Citation. Thomas, J. A.; Ferm, L. M.; Kuechle, V. B. 1987. Silence as an anti-predation strategy by Weddell seals. Antarctic Journal, pp. 232-234.   [1555  CC]

Introduction. In McMurdo Sound, Antartica, Weddell seals (Leptonychotes weddelli) return to traditional breeding colonies on shorefast ice each austral spring. This fast ice provides a stable platform, over a 2-month period, for raising pups and a fixed location for establishing underwater mating territories. However, it also may provide protection from predators, such as leopard seals (Hydrurga leptonyx) or killer whales (Orcinus orca). Weddell seals are the only marine mamal in the shorefast ice of McMurdo Sound from October through early December. When killer whales and leopard seals arrive in mid-December, they work the ice edge for available prey, especially penguins. As the fast ice breaks up, leads provide access to nearby Weddell seal colonies (Thomas et al. 1981). In late December, U.S. Coast Guard icebreakers open a lead for entry to McMurdo Station (figure 1). Killer whales and leopard seals use this large lead and its tributaries to move closer to Weddell seal colonies.

Keywords. Weddell seals, Leptonychotes weddelli, leopard seals, killer whales, anit-predation