Results 271 to 280 of about 216,251 (304)

Model of Fish Biomass Dynamics

Transactions of the American Fisheries Society, 1974
Abstract A model of fish biomass dynamics is developed based on principles of physiology, population biology, and trophic ecology. The model is designed to incorporate measurable parameters for simulating seasonal changes in a natural population. All parameters were implemented for the bluegill (Lepomis macrochirus) and simulation results compared with
James F. Kitchell, Joseph F. Koonce, John J. Magnuson, Robert V. O'Neill, Herman H. Shugart, Ray S. Booth   +5 more
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Empirical Prediction of Fish Biomass and Yield

Canadian Journal of Fisheries and Aquatic Sciences, 1982
Data taken from the literature were used to develop and compare predictors of fish biomass and yield in lakes. Two new indices, total phosphorus concentration and macrobenthos biomass/mean depth, were the best univariate predictors offish yield (r2 = 0.84 and r2 = 0.48, respectively) and biomass (r2 = 0.75 and r2 = 0.83, respectively) for four ...
John Mark Hanson, William C. Leggett
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Prediction of biomass in Norwegian fish farms

Canadian Journal of Fisheries and Aquatic Sciences, 2011
We have constructed a statistical model to forecast, with uncertainty, the stock of Norwegian farmed Atlantic salmon ( Salmo salar ). The model provided good predictions of future biomass of Norwegian farmed salmon and can also be used to perform “what-if” analysis exploring the impact of varying scenarios for stocking and slaughtering.
Anders Løland, Magne Aldrin, Gunnhildur Högnadóttir Steinbakk, Ragnar Bang Huseby, Jon Arne Grøttum   +4 more
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The effects of fishing on the diversity, biomass and trophic structure of Seychelles’ reef fish communities

Coral Reefs, 1995
A fishery independent underwater visual census technique was used to assess the effects of fishing on the diversity, biomass and trophic structure of the diurnally active non-cryptic reef-associated fish communities of the Seychelles. One hundred and thirty four species associated with three significantly different types of reef habitat were censused ...
S. Jennings, E. M. Grandcourt, N. V. C. Polunin   +2 more
openaire   +1 more source

Biomass Model of Reservoir Fish and Fish-food Interactions, with Implications for Management

North American Journal of Fisheries Management, 1982
Abstract A mathematical model was developed to help evaluate trophic relations of fishes in reservoirs and to assess the effects of perturbations (e.g., reservoir operations, species introductions, stocking, and harvest) on reservoir ecosystems.
Gene R. Ploskey, Robert M. Jenkins
openaire   +1 more source

Effect of fish biomass on environmental DNA shedding and degradation

Molecular Biology Reports
Environmental DNA in freshwater samples is a promising tool for assessing the relationship between biomass and eDNA concentration. We performed a quantitative PCR in experimental tanks to verify the influence of density/biomass on the release and decay of DNA in water samples.The three densities used were one fish (0.416 ± 0.075 g L⁻¹), two fish (0.778 
Carlos Henrique dos Anjos dos Santos, Vilmar Biernaski, Adalberto Luis Val   +2 more
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Fish biomass size spectra in Chesapeake Bay

Estuaries, 2005
Biomass size spectra of pelagic fish were modeled to describe community structure, estimate potential fish production, and delineate trophic relationships in Chesapeake Bay. Spectra were constructed from midwater trawl collections each year in April, June–August, and October 1995–2000. The size spectra were bimodal: the first spectral dome corresponded
Sukgeun Jung, Edward D. Houde
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Biomass and Production of Fishes in Natural and Channelized Streams

Canadian Journal of Fisheries and Aquatic Sciences, 1986
Fish biomass and production were estimated at two channelized and two unchannelized stream sections. Biomass and total and available production were much lower in the channelized sections than in the natural sections. Regressions of the log of production versus the log of initial biomass had slopes significantly different from 1.
Cameron B. Portt, Eugene K. Balon, David L. G. Noakes   +2 more
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A Simple Biomass‐Based Length‐Cohort Analysis for Estimating Biomass and Fishing Mortality

Transactions of the American Fisheries Society, 2010
AbstractA biomass‐based length‐cohort analysis (LCA) was examined for its performance in estimating total stock biomass and fishing mortality (F) for a population in equilibrium. We compared two LCA methods—(1) a numbers‐based LCA that relies on catch numbers at length as input data and (2) a new biomass‐based LCA that relies on catch biomass at length—
Chang Ik Zhang, Bernard A. Megrey
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Improvement of fish length estimates for underwater visual census of reef fish biomass

Journal of Applied Ichthyology, 2015
Summary Accuracy and precision are of great importance in the assessment of reef fish biomass when conducting an underwater visual census (UVC). Quantification and subsequent correction of the bias is required in order to standardize the estimates and correct for underwater distortion.
I. Yulianto, C. Hammer, B. Wiryawan, S. T. Pardede, T. Kartawijaya, H. W. Palm   +5 more
openaire   +1 more source