PROJECTS

Oyster Growth and Longevity

TOGA Growth and Longevity Study

Introduction
TOGA is studying the growth rate and longevity of two strains of oysters, Delaware Bay (DeBy) and Louisiana (LoLa). There are both diploid (fertile) and triploid (sterile) animals of each strain, so each volunteer has four cages to monitor and measure. The project's objective is to record the longevity and growth patterns of selectively bred oysters available to aquaculture in different salinity regions within Tidewater VA. We know from studies at VIMS, personal observation, and elsewhere that selectively bred oysters are more disease resistant than in the past, but more data from various oyster growing areas on the strains are desired by oyster gardeners and others. In the past, we have seen anecdotal evidence of improved growth and longevity, but a careful study has not been conducted in the various growing areas. Although TOGA volunteers are not typically marine scientists, we have a record of collecting important information about oysters in conjunction with VIMS. The last part of the study involves data analysis by a graduate student to be arranged for through VIMS. The long term plan is to grow the oysters at least three years and assess mortality and growth of the three strains in the different salinity ranges.

Currently over 40 volunteers are each raising approximately 400 oysters, 100 each of two strains, DeBy (Delaware Bay) and LoLa (Louisiana). There are diploid (fertile) and triploid (sterile) animals from each strain so each volunteer has 4 kinds of animals, identified by colored cable ties. The oysters will be cared for in typical fashion by experienced volunteer oyster gardeners. The volunteers will also count the surviving oysters quarterly and measure the lengths of random samples. The volunteer sites are shown on the map and represent a wide range of salinities. The growth results are summarized below and on following pages.