Chitons: Polyplacophora

Physical characteristics: This is the largest chiton in the world, measuring up to 13 inches (330 millimeters) in length and 5 inches (130 millimeters) across. It resembles a brick-red meatloaf. Its large size and color distinguish this species from other chitons. The leathery and reddish mantle wraps around the entire body and hides all of the valves. It is covered with bundles of tiny spines.

Geographic range: Gumboot chitons are found from the Aleutian Islands in Alaska, south to San Miguel and San Nicolas Islands off the coast of southern California. They are also found in northern Hokkaido Island, Japan, and the Kurile Islands in Kamchatka, Russia.

Habitat: This species lives on rocky shorelines and soft bottoms in protected habitats near deep channels at depths of 70 feet (21.3 meters).

Diet: They eat several kinds of algae, including giant kelp, sea lettuce, and red algae.

This is the largest chiton in the world, measuring up to 13 inches (330 millimeters) in length and 5 inches (130 millimeters) across. (Al Lowry/Photo Researchers, Inc.)

Behavior and reproduction: This species grows very slowly and lives as long as twenty years. They have a weak grip and often fall from their rocks at low tide. They do not live in groups and move very slowly. Captured individuals have remained within 65.6 feet (20 meters) of their release point, even after two years.

California populations reproduce between March and May. The reddish eggs are laid in jelly-like spiral strings measuring up to 3.3 feet (1 meter) in length. The strings are broken up into smaller pieces by ocean waves. The eggs hatch about five days after they are fertilized. The free-swimming larval stage lasts about twenty hours. Then they settle to the bottom and develop into young chitons.

Gumboot chitons and people: This species was eaten by Native Americans living along the Pacific Coast of North America.

Conservation status: Gumboot chitons are not considered threatened or endangered. ∎