Scientists celebrating breakthrough in race to save endangered white abalone at UC Davis Bodega Marine Lab
Scientists are celebrating a population boom among endangered white abalone being raised at the UC Davis Bodega Marine Lab as they approach the day they can begin introducing captive-bred sea snails into their natural ocean habitat — perhaps later this year or next.
The good news comes mainly as a result of the reproductive success of a single champion egg producer who, with her supporting cast, recently contributed about 12 million new larval specimens to the program, lab scientists said.
The fecundity of the abalone tagged Green 312 is all the more significant because she is among nine mollusks carefully hunted and collected from the wild over the past two years under a special federal permit allowing for added genetic diversity in the captive breeding program.
“It’s monumental for this program and for the future of this species,” Program Director Kristin Aquilino said.
Large-scale reproduction is critical both because of the high mortality rate among larvae, as they transition through life stages, and because so many mature abalones are needed to restock the species — the first marine invertebrate listed as endangered under the federal Endangered Species Act in 2001.
But though researchers have resorted to mood music, timed lights and even a “romantic love potion” that’s hydrogen-peroxide based, they have found it a struggle to unlock the key to the white abalone’s ardor.
Scientists managed to accumulate about 100,000 juvenile abalones between 2001 and 2003, when the captive breeding program first got started in Southern California with 18 wild adults plucked from the ocean near the Channel Islands.
But the majority were lost to a bacterial disease that was able to thrive in the region’s warm water before they could go far with it.
The clean, cold waters of Bodega Bay and local expertise on invertebrate health identified the UC Davis marine lab as a natural alternative site for the relocated program. It was finally underway in 2011, housed primarily in an artificially lit room filled with tanks and trays that are home to different age classes of juvenile white abalone and the mature mollusks from which they sprang.
But between 2003 and 2012 there was no successful reproduction, slowing the prospect of the species’ recovery even as scientists developed the plan under which they planned to pursue it.
Between 2012 and 2017, using the original brood stock now divided between partnering institutions, seasonal spawning sessions began producing enough young to establish an inventory of young abalone. But none of the females were producing the number of eggs even close to what they should be, Aquilino said.
Green 312 had already shown herself to be a prolific spawner when she produced eggs on the boat at the time she was collected in 2017 and again four weeks later in the lab, Aquilino said.
Last week she produced more than 20 million eggs — so many that, combined with surviving embryos from other spawning abalone, Aquilino and her team had to farm out 10.5 million larvae to be raised by nine partnering institutions and nonprofits in the White Abalone Recovery Consortium. They still had enough to keep 1.5 million in the Bodega Bay lab.
“Her contribution to the future of her species is really critical, and her spawning really does represent the future of her species,” Aquilino said of white abalone G 312.