Highe mobili y o bu e lies han mo hs connec ed o
habi a sui abili y and body size in a elease expe imen
Mikko Kuussaa i
1
, Ma ias Saa inen
2
, Ee a-Liisa Ko pela
1
, Juha P€
oy y
1
& Te ho Hy €
onen
3
1
Finnish En i onmen Ins i u e, Na u al En i onmen Cen e, P.O. Box 140, FI-00251 Helsinki, Finland
2
Cas 
eninka u 10 b 17, FI-00530 Helsinki, Finland
3
MTT Ag i ood Resea ch Finland, Plan P oduc ion Resea ch, FI-31600 Jokioinen, Finland
Keywo ds
Animal mo emen , dispe sal p opensi y,
expe imen al s udy on mig a ion, habi a
p e e ence, in e speci ic di e ences in
mobili y, ma k- elease- ecap u e s udy,
elease habi a sui abili y, species ai s,
a ia ion in dispe sal abili y, wingspan.
Co espondence
Mikko Kuussaa i, Finnish En i onmen
Ins i u e, Na u al En i onmen Cen e, P.O.
Box 140, FI-00251 Helsinki, Finland.
Tel: +358 40 5256 249,
Fax: +358 20 490 2290;
E-mail: [email p o ec ed]
Funding In o ma ion
This s udy was unded by he Finnish Minis y
o Ag icul u e and Fo es y ia he
ECONTOOLS p ojec and by he Maj and To
Nessling Founda ion.
Recei ed: 13 Ma ch 2014; Re ised: 1 July
2014; Accep ed: 13 July 2014
Ecology and E olu ion 2014; 4(19): 3800–
3811
doi: 10.1002/ece3.1187
Abs ac
Mobili y is a key ac o de e mining lepidop e an species esponses o en i on-
men al change. Howe e , di ec mul ispecies compa isons o mobili y a e a e
and empi ical compa isons be ween bu e lies and mo hs ha e no been p e i-
ously conduc ed. He e, we compa ed mobili y be ween bu e lies and diu nal
mo hs and s udied species ai s a ec ing bu e ly mobili y. We expe imen ally
ma ked and eleased 2011 bu e ly and 2367 mo h indi iduals belonging o 32
and 28 species, espec i ely, in a 25 m 925 m elease a ea wi hin an 11-ha, 8-
yea -old se -aside ield. Dis ance mo ed and emig a ion a e om he elease
habi a we e eco ded by species. The elease expe imen p oduced di ec ly
compa able mobili y da a in 18 bu e ly and 9 mo h species wi h almos 500
indi iduals ecap u ed. Bu e lies we e ound mo e mobile han geome oid
mo hs in e ms o bo h dis ance mo ed (mean 315 m s. 63 m, espec i ely)
and emig a ion a e (mean 54% s. 17%, espec i ely). Release habi a sui abil-
i y had a s ong e ec on emig a ion a e and dis ance mo ed, because bu e -
lies ended o lea e he se -aside, i i was no sui able o b eeding. In
addi ion, emig a ion a e and dis ance mo ed inc eased signi ican ly wi h
inc easing body size. When phylogene ic ela edness among species was
included in he analyses, he signi ican e ec o body size disappea ed, bu
habi a sui abili y emained signi ican o dis ance mo ed. The highe mobili y
o bu e lies han geome oid mo hs can la gely be explained by mo phological
di e ences, as bu e lies a e mo e obus lie s. The impo an ole o elease
habi a sui abili y in bu e ly mobili y was expec ed, bu seems no o ha e
been empi ically documen ed be o e. The obse ed posi i e co ela ion be ween
bu e ly size and mobili y is in ag eemen wi h ou p e ious indings on bu -
e ly coloniza ion speed in a long- e m se -aside expe imen and ecen me a-
analyses on bu e ly mobili y.
In oduc ion
Dispe sal abili y is a key ac o a ec ing occu ence pa -
e ns and popula ion ends in animals (Ewe s and Did-
ham 2006). Ongoing changes in land use and clima e also
pose s ong selec i e p essu es on species ai s ha a e
connec ed o animal mobili y (Bon e e al. 2012; Bague e
e al. 2013). An inc eased need o unde s and he impac s
o en i onmen al change a popula ion and communi y
le els has ecen ly a ac ed much in e es in he
measu emen o mobili y di e ences ac oss indi iduals,
popula ions, and species (Bowle and Ben on 2005; Clo-
be e al. 2012). Howe e , despi e he accumula ing
expe ience in es ima ing mobili y (Na han e al. 2008),
p oducing eliable mul ispecies compa isons has emained
a challenging ask. He e, we used bu e lies and mo hs
o a mul ispecies mobili y compa ison o examine di e -
ences in dispe sal abili y among species and be ween spe-
cies g oups. Bu e lies a e one o he mos popula
g oups in animal mobili y esea ch (S e ens e al. 2010),
whe eas knowledge on o he insec g oups, e en among
Lepidop e a, has emained scan y.
3800 ª2014 The Au ho s. Ecology and E olu ion published by John Wiley & Sons L d.
This is an open access a icle unde he e ms o he C ea i e Commons A ibu ion License, which pe mi s use,
dis ibu ion and ep oduc ion in any medium, p o ided he o iginal wo k is p ope ly ci ed.
Se e al p e ious s udies on bu e lies ha e demon-
s a ed he impo an ole o in e speci ic mobili y di e -
ences in species dis ibu ions and species esponses o
habi a and clima e change. Fo example, he e ec s o
habi a agmen a ion ha e been shown o di e be ween
bu e ly species wi h a ying mobili y (
€
Ockinge e al.
2009, 2010).
€
Ockinge e al. (2010), using body size as a
p oxy o mobili y, showed ha bu e ly species wi h low
mobili y ha e been mos s ongly a ec ed by habi a loss
and o he s udies ha e epo ed simila esul s. Ko iaho
e al. (2005) ound ha h ea ened bu e ly species a e
cha ac e ized by low mobili y, and he me a-analysis by
Thomas e al. (2011) showed ha dispe sal abili y is one
o he main d i e s o long- e m bu e ly popula ion
ends. These esul s indica e ha dispe sal abili y may
c ucially a ec how species can cope wi h global h ea s
such as clima e change and habi a loss and agmen a ion.
Mo eo e , ecen s udies ha e highligh ed he impo -
ance o in aspeci ic a ia ion in mobili y and ha ela-
i ely as mic oe olu iona y changes in dispe sal abili y
and emig a ion p opensi y may play a signi ican ole
when species a e adap ing o changing en i onmen s
(Me ckx e al. 2003; Sch ickzelle e al. 2006; Duplouy
e al. 2013). Fas e olu iona y changes may in luence eco-
logical popula ion dynamics and ice e sa, po en ially
causing complex eco-e olu iona y dynamics in dispe sal
(Hanski and Mononen 2011). Howe e , he la ge numbe
o ac o s in luencing e olu ion o dispe sal complica es
p edic ions on wha would be he op imal dispe sal s a -
egy in di e en landscapes and in case o di e en popu-
la ion s uc u es (Clobe e al. 2012).
Bu e ly mobili y has been empi ically s udied using a
numbe o di e en app oaches (S e ens e al. 2010; Seka
2012). The mos popula app oach has been o conduc
ma k- elease- ecap u e (MRR) s udies in na u al bu e ly
(me a)popula ions (Ho es ad and Nieminen 2009). How-
e e , mobili y es ima es om di e en single-species MRR
s udies a e no di ec ly compa able, because he esul s a e
s ongly dependen on he spa ial scale (Schneide 2003;
F anz
en and Nilsson 2007) and landscape s uc u e
(Mennechez e al. 2003; Do e and Se ele 2009) o di e -
en s udies. Manipula i e expe imen al app oaches ha e
enabled o answe mo e speci ied ques ions conce ning
di e en componen s o bu e ly mobili y and o ca y
ou in a- and in e speci ic compa isons. Howe e , expe i-
men al eleases o bu e lies in he ield (S€
ode s €
om and
Hedblom 2007; Kallioniemi e al. 2014) and s udies con-
duc ed in la ge habi a cages (No be g e al. 2002; Hanski
e al. 2006) ha e been ela i ely es ic ed in spa ial scale
and ha e a ely in ol ed mo e han wo species.
Because o he g ea demand o compa able mobili y
es ima es in communi y ecological s udies, he e is an
ob ious need o empi ical s udies p oducing compa able
mobili y es ima es o a la ge numbe o species simul a-
neously and in s anda dized condi ions. We p oduced
such es ima es by expe imen ally eleasing a la ge numbe
o ma ked indi iduals o 60 bu e ly and diu nal mo h
species in a la ge se -aside ield and hen collec ing ecap-
u es wi hin he s udy landscape. Ou aim was o collec
a su icien amoun o compa able da a in o de o ana-
lyse in e speci ic di e ences in mobili y and es ou
hypo heses on he e ec s o speci ic species ai s on bu -
e ly mobili y based on ea lie s udies. Mo e speci ically,
we aimed o answe he ollowing s udy ques ions: (1) Do
bu e lies di e signi ican ly om geome oid and noc u-
oid mo hs in mobili y? (2) Does body size (wingspan)
explain mobili y di e ences be ween bu e ly species? (3)
Which o he species ai s a ec mobili y di e ences
be ween bu e ly species?
Based on p e ious s udies on mo hs (Nieminen 1996;
Nieminen e al. 1999), we hypo hesized geome oids o
be less mobile han noc uoids. Ou expec a ion o he
ela ionship be ween bu e ly and mo h mobili y was less
clea , because much a ia ion has been epo ed in bo h
species g oups and di ec mul ispecies compa isons
be ween bu e lies and mo hs ha e been lacking. How-
e e , ou ea lie esul s o a six-yea se -aside expe imen
showed ha bu e lies colonized he se -aside as e han
diu nal mo hs (Alanen e al. 2011), sugges ing highe
mobili y in bu e lies han mo hs.
Based on ecen me a-analyses on bu e ly mobili y
(S e ens e al. 2010, 2012; Seka 2012) and ou own esul s
on coloniza ion speed in bu e lies (Alanen e al. 2011),
we hypo hesized mobili y o inc ease wi h inc easing body
size (wingspan). The mo i a ion o es he ole o a se o
o he species ai s s ems om ecen s udies epo ing sig-
ni ican e ec s o a ious ai s on bu e ly mobili y (S e-
ens e al. 2010, 2012; Seka 2012). Fu he mo e, we used
he oppo uni y o e ed by ou expe imen al se -up o es
also he e ec o elease habi a sui abili y on mobili y o
species o igina ing om di e en habi a ypes, hypo he-
sizing ha dec easing habi a sui abili y would inc ease
emig a ion a e (Bowle and Ben on 2005). Finally, we also
conside ed he po en ial e ec s o phylogene ic ela edness
on bu e ly mobili y. Cha ac e is ics o closely ela ed spe-
cies a e o en mo e simila compa ed wi h dis an ly ela ed
species, and hus he assump ion o independen da a
poin s may be iola ed in compa a i e analyses including
mul iple species (I es and Zhu 2006).
Ma e ials and Me hods
Expe imen al design and s udy a ea
The expe imen had a simple design in which ma ked
lepidop e an indi iduals we e eleased daily in a
ª2014 The Au ho s. Ecology and E olu ion published by John Wiley & Sons L d. 3801
M. Kuussaa i e al.Highe Mobili y o Bu e lies han Mo hs
25 m 925 m elease a ea wi hin a 11-ha se -aside ield,
which was es ablished eigh yea s ea lie (Fig. 1; o he
o me six-yea se -aside expe imen , see Alanen e al.
2011). Mo emen dis ances o he ma ked indi iduals
we e hen sys ema ically eco ded by ecap u ing hem a
di e en dis ances om he elease a ea bo h wi hin and
ou side he se -aside ield (Fig. 1). This design enabled
us o eco d dis ance mo ed and emig a ion a e in a
compa able manne o a la ge se o bu e ly and
mo h species han o ou knowledge in any p e ious
s udy.
The elease se -aside ield was loca ed in Yp€
aj€
a, sou h-
wes e n Finland (ETRS-TM35FIN N 6745551 E 299807),
in an ag icul u al landscape domina ed by sp ing ce eal
p oduc ion. The landscape su ounding he se -aside ield
was la and open ag icul u al land in all di ec ions excep
owa d he no hwes , whe e he e was a mosaic a ea o
o es s, species- ich semi-na u al g asslands, and buil -up
a eas s a ing om c. 600 m om he se -aside (Fig. 1).
The elease se -aside was occupied by a ela i ely di e se
communi y o g assland bu e lies and diu nal mo hs,
wi h many species e en mo e abundan a he ime o
ou elease expe imen han in yea 2008, when he six-
yea se -aside expe imen ended (see Table S1). Fo
ins ance, Lycaena hippo hoe had clea ly es ablished a local
popula ion on he se -aside a e yea 2008.
Bu e ly and mo h eleases
A o al o 2011 bu e ly and 2367 mo h indi iduals
belonging o 32 bu e ly and 28 mo h species we e
ma ked and eleased in he 25 m 925 m elease a ea
wi hin he se -aside ield ( o a de ailed lis o eleased
species, see Table S1; nomencla u e acco ding o Kull-
be g e al. 2002). Indi iduals o he eleases we e
collec ed om he se -aside ield (40% o eleased indi-
iduals) as well as om he su ounding landscape (nine
si es, 60% o indi iduals). The nine si es we e loca ed
50–3800 m om he elease se -aside ield and we e
good bu e ly habi a s, mos ly pa ches o semi-na u al
g asslands and shel e ed, sunny o es edges wi h some
semi-na u al ege a ion. These si es we e selec ed in
o de o maximize bo h he numbe o indi iduals and
species eleased in he expe imen . Collec ing
(unma ked) indi iduals om hese si es o he eleases
also e ec i ely se ed in collec ing ecap u es o ma ked
indi iduals ha had al eady emig a ed om he elease
se -aside ield (see below).
Bu e lies and diu nal mo hs we e ma ked, eleased,
and ecap u ed daily du ing wo s udy pe iods: om 30
May o 11 June and om 28 June o 14 July 2011. The
i s pe iod co e ed he ligh season o ea ly summe spe-
cies in sou hwes e n Finland, whe eas he second pe iod
co e ed he ligh season o mid-summe species. This
p ocedu e enabled us o co e a la ge p opo ion o bu -
e ly and diu nal mo h species’ occu ence du ing he
summe season. The wea he was mos ly wa m and sunny
(i.e., a o able o lepidop e an ac i i y) du ing he wo
s udy pe iods.
Usually, indi iduals we e collec ed o he eleases om
he elease se -aside ield du ing he mo ning and om
he su ounding landscape du ing he a e noon.
Figu e 1. Ae ial pho og aph o he s udy
a ea. Le e A indica es he elease a ea wi hin
he ocal se -aside ield. The black line wi h
a ows indica es he 2500-m-long ansec in
which ma ked indi iduals we e sys ema ically
sea ched. Solid whi e lines show he sea ching
ou es ou side he elease se -aside, and
dashed whi e lines show he ou es which
we e walked less equen ly. Numbe s 1–4
indica e a o able bu e ly and mo h habi a s,
which we e used bo h o collec ing indi iduals
o he eleases and o sea ching ecap u es o
emig a ed indi iduals; especially si es 1
(abandoned a mya d and a shel e ed o es
edge) and 2 (semi-na u al g assland pa ch)
a ac ed many emig an s.
3802 ª2014 The Au ho s. Ecology and E olu ion published by John Wiley & Sons L d.
Highe Mobili y o Bu e lies han Mo hs M. Kuussaa i e al.
Bu e lies we e always ma ked wi h an indi idual numbe
on he wing using a ine-poin pen, whe eas o he lepi-
dop e an species we e ma ked wi h a colo spo made on
he wing wi h a hicke ma ke pen. The la e was pe -
o med by gen ly p essing he pen h ough he bu e ly
ne wi hou aking he mo h indi idual in hand, in o de
o a oid damaging i s agile wings. Immedia ely a e
ma king, each indi idual was placed indi idually wi hin a
120-ml plas ic con aine which was hen s o ed in a cool
box in o de o keep he ma ked indi iduals inac i e
be o e he elease.
Indi iduals ma ked wi hin he elease se -aside du ing
he mo ning session we e eleased close o he cen e o
he 25 m 925 m elease a ea daily app oxima ely a 12
o’clock, whe eas he ma ked indi iduals collec ed om
he su ounding landscape we e ypically eleased be ween
16 and 18 o’clock. In he elease a ea, he bu e lies and
mo hs we e gen ly placed indi idually on plan lea es and
lowe s. Recap u es we e ne e collec ed wi hin he
25 m 925 m elease a ea.
P o ocol o ecap u es
In collec ing da a on mo emen s o eleased bu e lies
and mo hs, he ocus was on bo h wi hin se -aside mo e-
men s and mo emen s o he su ounding landscape.
The e o e, ecap u es we e sea ched daily in a sys ema ic
way a di e en dis ances om he elease a ea, bo h in
he elease se -aside and in i s su oundings.
App oxima ely one hou was spen on collec ing ecap-
u es wi hin less han 100 me e s om he elease a ea
e e y mo ning. Such a high e o was di ec ed on he el-
a i ely close icini y o he elease a ea in o de o asce -
ain a leas some ecap u es om as many eleased
species as possible, including he leas mobile species. In
addi ion, he whole elease se -aside ield was sys ema i-
cally sea ched h ough by walking a 2500-m-long cons an
ansec (Fig. 1) e e y day. App oxima ely simila e o
was di ec ed on ga he ing ecap u es o emig a ed indi-
iduals in he su ounding landscape. Fig. 1 shows he
ou es along ield ma gins and oad e ges in he icini y
o he elease se -aside ield in which ecap u es we e
sea ched o as o en as ime allowed (almos daily). In
addi ion, ou a o able bu e ly and mo h habi a s
(numbe s 1–4 in Fig. 1) u ned ou o a ac many emi-
g a ed indi iduals, and he e o e, hese a eas we e isi ed
almos daily. In summa y, an a ea o c. 1km
2
was well-
su eyed daily, whe eas in o al ecap u es we e collec ed
om an a ea o c. 4km
2
in size.
Fo each ecap u ed indi idual, he ollowing in o ma-
ion was eco ded: da e, ime, species, sex, indi idual
numbe ( o bu e lies), and he exac loca ion o he
ecap u e, ma ked on an ae ial pho og aph o he a ea.
Measu emen o mo emen pa ame e s
Two main measu es o mobili y we e eco ded o each
species wi h ecap u es: a e age dis ance mo ed and
emig a ion a e.
Dis ance mo ed was measu ed o each ecap u ed bu -
e ly indi idual as he dis ance be ween he elease poin
and he loca ion o he las ecap u e, he eby each indi-
idual con ibu ed o he esul s only once. Fo diu nal
mo hs, which we e no ma ked indi idually, he dis ance
om he elease poin was eco ded o e e y ecap u e
poin . Dis ances mo ed we e measu ed om he ae ial
pho og aphs in which he ecap u e poin s we e ma ked
in he ield. Fo he s a is ical analyses, dis ances mo ed
we e ln- ans o med a e which hey ollowed a no mal
dis ibu ion. An indi idual was conside ed as emig a ed,
i i was ecap u ed ou side he elease se -aside ield.
Based on he same logic as wi h dis ance mo ed, only he
las ecap u e o a bu e ly indi idual was used o indi-
ca ing emig a ion, i espec i e o i s p e ious ecap u e
eco ds. In con as , all ecap u es o mo hs we e consid-
e ed as independen obse a ions.
As a hi d measu e po en ially ela ed o mobili y, he
p opo ion o ecap u ed indi iduals was eco ded o all
s udied species. In p e ious s udies on lepidop e an
mobili y, inc easing ac ion o disappea ed (i.e., no
ecap u ed) indi iduals has some imes been conside ed as
an indica ion o inc easing mobili y o emig a ion
(Kuussaa i e al. 1996; Me ckx e al. 2009). In con as o
he o he wo mobili y measu es which a e solely based
on ecap u es, all eleased lepidop e an indi iduals con-
ibu ed o his measu e and hus he ac ion o ecap-
u ed indi iduals could po en ially gi e some addi ional
in o ma ion on mobili y.
In o de o acili a e an unbiased compa ison o mobil-
i y be ween bu e lies and mo hs in s a is ical analyses,
we also calcula ed all h ee mobili y measu es o bu e -
lies using he same logic as in mo hs, ha is, ea ing
each bu e ly ecap u e as a sepa a e da a poin in he
da a se .
Species ai s
The analyses on he ole o species ai s ocused only on
bu e lies as published species ai da a a e scan y o
mo hs. The ollowing six species ai s we e examined in
o de o explain obse ed mobili y di e ences in bu e -
lies: body size, adul habi a speci ici y and p e e ence,
la al hos plan speci ici y and hos plan ype, and
elease habi a sui abili y. Body size was measu ed as a
con inuous a iable, whe eas all he o he species ai s
we e measu ed as ca ego ical a iables. The ai classi ica-
ions o each s udied species a e shown in Table S2.
ª2014 The Au ho s. Ecology and E olu ion published by John Wiley & Sons L d. 3803
M. Kuussaa i e al.Highe Mobili y o Bu e lies han Mo hs
Body size o each species was measu ed as he a e age
emale wingspan (in mm), based on he Finnish bu e ly
handbook by Ma ila e al. (1990). Adul habi a speci ic-
i y was classi ied as a bina y a iable: habi a specialis s
occupying one o wo and gene alis s occupying mo e han
wo habi a ypes ollowing Ek oos e al. (2010) and o igi-
nally based on Komonen e al. (2004). Habi a p e e ence
had h ee classes: o es edges and clea ings, semi-na u al
g asslands, and ield ma gins in open a mland, ollowing
Kuussaa i e al. (2007). The speci ici y o la al hos plan
use was measu ed as a bina y a iable: mono- and oligoph-
agous species eeding only on one hos plan genus and
polyphagous species eeding on mo e han one plan
genus, based on Komonen e al. (2004). La al hos plan
ype was classi ied o he ollowing ou ca ego ies: woody
plan s (i.e., ees and sh ubs as well as species in he amily
E icaeae), g asses (Poaceae), leguminous plan s (Fabaceae),
and o he he bs, based on Alanen e al. (2011).
Habi a sui abili y o he elease se -aside ield was a
a iable cons uc ed speci ically o ou cu en analyses.
I was based on ex ensi e quan i a i e obse a ions on
he na u al occu ence o he s udied bu e ly species in
he elease se -aside ield, as explained in Table S1. All he
species eleased in ou mobili y expe imen we e classi ied
in o h ee g oups: 1 =species ne e eco ded, 2 =species
wi h 1–5 eco ds, and 3 =species wi h >5 eco ds du ing
yea s 2003–2011. Class 3 ep esen s species o which he
se -aside ield was mos sui able as a b eeding habi a .
This measu e o habi a sui abili y was conside ed as an
empi ically well-jus i ied and o ou pu poses mo e accu-
a e measu e o species habi a p e e ence han he p e i-
ously published classi ica ion, p esen ed abo e.
S a is ical analyses
The i s se o s a is ical analyses ocused on mobili y di -
e ences be ween wo phylogene ically delinea ed species
g oups, bu e lies (Papilionoidea) and geome oid (Geo-
me oidea) mo hs ( an Nieuke ken e al. 2011), using
compa ably calcula ed mobili y a iables as explained
abo e. Noc uoid (Noc uoidea) mo hs we e excluded om
hese analyses, as he e we e only a ew ecap u es (mo e
han one indi idual ecap u ed only in one species;
Table 1).
Di e ences in mean dis ance mo ed be ween he spe-
cies g oups we e es ed using linea mixed models
(LMM) using species g oup as a ca ego ical ixed ac o .
Species was included in he model as a andom ac o in
o de o ake in o accoun he nonindependence o obse -
a ions om di e en indi iduals o he same species.
Model i ing was conduc ed using es ic ed maximum-
likelihood (REML) es ima ion wi h he deg ees o ee-
dom calcula ed acco ding o he Kenwa d–Roge me hod
(Bolke e al. 2009). Di e ences in emig a ion a e and
ecap u e p obabili y be ween he h ee species g oups
we e es ed using he same logic, bu by i ing gene al-
ized mixed models (GLMM) wi h logis ic link unc ion
and binomial e o dis ibu ion (due o bina y esponse
a iables). GLMM i ing was conduc ed using adap i e
Gauss–He mi e quad a u e es ima ion (Bolke e al. 2009)
wi h he deg ees o eedom calcula ed wi h he be ween–
wi hin deg ees o eedom app oxima ion. Fo all h ee
esponse a iables, he pai wise di e ences be ween he
h ee species g oups we e es ed using Tukey’s es .
As he second s ep o analyses, mul i a ia e models
we e buil o examine which combina ions o species
ai s bes explained mobili y di e ences be ween bu e ly
species. He e, only he las ecap u e o each bu e ly
indi idual was aken in o accoun . Also, he sex o each
indi idual was included in hese models, because he
mo i a ion o he wo sexes o mo e and emig a e may
be qui e di e en . Howe e , be o e mul i a ia e model
building, he uni a ia e ela ionships be ween each species
ai , sex and he h ee mobili y measu es we e examined
by building a sepa a e s a is ical model o each species
ai and mobili y measu e (Appendix S1). Pai wise ela-
ionships be ween he explana o y species ai s we e
examined be o e model building in o de o a oid inclu-
sion o collinea explana o y a iables. Consequen ly, wo
species ai s (la al hos plan ype and habi a p e e -
ence) we e omi ed om mul i a ia e model building,
due o signi ican ela ionships wi h o he ai s (Appen-
dix S1). Mo eo e , he po en ial e ec o he o iginal col-
lec ion a ea ( om he se -aside ield o om su ounding
landscape) o he eleased bu e ly indi iduals on mobil-
i y was es ed, and i did no a ec emig a ion a e o dis-
ances mo ed (Appendix S1). Thus, he ole o he sou ce
a ea could be igno ed in he analyses.
Fo wa d selec ion was used in building he LMM and
GLMM wi h mul iple a iables, ha is, he s a is ically
signi ican a iables (P<0.05) we e en e ed in o he
model in he o de o hei explana o y powe . Fo he
only con inuous a iable, body size, bo h linea and qua-
d a ic e ec s we e es ed. S a is ical signi icances we e cal-
cula ed using an F- es . No o e dispe sion was obse ed
in he analyses. Pai wise di e ences be ween he ca ego ies
o he ca ego ical species ai s we e es ed using Tukey’s
es . All LMM and GLMM models desc ibed abo e we e
buil using he s a is ical package SAS/STAT

9.2 (SAS
ins i u e Inc., Ca y, NC).
In o de o ake in o accoun he po en ial e ec s o
phylogene ic ela edness on bu e ly mobili y in ou
s udy, he inal mul i a ia e models o dis ance mo ed
and emig a ion a e we e e i ed using gene alized
es ima ion equa ions (GEE) as implemen ed in he
ape lib a y, e sion 3.0.11 (Pa adis e al. 2004) in he R
3804 ª2014 The Au ho s. Ecology and E olu ion published by John Wiley & Sons L d.
Highe Mobili y o Bu e lies han Mo hs M. Kuussaa i e al.

s a is ical en i onmen (R Co e Team 2013). GEE a e
ex ensions o gene alized linea models (GLMs) o be
applied when he s a is ical nonindependence o he da a
can be de e mined wi h a co ela ion ma ix (Pa adis and
Claude 2002). Pa adis and Claude (2002) ha e demon-
s a ed he applicabili y o GEE in compa a i e s udies
using a be ween-species co ela ion ma ix de i ed om a
phylogene ic ee, and P€
oy y e al. (2009) p o ide a p e i-
ous example on bu e lies. GEE a e especially sui able o
da a ha include ca ego ical a iables (Pa adis and
Claude 2002), as was he case in ou s udy.
To calcula e a co ela ion ma ix o ela edness in
GEE, a phylogene ic hypo hesis was de i ed o he 32
bu e ly species included in ou s udy (Appendix S2).
The b anching sequences o bu e ly amilies we e
de i ed om ecen amily-le el phylogene ic s udies co -
e ing all highe axa o bu e lies (e.g., Heikkil€
a e al.
2011). Placemen o lowe axa down o indi idual species
was deduced om he phylogene ic s udies ocusing spe-
ci ically on each g oup (Appendix S2). B anches wi h
weak suppo o un esol ed b anches in he o iginal s ud-
ies we e ea ed as poly omies. Fo simplici y, all ee
b anches we e assumed o be o equal leng h. In o de o
include indi iduals in he analysis, we placed hem on
species b anches so ha be ween-indi idual dis ances we e
assumed o be 0.01 x species b anch leng h. S a is ical sig-
ni icances we e calcula ed using an F- es , and he phylo-
gene ic hypo hesis was used o calcula e he co ec ed
Table 1. Mobili y esul s o all ecap u ed species: Numbe o eleased indi iduals (n), numbe o ecap u ed indi iduals (RC
ind
), ecap u e p oba-
bili y (%; RC
%
), emig a ion p obabili y (%; Emig
%
), mean dis ance mo ed s anda d e o (m; D
mean
SE), and maximum dis ance mo ed (m;
D
max
). Fo each bu e ly species, he alues in pa en heses indica e he o al numbe o ecap u es and es ima es o emig a ion a e and mean
dis ance mo ed, based on all ecap u es and calcula ed simila ly as in diu nal mo hs.
Species nRC
ind
RC
%
Emig
%
D
mean
SE D
max
Bu e lies
An hocha is ca damines 22 2 (3) 9.1 100 (100) 985 565 (779 386) 1550
Aphan opus hype an us 188 79 (110) 42.0 14 (10) 113 11 (105 8) 510
A icia a axe xes 24 5 (6) 20.8 40 (33) 347 119 (310103) 730
Bolo ia euph osyne 21 4 (5) 19.0 100 (100) 619 96 (586 81) 893
Bolo ia selene 236 40 (45) 16.9 45 (33) 250 43 (237 38) 885
B en his ino 92 35 (56) 38.0 51 (41) 147 19 (138 13) 520
Coenonympha glyce ion 161 25 (34) 15.5 16 (15) 138 21 (132 16) 539
Gonep e yx hamni 44 1 2.3 100 878 878
Lep idea sinapis 56 9 (15) 16.1 100 (100) 488 18 (491 12) 548
Lycaena hippo hoe 33 13 (17) 39.4 8 (12) 84 13 (83 10) 196
Lycaena i gau eae 14 6 (8) 42.9 83 (75) 460 71 (430 67) 550
Meli aea a halia 21 3 14.3 67 339 241 817
Nymphalis io 26 2 (3) 7.7 100 (100) 290 129 (23592) 419
Pie is napi 480 47 (55) 9.8 77 (78) 396 40 (39335) 1720
Polyomma us amandus 253 79 (127) 31.2 19 (20) 119 12 (12010) 520
Polyomma us ica us 25 5 (6) 20.0 40 (33) 191 84 (170 72) 510
Polyomma us semia gus 72 15 (17) 20.8 20 (24) 142 34 (13730) 520
Thymelicus lineola 97 15 (17) 15.5 27 (29) 106 13 (112 13) 214
To al 2011
1
385 (528) 22.2
2
55.9 (53.9)
2
338 (315)
2
Noc uoid mo hs
Callis ege mi 19 1 5.3 0 34 34
C yp ocala cha dinyi 16 1 6.3 100 128 128
Euclidia glyphica 594 40 6.7 10 122 23 913
To al 673
1
42 6.1
2
36.7
2
95
2
Geome oid mo hs
Chiasmia cla h a a 930 41 4.4 0 47 4 130
Ema u ga a oma ia 192 8 4.2 0 64 10 115
Odezia a a a 39 1 2.6 100 120 120
Sco op e yx chenopodia a 348 11 3.2 0 49 9 107
Scopula immo a a 38 2 5.3 0 51 151
Siona linea a 13 2 15.4 0 44 17 61
To al 1694
1
65 5.9
2
16.7
2
63
2
To al all 4378
1
492 16.1
2
45.1
2
250
2
1
Including also species wi h no ecap u es in he da a.
2
Unweigh ed mean o he ecap u ed species.
ª2014 The Au ho s. Ecology and E olu ion published by John Wiley & Sons L d. 3805
M. Kuussaa i e al.Highe Mobili y o Bu e lies han Mo hs
deg ees o eedom o he da a. Fo ecap u e p obabili y,
he models did no con e ge using he GEE app oach.
Resul s
A o al o 385 indi iduals o 18 species o bu e lies and
107 indi iduals o 9 species o mo hs (6 geome oids and
3 noc uoids) we e ecap u ed wi hin he elease se -aside
ield (328 indi iduals) and in i s su oundings (164 indi-
iduals). Table 1 summa izes in o ma ion on he eleased
and ecap u ed indi iduals and hei mobili y o all spe-
cies wi h a leas one ecap u e ( o in o ma ion on all
eleased species, see Table S1).
Di e ences be ween bu e lies and mo hs
The wo compa ed species g oups, bu e lies and geome -
oid mo hs, di e ed signi ican ly in all h ee examined
measu es o mobili y (Table 2, Fig. 2). Bu e lies we e
mo e mobile han geome oids as indica ed by hei
longe mean dis ances mo ed (315 m s. 63 m) and
highe emig a ion a e (54% s. 17%). The highe ecap-
u e a e o bu e lies han geome oids (22% s. 6%)
mos p obably e lec ed he be e de ec abili y in bu e -
lies han geome oids. The mobili y o noc uoid mo hs
seemed o be somewhe e be ween bu e lies and geome -
oids (Table 1), bu he noc uoid da a we e oo limi ed
o allow meaning ul s a is ical analyses.
Bu e ly mo emen s in ela ion o species
ai s
The s udied bu e ly species showed a lo o in e speci ic
a ia ion in mobili y. A e age dis ance mo ed a ied
om 84 m and 106 m in he wo mos seden a y species
(Lycaena hippo hoe and Thymelicus lineola, espec i ely) o
619 m and 985 m in he wo mos mobile species (Bolo-
ia euph osyne and An hocha is ca damines, espec i ely).
Emig a ion om he elease se -aside ield a ied om
8% (L. hippo hoe) and 14% (Aphan opus hype an us) o
100% in i e o he s udied species (Table 1).
Two species ai s, elease habi a sui abili y and body
size, became included oge he in he mul i a ia e models
bes explaining he wo main mobili y a iables, dis ance
mo ed (LMM) and emig a ion a e (GLMM) (Table 3A).
The e ec s o he wo ai s we e e y simila in bo h
models. Dis ance mo ed and emig a ion a e we e lowe
in bu e ly species o which habi a sui abili y was he
highes . Fu he mo e, bo h dis ance mo ed and emig a-
ion a e ended o inc ease wi h inc easing body size,
when he e ec o habi a sui abili y was aken in o
accoun (see also Fig. 3A and C).
Fo he hi d mobili y a iable, ecap u e a e, body
size, and sex we e he wo a iables included oge he in
he mul i a ia e GLMM (Table 3A). The e ec o body
size became signi ican only when i s nonlinea compo-
nen was included in he model. Recap u e a e was high-
es in bu e ly species o in e media e size and
pa icula ly low in he la ges species eleased in he
Table 2. LMM and GLMM esul s on he di e ences in he h ee
mobili y a iables be ween bu e lies and geome oid mo hs. The di -
e ences be ween he species g oups emained signi ican in all h ee
a iables when he models we e e i ed o he subse o species o
which he elease se -aside p o ided sui able habi a ( elease habi a
sui abili y class =3).
Response
a iable Model n
d (nume a o :
denomina o ) FP
Dis ance mo ed LMM 593 1:23.2 14.71 0.0008
Emig a ion a e GLMM 593 2:22 8.22 0.0090
Recap u e a e GLMM 3848 2:52 16.69 0.0002
(A) (B) (C)
Figu e 2. Di e ences in (A) mean dis ance mo ed, (B) emig a ion a e, and (C) ecap u e a e be ween bu e lies and geome oid mo hs. Means
a e leas squa es means (LSM) wi h 95% con idence in e als based on he s a is ical models i ed o collec ed da a (Table 2). The as e isks
indica e he s a is ical di e ence be ween he species g oups (**P<0.01, ***P<0.001).
3806 ª2014 The Au ho s. Ecology and E olu ion published by John Wiley & Sons L d.
Highe Mobili y o Bu e lies han Mo hs M. Kuussaa i e al.
expe imen . The signi ican e ec o sex was due o he
highe ecap u e a e o males han emales.
When he inal LMM and GLMM models we e e i ed
using gene alized es ima ion equa ions (GEE) in o de o
ake in o accoun he po en ial e ec s o phylogene ic
ela edness, he esul s changed sligh ly (Table 3B). In he
GEE model o dis ance mo ed, he e ec o body size
did no emain signi ican (P=0.14), bu habi a sui abil-
i y s ill had a signi ican e ec . In he GEE model o
emig a ion a e, bo h habi a sui abili y and body size had
a signi ican e ec .
Discussion
The elease expe imen success ully p oduced di ec ly com-
pa able mobili y da a o bu e lies and mo hs. Recap u es
we e collec ed om almos 500 indi iduals belonging o 27
species. The da a se enabled us bo h o de ec di e ences
in mobili y be ween wo lepidop e an supe amilies and o
iden i y signi ican e ec s o species ai s on dis ance
mo ed and emig a ion a e in 18 species o bu e lies.
Di e ences be ween bu e lies and mo hs
As expec ed, expe imen ally eleased bu e lies we e
mo e mobile han hin-bodied, weakly lying geome oid
mo hs in e ms o bo h dis ance mo ed and emig a ion
a e. Bu e ly mo emen dis ances we e on he a e age
i e imes longe and emig a ion a e h ee imes highe
han in geome oid mo hs. Da a o noc uoid mo hs
emained oo spa se o in e any gene al esul s. Ou
indings a e in ag eemen wi h ou p e ious esul s on
coloniza ion o se -asides by bu e lies and diu nal
mo hs (Alanen e al. 2011) and an expe imen compa ing
mobili y o lepidop e an species g oups (Nieminen 1996)
in a ne wo k o small islands. Like ou esul s, he esul s
o Nieminen also sugges ed ha bu e lies a e mos and
hin-bodied geome oids leas mobile, whe eas noc uoids
show in e media e mobili y. I should be no ed, howe e ,
ha Nieminen s udied only wo bu e ly species, Vanessa
a alan a and Hippa chia semele, o which V. a alan a is
known as a egula long-dis ance mig an , ep esen ing
one o he mos mobile bu e ly species occu ing in
Eu ope (S e anescu 2001).
Recap u e a e was gene ally much lowe in diu nal
mo hs han in bu e lies. We a gue ha he e a e wo
likely easons o his: he lowe ligh ac i i y and hus
he lowe de ec abili y o mo hs and he highe popula-
ion densi ies o he mos abundan mo hs compa ed o
he mos abundan bu e lies. Based on he obse ed el-
a i e abundances o ma ked s. unma ked indi iduals in
he elease se -aside ield, we es ima ed ha he geome -
oid Semio hisa cla h a a and he noc uoid Euclidia glyph-
ica, o ins ance, we e an o de o magni ude mo e
abundan han he mos abundan bu e lies, such as
Aphan opus hype an us and Polyomma us amandus. Ne -
e heless, due o ou sys ema ic sampling p o ocol, he
ela i e ecap u e p obabili ies o he s udied axonomic
g oups did no di e a di e en dis ances om he
elease poin , and hus he mobili y esul s can be eliably
compa ed be ween di e en species and species g oups.
Ou esul s indica e ha i is mo e di icul o ob ain eli-
able mobili y da a om diu nal mo hs han bu e lies by
ma k– elease– ecap u e me hod.
In ligh o he heo e ical model by T a is and Dy-
ham (1999), he obse ed pa e n o mobili y a ia ion
ac oss mo h and bu e ly species in ou expe imen has
po en ial consequences o species pe sis ence. Acco ding
o hei p edic ions, species wi h ei he low o high
Table 3. Resul s o he inal mul i a ia e models (LMM, GLMM, and
GEE) o he h ee s udied mobili y a iables. (A) LMM and GLMM
models wi hou accoun ing o he phylogene ic ela edness. (B) GEE
models accoun ing o he phylogene ic ela edness among species
Model
1
Es ima e SE d FP
(A)
Dis ance mo ed (LMM)
Cons an 3.354 0.589
Hab
sui
2:30.5 15.57 <0.001
Class 1 1.168 0.278
Class 2 1.316 0.325
Body size 0.042 0.017 1:27.8 6.21 0.019
Emig a ion a e (GLMM)
Cons an 5.517 1.850
Hab
sui
2:14 6.76 0.009
Class 1 3.334 1.195
Class 2 2.384 0.967
Body size 0.139 0.054 1:14 6.70 0.022
Recap u e a e (GLMM)
Cons an 12.468 4.301
Body size 0.605 0.238 1:29 6.48 0.017
Body size*Body size 0.009 0.003 1:29 7.08 0.013
Sex 1:22 6.32 0.020
Male 0.372 0.148
(B)
Dis ance mo ed (GEE)
2
Hab
sui 3
0.729 0.186 2 29.43 0.011
Body size 0.039 0.020 1 3.95 0.141
Emig a ion a e (GEE)
2
Hab
sui 3
1.315 0.739 2 13.99 0.030
Body size 0.141 0.028 1 25.19 0.015
Hab
sui
= elease habi a sui abili y (Class 1 =unsui able, Class
2= ai ly unsui able, Class 3 =sui able habi a o b eeding), Body
size =wingspan (mm).
1
GEE Model o ecap u e p obabili y did no con e ge.
2
Phylogene ic deg ees o eedom: 7.00.
3
Habi a sui abili y (Hab
sui
) was ea ed as an o de ed ac o in bo h
models, and model es ima es o linea con as s a e p esen ed in he
able.
ª2014 The Au ho s. Ecology and E olu ion published by John Wiley & Sons L d. 3807
M. Kuussaa i e al.Highe Mobili y o Bu e lies han Mo hs
dispe sal a e should pe o m bes in highly agmen ed
landscapes, whe eas species wi h in e media e mobili y
a e p edic ed o pe o m wo s . Ou indings seem o i
hese p edic ions because he geome oid mo hs, ha
we e ound o be he leas mobile lepidop e ans, ha e
no declined in Finland (Hulden e al. 2000) and a e
ypically common and abundan in many kinds o
uncul i a ed g assland. Simila ly, la ge bu e ly species
wi h high mobili y ha e no su e ed om habi a ag-
men a ion, whe eas some g assland specialis bu e lies
wi h in e media e mobili y, such as L. hippo hoe, ha e
disappea ed om many in ensi ely cul i a ed landscapes
(Ek oos and Kuussaa i 2012). This model p edic ion has
p e iously ecei ed empi ical suppo om B i ish bu -
e lies (Thomas 2000).
Bu e ly mo emen s in ela ion o species
ai s
Bu e ly mobili y was s ongly a ec ed by habi a sui -
abili y. Bu e lies ended o quickly emig a e om he
elease se -aside ield, i i did no o e sui able b eeding
habi a o he species in ques ion. Body size explained
addi ional a ia ion in mobili y a e he e ec o habi a
sui abili y had been aken in o accoun in he s a is ical
models. Bo h dis ance mo ed and emig a ion a e
inc eased wi h body size, as expec ed based on ou ea lie
esul s on bu e ly coloniza ion speed (Alanen e al.
2011) and me a-analyses on bu e ly mobili y (S e ens
e al. 2010, 2012; Seka 2012). When phylogene ic
ela edness among species was included in he analyses,
(A) (B)
(C) (D)
(E) (F)
Figu e 3. S a is ically signi ican ela ionships
be ween species ai s and he h ee mobili y
a iables: (A–B) dis ance mo ed, (C–D)
emig a ion a e, and (E–F) ecap u e a e in
bu e lies. Means a e leas squa es means
(LSM) wi h 95% con idence in e als based on
he mul i a ia e models i ed o collec ed da a
(Table 3). In he panels A, C, and E, he do s
ep esen means o indi idual species. The
le e s a and b wi hin he panels B, D, and F
indica e homogeneous g oups and hus he
ea men s which di e ed signi ican ly in
pai wise compa isons.
3808 ª2014 The Au ho s. Ecology and E olu ion published by John Wiley & Sons L d.
Highe Mobili y o Bu e lies han Mo hs M. Kuussaa i e al.