Virginia Oyster Reef Heritage Foundation supports research at the VCU Rice Center
The Virginia Oyster Reef Heritage Foundation has provided a gift to the VCU Rice Center in support of research by Bonnie Brown, Ph.D., professor of biology, on a flatworm that can cause high mortality of young oysters. Oyster aquaculturists along Atlantic-coast states consider Stylochus ellipticus, a predatory flatworm, to be a scourge of oyster cultivation because an invasion of this flatworm can cause 30-100 percent mortality of oysters up to 1 centimeter in length. Results of a recently published VCU study indicate that poor wild oyster set may be linked to the presence of S. ellipticus.
The funding from the foundation will allow Dr. Brown and colleague Dr. Aaron Aunins (VCU Department of Biology) to initiate an investigation of the distribution of S. ellipticus in the James River. Because the early life stages of S. ellipticus are difficult to detect, the project will begin with development of molecular markers that can be used to reveal the presence of the flatworms in biofilms on substrate that oyster spat colonize. Through collaboration with Roger Mann, Ph.D., and Melissa Southworth, Ph.D., at the Virginia Institute of Marine Science, the study will then examine biofilms produced on shellstrings deployed for annual spatfall monitoring, providing data to determine if the occurrence of S. ellipticus is correlated with water temperature and salinity. In a separate collaboration with Jonathan Allen, Ph.D., of The College of William & Mary, studies are underway to develop enhanced preservation methods and investigate salinity tolerance to determine strategies for minimizing the effects of Stylochus on recently set oyster spat. Overall, the study will provide insight regarding the importance of S. ellipticus as a potential driver of poor natural oyster recruitment in the James River and other Chesapeake Bay tributaries, and should be particularly useful for enhancing the success of spat-on-shell programs.
Top right: The oyster team — Aaron Aunins, Bonnie Brown, Cliff Schroeder (President, Virginia Oyster Reef Heritage Foundation), Jonathan Allen and Dennis Treacy (member of the boards of the VCU Rice Center and the Virginia Oyster Reef Heritage Foundation) — meets at the VCU Rice Center. Middle left: Bonnie Brown, Cliff Schroeder and Dennis Treacy talk about the parasite that attacks oysters. Bottom right: Bonnie Brown, Cliff Schroeder and Len Smock (Director, VCU Rice Center).