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Kevin Johnson

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The Lake St. Clair delta (??? 100??km2) provides an important refuge for native freshwater mussels (Unionidae) wherein 22 of the ??? 35 historical species co-occur with invasive dreissenids. A total of 1875 live unionids representing 22 species were found during snorkeling surveys of 32 shallow (??? 1??m) sites throughout the delta. Richness and density of unionids and zebra mussel infestation rates varied among sites from 3 to 13 unionid species, 0.02 to 0.12 unionids/m2, and < 1 to 35 zebra mussels/unionid, respectively. Zebra mussel infestation of unionids in the delta appears to be mitigated by dominant offshore currents, which limit densities of zebra mussel veligers in nearshore compared to offshore waters...
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The physiological effects of episodic pH fluctuations on Atlantic salmon Salmo salar smolts in eastern Maine, U.S.A., were investigated. During this study, S. salar smolts were exposed to ambient stream-water chemistry conditions at nine sites in four catchments for 3 and 6 day intervals during the spring S. salar smolt migration period. Plasma chloride, plasma glucose, gill aluminium and gill Na+- and K+-ATPase levels in S. salar smolts were assessed in relation to ambient stream-water chemistry during this migration period. Changes in both plasma chloride and plasma glucose levels of S. salar smolts were strongly correlated with stream pH, and S. salar smolt mortality occurred in one study site with ambient stream...
Categories: Publication; Types: Citation; Tags: Journal of Fish Biology
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Protecting the nation’s natural and cultural resources and landscapes is essential to sustaining our quality of life and economy. Native fish and wildlife species depend on healthy rivers, streams, wetlands, forests, grasslands and coastal areas in order to thrive. Managing these natural and cultural resources and landscapes, however, has become increasingly complex. Land use changes and impacts such as drought, wildfire, habitat fragmentation, contaminants, pollution, invasive species, disease and a rapidly changing climate can threaten human populations as well as native species and their habitats. Landscape Conservation Cooperatives (LCCs) are public-private partnerships that recognize these challenges transcend...
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The Wyoming Game and Fish Department (WGFD) first developed a stream classification system in 1961. The inaugural system was intended to identify and rank the most important coldwater recreational fisheries to the State. Over time the system was also used to assess the relative potential impacts of proposed development projects to streams. The system also was adapted as one component in a land use management program to assess the relative value of properties being considered for acquisition by WGFD. The stream ranking protocol was periodically modified over the years. In its present form, streams are ranked using a combination of scores for productivity, accessibility and esthetics. In recent years, fisheries...
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