Scientists in California are testing the hearing of polar bears to try to find out whether the noises associated with melting Arctic ice could affect their ability to survive.
In the wild, polar bears live in one of the quietest places on Earth. For much of the time, the Arctic is a bitterly cold, silent world.
But global warming is changing that. Ice, which is crucial to the bears’ survival, is disappearing and people are moving in.
“We’re expecting industrial activity, shipping, recreation, all of those human activities to increase in the Arctic,” says Dr Ann Bowles, a senior research scientist at Hubbs-Seaworld Research Institute in San Diego.
“We’re going to be bringing noise and activity much closer to these guys. What we’re trying to do is help to protect the bears during this period of transition,” she says.