Large Predators

Large Arctic predators are dependent on ice sheets for hunting and resting. Loss of ice is reducing the areas in which animals such as polar bears can hunt. Reduction of these large predators increases the numbers of species on which they prey.

Caribou

Caribou are increasing in numbers due to reduction in predators. They are also benefiting from the increase food production due to warmer temperatures and longer growing seasons.

Plant Growth

Shrubs are growing more. But these plants are competing with lichens, which provide a winter food source for caribou.

Plankton

Arctic plankton are very susceptible to changes in the environment. Melt water from glaciers is adding freshwater to the system, changing salinity levels. Plankton also do poorly in warmer waters. These small plankton are at the very bottom of the food chain, feeding fish and other small sea creatures, which in turn become food for larger predators.

Change of Landscape

Animals have fewer hunting grounds as the ice melts. Warming also produces more precipitation. And food becomes unattainable due to increasing snowfall, which blocks the paths used to access it.

Source:

Ecological Impacts - Alaska and the Arctic

Arctic Plankton Sing the Global Warming Blues