Causes of oyster seed (or spat) dieoffs

A Novel Proteomic-based Approach to Identify and Mitigate Factors Responsible for Shellfish Mortality Events

Use of shotgun proteomics to probe the causes of mysterious mass die-offs of oyster seed at hatcheries in Washington and Hawaii and assess implications for culture diet, water chemistry and microbes.

Principal Investigator

Steven Roberts,  UW School of Aquatic and Fishery Sciences

Co-Principal Investigators

Benoit Eudeline, Taylor Resources

Brent Vadopalas, UW School of Aquatic and Fishery Sciences

Project

Shellfish aquaculture, especially oyster farming, is the economic mainstay of many Washington communities. But since the late 1990s shellfish hatcheries have suffered mysterious mass die-offs of oyster seed, typically about one month after fertilization. Unlike mortality at the earlier larval stage, these die-offs are not associated with water-chemistry problems such as high levels of dissolved carbon dioxide, nor with pathogens; treating for these does no good. The seed losses threaten supplies that growers large and small depend upon. This project will test a key hypothesis: that differences in the abundance of various proteins and peptides presage die-offs. It will sample seed from oyster cohorts, some subject to die-offs and some not, at hatcheries in Quilcene, Washington, and Kona, Hawaii. It will then use shotgun proteomics to identify the protein biomarkers associated with die-offs and select peptides for targeted assays. This will provide a powerful tool for uncovering the causes of future die-offs.