Hudson bay ringed seal: Ecology in a warming climate

Abstract

Ringed seals (Phoca hispida) have evolved to exploit snow covered sea-ice platforms for reproduction and survival and may face critical challenges with ongoing and predicted climate change. The Hudson Bay ecosystem is already showing signs of climate warming raising concerns for the ecological, economical, and culturally-significant ringed seals of Hudson Bay. This chapter summarizes the current knowledge on ringed seals in this subarctic region, including recent findings, and presents the data in regard to current climatic changes. In Hudson Bay, sandlance (Ammodytes sp.) is a major component of ringed seal fall diet, whereas Arctic cod (Boreogadus saida) representation in the diet is trivial, contrasting results from other Arctic locations. A comparison of density and demographic parameters between the 1990s and the 2000s suggests environmental conditions in the 1990s were not favourable for ringed seals, but improved in the 2000s. A decadal cycle in ringed seal numbers and reproductive performance may relate to variations in environmental conditions, particularly changes in the sea-ice regime. However, ringed seal pups are sensitive to snow cover and ice stability for survival. Thus, a long-term decline of ringed seal fitness in response to current and projected trends in Hudson Bay environmental variables may underlie the natural cycle. Long-term demographic studies of ringed seals at the southern limit of its range are needed to comprehend ringed seal population dynamics and its interaction with environmental variables. © 2010 Springer Netherlands.