White Abalone
Haliotis sorenseni
White abalone were once common along the coasts of California, USA and Baja California, Mexico, but the population has declined rapidly. This decline was largely due to the operation of brief but intense commercial fishing in southern California during the 1970s. All abalone fisheries have been closed since 1997 but the white abalone populations have not recovered as expected due to illegal poaching, specific breeding needs, and disease.
Organizations like The National Oceanic and Atmospheric Administration (NOAA), Aquarium of the Pacific, and other partners have been working to save the white abalone from extinction. In late 2019, the fruition of the White Abalone Recovery Program was achieved when thousands of young white abalone were released to nature.
Credit: Aquarium of the Pacific/Andrew Reitsma
SPECIES IN DETAIL
White Abalone
Haliotis sorenseni
CONSERVATION STATUS: Endangered
CLIMATE CHANGE: Vulnerable
At the Aquarium
Southern California Gallery
Geographic Distribution
Historically, white abalone were found in the Pacific Ocean from Point Conception, California, USA to Punta Abreojos, Baja California, Mexico. Today there are low numbers of white abalone along the mainland coast of southern California and on offshore islands and banks. The status of the species in Mexico remains largely unknown.
Habitat
Found on rocky substrates alongside sand channels usually found at depths of 15-55 meters (50-180 feet).
Young abalone hide in rock crevices, under rocks and even under sea urchin spines. Adults are often found on rocks, closer to the sandy zone.
Sand channels are believed to help the white abalone capture algae that are often found floating between the channels.
Physical Characteristics
Marine snail with a thin, oval shell containing a row of three to five holes used to breathe, excrete waste, and reproduce. The inside of the shell is a pearly white. The epipodium (the raised ring below the shell, above the foot) is green and beige with dark brown tentacles.
The bottom of the foot is an orange muscle used to move, attach to rocks, and sense the surrounding environment. Abalone blood has no clotting ability, making it easily susceptible to mortality when nicked by divers trying to remove the animal from a rock.
Size
Up to 25.4 cm (10 inches) and between 0.5-0.9 kg (1-2 pounds).
White abalone grow 10 to 29 millimeters (0.4 to 1.1 inches) per year.
Diet
In the wild white abalone eat different types of drift algae and macroalgae, such as kelp. They use the front part of their foot to capture drift algae and bring it to their mouth. White abalone feed most actively at night.
At the Aquarium of the Pacific, white abalone may be fed kelp and other macroalgae.
Reproduction
White abalones reach sexual maturity between 4 to 6 years of age, when they are about 10 centimeters (4 inches) in size.They are broadcast spawners, releasing eggs and sperm into the water by the millions when environmental conditions are optimal. Broadcast spawning relies on other abalone being within several feet to help ensure the eggs have an opportunity to be fertilized. Embryos develop into free swimming planktonic larvae, eventually settle down to the substrate as juvenile, and grow into adults.
White abalone raised in hatcheries were found to reproduce at younger ages and smaller sizes.
Behavior
White abalone feed most actively at night, preferring low light conditions. White abalone are slow moving, which makes them highly susceptible to aggressive predators such as humans.
Adaptation
Due to overfishing within the human accessible zones, white abalone are now found living at deeper depths. Historically, they could be found as shallow as 5 meters (16 feet), but now can mostly be found at 30-60 meters (98-196 feet).
Longevity
30-40 years
Conservation
The National Oceanic and Atmospheric Administration (NOAA) in collaboration with the Aquarium of the Pacific, the UC Davis Bodega Marine Laboratory, the Bay Foundation, Paua Marine Research Group (PMRG), the California Department of Fish and Wildlife, and various other partners have been working together to help save the white abalone from extinction - this is the first time in history that this federally protected species is being released into the wild.
Special Notes
White abalone are kelp forest architects! They graze on kelp helping to promote kelp and animal diversity by clearing patches of rocky surfaces to make room for a variety of kelp species, fish, and other animals.
White abalone are forgotten treasures! There are so few white abalone in nature that the species is nearing extinction. The Aquarium of the Pacific has been working with NOAA for over 11 years on a White Abalone Recovery Program to raise thousands of young abalone and prepare them for release into nature. In late 2019, scientific divers from the Aquarium of the Pacific along with divers from other major institutions released the white abalones from holding boxes placed in undisclosed underwater locations.
SPECIES IN DETAIL | Print full entry
White Abalone
Haliotis sorenseni
CONSERVATION STATUS: Endangered
CLIMATE CHANGE: Vulnerable
Southern California Gallery
Historically, white abalone were found in the Pacific Ocean from Point Conception, California, USA to Punta Abreojos, Baja California, Mexico. Today there are low numbers of white abalone along the mainland coast of southern California and on offshore islands and banks. The status of the species in Mexico remains largely unknown.
Found on rocky substrates alongside sand channels usually found at depths of 15-55 meters (50-180 feet).
Young abalone hide in rock crevices, under rocks and even under sea urchin spines. Adults are often found on rocks, closer to the sandy zone.
Sand channels are believed to help the white abalone capture algae that are often found floating between the channels.
Marine snail with a thin, oval shell containing a row of three to five holes used to breathe, excrete waste, and reproduce. The inside of the shell is a pearly white. The epipodium (the raised ring below the shell, above the foot) is green and beige with dark brown tentacles.
The bottom of the foot is an orange muscle used to move, attach to rocks, and sense the surrounding environment. Abalone blood has no clotting ability, making it easily susceptible to mortality when nicked by divers trying to remove the animal from a rock.
Up to 25.4 cm (10 inches) and between 0.5-0.9 kg (1-2 pounds).
White abalone grow 10 to 29 millimeters (0.4 to 1.1 inches) per year.
In the wild white abalone eat different types of drift algae and macroalgae, such as kelp. They use the front part of their foot to capture drift algae and bring it to their mouth. White abalone feed most actively at night.
At the Aquarium of the Pacific, white abalone may be fed kelp and other macroalgae.
White abalones reach sexual maturity between 4 to 6 years of age, when they are about 10 centimeters (4 inches) in size.They are broadcast spawners, releasing eggs and sperm into the water by the millions when environmental conditions are optimal. Broadcast spawning relies on other abalone being within several feet to help ensure the eggs have an opportunity to be fertilized. Embryos develop into free swimming planktonic larvae, eventually settle down to the substrate as juvenile, and grow into adults.
White abalone raised in hatcheries were found to reproduce at younger ages and smaller sizes.
White abalone feed most actively at night, preferring low light conditions. White abalone are slow moving, which makes them highly susceptible to aggressive predators such as humans.
Due to overfishing within the human accessible zones, white abalone are now found living at deeper depths. Historically, they could be found as shallow as 5 meters (16 feet), but now can mostly be found at 30-60 meters (98-196 feet).
30-40 years
The National Oceanic and Atmospheric Administration (NOAA) in collaboration with the Aquarium of the Pacific, the UC Davis Bodega Marine Laboratory, the Bay Foundation, Paua Marine Research Group (PMRG), the California Department of Fish and Wildlife, and various other partners have been working together to help save the white abalone from extinction - this is the first time in history that this federally protected species is being released into the wild.
White abalone are kelp forest architects! They graze on kelp helping to promote kelp and animal diversity by clearing patches of rocky surfaces to make room for a variety of kelp species, fish, and other animals.
White abalone are forgotten treasures! There are so few white abalone in nature that the species is nearing extinction. The Aquarium of the Pacific has been working with NOAA for over 11 years on a White Abalone Recovery Program to raise thousands of young abalone and prepare them for release into nature. In late 2019, scientific divers from the Aquarium of the Pacific along with divers from other major institutions released the white abalones from holding boxes placed in undisclosed underwater locations.