Loss of sea ice
Walruses feed by diving in shallow waters for food from the seabed, resting in between dives on sea ice. They even leave their young on the sea ice whilst they search for the food. This is known as a haul out.
Warming temperatures in the arctic have seen a decline in sea ice – in fact the arctic is warming at twice the rate of anywhere else on Earth.
This decline in sea ice leads walruses to rest or leave their young on the shore instead, before travelling further and diving deeper to get food.
Not only does this mean that their young are going unprotected for longer, adult walruses are getting more tired in between dives for food.
Less sea ice also means that more vessels are coming into walrus habitats.
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Noise pollution
Walruses are spooked easily, not only as vessels pass through the remaining sea ice, but also underwater. More ships mean a rise in underwater noise, created by bubbles from ship propellers. This makes it much harder for walruses and other underwater creatures to use sound to locate food.
When vessels do pass through where walruses haul out, they can scare the walruses, leading to stampedes. This leads to crushes, and often it is the calves that are killed.
Noise pollution comes alongside oil and chemical spills in the water from ships, as well as ongoing plastic pollution.
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Overfishing
Once a walrus has travelled away from the shore, without sea ice to rest on, it might still struggle to find any food. Overfishing means reduced food, and the food there is is subject to more competition.
The Walrus is a keystone species in Arctic marine ecosystems and its way of life and of finding food is changing in the face of global warming.
All of this has seen them listed as vulnerable on the IUCN red list.