They prefer eating pieces of kelp, a large brown algae. However, they may also feed on phytoplankton and diatoms if there is nothing else to eat. They use a radula, an organ with many sharp teeth, in order to munch down their salty meal. Adult abalone also have to be wary of predators such as octopus, crab, lobsters, seastars, and otters. Abalone found in a sea otter range are often smaller, on average, and more restricted to cracks and crevices.
Abalone are slow growers and long-lived.
In addition, their recruitment rates are often very unpredictable. Unfortunately, these characteristics make abalone very susceptible to over-harvesting. The next section describes the rapid demise of the pinto abalone population, and of populations of abalone around the world. The History Abalone has been harvested for hundreds of years. 30 A.D. The northern abalone has been used by the First Nations of the northwest coast for food, and the nacre used for jewelry and decoration.