Larval Exchange in Olympia Oyster Recovery

Recovery of the Native Olympia Oyster, Ostrea lurida, in Northern Puget Sound: Measuring the Larval Import to and Export from a Restored Subpopulation

Researchers use seawater chemistry to trace larval exchanges between Olympia oyster populations.

Read our feature story covering this project:

A Small Oyster Poised for a Big Comeback

Principal Investigator

Bonnie Becker, University of Washington, Tacoma, School of Interdisciplinary Arts and Sciences

Co-Principal Investigators

Brian Allen, Puget Sound Restoration Fund

Henry Carson, Washington Department of Fish and Wildlife

Betsy Peabody, Puget Sound Restoration Fund

Andrés J. Quesada, Northwest Indian College, Salish Sea Research Center

Brent Vadopalas, University of Washington, School of Aquatic and Fishery Sciences


Washington Sea Grant-funded researchers partnered with tribes, shellfish managers and a local restoration group to determine how far Olympia oyster larvae disperse. From 2015 to 2016, the researchers collected planktonic larvae and recent settlers, and sampled over 14,000 adults throughout Puget Sound to collect brooded larvae from more than 100 oysters using a novel sampling method that is non-lethal to the parent animal. The researchers then examined the larvae using elemental fingerprinting, a technique that measures the elemental makeup of the animal’s shell, which reflects the environment in which that shell was formed, which was used to map settlers back to the brooding region.



Washington’s only native oyster, the Olympia, was overharvested starting in the 1850s, resulting in its depletion. Despite protections instituted by state agencies, the species has yet to recover. Olympia restoration is now a regional priority whose success relies on reestablishing self-sustaining populations that can replenish surrounding beds. Information about how far Olympia larvae disperse in Puget Sound could aid these restoration efforts.


This study was the first use of elemental fingerprinting of an invertebrate in Puget Sound. Three regions in Puget Sound were found to have unique elemental fingerprints for brooded larvae. However, researchers were largely unable to map settlers back to brooding region based on data collected in this study. Despite that challenge, the ecological data gathered supports the conclusion that Olympias don’t travel far from their source, which is consistent with other findings and suggests that seeding Olympias near site of origin would provide greater restoration success. In addition, the study was successful in developing a non-lethal sampling technique which has been used in other studies. The project also provided workforce development opportunities for nine students.

Annual Reports

2017 Progress Report

2016 Progress Report

2015 Progress Report