Fish & Water - Sounds Wild
Sea Urchin

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Urchins

It's a minus tide on a beautiful summer morning, and some kids are tide pooling. They've found a green sea urchin, covered with spines. They handle it carefully for a moment and gently return it to the pool. Urchins are familiar to beachcombers as hollow, round white shells. Living urchins are covered with bony spines that fall off shortly after they die. Alaska is home to both green and red sea urchins.

Urchins are echinoderms, and are related to sand dollars and sea stars. The name urchin is an old word for hedgehog, and sea urchins are spiny like hedgehogs. Urchins feed on algae like kelp, and are in turn eaten by sea otters, star fish, and fish like triggerfish and wolf eels that can deal with the spines and open their shells. Alaska's red and green sea urchins have short spines, but some tropical sea urchins have venomous spines.

Urchin roe is also popular in Asia, and is known as uni (oooni). Red sea urchins are harvested by hand by divers in southern Southeast Alaska, and green sea urchins are harvested around Kodiak Island. Urchins are monitored by Fish and Game in several dozen areas in Southeast to insure that the harvest is sustainable

Although urchins in Alaska only measure a few inches across, they are surprisingly long lived. Growth rings laid down annually allow researchers to determine the age of the urchins, and the oldest green sea urchin harvested was 16 years old. A red sea urchin, also from southern southeast Alaska, was 32 years old.