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The Prince Edward Islands in the southern Indian Ocean form the first sub-Antarctic Ramsar Wetland Site of International Importance in the sub-Antarctic, designated by South Africa on 22 May 2007 as No. 1688.  The larger of the two islands, Marion, supports a weather station with a team that is relieved annually.  The smaller island, also named Prince Edward, is uninhabited and rarely visited, and then only under strict environmental conditions to avoid introducing new alien species.

From 14-19 April 2010 a party of six researchers visited Prince Edward Island to undertake research and surveys on birds, seals, invertebrates and historical sites from the sealing era.

As part of the bird work, a near-complete count was made of brooding Wandering Albatrosses Diomedea exulans.  The two Prince Edward Islands support approximately 44% of this globally threatened species, at risk from being drowned on longline fishing hooks.  A single locality on Prince Edward Island, Albatross Valley, supported 1000 to 1200 annually breeding pairs in the 2002 and 2009 breeding seasons, respectively, representing 12-14% of the world annual breeding population of 8500 pairs.  Nearly all these nests can be viewed from a single vantage spot: surely one of the most impressive avian spectacles in the world.

 

On 15 April, 1286 occupied nests were counted in Albatross Valley, most containing either chicks on their own, or being brooded by adults.  The scene looked idyllic and no different to what it must have looked before the island's discovery at the end of the 18th century.  But the presence of a longline fishing hook next to an occupied nest elsewhere on the island showed that Prince Edward's Wanderers remain at risk: as does the species worldwide.

While on the island efforts were made to fill in the gaps of a survey commenced in 2008 of the number of White-chinned Petrels Procellaria aequinoctialis burrows.  Once added to a similar survey recently conducted on Marion Island, the Prince Edward Islands will be one of the few breeding localities for this ACAP-listed burrowing petrel where a better than an order-of-magnitude estimate of its population size will be available.

References:

Ryan, P.G., Cooper, J., Dyer, B.M., Underhill, L.G., Crawford, R.J.M. & Bester, M.N. 2003. Counts of surface-nesting seabirds breeding at sub-Antarctic Prince Edward Island, summer 2001/02. African Journal of Marine Science 25: 441-451.

Ryan, P.G., Jones, M.G.W. Dyer,B.M., Upfold, L. & Crawford, R.J.M. 2009.  Recent population estimates and trends in numbers of albatrosses and giant petrels breeding at the sub-Antarctic Prince Edward Islands.  African Journal of Marine Science 31: 409-417.

John Cooper, Stellenbosch University and Bruce Dyer, Azwianewi Makhado and Leshia Upfold, Marine & Coastal Management, Department of Environmental Affairs, 21 April 2010.