Abalone

Natural history

Like other gastropods, the abalone shell is part of its body. It is considered an exoskeleton, protecting it during low tides and from predators and other bodily harm. The shell grows as the abalone grows. Abalone shells are made of calcium carbonate. The innermost layer is made of a specific type of calcium carbonate called nacre, or mother-of-pearl, which in the past was widely used for jewelry and other decorative arts.

Abalone are mostly sedentary and exceptionally strong. They cling to rocks while waiting for a piece of kelp to drift nearby. The abalone clamps down on the kelp with its foot and then munches on algae with its radula—a tongue-like band with many small teeth.

Conservation

Abundant in the early 20th century, abalone once supported huge commercial and sport fisheries. Due to overfishing and disease, today's abalone faces extinction—both white and black abalone are listed as endangered under the Endangered Species Act. To protect wild abalone, strict fishing laws have been enacted. Farmed abalone may offer a sustainable alternative.

Cool facts

• If an abalone is touched by a sea star, it twists its shell violently to dislodge the intruder and then gallops off—abalone style.
• An abalone's blood is blue-green. Since its blood lacks sufficient blood-clotting mechanisms, an injury can be fatal.
• Poaching abalone is a risky enterprise. In California, heavy fines and jail time are likely for poaching abalone.
• Abalone produce pearls by secreting a shell over parasites or irritating particles of gravel that lodge in their flesh. Some abalone farmers, hoping to harvest pearls at a later date, are now seeding abalone.