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South Milwaukee, WI, United States

Selzer M.D.,Office of the Great Lakes | Joldersma B.,Office of the Great Lakes | Beard J.,Public Sector Consultants Inc.
Journal of Great Lakes Research | Year: 2014

The Saginaw Bay watershed is unique and remains one of the most diverse watersheds in Michigan, containing the largest contiguous freshwater coastal wetland system in the United States. The watershed and Saginaw Bay support a wide variety of flora and fauna, agriculture and recreation opportunities. However, the rapid industrialization and population growth of the watershed in the 20th century strained the region's natural resources. Excessive nutrient loading, elevated bacteria levels, aquatic habitat loss, and chemical contamination all altered the watershed's ecosystem. These stressors contributed to declining fish and wildlife populations, loss of coastal wetlands, water quality concerns, beach closings, and the buildup of contaminants in the food web. Over the past four decades, extensive federal, state, and regional priority-based assessments and planning have positioned the Saginaw Bay watershed for significant restoration. There is a continued commitment by federal, state, and regional partners to advance restoration efforts. This paper reflects upon those activities and provides additional actions that would aid restoration work in the Saginaw Bay watershed and in the Saginaw Bay, a region of the Great Lakes that still must address significant environmental challenges to reach its full potential. © 2013.

Fayram A.H.,Office of the Great Lakes | Tober Griffin J.D.,Office of the Great Lakes | Wendel J.L.,Bureau of Fisheries Management
Aquatic Ecosystem Health and Management | Year: 2014

Walleye (Sander vitreus) populations in Wisconsin are near the center of their geographical range and support valuable fisheries. The role of seasonal temperature and precipitation in Walleye recruitment was examined using regression tree analysis. Climatological variables were estimated at the 8 km2 scale and Walleye recruitment was estimated based on 298 individual electrofishing surveys. Estimated changes in Walleye recruitment between 1950 and 2006 were examined based on changes in explanatory climatological variables. Spring precipitation and summer maximum temperature were significant predictors of age-0 Walleye density and mean estimated changes in these variables between 1950 and 2006 were used to estimate changes in Walleye recruitment. The model predicted a small overall increase in Walleye recruitment and provides insight into the direct role of climatological variables in Walleye recruitment. However, given the low explanatory power (R2 = 0.103), it is likely that historic climatological changes have had a limited effect on recruitment levels. © 2014 Copyright © 2014 AEHMS.

Fayram A.H.,Office of the Great Lakes | Weigel B.M.,United Road Services | Lyons J.,United Road Services | Simmons T.,Office of the Great Lakes
Aquatic Ecosystem Health and Management | Year: 2014

Smallmouth Bass (Micropterus dolomieu) is an important sportfish and has been suggested as a restoration target species in degraded aquatic environments such as "Areas of Concern" in the Great Lakes basin. Determining expected relative densities of fish and wildlife populations, such as Smallmouth Bass, in least-impacted situations is central to developing effective monitoring programs, assessing the level of relative impairment, determining appropriate restoration goals, and evaluating the efficacy of restoration efforts. We tested a straightforward classification scheme of Smallmouth Bass populations in least impacted non-wadeable rivers in Wisconsin based on parameters related to substrate and geographic location as both variables have been associated with relative Smallmouth Bass density. Coarse-substrate rivers tended to have higher Smallmouth Bass catch per effort values than fine-substrate rivers and southern rivers tended to have higher catch per effort values than northern rivers in Wisconsin. We used the expected Smallmouth Bass relative density estimates to assess the level of impairment of Smallmouth Bass populations in three Areas of Concern in Wisconsin (Milwaukee River and Estuary, Sheboygan River and Estuary, and the Fox River and Green Bay). We found that Smallmouth Bass catch per effort values were significantly higher in Areas of Concern than both the minimum and 25th percentile values for least-impacted rivers and were not significantly different from the median least-impacted values. Based on abundance, it does not appear that Smallmouth Bass populations are particularly impaired in these three Areas of Concern. © 2014 Copyright © 2014 AEHMS.

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