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Showing 1 to 20 of 153 for “"fish populations"”.
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Mechanistic models of recruitment variability in fish populations.
… worldwide about the decline of exploited fish stocks. The number of fish larvae surviving to be recruited into the adult population each year is fundamental to the long-term stability of a fish stock. Monitoring and predicting recruitment is a crucial component of managing economically …
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Fish Populations of Two Small Impoundments in Northeastern South Dakota
<p>Thirteen species and large standing crops of fish were found in Blue Cloud Abbey Pond and Labolt Pond, South Dakota. Adult population was estimated to be 5184 fish in Abbey Pond and 5016 in Labolt Pond. Composition of the populations differed. Black crappies were most numerous in Abbey Pond; …
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Bayesian hierarchical approaches to analyze spatiotemporal dynamics of fish populations
The study of spatiotemporal dynamics of fish populations is important for both stock assessment and fishery management. I explored the impacts of environmental and anthropogenic factors on spatiotemporal patterns of fish populations, and contributed to stock assessment and management by …
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Flood pulse influences on exploited fish populations of the Central Amazon
… influence the population dynamics and catches of fishes from river-floodplains. Although different measures of flood pulses, here called flood pulse variables, have been correlated to changes in catches of river-floodplain fishes, the flood pulse variables that have the strongest relationships to …
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Interaction between anglers and coarse fish populations in two gravel-pit lakes
The population biology of the coarse fish species in two gravel-pit fisheries (A and B) in Suffolk were studied from 1974 to 1977. Simultaneously the fish caught by anglers and their angling technique were monitored by census. Environmental factors were recorded on each census occasion and the …
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Applications of fish scale analysis to understand growth dynamics of fish populations
… to derive ecological information about fish populations is a fundamental tool in fisheries assessment, specifically the back-calculation of fish lengths. This study highlights the potential errors associated with correction factors (c) because of poor sampling and provides a validation …
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Understanding links between flow regime and fish populations in the Saskatchewan River Delta
… are essential to maintain sustainable fish populations. Abiotic environmental conditions can influence recruitment and the resulting ability to harvest adult fish. In rivers, the flow regime dictates water depths and velocities that subsequently trigger spawning and enable the survival …
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A test of the variable nature of density-dependent mortality in fish populations
… on the impact of impingement and entrainment of fish in power-plant cooling systems was questioned. Density-dependent dynamics were hypothesized as variable, not constant, making previous analyses based on constant density-dependent or density-independent mortality in error. This hypothesis was …
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Effects of Predation by Cormorants and Gars on Fish Populations of Ponds in Illinois
Made available in DSpace on 2014-12-04T22:45:56Z (GMT). No. of bitstreams: 1 0015201.pdf: 6188134 bytes, checksum: 84edd8ee62ba258a4dfabbd5cadc8ff9 (MD5) Previous issue date: 1955
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Forage Fish Populations and Growth of Muskellunge in a South Dakota Power Plant Cooling Reservoir
… age, growth, and impingement loss of forage fishes and the growth rate and impingement loss of muskellunge (Esox masquinongy) were studied to evaluate the use of the Big Stone Power Plant cooling reservoir as an area for rearing and holding muskellunge brood stock. There were 18 species of …
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Implications of small-scale run-of-river hydropower schemes on fish populations in Scottish streams
… by numerous authors who consider the impacts on fish and other biota as significant, particularly on salmonid fish populations in relation to migration.This study investigated the implications of small-scale run-of-river hydropower schemes on fish populations in Scottish streams. In these …
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Patterns of Historical and Contemporary Distribution and Occurrence of Imperiled Fish Populations in East Texas Streams
<p>East Texas supports a very diverse freshwater fish fauna, yet many of these species are listed as Species of Greatest Conservation Need (SGCN). In this study, I investigated historical and contemporary distribution trends of ten fish species listed as SGCN within the Neches, Sabine, and Cypress …
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Effects of Artificial Reef Implementation on Fish Populations in a Marine Protected Area: Bluefields Bay, Jamaica
Severe overfishing has presented a substantial dilemma in Jamaica. The fish populations within the country's boundaries have been decimated over an extensive period of time. Neighboring Caribbean countries use Jamaica as a worst case scenario as far as fisheries management is concerned. To …
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The Effect of Grass Carp Introduction on Aquatic Vegetation and Existing Fish Populations in Two Small Prairie Lakes
… also in South Dakota. Stocking densities were 49 fish/hectare and 61 fish/hectare (229 mm mean total length) in Prior Lake and East Lake Eureka, respectively. The biomass of prey fish in East Lake Eureka in 1986 was quite high with 88.3, 85.3 and 17.3 kg/hectare for black bullhead (Ictalurus …
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Seasonal Variation in Sampling Indices for Fish Populations Collected From the Missouri River Below Fort Randall Dam, South Dakota
… data have been documented for many sport fishes in lentic environments. To determine if similar influences occur with native riverine species in lotic systems, I selected two study sites within the riverine reach of Lewis and Clark Reservoir, South Dakota. Gill nets and electrofishing were …
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Changes in the invertebrate populations, fish populations, and water chemistry of a small stream above and below two impoundments
… and biomass of benthic macroinvertebrates and fish, and changes in drift patterns below the ponds. The energy dynamics alterations may have also influenced competitive interactions among benthic organisms and fish. The direct influence of physiochemical alterations appeared to be masked by …
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Effects of repetitive electroshocking on fish populations in experimental raceways and a small headwater stream in southern West Virginia
Fisheries scientists have utilized electrofishing extensively to sample and assess aquatic populations. The physiological responses of fish exposed to electroshock ranges from sensory recognition, through electrotaxis and electronarcosis, to death. This study examined the effects of repetitive …
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The Effects of Minimum Size Limit Regulations On Exploited Fish Populations off the Atlantic Coast of the Southeastern United States
<p>The commercial snapper-grouper fishery off the Atlantic coast of the southeastern United States contains many exploited species that are managed with species-specific regulations, though primarily managed with minimum size limits. Minimum size limits vary by species and are intended to protect …
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