Dispersal and dispersion of southern elephant seals in the Kerguelen province, Southern Ocean

• Published in: Antarctic Science
• Main Authors: Oosthuizen, Wessel Christiaan, Bester, Marthan Nieuwoudt, Tosh, Cheryl A., Guinet, Christophe, Besson, Dominique, De Bruyn, P.J. Nico
• Format: Article in Journal/Newspaper
• Language: English
• Published: Cambridge University Press 2011
• Subjects: Gene flow; Iles Crozet; Iles Kerguelen; Mark-resighting; Metapopulation; Migration; Mirounga leonina; Marion Island; Southern elephant seal > Kerguelen Islands; Indian; Kerguelen; Kerguelen Islands; Southern Ocean; Antarctic Science; Elephant Seal; Elephant Seals; Southern Elephant Seal; Southern Elephant Seals
• Online Access: http://hdl.handle.net/2263/17773; https://doi.org/10.1017/S0954102011000447

Southern elephant seals Mirounga leonina within the Kerguelen province disperse between Marion Island (MI), Iles Crozet (IC) and Iles Kerguelen (IK) despite the high site fidelity characteristic of this species. From 1987–2002, 199 IC individuals, or 11.63% of the tagged population there, were resighted at MI. Resights of IC seals at MI peaked during the juvenile moult and seals aged 0–2 represent 66% of all resights made. Equal numbers of male and female seals (all age classes) were dispersing. Dispersing breeding females (n=22, on 33 occasions) outnumbered dispersing breeding males (n=6, on 16 occasions), after initially emigrating from IC to MI as juvenile seals (natal dispersal). Greater male-mediated gene flow was ultimately attained due to the polygynous mating system and some extremely successful males. Of 132 seals fitted with satellite-relay data loggers at MI, six hauled out at IC and three at IK. Two of the seals which migrated to IC were born at MI; all others were unmarked males likely to be native to IC or IK. Dispersal should ideally be considered when assessing vital rates for southern Indian Ocean elephant seal populations. The Department of Science and Technology, through the National Research Foundation (NRF), provided financial support. WCO received financial support from a NRF Grantholder-linked bursary within the project ‘‘Conservation of Seabirds, Shorebirds and Seals’’ led by L. Underhill of the Animal Demography Unit, Department of Zoology, University of Cape Town. http://journals.cambridge.org/action/displayJournal?jid=ans ab2012