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Showing 1 to 20 of 48 for “"fishing pressure"”.
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Demography of Alligator Snapping Turtles (Macrochelys Temminckii) Along a Fishing Pressure Gradient
<p>Passive fishing gear is a threat to the alligator snapping turtle (<em>Macrochelys temminckii</em>). The spatio-temporal persistence of this threat and its impacts on <em>M. temminckii</em> populations has not been quantified. I quantified the density of passive fishing gear and the demographic …
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A Spatial Analysis of Changes in Recreational Fishing Pressure on the Central Coast of California Subsequent to MPA Implementation
… but few studies assess how MPAs affect regional fishing patterns. Previous research suggests effort will intensify at MPA edges, but few datasets include sufficient pre-implementation data to quantify how MPAs alter fishing effort. We used recreational fisheries data collected by scientific …
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Tracking African penguins (Spheniscus demersus) outside of the breeding season: Regional effects and fishing pressure during the pre-moult period
… sagax). This shift may be exacerbated by pressure from the small-pelagic fishery targeting these species. A lack of knowledge regarding foraging areas when not breeding has been identified as a deficiency in management planning for African penguins. Satellite transmitters were deployed on …
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Changes in food web structure and energy flow in kelp forest ecosystems on the south-west coast of South Africa following the invasion of Jasus lalandii
… between the two different states and assess how fishing pressure may have driven the shift in ecosystem state. Using the baseline models, different fishing management strategies were tested to see whether the post lobster-invaded ecosystem could be shifted back or close to the pre-invasion state. …
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Updated life history and population structure assessment of spiny dogfish, Squalus acanthias, in the Gulf of Maine
… ten-fold increase in fishery landings. Because fishing pressure has been shown to affect population dynamics in targeted species, an update of previous life history parameters is warranted to effectively manage the population. Although updated and accurate life history parameters are important, …
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Results and Evaluation of An Aerial Creel Survey Technique On Lake Sharpe, South Dakota
… An aerial fisherman count was used to estimate fishing pressure and an angler interview survey was used to estimate catch rates, mean party size, mean fisherman day, and residence of the anglers. The results of the two surveys were combined to estimate harvest. The separate surveys were combined …
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Comparisons of Fish Species Inside and Outside of Marine Protected Areas off the South Central Coast of California
… that have experienced different degrees of fishing pressure. Big Creek MPA has been closed to all fishing from 1993 onwards and is the farthest from port of all locations. Cambria lies closest to port of the three locations and because of this has the highest fishing pressure. Piedras …
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Investigating single and multiple species fisheries management: stock status evaluation of hammerhead (Sphyrna spp.) sharks in the western North Atlantic Ocean and Gulf of Mexico
… with maximum sustainable yield (MSY)), and overfishing (fishing level above that associated with MSY) occurred in 2005. We found that scalloped hammerhead shark population recovery is likely to occur within 10 years if catch remains at or below 2005 levels. Great and smooth hammerhead sharks …
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Spatial management of groundfish resources in the Gulf of Maine and Georges Bank
… the marine environment, studies suggest that overfishing suppresses sustainability and resilience in fish populations. In the 1990s, the National Marine Fisheries Service (NMFS) implemented five large year-round fishery closures in the Gulf of Maine and Georges Bank. These closures are partially …
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Population Dynamics of Sheepshead (<i>Archosargus probatocephalus;</i> Walbaum 1792) in the Chesapeake Bay Region: A comparison to Other Areas and an Assessment of Their Current Status
<p>Sheepshead recently have seen an increase in fishing pressure in Virginian waters of the Chesapeake Bay. This increase in fishing pressure has led to demands to install effective management measures to protect the fishery. However, no study regarding the population dynamics, and thus potential …
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The biology, ecology and population trends of jacopever Helicolenus dactylopterus in South Africa
… it is difficult to understand its response to fishing pressure. The life history, habitat preference and population trends of the species in South Africa were thus investigated. The age, growth, reproductive characteristics and diet were examined from 719 specimens collected from west and south …
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Angler Harvest Survey of Lake Francis Case, South Dakota
… aerial angler count was used to estimate angle pressure, and an angler interview survey was used to estimate catch rate. In 1981, a section of Lake Francis Case in the vicinity of the Gregory County Pump Storage Project (Zone 2) was surveyed. IN 1982, the survey was expanded to include the …
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Settlement patterns, biology and collection of pueruli and early juveniles of the West Coast rock lobster Jasus lalandii
… increase production, and potentially relieve fishing pressure and enhance natural populations through reseeding areas with cultured lobsters. Postlarval lobsters are, however, not yet available in sufficient quantities through culture from egg to puerulus, so postlarvae for ongrowing need to …
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The biology, distribution and ecology of Lampanyctodes hectoris and Maurolicus muelleri along the South-African coast
… of these two species before possible commercial fishing pressure brings about a change in these parameters. Samples of L. hectoris taken from commercial catches and research cruises, and samples of M. muelleri obtained from research cruises were analysed to obtain the biological parameters. L. …
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Drivers of eco-evolutionary dynamics in model systems - the role of harvest mortality and intraspecific competition
Populations exist under a range of selective pressures, and the relative importance of natural (e.g. environmental change) and anthropogenic pressures (e.g. fishing mortality) remains hotly contested. Such external pressures can affect a population directly – for example when environmental change …
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Great white sharks Carcharodon carcharias in Gansbaai, South Africa : environmental influences and changes over time, 2007-2011
… protective legislation prohibiting targeted fishing of the great white shark Carcharodon carcharias in 1991. This pre-emptive measure was intended to protect this species from increasing fishing pressure to allow researchers to gather information of this shark’s distribution, basic life …
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Assessment of the Effects of Habitat, Harvest and Community Interactions on the Abundance of Walleye Sander Vitreus in Inland Lakes Throughout Ontario
… in a multiple regression. Fish community and fishing pressure were significant predictors in explaining walleye abundance (adjusted R2=0.45, p<0.001). The presence of bluegill (Lepomis macrochirus) and smallmouth bass (Micropterus dolomeiu) were significant negative predictors in the top model …
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Evaluating Alternate Management Strategies for Spotted Seatrout (<i>Cynoscion nebulosus</i>) in the North-Central Gulf of Mexico
… nebulosus</em>) receive considerable fishing pressure as the most popular saltwater target species in the north-central Gulf of Mexico. The potential for alternate management strategies, including stock enhancement and reducing discard mortality, to support the sustainability of the …
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Analysis of catchable trout fisheries management by computer simulation
… and functions which generate predictions of fishing pressure on a particular fishery. To evaluate the effect of each system component, CATS was exercised over a wide range of potential system component alterations. Predominant stocking of brook trout appreciably increased average catch per …
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