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Showing 1 to 8 of 8 for “"Yield-per-recruit"”.
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Growth and Yield-Per-Recruit Modeling of Spot (<i>Leiostomus xanthurus</i>) in the Chesapeake Bay, and a Comparison of Biological Reference Points
… combination of M and K makes spot relatively impervious to growth overfishing as determined by yield-per-recruit modeling. Because spot are nearly impervious to growth overfishing, management thresholds based on yield-per-recruit modeling may be inappropriate. In addition, the combination of …
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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
… the population dynamics, and thus potential yield, of sheepshead has been conducted north of Cape Hatteras. We addressed the need for information regarding the population dynamics of Chesapeake Bay sheepshead by investigating their age distribution, growth rate and reproductive biology. We …
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Aspects of the biology and population dynamics of the deep-water commercially exploited crabs off South West Africa/Namibia
… The deep-sea red crab Geryon maritae forms >99 percent of the catch made by traps, the balance being a by-catch of stone crab Lithodes tropicalis. Historical information dating back to the late 1970's has been examined, but most of the data analysed in this study have been collected since 1980. …
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Modelling the relative impacts of trawling and longlining on Cape hake Merluccius capensis on the inshore Agulhas bank
… grounds of the Agulhas bank whereas longlines operate over rocky areas. Size comparisons of the catches of the two fishing methods reveal that longlines catch very few fish that are < 60 cm whereas trawl cataches are dominated by M. capensis of length < 60 cm. Analyses also revealed sex …
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Using Management Strategy Evaluation to address problems arising as a result of competing users of the South African horse mackerel resource
… putting it well above its Maximum Sustainable Yield (MSY) level. For the directed midwater fishery, MSY is estimated to be in the region of 50 000-100 000 tonnes per annum. However, the results of constant catch projections suggest that there is a pronounced yield-per-recruit effect, with even …
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Evaluation of Current Management Strategies for the New River, Virginia, Muskellunge Fishery: Modeling the Effect of Alternative Harvest Regulations and Habitat Selection
… and that is based on derived statistical properties of the Wr index. Abundance of memorable-length (³1,070 mm) muskellunge was predicted to increase with minimum length limits of 914, 1,016, and 1,143 mm. Although yield per recruit would decline under a 1,143-mm minimum length limit, it was …
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Spatial and temporal heterogeneity in life history and productivity trends of Atlantic Weakfish (Cynoscion regalis) and implications to fisheries management
… and maturity parameters then were applied to per-recruit analyses to examine the sensitivity of biological reference points to spatial and temporal variation in life history attributes (Chapter Three). Mixed-effects life history models incorporating spatial and temporal variation revealed …
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The value of catch statistics and records of Guano Harvests for managing certain South African Fisheries
… of juvenile hake C3 million metric tonnes per year or more, squid(> 0. 5 million metric tonnes per yearly, and midwater shoaling fish (together > 0. 5 million metric tonnes per year) is substantial compared to the total annual landing of marine fish off South Africa which is in the region …