Diseases and parasites of antarctic and sub-antarctic seals

Antarctic phocids (or true seals) include the crabeater seal Lobodon carcinophagus, the Ross seal Ommatophoca rossii, leopard seal Hydrurga leptonyx, the Weddell seal Leptonychotes weddellii and the southern elephant seal Mirounga leonina. While the first three species breed and spend most of their lives in the pack-ice, the fourth breeds on the coastal fast-ice of the Antarctic and makes foraging trips from there that may extend into the pack-ice. Leopard seals also exploit continental penguin colonies in summer. The southern elephant seal breeds predominantly on sub-Antarctic islands (some breeding occurs on the Antarctic Peninsula and Valdes Peninsula, Argentina) and some bachelor males haul out to moult in summer on the Antarctic continent. All (although more rarely the Ross seal) have been recorded as vagrants from the southern continents. All otarid (or eared) seals, including the Antarctic fur seals Arctocephalus gazelle, breed north of 65°S. Sub-Antarctic fur seals A. tropicalis breed on sub-Antarctic islands north of the Antarctic Convergence and other otarids may breed on sub-Antarctic islands (e.g. the New Zealand fur seal A. forsteri) as well as further north. Opportunities exist for interaction and disease transmission between the pinnipeds, although limited by ecological niches, behaviour, population homogeneity and density.