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Gretchen A. Hansen

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Understanding Historical and Predicting Future Lake Temperatures in North and South Dakota
Lakes, reservoirs, and ponds are central and integral features of the North Central U.S. These water bodies provide aesthetic, cultural, and ecosystem services to surrounding wildlife and human communities. External impacts – such as climate change – can have significant impacts to these important parts of the region’s landscape. Understanding the responses of lakes to these drivers is critical for species conservation and management decisions. Water temperature data are foundational to providing this understanding and are currently the most widely measured of all aquatic parameters with over 400 unique groups monitoring water temperature in U.S. lakes and rivers. However, lake temperature data are lacking at...
Largemouth Bass (LMB) Micropterus salmoides is one of the most popular sport fish in the United States and is intensively managed across much of its range. Beginning in 1989, Wisconsin implemented more restrictive harvest regulations for LMB, including greater minimum length limits, reduced bag limits, and a catch-and-release-only season during the spawning period across much of northern Wisconsin. We tested for trends in LMB relative abundance, growth, and angler catch and harvest in relation to LMB management policies from 1990 to 2011. We also tested for potential sport fish community responses to changes in LMB abundances using Walleye (WAE) Sander vitreus as an example. Angler catch rates and electrofishing...
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