ANCHORAGE, Alaska — A lawsuit making its way through federal court in Alaska will decide whether Pacific walruses should be listed as a threatened species, giving them additional protections. Walruses use sea ice for giving birth, nursing and resting between dives for food but the amount of ice over several decades has steadily declined because of climate warming. Walruses by late summer come ashore in Alaska and Russia because ice recedes beyond the shallow continental shelf where walruses can dive for clams. The U.S. Fish and Wildlife Service says walruses are adapting to less ice and no one has proven that they need added protection. The Center for Biological Diversity is fighting the decision. Climate science director Shaye Wolf says walruses on shores have suffered stampede deaths and are pushed from feeding areas.