Although global warming is still often a controversial topic, there is no denying its effects, particularly among animal populations like walruses. Now, due to global warming and the melting of sea ice, 35,000 of these creatures are gathering on a shore near Anchorage, Alaska, because they have nowhere else to go.

Sea ice offers walruses a rest between hunting. Unlike other sea mammals, they cannot spend as much time in the ocean. They rely on sea ice for respite, but with sea ice shrinking, these walruses rely on land instead, resulting in crowding and stampeding.

The National Oceanic and Atmospheric Administration recently reported this large gathering of walruses near Anchorage after doing an aerial survey of the area.

Most of these walruses, from the Pacific Ocean, spend winter in the Bering Sea. There, sea ice is used for giving birth, as well as for diving areas that allows them to hunt worms and clams.

During summer, the sea ice shrinks in that area, so the walruses move north. However, it's shrunk so much recently that it's almost non-existent, and where there is ice, it's no longer shallow enough for walruses to dive to the bottom for hunting.

"The walruses are telling us what the polar bears have told us and what many indigenous people have told us," says Margaret Williams, managing director of the World Wildlife Fund's Arctic program. "And that is that the Arctic environment is changing extremely rapidly and it is time for the rest of the world to take notice and also to take action to address the root causes of climate change."

Scientists first noted these large gatherings of walruses in 2007, but last year was the first year that the numbers were so large, at 30,000. This year, there are even more, suggesting that this could be a serious ongoing problem.

Currently, the temperature of the sea surface in the area is over 5 degrees Fahrenheit higher than normal.

"We are witnessing a slow-motion catastrophe in the Arctic," says Lou Leonard, vice president for climate change at the World Wildlife Fund. "As this ice dwindles, the Arctic will experience some of the most dramatic changes our generation has ever witnessed."

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