Whales in a changing Arctic: A call for action

The three whales that are endemic to the Arctic—bowhead whales, white whales (or belugas) and narwhal—have, over evolutionary time, become high-latitude specialists that live in close association with sea ice. Thus, it is no surprise that climate change is a cause for concern for their well-being.

The Arctic is warming four times faster than the global average. Air and water temperatures are increasing, glaciers are melting and retracting onto land, and sea ice is declining rapidly. Current trends suggest that an ice-free Arctic (in summer) is possible before 2050. What will the consequences be for ice-dependent whales?

The short answer is that the consequences are likely to be many—and most will not be good. Climate change is causing both direct and indirect deterioration of ice-whale habitats. These whales depend on vast areas of sea ice for protection from storms and predators.

In the past, the sea ice edges that sweep north in the spring over shallow Arctic seas induced upwelling (the movement of nutrients from deeper waters to the surface), boosting the growth of plants and algae and, in turn, making food more available and easier for whales to find.  These areas were also free from competition with other species that cannot cope with ice cover, and the sea ice curbed the whales’ contact with southerly species that are more exposed to diseases. The presence of Arctic sea ice across vast areas for thousands of years also limited a host of human activities that readily take place in open oceans.

But climate change is removing many of these protections, generating new challenges for Arctic-endemic whales, including risks associated with ocean noise, oil spills, pollutants, and ship strikes in an Arctic with more ship traffic. Competition for food—with both human fisheries and southerly species moving North—and declines in the availability of traditional Arctic prey species are adding to the risks.

This issue of The Circle addresses some of these challenges for Arctic-endemic cetaceans (along with harvest issues in Greenland) and proposes new monitoring methods and conservation actions to help mitigate the negative impacts on these whales.

We should not give up trying to slow climate change. But in the meantime, directed action to ensure that Arctic-endemic whales remain part of our future is essential. Arctic nations need to hunt responsibly and sustainably, leave enough fish and other forms of sea life to sustain Arctic species, and learn more about the ecological needs of, and key threats to, each of the three Arctic whale species so that we can take appropriate steps to protect their habitats.