Stocking fish is a common method of enhancing the perceived recreational value of a fishery. In New York, the State Department of Environmental Conservation stocks approximately 2.3 million catchable-size trout every year. These hatchery-raised fish augment wild populations and contribute to the fantastic fishing opportunities available throughout the the state.
My work focuses on creating and improving models that predict the dynamics of stream trout populations during the fishing season. These models take into account angler behavior, as well as natural causes of mortality, such as predation, that drive changes in the number of catchable fish present at a given time. The goal is to fine tune the time and density of stocking to create ample fishing opportunities throughout the season while minimizing expenditures and the impact to native fish communities.
This study involves multiple years of data from angler interviews and electrofishing population surveys. By uniquely marking fish from each stocking increment, we’re able to track mortality and movement from month-to-month as well as year-to-year. This data, in combination with observed angler catch rates and effort, can be used to estimate basic population parameters such as survivorship.