Haliotis rufescens

Haliotis rufescens, commonly known as the red abalone, is the largest species of abalone found along the Pacific coast of North America. These marine gastropod mollusks inhabit rocky intertidal and subtidal zones from Oregon to Baja California, Mexico, typically at depths ranging from the low tide zone to approximately 20 meters. Red abalone are characterized by their large, ear-shaped shells that can reach up to 30 centimeters in length, with a distinctive reddish-brown exterior and iridescent interior. They feed primarily on kelp and other marine algae, playing an important ecological role in nearshore marine ecosystems. The species has experienced severe population declines since the 1990s, leading to its classification as Critically Endangered. Primary threats include withering syndrome, a bacterial disease that has devastated populations, ocean warming and acidification associated with climate change, and historical overharvesting. The collapse of kelp forests due to sea urchin population explosions has also reduced available food sources. Conservation efforts include captive breeding programs, habitat restoration initiatives focused on kelp forest recovery, and strict fishing regulations. California has implemented a complete moratorium on recreational and commercial red abalone fishing to allow populations to recover. Research continues into disease resistance, genetic diversity, and optimal restoration techniques to support the species' recovery in its native range.