Science Weekly: Saving White Abalone


White abalone are apparently the most delicious abalone, fetch the highest price at market – and have been off the market since 1997, due to overharvesting and dangerously low wild populations.

Dr. Kristin Aquilino, project scientist at Bogeda Marine Laboratory, has been with UC Davis Marine Lab for 11 years. She explained the challenges wild white abalone face and what the scientists at Bodega Bay are doing to save and repopulate them to a group of environmental journalists visiting the lab in coastal California on Thursday.

“These animals are really important to the ecologies of our oceans,” Aquilino said enthusiastically, and “tell people how adorable they are – which I will convince you of by the end of this tour.”

From small, shy little shells, to fist-sized, orange and yellow adults, white abalone are some of the more important – but unfortunately, palatable – creatures on the west coast.

White abalone were “fished to virtual extinction in the 1970s, there’s probably only a few thousand left in the wild,” Aquilino explained. And as they are broadcast spawners, sending their eggs and sperm out into the water separately, these animals need to be close together to reproduce effectively.

“The ones that are left are so sparse, that they’re effectively sterile. So the population might effectively already be extinct.”

They became the first marine invertebrate species to be listed as federally endangered in 2001.

“We thought when we listed them, they’d be a pretty easy species to save,” Aquilino said. “There’s abalone farms all over the world – so white abalone, let’s just take those, let’s use the methods that everybody else is using and make a bunch of them, and we’ll figure out how to put them back out in the wild.”

But after wild animals were collected that year for the breeding program and over 100,000 juveniles were created, most died from disease.

Withering foot syndrome is a bacteria affecting abalone all over the world. It’s temperature dependent, and when water gets too warm, the bacteria proliferate, the animal can’t digest its food, its foot shrinks, and it falls off the rock and dies.

So in 2011, the project moved up to Bodega Marine Laboratory because of its research expertise and the state’s shellfish health expert, who has been instrumental in learning to track and treat this disease. So now, they have healthy animals again.

In the first successful breeding year at Bodega, they only made 12 adult white abalone. But in the next year, 120 – then thousands.

This past spring of 2016, 13,000 juvenile abalone survived, and today 15,000 white abalone live in the lab.

Compare this with the mere few thousand left in the wild. Aquilino calls it, “really, really promising.”

White abalone are the deepest of all California abalone species, living all the way from 40 to 230 feet below the surface.

And the good news is that white abalone habitat is relatively intact. So they should do well when released in the ocean.

The lab is probably still a year or two out from doing that, between receiving the proper permits and finding the best habitats to place these creatures back in the wild.

“Aren’t they cute?” Aquilino exclaimed at the end of the tour, holding up a decently large 3.5-year-old specimen by the shell. Its bright colors glistened in the light and it stretched its delicate underbelly, almost waving at me, as it explored its surroundings.

“Yeah,” I laughed, grinning: “strangely and convincingly cute.”