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1	The Evolutionary Genetics of Campostoma anomalum and Campostoma oligolepis Merritt, Ronald L. 12 1900 (has links) Electrophoretic variation in 12 proteins encoded by 16 loci was analyzed to compare the genetic relationships of 18 natural populations representing two species of stoneroller minnows, Campostoma anomalum and C. oligolepis. Ten of the loci were monomorphic and fixed for the same allele in all populations of both species. One locus, Mdh-2, was found to separate both species. Mean heterozygosity for both species was 0.072. Estimates of levels of inbreeding indicated this phenomenon is operating in C. anomalum to structure the populations genetically. Mean genic identity (I) between the two species was high, 0.887, indicating the taxa are closely related. Nevertheless, data accumulated point to the conclusion that the two species maintain electrophoretic variation in 12 proteins encoded by 16 loci was analyzed to compare the genetic relationships of 18 natural populations representing two species of stoneroller minnows, Campostoma anomalum and C. oligolepis. Ten of the loci were monomorphic and fixed for the same allele in all populations of both species. One locus, Mdh-2, was found to separate both species. Mean heterozygosity for both species was 0.072. Estimates of levels of inbreeding indicated this phenomenon is operating in C. anomalum to structure the populations genetically. Mean genic identity (I) between the two species was high, 0.887, indicating the taxa are closely related. Nevertheless, data accumulated point to the conclusion that the two species maintain their genetic integrity throughout their ranges. their genetic integrity throughout their ranges. stoneroller minnows genetic relationships evolutionary genetics Fishes -- Evolution. Minnows.
2	USE OF IN-SITU FISH POPULATIONS FOR BIOMONITORING POLYCHLORINATED BIPHENYL AND METAL POLLUTION IN MODERATELY IMPACTED FRESHWATER STREAMS Price, David John 01 January 2007 (has links) Water, sediments, floodplain soils, and fish from Big and Little Bayou creeks were assessed for polychlorinated biphenyls (PCBs) and metals in 1987-2005. The streams were impacted by effluents from the Paducah Gaseous Diffusion Plant (PGDP). PCBs were rarely detected in water samples. Aroclor 1248 detections in sediments and floodplains were sporadic, but 1254 and 1260 were consistent. Seasonal variations were only observed for Aroclor 1248. Detection of PCBs in floodplains indicated recent influx of contaminated sediments. Species-specific PCB residues patterns were studied for Lepomis cyanellus, L. megalotis, L. macrochirus, and Campostoma anomalum. Highest PCB concentrations were found in stoneroller minnows. PCBs decreased over time in sunfish species, but retained a baseline level. No relationships were found between sunfish age and PCB concentrations. At low PCB levels, green sunfish body burden (BB) did not correlate with lipid content. A certain PCB concentration must be exceeded before PCB BB correlates with lipid content. Stream flows differed by season, and fish PCB BB differed by season, but stream flow did not correlate with fish BB. Congener groups corresponded to Aroclor concentrations. Higher chlorinated biphenyls peaked in the spring for sport fish. PCBs remobilized in the spring resulted in higher summer BB for the stoneroller minnows, whereas sunfish eliminated PCBs by summer. This variability was due to the sunfishs ability to regulate PCBs. Metal concentrations did not display the seasonal variability evident in the PCB data. Water metals may have peaked during storm events and decreased rapidly. Water Pb increased with time, but the source could not determined. Zinc in Little Bayou creek likely originated from the PGDP. Except for Cu and Zn, stoneroller minnow metal BB decreased with time. Metal BB were used to determine bioavailable fractions. Less than half of the water column Cd, Cr, Fe, and Pb in impacted areas were bioavailable to stoneroller minnows, whereas 59% of Ag, 73% of Cu, and 64% of Zn were bioavailable. Cumulative criterion units were calculated to determine additive metal impacts, and proved useful in locating sectors with possible ecological impact. In-situ monitors proved valuable in studying PCB and metal behavior under real-world conditions.
3	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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