The Effect of Temperature on Depuration of the Pathogenic Vibrio anguillarum in the Eastern Oyster (Crassostrea virginica)
Presentation Abstract
Shellfish serve as first line sentinels to measure challenges to ecosystem health, including marine toxins, viruses and pathogenic bacteria. Many vibrios occur naturally in coastal estuaries at generally low abundances, but pathogenic vibrio species can become human health issues when they proliferate during warm periods. Depuration of these pathogens from bivalves, either by flushing of the digestive organs or pseudofeces voidance from the mantle, varies as a function of bivalve pumping rates and bacterial growth rates. Although this process is reasonably well understood for warmer water conditions, such as the Gulf of Mexico, there is far less information about pathogenic bacteria depuration rates under higher latitude, cold water conditions. Projecting how climate change at higher latitudes may affect oyster and other bivalve aquaculture requires knowledge of how increasing temperature influences the depuration rates of these species. We show that depuration times of the eastern oyster Crassostrea virginica increase sharply as a function of temperature between 15-25°C, a difference attributable mainly to temperature effects on bacterial growth rates. In natural systems, the increase in stratification from climate-driven temperature increases also affect the character and abundance of phytoplankton and detritus; factors that could lead to increased gut residence times and thus even longer depuration times. Our data provide a starting point for modeling these and other climate change effects on oyster depuration efficiencies, and suggest that longer windows of warm periods in future will require alternate strategies for management of aquaculture farms, particularly in the sheltered waters of the Salish Sea.
Session Title
Harmful algal blooms (HABs) and marine pathogens in a changing world
Conference Track
Climate Change and Ocean Acidification
Conference Name
Salish Sea Ecosystem Conference (2016 : Vancouver, B.C.)
Document Type
Event
Location
2016SSEC
Type of Presentation
Poster
Genre/Form
presentations (communicative events)
Contributing Repository
Digital content made available by University Archives, Heritage Resources, Western Libraries, Western Washington University.
Subjects – Topical (LCSH)
Vibrio cholerae--Salish Sea (B.C. and Wash.); American oyster--Climatic factors--Salish Sea (B.C. and Wash.); Aquaculture industry--Sanitation--Salish Sea (B.C. and Wash.)
Geographic Coverage
Salish Sea (B.C. and Wash.)
Rights
This resource is displayed for educational purposes only and may be subject to U.S. and international copyright laws. For more information about rights or obtaining copies of this resource, please contact University Archives, Heritage Resources, Western Libraries, Western Washington University, Bellingham, WA 98225-9103, USA (360-650-7534; heritage.resources@wwu.edu) and refer to the collection name and identifier. Any materials cited must be attributed to the Salish Sea Ecosystem Conference Records, University Archives, Heritage Resources, Western Libraries, Western Washington University.
Type
Text
Language
English
Format
application/pdf
The Effect of Temperature on Depuration of the Pathogenic Vibrio anguillarum in the Eastern Oyster (Crassostrea virginica)
2016SSEC
Shellfish serve as first line sentinels to measure challenges to ecosystem health, including marine toxins, viruses and pathogenic bacteria. Many vibrios occur naturally in coastal estuaries at generally low abundances, but pathogenic vibrio species can become human health issues when they proliferate during warm periods. Depuration of these pathogens from bivalves, either by flushing of the digestive organs or pseudofeces voidance from the mantle, varies as a function of bivalve pumping rates and bacterial growth rates. Although this process is reasonably well understood for warmer water conditions, such as the Gulf of Mexico, there is far less information about pathogenic bacteria depuration rates under higher latitude, cold water conditions. Projecting how climate change at higher latitudes may affect oyster and other bivalve aquaculture requires knowledge of how increasing temperature influences the depuration rates of these species. We show that depuration times of the eastern oyster Crassostrea virginica increase sharply as a function of temperature between 15-25°C, a difference attributable mainly to temperature effects on bacterial growth rates. In natural systems, the increase in stratification from climate-driven temperature increases also affect the character and abundance of phytoplankton and detritus; factors that could lead to increased gut residence times and thus even longer depuration times. Our data provide a starting point for modeling these and other climate change effects on oyster depuration efficiencies, and suggest that longer windows of warm periods in future will require alternate strategies for management of aquaculture farms, particularly in the sheltered waters of the Salish Sea.
