Using Real-Time Polymerase Chain Reaction to Determine Spatial Distribution of Multiple Species of Shellfish

Abstract

The success of both wild and cultured shellfish populations is dependent upon recruitment of planktonic larvae. Due to issues of cost, time, expertise and inaccuracy associated with bivalve identification using microscopy, real-time polymerase chain reaction is being employed to identify and quantify larvae using DNA technology. We are quantifying species-specific abundance and distribution of four commercially important species using novel approaches. Environmental samples were collected via two rounds of in-situ pumping at four locations in intertidal waters in Washington State. Pumping was performed at two depths: near the water surface and above the sea floor and at two times: before sunrise and sunset, in order to determine the spatial and temporal distribution of bivalve larvae. Genetic assays for Pacific geoduck clam (Panopea generosa) Olympia oyster (Ostrea lurida), Pacific oyster (Crassostrea gigas) and Manila clam (Venerupis philippinarum) have been designed. The collected field samples are currently undergoing qPCR quantification using these assays. Results will be analyzed to determine cross-species patterns or species-specific behavior in larval distribution throughout Washington State. This information will provide a comprehensive snapshot of the larvae of multiple shellfish species in Washington. Additionally, this information may further be utilized by hatcheries by providing the best times and locations for hatcheries to plant cultured seeds and substrate and by researchers studying the effects of localized ocean acidification