The Fraying Arctic Food Web
Arctic animals are extremophiles -- they're specialists adapted to thrive at temperatures that stretch the very limits of biological tolerance. It's a club with few members. Species diversity is low. As a result, Arctic food webs are relatively simple. And in the age of climate change, that's not a good thing to be, because when one organism is depleted due to shifting environmental conditions, it has a ripple effect on everything else in the web (see our Spring 2011 cover story Arctic Fever).
In this depiction of the Arctic food web, click an animal to see it disappear -- and then watch what happens to the rest of the web. (Hint: Starting with the smallest animals can result in the biggest changes.)
They subsist almost entirely on seals. No other food comes close to providing the massive amounts of fat the bear needs to survive the Arctic's extreme cold.
They prefer to consume Arctic cod for its high fat and calorie content. As sea ice and snow cover disappear, seals have fewer places to rest and raise their young.
One of the only fish that can survive the extreme cold, thanks to blood like antifreeze and high fat content. But as the waters warm, other fish are taking its territory.
Microscope organisms form the base of the Arctic food web. Ice is the equivalent of their soil, but changing marine chemistry is stunting their growth.
Networks of needle-like cracks and tubes in Arctic ice allow hundreds of species of bacteria, fungi, and other single- and multi-cellular organisms to thrive.
Amphipods and other shelled organisms feed everything from birds to whales to walruses to seals. As marine waters acidify, their shells may dissolve.