Haliotis rufescens

Red abalone is the largest and most common abalone found in the northern part of the state of California, United States. Red abalone live in rocky areas with kelp. They feed on the kelp species that grow in their home range, including giant kelp (Macrocystis pyrifera), feather boa kelp (Egregia menziesii), and bull kelp (Nereocystis luetkeana). Juveniles eat coralline algae, bacteria, and diatoms. They are found from the intertidal zone to water more than 180 m (590 ft) deep, but are most common between 6 and 40 m (20 and 131 ft). The red abalone's shell length can reach a maximum of 31 cm (12 in), making it the largest species of abalone in the world. The shell is large, thick, dome-shaped, and usually covered with barnacles, vegetation, or other marine growth making the color and shell sculpture difficult to determine.