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Fishing elevates variability in the abundance of exploited species
Nature, 2006The separation of the effects of environmental variability from the impacts of fishing has been elusive, but is essential for sound fisheries management. We distinguish environmental effects from fishing effects by comparing the temporal variability of exploited versus unexploited fish stocks living in the same environments.
Hsieh, C. H. +5 more
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Acoustical measurement of fish abundance
The Journal of the Acoustical Society of America, 1990The theory of echo formation provides formulas relating echo energy to physical characteristics of the target. Single-target theory (applicable to counting isolated fish) is extended to the multiple-target case relevant to schooling fish. An echo-integrator equation relates fish density to echo energy integrated over a time gate corresponding to the ...
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Evaluating impacts of forage fish abundance on marine predators
Conservation Biology, 2021Abstract Forage fish—small, low trophic level, pelagic fish such as herrings, sardines, and anchovies—are important prey species in marine ecosystems and also support large commercial fisheries. In many parts of the world, forage fish fisheries are managed using precautionary principles that target catch limits below the maximum ...
Christopher M. Free +2 more
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Abundance of Fish, Source of Fat
Zeitschrift für Assyriologie und vorderasiatische ArchäologieAbstract Fish was an important natural resource in Lower Mesopotamia. The ancient inhabitants could easily rely on the nutrients and fats derived from fishes abundant in the diverse aquatic biomes of its rivers, lakes, marshes and the gulf.
Angela Greco, Nadja Pöllath
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Abundance, composition, and potential intake of microplastics in canned fish
Marine Pollution Bulletin, 2020The existence of microplastics (MPs) in canned fish (tuna and mackerel) samples was investigated and their composition, possible sources and potential intake were assessed. Light and fluorescence microscopy were used for the quantification of potential MPs.
Razegheh Akhbarizadeh +5 more
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Acoustic Techniques for Estimating Fish Abundance
IEEE Transactions on Geoscience Electronics, 1972Echo counting and echo integration are two acoustic techniques for estimating the abundance of fish stocks. Mathematical models for the echo counting and echo integrating systems are presented and analyzed. Expressions for the mean squared errors of the abundance estimate obtained with each system are obtained.
J. E. Ehrenberg, D. W. Lytle
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Statistical Power of Trends in Fish Abundance
Canadian Journal of Fisheries and Aquatic Sciences, 1987Estimation errors inherent in stock assessment methods may make it difficult to estimate time trends in fish abundances correctly. Our objective was to quantify the probability that trends in abundance of recruits will be successfully identified. For this analysis, we used an empirically based simulation model of English sole (Parophrys vetulus) off ...
Randall M. Peterman, Michael J. Bradford
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Climate change: Large-scale abundance shifts in fishes
Current Biology, 2021Warming seas are driving a mass-scale restructuring of marine life, with observed responses expanding beyond species' range shifts. New evidence highlights large regions where ecological change has been dominated by the declining abundance of species that prefer cooler waters.
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Dominance in Fishes: The Relation Between Environment and Abundance
Science, 1982Changes in abundance of dominant species of fish were positively correlated with environmental factors that improved survival, and abundance of the subordinate species was negatively correlated with the same factors. When dominance changed, the responses of both the dominant and subordinate species also changed. Implicit in this inverse relation is the
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Effect of Desalination Discharge on the Abundance and Diversity of Reef Fishes
Environmental Science & Technology, 2019Global growth in desalination industries has increased the need for an evidence-based understanding of associated environmental impacts. We completed a seven-year assessment of the responses of fish assemblages to hypersaline discharge from the large Sydney Desalination Plant.
Brendan P. Kelaher +3 more
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