Grantee Research Project Results

Behavioral and Physiological Responses of Blue Crabs to Episodic Hypoxia: A Mechanistic Approach for Linking Water Quality, Physiology, Behavior, and Population-Level Consequences

EPA Grant Number: F5E11143
Title: Behavioral and Physiological Responses of Blue Crabs to Episodic Hypoxia: A Mechanistic Approach for Linking Water Quality, Physiology, Behavior, and Population-Level Consequences
Investigators: Bell, Geoffrey W.
Institution: North Carolina State University
EPA Project Officer: Lee, Sonja
Project Period: September 1, 2005 through September 1, 2008
Project Amount: $97,317
RFA: STAR Graduate Fellowships (2005) RFA Text |  Recipients Lists
Research Category: Academic Fellowships

Objective:

My research assesses the ecological impacts of poor water quality (i.e. hypoxia) on an ecologically and economically important crustacean, the blue crab. My study provides a mechanistic understanding of how hypoxia alters mortality rates and spatial distribution patterns of blue crabs by first understanding the behavioral and physiological responses of individuals to hypoxia and then scaling up these patterns to the population-level.

The overall objective of my research is to quantify the behavioral and physiological responses of individual blue crabs to hypoxia in order to develop and field-test an individually-based, spatially explicit model that predicts mortality rates and changes in spatial distribution patterns of blue crab populations during dynamic hypoxic events.

Approach:

My multidisciplinary approach uses a series of laboratory, modeling, and field experiments to understand the physiological and behavioral mechanisms of blue crabs that control population-level processes (e.g. mortality and spatial distribution patterns) during hypoxic events. Laboratory experiments will quantify survivorship as well as movement and physiological responses to hypoxia hydrodynamics. Lab results will help parameterize an individual-based, spatially-explicit model that predicts mortality rates and spatial distribution patterns of blue crab populations during hypoxic events. Model predictions will be field-tested by tracking movements of free-range crabs with state-of-the-art biotelemetry technology during hypoxic events. This study should provide key insights into the linkages between water quality, physiology, and behavior that can predict the ecological impacts of hypoxic disturbance events.

Expected Results:

The intellectual merit of my study is that it can identify key relationships between hydrography, physiology, and behavior, which provide a mechanistic understanding of how hypoxia alters estuarine population dynamics. Mechanistic models are particularly useful for studying dynamic processes, such as hypoxia, because they account for variability in environmental conditions and differences among individuals. Therefore, my model can be a powerful tool for managers that want to predict the ecological impacts of disturbance events over large time scales, during which environmental conditions change, and in systems for which data are not readily available . This study will connect water quality to the population dynamics of an ecologically and economically important estuarine animal, which is critical for directing water quality and fisheries management initiatives.

Supplemental Keywords:

water quality, hypoxia, physiology, behavior, blue crab, biotelemetry,, Scientific Discipline, Ecosystem Protection/Environmental Exposure & Risk, Habitat, Environmental Monitoring, Ecology and Ecosystems, Ecological Risk Assessment, habitat dynamics, Blue Crab Callinectes Sapidus, environmental sources of mortality, community composition, habitat disturbance, hypoxia, conservation biology, environmental stress, water quality, biotelemtry technology, mortality

Progress and Final Reports:

2006

2007

Final