HA3 Effects of Multiple Stressors on Marine Resources
254 Portland Ballroom
8:00 AM - 12:00 PM, Thursday
() Exploring the Use of Marine Gastropods as Environmental Sentinels in the Bay of Fundy, Canada.
Edgell, T1, Brasfield, S1, 1 University of New Brunswick, Saint John, New Brunswick, Canada
ABSTRACT- Environmental Effects Monitoring (EEM) is a science-based tool designed to detect and measure potential changes in aquatic ecosystems resulting from industrial discharge. As such, EEM helps to determine the sustainability of human activities by monitoring the relative health of receiving environments. EEM compares demographic (e.g., size structure) and physiological (e.g., body and gonad mass) endpoints of sentinel fish species in receiving environments to those at reference sites. This methodology requires (i) selection of appropriate reference sites for comparison to potentially affected sites, and (ii) selection of sentinel species within those sites characteristic of phenotypically plastic endpoints (i.e., quantitative traits that are inducible by environmental conditions). It is recognized that most fish species in marine receiving environments are highly mobile, therefore their demographic and physiological endpoints are poor indicators of local environmental conditions. As a result, the EEM approach has been underutilized in marine areas. We have begun investigating the potential use of marine gastropods as sentinels in the context of EEM objectives. Periwinkles (Littorina obtusata) are particularly good sentinel candidates due to their broad distribution, limited mobility, and high abundance in intertidal areas. A major challenge to categorizing sentinel species stems from a lack of regional life-history information. In this study we monitored reproductive activity of adult periwinkles (e.g., hormone and egg production) in the Bay of Fundy. A field based apparatus was deployed to quantify seasonal reproductive output. Our objective was to monitor seasonal reproductive endpoints in an effort to (i) make recommendations regarding the value of gastropods as sentinel species in marine receiving environments and (ii) propose the most appropriate sampling time and design.
Key words: seasonality, fecundity, intertidal, environmental effects monitoring