News

Elephant seal travelling over 8,000 km to mate

(31 January 2003)

Researchers at the University of Durham have identified a male southern elephant seal who was born in the South Pacific and travelled over 8,000 km to mate and reproduce on the Falkland Islands.

This is the first demonstration of long-range movement of genes in this species. The research paper is published in the prestigious journal of the American Association for the Advancement of Science today (31 January 2003).

The elephant seal is a highly polygynous species and can father many offspring. This means that this rare dispersal event has the potential to spread significant variation. Although theoretical expectations suggest that males should be the primary dispersers in mammalian species, it is difficult to identify actual genetic dispersal events such as this one. In this case, the seal whose nickname is Blob fathered at least 19 offspring in the Falklands.

The findings of the research also show that there is continuing gene flow between two populations that are on opposite ends of the species range, and between which there is no evidence for the mixing of females.

Dr Rus Hoelzel from the Biology Department at Durham University commented, "This male illustrates the potential influence long-range dispersers could have in polygynous species to reduce differentiation between distant populations. The impact on patterns of genetic diversity across the species range will depend on how common such events are, that is, on the balance between migration rate and genetic drift."

For further information, please contact:
Dr Rus Hoelzel, Department of Biological Sciences. Tel: 0191 374 7745

Dionne Hamil, Public Relations. Tel: 0191 374 1805

For a copy of the full paper, please contact Lisa Onaga by email on scipak@aaas.org.