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The Northern abalone is a gastropod with a flattened, ear-shaped shell with a slightly scalloped edge with 3 to 6 respiratory holes; the adult shell is approximately 4 inches long, but some specimens grow as large as 6 inches. The interior of the shell is iridescent, and the epipodium (the visible lobe of the animal's foot) is lacy and green-brown in color. Tentacles surrounding the foot and extending out of the shell sense food and predators.
Northern abalone are found in kelp beds along well-exposed outer coasts from Sitka, Alaska south to Point Conception, California. The preferred habitat is in the rocky tidal or subtidal area near kelp to 30 feet (9m) in depth, but they can be found as deep as 330 feet (100m).
Abalone are herbivores, and live mainly on kelp and other sea plants.
The Northern abalone's population has declined, particularly off the California coast, due to human harvesting, predators and disease. Because of concerns about its status the Northern Abalone is a U.S. National Marine Fisheries Service Species of Concern, and commercial harvest is no longer permitted along the shores of Oregon, Washington, Canada and Alaska.