Assessing seasonal variations in the physiological health of the Eastern Oyster, Crassostrea virginica



Cumulative mortality is a major issue within oyster culture. Under optimal conditions, a mortality of 5% per year is often observed, however these numbers can vary considerably between lease sites (Doiron, 2008). Producers compensate for these losses by increasing the number of oysters cultivated on their leases. However, increasing the number of oysters on each lease can greatly impact the environmental footprint of the site. Valuable resources within the ecosystem are lost (e.g. phytoplankton, nutrients, etc.) and on-site biodeposition is increased, without any return to the industry or consumers in terms of more oysters. This environmental impact becomes even greater in areas of reduced water exchange and areas of maximised carrying capacity. In New Brunswick, oyster mortalities appear to be closely related to environmental factors (e.g. temperature, salinity, etc.) and husbandry or rearing practices. The physiological health of the animal can determine how well it adapts and recovers from exposure to potential stressors. This study will assess variations in the health and condition of oysters (Crassostrea virginica) in New Brunswick in response to environmental changes to identify critical periods of physiological stress. This information will allow the development of management plans and best practices to help oyster producers avoid supplementary stressors, thus reducing mortalities and optimizing resource utilization. This could lead to more environmentally responsible operating practices for the oyster culture industry.

Program Name

Aquaculture Collaborative Research and Development Program (ACRDP)


2012 - 2015


Atlantic: Gulf of Maine, Scotian Shelf

Principal Investigator(s)

Daniel Bourque