Melting Sea Ice Spells Serious Consequences for Arctic Wildlife

As Arctic sea ice continues to shrink, wildlife is facing some serious and widespread consequences. Now, scientists have examined the relationships among algae, plankton, whales and terrestrial animals to see exactly what these impacts might be--and have made some disturbing findings.

Each year, sea ice continues to decline. In fact, Arctic sea ice has disappeared by more than 86,000 square kilometers, which is an area slightly larger than South Carolina, each year. Future models also predict that this rate could accelerate as the reflective white surface of snow and ice gives way to darker ocean waters, which absorbs heat more readily.

So what might happen to wildlife if melting continues to occur? There could be a domino effect through the food chain. Sea-ice algae and sub-ice plankton, which together account for about 57 percent of the total annual biological production in the Arctic Ocean, already are being immediately affected by sea ice melting; ice loss triggers a significant change in the blooming times of these organisms, for example. In addition, land adjacent to areas of sea-ice loss will experience significant surface warming inland from the coastline. This will affect soil conditions and plant growth.

So what sort of chain reaction can we expect to occur? Ocean-dwelling animals will be affected by disrupted food sources and terrestrial animals may also be affected. Temperature changes will affect plant communities inland, which could affect creatures such as caribou.

In addition, populations of animals could become even more isolated with the lack of sea ice. Communities of arctic foxes and wolves, for example, are currently isolated only during the summer. Yet a longer period of the year without ice could lead to a decline in crossbreeding.

While there could be isolation in some species, though, there would be more intermingling in others. Ice can act as a barrier for polar and grizzly bears, which means that a lack of sea ice could promote more encounters between the two species.

"We know that, for some species, sea ice acts as a barrier to intermixing," said Eric Post, one of the researchers, in a news release. "So for these species, ice loss and a lengthening of the ice-free season likely will increase population mixing, reducing genetic differentiation." In fact, scientists have already polar and grizzly bear hybrids since polar bears are spending more time on land.

The findings reveal a little bit more about how sea ice loss could affect wildlife in the future. More specifically, the research could show conservationists where to target their efforts so that they can be more effective.

The findings are published in the journal Science.