In addition to the polar bear, the following marine mammal species can regularly be found in the Beaufort Sea off the coast of the refuge: beluga whale, bearded seal, ringed seal, spotted seal, and the endangered bowhead whale. Additionally, four species may rarely appear: gray whale, orca, walrus and harbor porpoise.

Should oil or toxic spills occur in or near the sea these can be particularly harmful because oil remains toxic for longer periods in the cold waters and it concentrates in open waters in the sea ice and breathing holes where animals surface and congregate. Oil spills remain toxic longer and are more difficult (perhaps impossible) to clean up because it gets trapped in the ice and takes longer to breakdown in the cold.

Impacts may be more severe on marine mammals because they bio-accumulate many of the toxic chemicals in their bodies, resulting in the release of more concentrated doses further along the food chain when they are preyed or scavenged upon. Marine mammals are also affected by noises from industrial activity may affect marine mammal navigation, social interactions, prey capture, and predator avoidance.

One marine mammal species – the endangered bowhead whale – would be particularly vulnerable because it is still recovering from the brink of extinction. Just 7,800 animals, the majority of the world's stock, now inhabit the Western arctic. This entire population migrates together, so a spill in their path would be disastrous. Oil damages their eyes, clogs their sensory hairs and impairs their breathing. Finally, noise from drilling and ice breakers disorients whales, interferes with motion, nursing and cow/calf bonds, and masks whale calls.

Read more about these animals with our Marine Mammals near the Arctic National Wildlife Refuge fact sheet.