Drs. Cindy Heil and Nicole Poulton, along with Dr. Carter Newell of Pemaquid Oyster Company, received a SEANET mini grant from University of Maine to study the diet of oysters on the Damariscotta River in Midcoast Maine. The grant, which was awarded to projects that complement the work of the larger National Science Foundation SEANET (Sustainable Ecological Aquaculture Network) initiative run through the University of Maine, aims to examine how seasonal differences in groups of phytoplankton, the primary food source for oysters, impact oyster growth and productivity in the Damariscotta River.

The study, already underway, will conduct sampling at the Pemaquid Oyster Farm on the Damariscotta River four times throughout the 2016 growing season, with samples representing late spring, early and late summer and early fall. The oysters provided by Dr. Newell will be contained in a specialized flow-through chamber in which both water flowing in and out will be sampled using a FLOWCam. The FLOWCam will analyze the phytoplankton community composition. Oyster size and weight will be measured before and after each experiment, and the data will be used to analyze grazing preferences of oysters over the course of the growing season, and how it impacts oyster productivity in the Damariscotta River.

“Shifts in natural phytoplankton populations toward smaller-sized cells can reduce bivalve productivity” explains Dr. Heil. “This study will help us better determine the specific phytoplankton that oysters prefer to graze on throughout their growing season, providing valuable insights for the aquaculture industry.”

Drs. Heil, Poulton, and Research Technician Laura Lubelczyk completed the first sampling trip in mid-July with three more scheduled in 2016.

Photo: An oyster incubation apparatus used for sampling at Carter Newell's Damariscotta River site. (Credit: Laura Lubelczyk)