The number of native oysters off the California Coast has been diminishing to the point that only a sparse population is left. But, a group of students on the South Coast are gathering information to help future oyster recovery efforts.
Graduate students from UC Santa Barbara’s Bren School of Environmental Science and Management are trekking across the Carpinteria Salt Marsh Reserve on land and in water in search of native California oysters called Olympia oysters.
But they’re not easy to find.
"There’s some remnants of oysters that once lived on the rock but are no longer,” said Desmond Ho, a Master’s student at UCSB’s Bren School, finally locates one.
He’s one of five graduate students working on this Southern California Native Oyster Restoration Project that’s funded by the Honda Marine Science Foundation.
“Since their [ native oysters ] numbers have been so low for the last 50, 60, 70 years, a lot of people are not aware of their existence,” Ho said.
Along the coastline, you’ll find plenty of Pacific oysters, which come from Japan. But grad student Emily Read says not very many Olympia oysters.
“The native oyster is a really clear example of how humans have polluted the environment, over-harvested oysters. And that has resulted in their severe declines of their populations all along the California Coast,” she said.
The value in restoring the native oysters is tremendous, says Hunter Lenihan, a UCSB professor of marine ecology and conservation and the faculty advisor for this project.
“They build reefs, so they’re what we call ecological engineers. And many other organisms use those reefs as habitats. So they have a positive impact on biodiversity. They also filter water so can have a positive influence on water quality. And then they provide a source of food for animals that eat them. Some crabs, fish and birds,” he said.
However, this project will not actually restore the numbers, but instead provide tools and incentives to motivate future restoration efforts. In doing so, the students have been keeping track of the Olympia oysters they have discovered and using that data as well data from other researchers to create a map that shows exactly where these native oysters are being found.
“When there are oysters present that shows that there is potential for restoration project, meaning that the conditions there are favorable to them because they are found there,” said grad student Erin Winslow, who’s also the project manager.
Since restoration is expensive, their project also entails laying out economic incentives, like this one.
“Using oysters as a means of shoreline stabilization may be a cost-effective method to mitigate erosion. So, I’m sure you and everybody has seen the big bulldozers along our coastlines that are shoveling sand in and out of beaches. We think that oysters may serve as an alternative way to stabilize our shorelines," said Winslow.
She says their research shows just how important it is to restore Olympia oysters.
“Not only because we have a moral obligation to do so, but they do offer a lot of ecosystem services for us as people as well as the environment around us,” Winslow said.
As these students search for native oysters that are hard to come by, they’ll locate just a few. However, the hope is that there will be plenty more to find in the future.