Scientist Refines Models Relating River Flows to Fish Habitat and Population Dynamics
A Northern Research Station fish biologist studying salmon and trout found that models relating river flows to fish habitat and population dynamics need to acknowledge the complex life histories of riverine and diadromous fish and also need to integrate stage-specific effects on population dynamics.
Rivers flowing into the North Atlantic Ocean, Eastern North America, and Northwestern Europe have a long history of being modified for human use. Faced with increasing demands for water and hydropower energy and with fisheries and other ecosystem services at risk, land managers desperately need sound science for informed decision making.
Forest Service scientists reviewed the state of science relating river flow regimes to fish populations and outlined a framework for moving forward. Scientists made the case that to generate robust predictions, models need to acknowledge the complex life histories of riverine fishes and also need to integrate stage-specific effects on population dynamics, including compensatory responses.
Forest Service scientists also demonstrated that many existing models rely on tenuous relationships between fish and predicted suitable habitat under altered flows. Using long-term data on river flow and fish growth and survival, the scientists showed that these approaches could easily generate erroneous conclusions. They suggested that an adaptive management approach, in combination with a network of long-term study sites, could substantially increase our understanding and significantly advance the field.
Forest Service Partners