Collection of white abalone boosts recovery efforts
The white abalone stood alone on a rocky shelf, deep underwater off the West Coast near Los Angeles. The highly endangered shellfish had little chance of reproducing without any other of its species nearby.
Divers in late October collected the lone animal under a new permit from NOAA Fisheries to help inject new genes into a captive breeding program that is rearing white abalone for eventual release and recovery. It was the first white abalone collected from the wild in more than a decade.
Divers collect an endangered white abalone from a rocky shelf off the West Coast near Los Angeles.
“This adds significantly to the genetic diversity of the captive population, and ensures that this abalone’s genes will live on,” said David Witting of NOAA’s Restoration Center and one of the divers who collected the abalone from a rocky reef amid a dense understory of algae. “We were lucky to have found it. They are very cryptic and harder to find than it seems.”
Divers from the California Department of Fish and Wildlife also participated in the collection. The team took the abalone directly to the Aquarium of the Pacific in Long Beach, which is holding the rare animal until scientists move it to UC Davis’ Bodega Marine Laboratory, the center of the captive breeding program.
The program has proved increasingly successful at spawning captive white abalone. The challenge is that the young are all the offspring of very few original animals, so they are closely related siblings with very limited genetic diversity.
Genetic diversity is important to a species’ resilience in the wild, and ability to resist disease and other threats, said Susan Wang of NOAA Fisheries’ West Coast Region, who developed the permit allowing the collection of up to 30 wild abalone over five years. The permit allows the collection of only isolated animals unlikely to ever reproduce in the wild. To make sure animals are isolated, divers must survey the surrounding area to check for any potential mates.
Kristin Aquilino displays an endangered white abalone at Bodega Marine Laboratory. Aquilino leads the captive breeding program for the endangered shellfish.
“They’re effectively sterile because they’re too far away from any other abalone to spawn,” said Kristin Aquilino, who leads the captive breeding program at Bodega Marine Laboratory. “By bringing the animal in, we’re giving it the opportunity to contribute to the future of the species.”
At first scientists struggled to persuade white abalone to reproduce in captivity after collecting the first of the shellfish in the early 2000s. Borrowing techniques from commercial abalone farms that lent their advice and expertise, the program became increasingly successful. This year the program produced 13,000 young abalone, the most ever.
“There are now many more white abalone in captivity than we know of in the wild,” Aquilino said. “That’s scary for the population, but presents a great opportunity to save them.”
The next major step will be release of white abalone back into the wild. Scientists believe they still have more to learn about how to return white abalone to the ocean in ways that give the endangered animals the greatest chance of survival. The California Department of Fish and Wildlife and the Bay Foundation have begun pilot outplantings of animals using the similar but more common red and green abalone, Aquilino said.
The increasing number of captive white abalone also gives scientists greater opportunity to test different foods and other strategies to produce the healthiest and most resilient white abalone possible. Some white abalone have also been distributed to other facilities including NOAA Fisheries Southwest Fisheries Science Center, the Aquarium of the Pacific, Cabrillo Marine Aquarium and the Santa Barbara Museum of Natural History Sea Center to ensure against a disease outbreak or other risks to the captive population.
“This is a strong partnership among many agencies and organizations that are contributing important time and resources to recovering white abalone,” said Chris Yates, Assistant Regional Administrator for Protected Resources in NOAA Fisheries’ West Coast Region. “The strength of the collaboration sets this species up for success.”