Midwest Fish & Wildlife Conference 2018

AUTHORS. Andrew K. Carlson, Michigan State University; William W. Taylor, Michigan State University; Zeenatul Basher, US Geological Survey; T. Douglas Beard, Jr., US Geological Survey; Dana M. Infante, Michigan State University

ABSTRACT. Projected increases in coldwater stream temperatures resulting from predicted air temperature warming over the next 50 years are cause for concern among fisheries professionals that manage brook trout (Salvelinus fontinalis), brown trout (Salmo trutta), and rainbow trout (Oncorhynchus mykiss). There is a need for management approaches that promote thermally resilient stream ecosystems that can sustain their cold temperature regimes and trout populations in a changing climate. We developed temperature models that account for the effects of groundwater and precipitation on stream thermal regimes and used these models to project the effects of climate change on trout growth and survival in Michigan. We then collaborated with Michigan fisheries professionals to synthesize modeling results into a decision-support framework to facilitate resilience-based management in 52 trout streams throughout the state. Groundwater- and precipitation-corrected models were more effective than standard air-stream temperature models in explaining differences in stream thermal regimes, indicating that simple alterations to traditional models can improve accuracy and management utility. When integrated into a decision-support framework, groundwater- and precipitation-corrected models enables fisheries professionals to make ecologically, socioeconomically robust management decisions that promote thermally resilient streams and trout populations. Managers can use decision-support tools to anticipate future thermal, hydrological, biological, and socioeconomic conditions in trout streams and thereby make informed decisions for resilience-based management. With implications and applications beyond Michigan trout streams, our research demonstrates the utility of synthesizing diverse information sources to facilitate efficient, effective decision-making amid complex fisheries management environments in a changing climate.