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California’s only native oyster species, the Olympia oyster (Ostrea lurida), is getting a second chance along the state’s coast – and aquaculture is playing an important role.

Once abundant throughout California’s coastal waters, Olympia oysters declined dramatically due to historic overharvesting, sedimentation, habitat changes and other pressures. Today, researchers estimate that populations remain at roughly 1% of their historic abundance. Beyond the loss of the oysters themselves, declining oyster beds also eliminated important habitat for fish and other marine organisms while reducing the oysters’ natural water-filtering and shoreline-stabilizing benefits.

A decades-long effort led by researchers at UC Davis’ Bodega Marine Laboratory has demonstrated how hatchery technology, field research and aquaculture can work together to rebuild native oyster populations.

Researchers developed techniques to successfully culture Olympia oysters in hatcheries – a significant challenge because, unlike many oyster species, Olympia oysters brood their developing larvae before releasing them into the water. Hatchery production has since provided researchers with the ability to produce large numbers of juvenile oysters for research and restoration.

That work reached an important milestone in June 2026, when approximately 125,000 hatchery-produced Olympia oysters were placed at Sacramento Landing in Point Reyes. The project, conducted by UC Davis and The Nature Conservancy, represents the first “wild site” outplanting described in the UC Davis report and is the culmination of years of laboratory and field research.

Aquaculture as a Restoration Tool

Perhaps the most significant aspect of the project for California’s aquaculture industry is the emerging concept of “restoration aquaculture.”

The objective is not simply to produce oysters for restoration sites. Farmed and restored Olympia oysters can mature and reproduce, contributing larvae to surrounding waters. As populations increase, that natural reproduction could help establish self-sustaining wild populations over time. In this model, commercial aquaculture and ecosystem restoration can reinforce one another rather than operating as separate activities.

The research may also create opportunities for California growers to diversify into native Olympia oysters. UC Davis notes that Olympia oysters are not susceptible to some diseases affecting commercial Pacific and Kumamoto oysters, including OSHV-1. Locally produced native oyster seed could also reduce reliance on seed transported from outside California and potentially reduce biosecurity risks associated with moving organisms across regions.

Researchers are now exploring remote-setting techniques, which could allow juvenile oysters to be produced closer to restoration sites rather than transporting oysters and substrate long distances from a central hatchery. This approach could potentially expand production capacity while reducing transportation requirements and creating additional opportunities for hands-on aquaculture and restoration training.

The Olympia oyster project is an excellent example of how California aquaculture can contribute to both food production and coastal ecosystem resilience.

As the industry continues to evolve, partnerships among growers, hatcheries, universities, conservation organizations and government agencies could create new opportunities to produce native species, restore habitat, strengthen coastal ecosystems and develop new markets.

The lesson is broader than oysters: aquaculture can be part of the solution to restoring California’s marine resources while supporting a productive and sustainable coastal economy.

Read the full UC Davis story: Restoring California’s Native Oyster