This biome is an ocean shore
environment. The animals that live here find their food in the
ocean. Some of the top predators go onto the land to rest or
reproduce, but the food that they eat is in the icy waters.
The primary producers are microscopic
in size. Tiny diatoms, crustaceans, and protozoans live here.
Oceanic upwelling brings nutrients from the bottom of the sea,
and these microscopic creatures thrive.
The primary consumers, such
as small fishes and squid, eat these tiny lifeforms.
The most important of the primary consumers are krill, small,
shrimp-like animals that swarm in great numbers. Krill are a
very important part of the food chain in the ocean. During the
recent El Nino seasons their numbers were reduced by environmental
changes in the water, and many larger animals starved.
The secondary consumers include
the huge blue and humpback whales, who feed on krill. Seals and
many kinds of fishes also feed on krill and the smaller fish.
Many kinds of sea birds utilize these resources, and, in the
Antarctic, penguins also feed on them.
The top predators in
this food chain are killer whales. (Polar bears occupy this position
in the arctic north) These are large, powerful animals, well
adapted to their niche in a cold, demanding environment. They
eat whatever they can catch, and prey mainly on penguins and
seals.
This food chain is an interesting
one. It is so obviously a chain of meat eaters above an enormous
number of tiny primary producers. It seems at once robust and
vulnerable, and the vitality of the animals stands in stark contrast
to the rigors of their environment.
© Elizabeth Anne
Viau, 1999. This material may be used freely for instructional
purposes but not sold for a price beyond the cost of reproduction.
Please inform the author if you use it at eviau@earthlink.net
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