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21	The Impact of Environmental Conditions, Food Resources, and Ecological Stoichiometry in Structured Populations Showalter, Ann Marie 07 January 2016 (has links) No description available. Biology Aquatic Sciences Ecology Freshwater Ecology Limnology Organismal Biology ecological stoichiometry bluegill sunfish population structure damselfly food quality ontogeny gizzard shad nutrients elemental imbalance nitrogen phosphorus
22	Responses of Fishes to a Low pH Environment Prete, Philip J. (Philip John) 08 1900 (has links) Data were collected from natural and introduced fishes present in Ferndale Lake, a small (120 ha) sport fishing reservoir in Camp County, east Texas. Levels of pH measured in the lake during the study period ranged from 3.5 to 5.3. Monthly field surveys and experimental manipulations were designed to evaluate quantitatively the signs of stress at various biological levels. Lethal limits to low pH were quantified for largemouth bass (Micropterus salmoides) and bluegill (Lepomis macrochirus) to be pH 3.8 and 4.0,respectively. Mean blood pH (+ 1 SD) of 59 bluegill was 7.41 (j 0.16), with no significant difference (P-0.05) among groups from Ferndale Lake and Moss Lake (Cooke Co., Texas) under experimental conditions, even when severe stress was externally apparent. In a dual-trough horizontal pH gradient, bluegill behavioral avoidance was observed at pH levels below 7.0. Individual testing of 40 bluegill in pH gradient of 5.2 to 7.6 resulted in median occupation of pH 7.1,with an interquartile range of pH 6.9 to 7.3. Decreased community structure and population "well being" compared to early studies cannot be attributed entirely to recent acidic condition. Separating potential stress due to lake conditions from that due to heavy biotic predation by sport fishing in a small reservoir is difficult. fish population Fishes -- Effect of water quality on. Micropterus. Bluegill. Fishes -- Texas -- Ferndale Lake. sunfish reservoir ecology
23	The Effect of Dredging on Fish Communities in Agricultural Streams in Crawford, Sandusky and Seneca Counties of Ohio. Selden, Justin D. 27 November 2013 (has links) No description available. Agriculture Animals Aquaculture Aquatic Sciences Animal Sciences Biology Biostatistics Conservation Ecology Environmental Geology Environmental Science Environmental Studies Geology Geobiology Hydrology Natural Resource Management Organismal Biology Sustainability Wildlife Conservation Wildlife Management Zoology Agriculture fish community morphology stream ditch river shiner minnow darter sunfish chub stoneroller dace topminnow Shannon Diversity Simpson's Index IBI Index of Biotic Integrity Richness Abundance dredge coefficient of variation

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