The Pacific walrus faces warming temperatures and a loss of its habitat. These walruses depend on sea ice to birth and take care of their young, but melting glaciers means that they have to venture onto land for food, which can often lead to overcrowding and stampedes, according to the National Wildlife Federation. While the current size of the walrus population is unknown, it was last estimated to be about 129,000 in a 2006 survey.
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