1 23

Polar Biology ISSN 0722-4060Volume 35Number 3 Polar Biol (2012) 35469-473DOI 101007s00300-011-1082-2

Vagrant Subantarctic fur seal at CapeShirreff Livingston Island Antarctica

Daniel Torres Jorge Acevedo DanielE Torres Romeo Vargas amp AnelioAguayo-Lobo

1 23

Your article is protected by copyright and

all rights are held exclusively by Springer-

Verlag This e-offprint is for personal use only

and shall not be self-archived in electronic

repositories If you wish to self-archive your

work please use the accepted authorrsquos

version for posting to your own website or

your institutionrsquos repository You may further

deposit the accepted authorrsquos version on a

funderrsquos repository at a funderrsquos request

provided it is not made publicly available until

12 months after publication

Polar Biol (2012) 35469ndash473

Authors personal copy

DOI 101007s00300-011-1082-2

SHORT NOTE

Vagrant Subantarctic fur seal at Cape ShirreV Livingston Island Antarctica

Daniel Torres middot Jorge Acevedo middot Daniel E Torres middot Romeo Vargas middot Anelio Aguayo-Lobo

Received 15 June 2011 Revised 21 July 2011 Accepted 9 August 2011 Published online 23 August 2011copy Springer-Verlag 2011

Abstract A vagrant adult male Subantarctic fur sealArctocephalus tropicalis was observed among Antarctic furseals A gazella at Cape ShirreV Livingston Island Antarc-tica which is located to raquo4190 and raquo5939 km from thenearest breeding colonies of Subantarctic fur seals Althoughthe colony of origin of this animal and the reason for itsmovement outside its distribution range are unknown thissighting shows the high dispersal capacity of this speciesand provides an insight into possible changes in its distribu-tion Although this vagrant was not observed with femalesAntarctic fur seal news sightings in the future could result in

viable hybrid and introgressive hybridization could repre-sent a threat for Cape ShirreV population recovery if still thepopulation way to go to recover to presailing levels

Keywords Arctocephalus tropicalis middot Fur seals middot South Shetland Islands middot Dispersion

Introduction

The Subantarctic fur seal Arctocephalus tropicalis Gray1872 hauls out to breed on islands north of the AntarcticPolar Front (APF) (Bester 1984) with the major concentra-tions occurring on cool-temperate Gough Island in theSouth Atlantic and Amsterdam Island in the Indian Oceanas well as at the Subantarctic Prince Edward Islands Archi-pelago in the Indian Ocean Smaller colonies are also foundon Icircle Saint Paul Icircle de la Possession (Icircles Crozet) theTristan da Cunha group and Macquarie Island (Bonner1981 Bester et al 2003 2006 Hofmeyr et al 2006a Lan-caster et al 2006) Moreover small numbers haul out southof the Antarctic Polar Front (APF) on Subantarctic HeardIsland where single pups have been recorded during anumber of seasons since 1987 (Goldsworthy and Shaugh-nessy 1989 httpwwwsealsscarorgpdfstatusofstocspdf) (Fig 1)

Recent studies of foraging ecology have provided con-siderable information on the marine movements and disper-sion of lactating females Subantarctic fur seal within theirdistribution range (eg Bester 1989 Georges et al 2000Robinson et al 2002 Beauplet et al 2004 de Bruyn et al2009) However a great deal remains unknown andvagrant individuals mostly males have been recorded atgreat distances (up to 7000 km) outside of their commondistribution range

D TorresFacultad de Ciencias Agropecuarias Universidad Pedro de Valdivia Escuela de Medicina Veterinaria Campus Tobalaba Av Tobalaba 1275 Providencia Santiago Chile

J AcevedoFundacioacuten Centro de Estudios del Cuaternario (CEQUA) Av Bulnes 01890 Punta Arenas Chile

J Acevedo (amp)Universidad de Magallanes Av Bulnes 01855 Punta Arenas Chilee-mail jorgeacevedocequacl

D E TorresFacultad de Ciencias Agropecuarias y Ambientales Universidad de Las Ameacutericas Escuela de Medicina Veterinaria Av Walker Martiacutenez 1360 La Florida Santiago Chile

R VargasDepartamento Medio Ambiente Acuaacutetico Gobernacioacuten Mariacutetima de Castro Chiloeacute Chile

A Aguayo-LoboInstituto Antaacutertico Chileno (INACH) Plaza Muntildeoz Gamero 1055 Punta Arenas Chile

123

1 23

Your article is protected by copyright and

all rights are held exclusively by Springer-

Verlag This e-offprint is for personal use only

and shall not be self-archived in electronic

repositories If you wish to self-archive your

work please use the accepted authorrsquos

version for posting to your own website or

your institutionrsquos repository You may further

deposit the accepted authorrsquos version on a

funderrsquos repository at a funderrsquos request

provided it is not made publicly available until

12 months after publication

Polar Biol (2012) 35469ndash473

Authors personal copy

DOI 101007s00300-011-1082-2

SHORT NOTE

Vagrant Subantarctic fur seal at Cape ShirreV Livingston Island Antarctica

Daniel Torres middot Jorge Acevedo middot Daniel E Torres middot Romeo Vargas middot Anelio Aguayo-Lobo

Received 15 June 2011 Revised 21 July 2011 Accepted 9 August 2011 Published online 23 August 2011copy Springer-Verlag 2011

Abstract A vagrant adult male Subantarctic fur sealArctocephalus tropicalis was observed among Antarctic furseals A gazella at Cape ShirreV Livingston Island Antarc-tica which is located to raquo4190 and raquo5939 km from thenearest breeding colonies of Subantarctic fur seals Althoughthe colony of origin of this animal and the reason for itsmovement outside its distribution range are unknown thissighting shows the high dispersal capacity of this speciesand provides an insight into possible changes in its distribu-tion Although this vagrant was not observed with femalesAntarctic fur seal news sightings in the future could result in

viable hybrid and introgressive hybridization could repre-sent a threat for Cape ShirreV population recovery if still thepopulation way to go to recover to presailing levels

Keywords Arctocephalus tropicalis middot Fur seals middot South Shetland Islands middot Dispersion

Introduction

The Subantarctic fur seal Arctocephalus tropicalis Gray1872 hauls out to breed on islands north of the AntarcticPolar Front (APF) (Bester 1984) with the major concentra-tions occurring on cool-temperate Gough Island in theSouth Atlantic and Amsterdam Island in the Indian Oceanas well as at the Subantarctic Prince Edward Islands Archi-pelago in the Indian Ocean Smaller colonies are also foundon Icircle Saint Paul Icircle de la Possession (Icircles Crozet) theTristan da Cunha group and Macquarie Island (Bonner1981 Bester et al 2003 2006 Hofmeyr et al 2006a Lan-caster et al 2006) Moreover small numbers haul out southof the Antarctic Polar Front (APF) on Subantarctic HeardIsland where single pups have been recorded during anumber of seasons since 1987 (Goldsworthy and Shaugh-nessy 1989 httpwwwsealsscarorgpdfstatusofstocspdf) (Fig 1)

Recent studies of foraging ecology have provided con-siderable information on the marine movements and disper-sion of lactating females Subantarctic fur seal within theirdistribution range (eg Bester 1989 Georges et al 2000Robinson et al 2002 Beauplet et al 2004 de Bruyn et al2009) However a great deal remains unknown andvagrant individuals mostly males have been recorded atgreat distances (up to 7000 km) outside of their commondistribution range

D TorresFacultad de Ciencias Agropecuarias Universidad Pedro de Valdivia Escuela de Medicina Veterinaria Campus Tobalaba Av Tobalaba 1275 Providencia Santiago Chile

J AcevedoFundacioacuten Centro de Estudios del Cuaternario (CEQUA) Av Bulnes 01890 Punta Arenas Chile

J Acevedo (amp)Universidad de Magallanes Av Bulnes 01855 Punta Arenas Chilee-mail jorgeacevedocequacl

D E TorresFacultad de Ciencias Agropecuarias y Ambientales Universidad de Las Ameacutericas Escuela de Medicina Veterinaria Av Walker Martiacutenez 1360 La Florida Santiago Chile

R VargasDepartamento Medio Ambiente Acuaacutetico Gobernacioacuten Mariacutetima de Castro Chiloeacute Chile

A Aguayo-LoboInstituto Antaacutertico Chileno (INACH) Plaza Muntildeoz Gamero 1055 Punta Arenas Chile

123

Polar Biol (2012) 35469ndash473

Authors personal copy

DOI 101007s00300-011-1082-2

SHORT NOTE

Vagrant Subantarctic fur seal at Cape ShirreV Livingston Island Antarctica

Daniel Torres middot Jorge Acevedo middot Daniel E Torres middot Romeo Vargas middot Anelio Aguayo-Lobo

Received 15 June 2011 Revised 21 July 2011 Accepted 9 August 2011 Published online 23 August 2011copy Springer-Verlag 2011

Abstract A vagrant adult male Subantarctic fur sealArctocephalus tropicalis was observed among Antarctic furseals A gazella at Cape ShirreV Livingston Island Antarc-tica which is located to raquo4190 and raquo5939 km from thenearest breeding colonies of Subantarctic fur seals Althoughthe colony of origin of this animal and the reason for itsmovement outside its distribution range are unknown thissighting shows the high dispersal capacity of this speciesand provides an insight into possible changes in its distribu-tion Although this vagrant was not observed with femalesAntarctic fur seal news sightings in the future could result in

viable hybrid and introgressive hybridization could repre-sent a threat for Cape ShirreV population recovery if still thepopulation way to go to recover to presailing levels

Keywords Arctocephalus tropicalis middot Fur seals middot South Shetland Islands middot Dispersion

Introduction

The Subantarctic fur seal Arctocephalus tropicalis Gray1872 hauls out to breed on islands north of the AntarcticPolar Front (APF) (Bester 1984) with the major concentra-tions occurring on cool-temperate Gough Island in theSouth Atlantic and Amsterdam Island in the Indian Oceanas well as at the Subantarctic Prince Edward Islands Archi-pelago in the Indian Ocean Smaller colonies are also foundon Icircle Saint Paul Icircle de la Possession (Icircles Crozet) theTristan da Cunha group and Macquarie Island (Bonner1981 Bester et al 2003 2006 Hofmeyr et al 2006a Lan-caster et al 2006) Moreover small numbers haul out southof the Antarctic Polar Front (APF) on Subantarctic HeardIsland where single pups have been recorded during anumber of seasons since 1987 (Goldsworthy and Shaugh-nessy 1989 httpwwwsealsscarorgpdfstatusofstocspdf) (Fig 1)

Recent studies of foraging ecology have provided con-siderable information on the marine movements and disper-sion of lactating females Subantarctic fur seal within theirdistribution range (eg Bester 1989 Georges et al 2000Robinson et al 2002 Beauplet et al 2004 de Bruyn et al2009) However a great deal remains unknown andvagrant individuals mostly males have been recorded atgreat distances (up to 7000 km) outside of their commondistribution range

D TorresFacultad de Ciencias Agropecuarias Universidad Pedro de Valdivia Escuela de Medicina Veterinaria Campus Tobalaba Av Tobalaba 1275 Providencia Santiago Chile

J AcevedoFundacioacuten Centro de Estudios del Cuaternario (CEQUA) Av Bulnes 01890 Punta Arenas Chile

J Acevedo (amp)Universidad de Magallanes Av Bulnes 01855 Punta Arenas Chilee-mail jorgeacevedocequacl

D E TorresFacultad de Ciencias Agropecuarias y Ambientales Universidad de Las Ameacutericas Escuela de Medicina Veterinaria Av Walker Martiacutenez 1360 La Florida Santiago Chile

R VargasDepartamento Medio Ambiente Acuaacutetico Gobernacioacuten Mariacutetima de Castro Chiloeacute Chile

A Aguayo-LoboInstituto Antaacutertico Chileno (INACH) Plaza Muntildeoz Gamero 1055 Punta Arenas Chile

123

470 Polar Biol (2012) 35469ndash473

Authors personal copy

Extraterritorial occurrences of individual of Subantarcticfur seal (known as vagrants see Fig 1) have been reportedon the coasts of Africa (Shaughnessy and Ross 1980 Carret al 1985 Zanre and Bester 2011) South America (BrazilUruguay and Argentina) (Castello and Pinedo 1977 Ximeacute-nez 1980 Pinedo 1990 Gonzaacutelez et al 1994 Oliveira et al2001 Naya and Achaval 2006 Ferreira et al 2008) andAustralia (Gales et al 1992 Mawson and Coughran 1999httpwwwbiealaorgauspeciesurnlsidbiodiversityorga)and on islands such as Alejandro Selkirk in Juan Fernan-dez Archipelago (Torres and Aguayo-Lobo 1984 Torreset al 1984) New Zealand (Taylor 1990) the Comores(David et al 1993) Madagascar (Garrigue and Ross1996) Mauritius and Rodrigues (David and Salmon2003) and Zanzibar Tanzania (Hofmeyr and Amir 2010)Some of these extraterritorial movements may haveresulted in hybridization with other Arctocephalus species(Torres et al 1984) To the best of our knowledge somevagrant Subantarctic fur seal have only been reportedsouth to the APF at South Georgia (54deg30S Payne 1979)

Bouvet Island (54deg25S Hofmeyr et al 2006b) and IcirclesKerguelen (49deg20S Wynen et al 2000) The southern-most record is reported at Mawson station Antarctica(67deg36S Shaughnessy and Burton 1986) In view of theabove here we report on the Wrst sighting of a vagrantSubantarctic fur seal in the most important breeding colo-nies of Antarctic fur seal at South Shetland IslandsAntarctica

Materials and methods

Cape ShirreV and San Telmo Islets Livingston Island(62deg27S 60deg47W) recognized as Antarctic SpeciallyProtected Area (ASPA) No 149 (see Fig 1) shelters themost important breeding colonies of Antarctic fur seal(A gazella Peters 1875) on the South Shetland Islands(Aguayo-Lobo 1978 Bengtson et al 1988 Meyer et al1996) As part of the Weld work of INACH 018 ProjectldquoEcological studies on the Antarctic fur seal Arctocephalus

Fig 1 Map showing location of sites mentioned in the text In mapa Wlled circle shows the breeding concentrations and the stars indicatethe location of recorded vagrants of A tropicalis In map b the encir-

cled star indicate the location of sighting at Cape ShirreV referred inthe text Map c shows the vagrant adult male Subantarctic fur seal to-gether with an Antarctic fur seal sighted at ldquoEl Plaacutesticordquo beach

123

Polar Biol (2012) 35469ndash473 471

Authors personal copy

gazellardquo periodic censuses of Antarctic fur seal were carriedout by seal biologists and Weld assistants starting from earlyDecember to late February on all beaches of the southwestwest and north coasts of Cape ShirreV while the fewbeaches on the east coast were searched at least twice permonth While performing standard research activitiesunusual sightings of vagrant bird or mammal species havecontinually been approached in a discreet manner intendingnot to disrupt the animalrsquos behavior while recording andphotographing interactions with other species

Results

On December 17 2005 an adult male Subantarctic fur sealwas seen by one of us in ldquoEl Plaacutesticordquo beach where periph-eral adult male and juvenile Antarctic fur seals are com-mon The identiWcation of A tropicalis was based in theirshort head robustness build pale face and neck tuft of hairon top the head as well as itrsquos broad and relatively shortfore Xippers in comparison to those of an Antarctic fur seal(see Fig 1) This individual was apparently in excellentphysical condition and remained on the beach until January10 2006 No tags were observed on its fore Xippers Duringthe subsequent visits to the where the vagrant was locatedperformed between December 17 2005 to January 102006 this fur seal was observed resting in prone positionwith adult male Antarctic fur seals blocking its path to thewater Avoidance behavior was evident to human presenceAfter that date ldquoEl Plaacutesticordquo beach as well as other beachesof the Cape were visited on several occasions but the indi-vidual was not seen again

Discussion

The record of an A tropicalis at Cape ShirreV is an unusualevent the only vagrant Subantarctic fur seals recorded southof the APF have been reported at South Georgia (Payne1979) Bouvet Island (Hofmeyr et al 2006b) Icircles Kerguelen(Wynen et al 2000) and Mawson station Antarctica(67deg36S Shaughnessy and Burton 1986) To the best of ourknowledge our record of an adult male Subantarctic fur sealis the second southernmost record for the species

Given the lack of identiWcation tags it is diYcult toestablish the colony of origin of this individual given thatvagrant Subantarctic fur seals are capable of movingremarkable distances from their natal colonies (up to7000 km) (Torres et al 1984 Bester 1989 Ferreira et al2008) Non-vagrant lactating females are also capable ofmoving long distances (lt2000 km) (Georges et al 2000Robinson et al 2002 Beauplet et al 2004 de Bruyn et al2009)

The nearest breeding colonies of Subantarctic fur sealsto Cape ShirreV (62deg27S) are raquo4190 and raquo5939 km tonortheast on Gough Island in the South Atlantic and thePrince Edward Islands Archipelago in the Indian Oceanrespectively These two localities harbor 85 of the globalpopulation of this species (httpwwwsealsscarorgpdfstatusofstocspdf) While long-range movements from theirnatal site including against the direction of Xow of oceaniccurrents do not seem to be a hindrance for penguins andpinnipeds (eg Torres et al 1984 Fabiani et al 2003Ferreira et al 2008 Biuw et al 2010) many of the vagrantSubantarctic fur seals reported on the Atlantic coast ofSouth America are found in either debilitated conditions ordead (Castello and Pinedo 1977 Naya and Achaval 2006Ferreira et al 2008) Given the good physical condition ofthe vagrant reported here we speculate that this animalmay have rested by making fortuitous rest stops during itsmovement toward the southwest on Subantarctic islandswhile crossing the strong eastward Xow of the AntarcticCircumpolar Current in areas associated with high oceano-graphic heterogeneity (eg anticyclonic and cycloniceddies) In fact these sharp spatial variations in ocean cur-rents were associated with a long-range migration of a chin-strap penguin from Bouvet to South Sandwich Islands(Biuw et al 2010)

Alternatively the vagrant specimen could also havereached Cape ShirreV with assistance of the West WindDrift moving clockwise around Antarctica from its natalcolony Similar paths have been suggested for a vagrantSubantarctic fur seal from Amsterdam Islands found atAlejandro Selkirk Juan Fernandez Archipelago (Torreset al 1984 Ferreira et al 2008) and for seals from CrozetIslands found on the Brazilian coast (Ferreira et al 2008)as well as for southern elephant seals Mirounga leonina(Fabiani et al 2003 Bester and Reisinger 2010 Reisingerand Bester 2010)

This species suVered severe population reductionbetween the eighteenth and twentieth centuries with thelocal extinction of some colonies After the cessation ofsealing surviving populations grew rapidly and historicalbreeding sites were recolonised (Wynen et al 2000) It hasbeen suggested that the dispersion of individuals outsidetheir normal distribution ranges may be linked to high ratesof population increase and increased density at optimalbreeding sites (Bester 1981 Pinedo 1990)

The marine environment is highly dynamic with largescale changes considerably altering environmental vari-ables and prey structure over a time (Hare and Mantua2000 Weimerskirch et al 2003) This may aVect the forag-ing patterns of marine predators and their reproductive suc-cess (Lea et al 2006) Increases in the sea surfacetemperature due to global warming or anomalies in theocean currents or other oceanographic factors such as El

123

472 Polar Biol (2012) 35469ndash473

Authors personal copy

Nintildeo Southern Oscillation (ENSO) events may also drasti-cally change marine productivity in the short to mid-term(months to years) (Fiedler 2002) altering the location offoraging zones and reproductive success in marine predatorspecies (Trillmich and Limberger 1985 Guinet et al 1994Lea et al 2006) These changes have been suggested as apossible explanation for the high numbers of vagrant ofSubantarctic and Antarctic fur seals recorded on the easterncoast of South America in speciWc years (Oliveira et al2001) ENSO events have also been suggested as explana-tions for the dispersion and establishment of new coloniesof South American fur seals A australis in the north ofChile (Torres 1985) Negative anomalies in the SouthernOcean Index (see httpwwwcpcnoaagovdataindices)as evidence during 19971998 and 20042005 summersmay have led to a weaker Antarctic Polar Fronts that shiftedsouth during the winter (Aguayo-Lobo et al 1998)

The presence of this vagrant at Cape ShirreV at thebeginning of the Antarctic fur seal breeding period isimportant because it cautions that in addition to the highdispersal capacity of this fur seal species interbreedingwith other Arctocephalus species (Condy 1978 Torreset al 1984 Goldsworthy et al 1999 Wynen et al 2000Hofmeyr et al 2006a) Although this vagrant was notobserved with females Antarctic fur seal news sightings inthe future could result in viable hybrid fur seals (Kerley1983 Lancaster et al 2006 Kingston and Gwillian 2007Goldsworthy et al 2009) and introgressive hybridizationcould represent a threat for Cape ShirreV population recov-ery if still the population way to go to recover to presailinglevels

Acknowledgments We thank the director of INACH for supportuntil 2006 for the INACH-018 Project ldquoEcological studies of theAntarctic Fur Seal Arctocephalus gazellardquo and the Director ofCEQUA for their support to our respective marine mammal projectsWe also thank Shanon Cunning and Greg Hofmeyr for improvementsto this manuscript

References

Aguayo-Lobo A (1978) The present status of the Antarctic fur sealArctocephalus gazella at South Shetland Islands Polar Rec19167ndash176

Aguayo-Lobo A Acevedo J Torres D (1998) InXuencia del fenoacutemenoldquoEl Nintildeordquo en el estrecho BransWeld Antaacutertica durante junio de1998 Ser Cient INACH 48161ndash184

Beauplet G Dubroca L Guinet C Cherel Y Dabin W Gagne C Hin-dell MA (2004) Foraging ecology of subantarctic fur seals (Arc-tocephalus tropicalis) breeding on Amsterdam Island seasonalchanges in relation to maternal characteristics and pup growthMar Ecol Prog Ser 273211ndash225

Bengtson JL Ferm LM Harkonen TJ Schaner EG Stewart BS (1988)Survey of Antarctic fur seals in the South Shetland Islands Ant-arctica during the 1986ndash1987 Austral summer NOAA TechnicalMemorandum NMFS-FNEC-60

Bester MN (1981) Seasonal changes in the population composition ofthe fur seal Arctocephalus tropicalis at Gough Island S Afr JWildl Res 1149ndash55

Bester MN (1984) Status of the fur seals Arctocephalus tropicalis andArctocephalus gazella north of the Antarctic Convergence S AfrJ Sci 8027ndash28

Bester MN (1989) Movements of southern elephant seals and subant-arctic fur seals in relation to Marion Island Mar Mamm Sci5257ndash265

Bester MN Reisinger RR (2010) Antarctic fur seals at Gough Island in2009 Polar Biol 33709ndash711 doi101007s00300-009-0749-4

Bester MN Ryan PG Dyer BM (2003) Population numbers of furseals at Prince Edward Island Southern Ocean Afr J Mar Sci25549ndash554

Bester MN Wilson JW Burle M-H Hofmeyr GJG (2006) Populationtrends of Subantarctic fur seals at Gough Island S Afr J Wildl Res36191ndash194

Biuw M Lydersen C De Bruyn NPJ Arriola A Hofmeyr GGJ Kritz-inger P Kovacs KM (2010) Long-range migration of a chinstrappenguin from Bouvetoslashya to Montagu Island South SandwichIslands Antarct Sci 22157ndash162 doi101017S0954102009990605

Bonner WN (1981) Southern Fur Seals Arctocephalus (GeoVroy Saint-Hilaire and Cuvier 1826) In Ridgway SH Harrison FRS (eds)Handbook of Marine Mammals Sea Lions Fur Seals and SeaOtter vol 1 The Walrus Academic Press London pp 161ndash208

Carr T Carr N David JHM (1985) A record of the subantarctic fur sealArctocephalus tropicalis in Angola S Afr J Wildl Res 2077

Castello HP Pinedo MC (1977) Arctocephalus tropicalis primeiroregistro para a costa do Rio Grande do Sul (Pinnipedia Otarii-dae) Atlacircntica 2111ndash119

Condy PR (1978) Distribution abundance and annual cycle of fur seals(Arctocephalus spp) on the Prince Edward Islands S Afr J WildlRes 8159ndash168

David JHM Salmon L (2003) Records of the subantarctic fur seal fromRodriguez and Mauritius Indian Ocean Afr J Mar Sci 25403ndash405 doi10298918142320309504029

David JHM Mercer J Hunter K (1993) A vagrant Subantarctic fur sealArctocephalus tropicalis found in the Cormores S Afr J Zool2861ndash62

de Bruyn PJN Tosh CA Oosthuizen WC Bester MN Arnould JPY(2009) Bathymetry and frontal system interactions inXuence sea-sonal foraging movements of lactating Subantarctic fur seals fromMarion Island Mar Ecol Prog Ser 394263ndash276 doi103354meps08292

Fabiani A Hoelzel AR Galimbert F Muelbert MMC (2003) Long-range paternal gene Xow in the Southern Elephant Seal Science299676 doi101126science2995607676

Ferreira JM de Oliveira RL Wynen L Bester M Guinet C Moraes-Barros N Moreno IB Muelbert MMC Siciliano S Ott PH Morg-ante JS (2008) Multiple origins of vagrant Subantarctic fur sealsa long journey to the Brazilian coast detected by molecular mark-ers Polar Biol 31303ndash308 doi101007s00300-007-0358-z

Fiedler PC (2002) Environmental change in the eastern tropical PaciWcOcean a review of ENSO and decadal variability Mar Ecol ProgSer 244265ndash283 doi103354meps244265

Gales NJ Coughran DK Queale LF (1992) Records of subantarctic furseal Arctocephalus tropicalis in Australia Aust Mammal 15135ndash138

Garrigue C Ross GJB (1996) A record of a subantarctic fur sealArctocephalus tropicalis from Madagascar Indian Ocean MarMamm Sci 12624ndash627

Georges JY Bonadonna F Guinet C (2000) Foraging habitat anddiving activity of lactating subantarctic fur seals in relation to seasurface temperatures on Amsterdam Island Mar Ecol Prog Ser196291ndash304

123

Polar Biol (2012) 35469ndash473 473

Authors personal copy

Goldsworthy SD Shaughnessy PD (1989) Subantarctic fur seal Arcto-cephalus tropicalis at Heard Island Polar Biol 9337ndash339doi101007BF00287434

Goldsworthy SD Boness DJ Fleischer RC (1999) Mate choice amongsympatric fur seals female preference for con-phenotypic malesBehav Ecol Sociobiol 45253ndash267

Goldsworthy SD McKenzie J Page B Lancaster ML Shauhnessy PDWynen LP Robinson SA Peters KJ Baylis AMM McIntosh RR(2009) Fur seals at Macquarie Island post-sealing colonisationtrends in abundance and hybridisation of three species Polar Biol321473ndash1486 doi101007s00300-009-0645-y

Gonzaacutelez JC Saralegui A Gonzaacutelez EM Vaz-Ferreira R (1994) Lapresencia de Arctocephalus tropicalis (Gray 1872) (MammaliaCarniacutevora Otariidae) en Uruguay Comunicacotildees do Museu deCiencia y Tecnologia PUCRS Ser Zool (Porto Alegre) 7205ndash210

Guinet C Jouventin P Georges J-Y (1994) Long term populationchanges of fur seals Arctocephalus gazella and Arctocephalustropicalis on Subantarctic (Crozet) and subtropical (St Paul andAmsterdam) Islands and their possible relationship to El-Nintildeosouthern oscillation Antarct Sci 6473ndash478

Hare SR Mantua NJ (2000) Empirical evidence for North PaciWcregime shifts in 1977 and 1989 Prog Oceanogr 47103ndash146

Hofmeyr GJG Amir OA (2010) Vagrant Subantarctic fur seal on thecoast of Tanzania Afr Zool 45144ndash146 doi1033770040450112

Hofmeyr GJG Bester MN Makhado AB Pistorius PA (2006a) Popu-lation changes in Subantarctic and Antarctic fur seals at MarionIsland S Afr J Wildl Res 3655ndash68

Hofmeyr GJG Kirkman SP Bester MN (2006b) Vagrant Subantarcticfur seals at Bouvetoslashya Afr Zool 41145ndash146 doi1033771562-7020(2006)41[145VSFSAB]20CO2

Kerley GIH (1983) Relative population sizes and trends and hibridisa-tion of fur seals Arctocephalus tropicalis and A gazella at thePrince Edward Islands Southern Ocean S Afr J Zool 18388ndash392

Kingston JJ Gwillian J (2007) Hybridization between two sympatri-cally breeding species of fur seal at Icircles Crozet revealed by geneticanalysis Conserv Genet 81133ndash1145 doi101007s10592-006-9269-8

Lancaster ML Gemmell NJ Negro S Goldsworthy S Sunnucks P(2006) Meacutenage agrave trios on Macquarie Island hybridization amongthree species of fur seal (Arctocephalus spp) following historicalpopulation extinction Mol Ecol 153681ndash3692 doi 101111j1365-294X200603041x

Lea MA Guinet C Cherel Y Duhamel G Dubroca L Pruvost P Hin-dell M (2006) Impacts of climatic anomalies on provisioningstrategies of a Southern Ocean predator Mar Ecol Prog Ser31077ndash94

Mawson PR Coughran PK (1999) Records of sick injured and deadpinnipeds in Western Australia 1980ndash1996 JRSWA 82121ndash128

Meyer WM Walker BG Holt RS (1996) Antarctic fur seal abundanceand distribution in the South Shetland Islands 1996 In Martin J(ed) AMLR 199596 Field Season Report Administrative ReportLJ-96-15 Southwest Fisheries Science Center NOAANMFSLa Jolla CA 92037

Naya DE Achaval F (2006) Nuevos registros de especies pococomunes de Pinnipedia y primer registro de Actocephalus gazella(Peters 1875) (Pinnipedia Otariidae) para el Uruguay Bol SocZool Uruguay 1523ndash27

Oliveira LR Zerbini A Auricchio P (2001) Um possiacutevel caso deagressatildeo em Arctocephalus tropicalis (Carnivora Otariidae) comcomentaacuterios sobre a conservaccedilatildeo de piniacutepedes no litoral do BrasilPublicaccedilotildees Avulsas do Instituto Pau Brasil 411ndash20

Payne MR (1979) Fur seals Arctocephalus tropicalis and A gazellacrossing the Antarctic Convergence at South Georgia Mamm4393ndash98

Pinedo MC (1990) Ocorrecircncia de Piniacutepedes na costa brasileira Garciade Orta Seacuter Zool 1537ndash48

Reisinger RR Bester MN (2010) Long distance breeding dispersal ofa southern elephant seal Polar Biol 331289ndash1291 doi101007s00300-010-0830-z

Robinson SA Goldsworthy SG Van den HoV J Hindell MA (2002)The foraging ecology of two sympatric fur seal species Arcto-cephalus gazella and Arctocephalus tropicalis at MacquarieIsland during the austral summer Mar Freshw Res 531071ndash1082

Shaughnessy PD Burton HR (1986) Fur seal Arctocephalus spp AtMawson station Antarctica and in the Southern Ocean Polar Rec2379ndash81

Shaughnessy PD Ross JB (1980) Records of the Subantarctic fur seal(Arctocephalus tropicalis) from South Africa with notes on itsbiology and some observations of captive animals Ann South AfrMus 8271ndash89

Taylor R (1990) Records of subantarctic fur seals in New Zealand NZJ Mar Freshw Res 24499ndash502

Torres D (1985) Presencia del lobo Wno sudamericano (Arctocephalusaustralis) en el norte de Chile como consecuencia de El Nintildeo198283 Invest Pesq (Chile) 32225ndash233

Torres D Aguayo-Lobo A (1984) Presence of Arctocephalus tropical-is (Gray 1872) at the Juan Fernaacutendez Archipelago Chile ActaZoologica Fennica 172133ndash134

Torres D Guerra C Caacuterdenas JC (1984) Primeros registros de Arcto-cephalus gazella y nuevos hallazgos de Arctocephalus tropicalisy Leptonychotes weddelli en el archipieacutelago de Juan FernaacutendezSer Cient INACH 31115ndash148

Trillmich F Limberger D (1985) Drastic eVects of El Nintildeo on Galapa-gos pinnipeds Oecologia (Berlin) 6719ndash22

Weimerskirch H Inchausti P Guinet C Barbraud C (2003) Trends inbird and seal populations as indicators of a system shift in theSouthern Ocean Antarct Sci 15249ndash256

Wynen LP Goldsworthy SD Guinet C Bester MN Boyd IL Gjertz IHofmeyr GJG White RWG Slade PR (2000) Postsealing geneticvariation and population structure of two species of fur seal (Arc-tocephalus gazella and A tropicalis) Mol Ecol 9299ndash314doi101046j1365-294x200000856x

Ximeacutenez A (1980) Sobre la presencia de Arctocephalus tropicalis(Gray 1782) en el nordeste de Brasil (Mammalia Arctocephali-nae) Rev Bras Biol 40591ndash592

Zanre R Bester MN (2011) Vagrant subantarctic fur seal in the May-umba National Park Gabon Afr J 46185ndash187 doi1033770040460111

123