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Full-Text Articles in Aquaculture and Fisheries
Influence Of Physiochemical And Watershed Characteristics On Mercury Concentration In Walleye, Sander Vitreus, M., Cari-Ann Hayer, Steven R. Chipps, J. J. Stone
Influence Of Physiochemical And Watershed Characteristics On Mercury Concentration In Walleye, Sander Vitreus, M., Cari-Ann Hayer, Steven R. Chipps, J. J. Stone
Natural Resource Management Faculty Publications
Elevated mercury concentration has been documented in a variety of fish and is a growing concern for human consumption. Here, we explore the influence of physiochemical and watershed attributes on mercury concentration in walleye (Sander vitreus, M.) from natural, glacial lakes in South Dakota. Regression analysis showed that water quality attributes were poor predictors of walleye mercury concentration (R2 = 0.57, p = 0.13). In contrast, models based on watershed features (e.g., lake level changes, watershed slope, agricultural land, wetlands) and local habitat features (i.e., substrate composition, maximum lake depth) explained 81% (p = 0.001) …
Match- Mismatch Regulation For Bluegill And Yellow Perch Larvae And Their Prey In Sandhill Lakes, Jeffrey C. Jolley, David W. Willis, Richard S. Holland
Match- Mismatch Regulation For Bluegill And Yellow Perch Larvae And Their Prey In Sandhill Lakes, Jeffrey C. Jolley, David W. Willis, Richard S. Holland
Natural Resource Management Faculty Publications
Food availability may regulate fish recruitment, both directly and indirectly. The availability of zooplankton, especially to newly hatched larvae, is thought to be crucial to their early growth and survival. We examined stomach contents of larval bluegill Lepomis macrochirus and yellow perch Perca flavescens in Pelican Lake and Cameron Lake, Nebraska, in 2004 and 2005. We also determined zooplankton availability and calculated prey selection using Chesson’s a. In addition, we investigated potential match–mismatch regulation of recruitment from 2004 to 2008. Bluegill positively selected copepod nauplii and Bosmina spp., and yellow perch often selected copepods. Abundant zooplankton populations were available for …
Twin Screw Extrusion Of Ddgs-Based Aquaculture Feeds, S. Kannadhason, Kurt A. Rosentrater, K. Muthukumapappan, Michael L. Brown
Twin Screw Extrusion Of Ddgs-Based Aquaculture Feeds, S. Kannadhason, Kurt A. Rosentrater, K. Muthukumapappan, Michael L. Brown
Natural Resource Management Faculty Publications
Six isocaloric (3.65 kcal/g), isonitrogenous (35% dry-basis [db] protein), ingredient blends were prepared with 0, 17.5, 20, 22.5, 25, and 27.5% distiller’s dried grains with solubles (DDGS) and other ingredients (soybean meal, corn, fish meal, whey, soybean oil, vitamin and mineral mix). The blends were moisture balanced to 15% db, then extruded in a twin screw extruder using a 2 mm die at 190 rpm, and a 3 mm die at 348 rpm. Analyses of the extrudates included moisture content, expansion ratio, unit density, bulk density, sinking velocity, color (L*, a*, and b*), water absorption, water solubility, and pellet durability …
The Influence Of Didymosphenia Geminate On Fisheries Resources In Rapid Creek, South Dakota – An Eight Year History, D.A. James, S.R. Chipps
The Influence Of Didymosphenia Geminate On Fisheries Resources In Rapid Creek, South Dakota – An Eight Year History, D.A. James, S.R. Chipps
Natural Resource Management Faculty Publications
The aquatic nuisance diatom Didymosphenia geminata was established in Rapid Creek in the Black Hills of South Dakota in 2002. Shortly thereafter, large declines (>50%) of the naturalized brown trout Salmo trutta population were observed. We evaluated the influence of water resources and D. geminata on (1) declines in brown trout biomass, (2) changes in food resources, and (3) diet of brown trout in Black Hills streams. Drought conditions were largely responsible for trout declines in Black Hills streams. However, comparison of brown trout sizestructure between the pre-D. geminata and post-D. geminata periods revealed that juvenile brown …