AUTHORS: Brenden Elwer, Department of Natural Resource Management, South Dakota State University; Alison Coulter, Department of Natural Resource Management, South Dakota State University; Zachary Feiner, Office of Applied Science, Wisconsin Department of Natural Resources, Science Operations Center and Center for Limnology, University of Wisconsin-Madison; David Coulter, Department of Natural Resource Management, South Dakota State University
ABSTRACT: Preventative monitoring is an important tool for managing invasive species. Monitoring programs can detect invasions soon after introductions, allowing for rapid response actions that lead to successful containment or eradication. Individuals likely congregate in areas of highest habitat quality, so understanding how habitat quality changes through space and time can be useful for invasive species management by ensuring sampling and response efforts target locations where new invaders are likely to be present. For this work we assessed spatial and temporal trends in habitat quality for Silver Carp, Hypophthalmichthys molitrix, in currently uninvaded lakes, rivers, and wetlands in eastern North and South Dakota. We did so by calculating water temperature, water velocity, phytoplankton density, and zooplankton density from observed monthly sampling across 30 m x 30 m grid cells in each water body. Observations were then used in bioenergetics models that calculated growth rate potential, an index of habitat quality, that we compared through space and time. Developing our understanding of how high-quality habitat patches for Silver Carp shift over time enables more effective monitoring and preventative action planning for resource managers.
