Science Serving Maryland's Coasts

Jennifer (Hurt) Bergman, University of Wisconsin

Class Year: 
2004

Project Title: 

Applying Bioenergetics to Determine Predatory Demand of Weakfish in the Chesapeake Bay

Abstract: 

We completed an updated bioenergetics project to quantify the predatory demand of weakfish in the Chesapeake Bay during multiple years to determine if prey supply was limiting. Consumption was estimated for a representative individual in several age classes and juvenile cohorts based upon an observed growth, dietary proportions, water temperature, and known physiological parameters. Population consumption was compared to prey supply production estimates. Bay anchovy was the dominant prey item found in weakfish diets. Weakfish population-level consumption of bay anchovy ranged from 1.15% to 15.66% of the bay anchovy production and did not significantly change in the period 1995-2002. Negative growth rates were observed for age-2 and older weakfish during summer months. We conclude that prey could be limiting for the weakfish population during the summer months due to a function of temperature because energy demands were not met for growth.