xe ic Inland sub-a ea, eas end o line ansec 106, iew wes ac oss Akulle suaq. No e he
amoun o ba e g ound wi h no snow laye . Pho o A Jensen.
Figu e 64. Xe ic Inland sub-a ea, line ansec 107, iew eas , no e hin snow laye and p esence o 16
ca ibou. Pho o C. Cuyle .
88
Sou h egion ae ial su ey condi ions, Ma ch 2019
Figu e 65. Xe ic Inland sub-a ea, iew no heas o e Nuna aa suk and a ea o line ansec 108,
Akulle suup Se mia a le . No e, hin snow pe mi s g ound o show h ough. Pho o C. Cuyle .
Figu e 66. Xe ic Inland sub-a ea, line ansec 108, Nuna aa suk, iew eas . No e, hin laye o snow
pe mi s g ound o show h ough i . Pho o C. Cuyle .
89
Sou h egion ae ial su ey condi ions, Ma ch 2019
Figu e 67. Xe ic Inland sub-a ea, a ound he wes end o line ansec 110, ou ca ibou, iew NNE.
The e is a mix u e o almos ba e g ound and windblown snow o a ying dep h. Pho o A. Jensen.
Figu e 68. Xe ic Inland sub-a ea, a ound he eas end o line ansec 110, wo g oups o ca ibou, ou
(uppe le ) and wo (bo om igh ), iew eas . The snow laye is gene ally hin, al hough hicke
pa ches occu whe e snow has been windblown in o d i s. Pho o A. Jensen.
96
Sou h egion ae ial su ey condi ions, Ma ch 2019
Figu e 80. Xe ic inland sub-a ea, eas end line ansec 119 a sho e o lake, Ilulialik, iew is no heas
om sou hwes end o he lake. Pho o A. Jensen.
Figu e 81. Xe ic inland sub-a ea, iew o SW end o he lake, Ilulialik and he eas end poin o line
ansec 119 a lakesho e. Line ansec 119 came down o he highlands o he igh . Pho o A. Jensen.

97
Appendix 7
His og ams o de ec ed dis ances
His og ams o de ec ed dis ances supe imposed wi h es ima ed de ec ion
unc ions o all unca ed i ed models, p esen ed o de as in Table 3
98
99
Figu e 82. His og ams o de ec ed dis ances supe imposed wi h es ima ed de ec ion unc ions o all
unca ed i ed models.
The pa ame e es ima es and a iabili y associa ed wi h hem (Table 13),
essen ially illus a es ha he "Medium" isibili y has a lowe de ec ion
p obabili y es ima e han he "High" isibili y (as also shown in Fig. 15).
Table 13. De ec ion unc ion pa ame e s’ es ima es.
Es ima e
S anda d E o
In e cep
-1.444
0.074
Visibili y Medium
-0.378
0.156
No e: Es ima es a e on log scale.
100
Appendix 8
Glacie bounded lakes ha ecen ly emp ied, Ma ch 2019
While lying he 2019 ae ial su eys (Cen al and Sou h egions), we obse ed
ou lakes ha had emp ied ecen ly (Figs. 83-87). All had connec ions o he
G eenland Ice Cap o o glacial ongues. Likely mo e such lakes exis bu we e
no de ec ed because obse a ions we e limi ed o he ap io i line ansec s
lown.
Figu e 83. Loca ions o he ou lakes obse ed o ha e ecen ly emp ied, be o e Ma ch 2019.
101
Glacie bounded lakes ha ecen ly emp ied, Ma ch 2019
Figu e 84. Small lake in Cen al egion, Uja assui sub-a ea, ha ecen ly emp ied in wha appea s o
ha e been an all-a -once e en , e.g., su ace lake ice emains s ewn on moun ainside. Highwa e line is
indica ed by hin ice- oo ( igh o cen e ) unning along moun ainside. A p e ious highwa e ma k is
sugges ed by he ligh -g ey ba e ock abo e he ecen highwa e ice- oo . This lake bo de s he no h
side o Na sap Se mia (Na sap Glacie ), and line ansec 27. (Fig. 83, Numbe 1). Pho o C. Cuyle .
Figu e 85. Emp ied la ge lake in Sou h egion, Xe ic Inland sub-a ea, illus a ing ma ked highwa e
line on moun ainside. Lake size and heigh o highwa e line compa ed o cu en ele a ion o lake
su ace sugges s an eno mous wa e olume was in ol ed in he emp ying e en , which may ha e been
p io o eeze up win e 2018/2019, since he e is no isible dis u bance o su ace ice along he lake
sho e. This lake bo de s he sou h side o he Na sap Se mia (Na sap Glacie ), and line ansec 101.
(Fig. 83, Numbe 2). Pho o C. Cuyle .

102
Glacie bounded lakes ha ecen ly emp ied, Ma ch 2019
Figu e 86. Recen ly emp ied pond, Aus mann je n, nea eas end o line ansec 112, a G eenland Ice
Cap, Xe ic Inland sub-a ea, Sou h egion. Google Ea h P o image ( aken 2014) shows Aus mann je n
much enla ged, while by Ma ch 2019 i had emp ied. S ewn placemen o ice chunks sugges s
emp ying occu ed pos summe 2018 and all-a -once. Abo e iew is o he no h, below is o
no hwes . (Fig. 83, Numbe 3). Pho os C. Cuyle .
103
Glacie bounded lakes ha ecen ly emp ied, Ma ch 2019
Figu e 87. La ge unnamed lake in Sou h egion, Xe ic Inland sub-a ea, on he no h side o line
ansec 117. This lake bo de s he no h side o a G eenland Ice Cap glacial ongue The e we e a leas
i e highwa e lines on he black moun ainside ( igh side o bo om pho o). This sugges s he lake has
emp ied o i s p esen su ace le el in i e s ages. While he iming o hose e en s is unknown, he
mos ecen may ha e been p io o eeze up win e 2018/2019, since he e is no isible dis u bance o
su ace ice along he lake sho e. P e ious lake su ace ele a ion om s anda d maps was 710 m.
Emp ying wa e would pass h ough he lake, Iso ua suup Tasia. The Alanngo lia jo d is known o
ab up ises in sea le el owing o lake emp ying. (Fig. 83, Numbe 4). Pho o A. Jensen.
104
Appendix 9
Recommenda ions o imp o ing u u e su eys
Ae ial su ey me hods & design
The 9.7% su ey co e age o he 2019 Dis ance Sampling (DS) su ey o he
Ame alik ca ibou popula ion, p omo es accu acy o abundance es ima es and
should be main ained o imp o ed in he u u e o pe mi e alua ing
popula ion ends. When lying line ansec s, dis ance and o he ac o s o en
make iden i ica ion o cal es impossible, esul ing in an unde es ima e o cal
numbe . Demog aphic (sex, age, cal ec ui men ) da a mus con inue o be
collec ed in e o s sepa a e om lying he line ansec s o DS.
Fligh al i udes om 30 o 40 m pe mi scanning he landscape o ca ibou
e en ou o 1000-1500m om he ack line wi hou dead-g ound in e e ing.
Jus be awa e he deg ee o which he ca ibou a e ex emely camou laged
agains he ypical backg ounds. This can cause obse e a igue, men al
exhaus ion, e en a he ela i ely slow speeds lown (60-70 km/hou ). Any
‘dead’ g ound causing ca ibou de ec ions o be missed, will likely be
mi iga ed by he DS analysis.
T aining and es ing, obse e abili y o judge co ec dis ance bin is necessa y
o imp o emen o his impo an a iable. I is he au ho ’s expe ience ha
wi hou p ac ice people commonly misjudge dis ance. Looking down om
abo e can exace ba e his endency. Fla e ain may p o ide a mo e (no mal)
ho izon al line-o -sigh o he animals, which may inc ease binning accu acy.
Howe e , e ain ha slopes away, ei he up o down, con uses obse e s’
abili y o judge dis ance om ack line o animals. The s eepe he slope, he
g ea e he e o s.
The iming o ae ial su eys could emain ea ly Ma ch because ha coincides
wi h annual minimum ca ibou mo emen (a oids double coun ing), and
enough day leng h o lying he pilo maximum o 7-hou s pe day.
Expe ience om eigh su eys since 2000 has illus a ed ha snow co e and
dep h is a iable ega dless o he win e pe iod chosen.
In G eenland, helicop e s a e seldom a ailable a sho no ice. Book abou 3-5
mon hs ahead and ea i m booking se e al imes he ea e . Fo es ima ing
he necessa y window (da es) ha helicop e is booked o su ey, i s
calcula e he numbe o days equi ed o su ey. Then, add days o allow o
105
se e al non- lying days owing o pilo lying hou s going o e weekly limi ,
ai po closu es on Sundays, and poo wea he . Fo he la e a minimum 3-4
days should be alloca ed.
Book su ey obse e s ea ly (Fig. 88), abou six mon hs in ad ance, o ensu e
he p obabili y o ob aining he obse e s you equi e. A ibu es would
include p e ious expe ience de ec ing supe bly camou laged ca ibou, and
p o en lack o nausea, e.g., on ships a sea o in helicop e s. E en he usually
seda e helicop e maneu e s o line ansec s can illici nausea in some.
Meanwhile, he non-s op ab up lying maneu e s equi ed o ob ain ca ibou
demog aphics cause nausea in mos pe sons.
No e: P e ious helicop e expe ience, including animal li e cap u e, does no
gua an ee lack o nausea du ing sha p he maneu e s speci ic o ca ibou
demog aphics wo k.
Figu e 88. The h ee obse e s, D . Ch is ine Cuyle , scien i ic leade (le ), Aslak Jensen, comme cial
hun e (cen e ), and Hans Mølgaa d, Sisimiu hun ing o ice ( igh ).
S anda diza ion o da a collec ion ega ding su ace condi ions
P io o 2019, he co a ia es (including deg ee o camou lage, % snow co e ,
snow dep h, icing, isibili y, ligh ing (e.g., la ligh , shadow), p esence o
boulde s and hei size, ege a ion poking h ough snow laye s, e c.) we e
eco ded wi hou s anda diza ion and o en ad hoc. In con as he 2019
su ey used speci ic s anda dized quali a i e e ms o make he co a ia es
a ailable o analyses. E alua ions o all en i onmen al co a ia es we e
s anda dized o jus i e easy quali a i e e ms: Ze o, Low, Medium, High,
and Ex eme. Howe e , he e we e oo many co a ia es o pe mi eco ding
each wi h e e y de ec ion o he objec -o -in e es (ca ibou).
I he co a ia es a e o be use ul in analyses, an e alua ion mus be assigned
o mos ca ibou de ec ions, ideally o all. Howe e , his is usually