Water Temperature Mapping from a Fish Population Modeling Perspective

Many rivers in the pacific Northwest have altered sediment, thermal, and hydrological regimes that can impact fish populations. Ecological models can be used to understand the influence of altered thermal regimes on fish populations. We present and discuss the spatial temperature requirements for two fish population modeling tools. We give a brief overview of the two models: 1. A fish assemblage network model; and 2. An individual based model of upstream migration by salmonids. Then, we discuss the challenges of parameterizing the model thermalscapes at varying temporal and spatial scales.

Impact/Purpose

Many rivers and streams in the Pacific Northwest are currently listed as impaired under the Clean Water Act as a result of high summer water temperatures. Adverse effects of warm waters include impacts to salmon and steelhead populations that may already be stressed by habitat alteration, disease, predation, and fishing pressures. Much effort is being expended to improve conditions for salmon and steelhead, with increasing emphasis on understanding impacts of climate change. This presentation will describe modeling approaches being applied by the EPA to link changes in water temperatures to fish population responses and describe challenges in creating the model input temperature maps.

Citation

Snyder, M., Joe Ebersole, AND M. Fuller. Water Temperature Mapping from a Fish Population Modeling Perspective. River Analytics Symposium, Corvallis, OR, October 29, 2019.