Because polar bears are entirely dependent upon the sea ice for their survival, any observed and projected reductions in preferred sea ice habitats can only result in declines. (dotearth.blogs.nytimes.com)
Because global climate models predict critical sea ice habitat will disappear as CO2 concentrations rise, they argue the seals are ultimately endangered. (landscapesandcycles.net)
The most significant threats to arctic marine mammals comprise loss of sea ice habitat and its associated highly productive food web along with the increase in anthropogenic activities at high latitudes (Ragen et al. 2008). (link.springer.com)