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The practice of catch-and-release fishing has been widely promoted by angling fraternities as a fisheries manage- ment tool. The aim of this investigation was to determine the physiological response of Orange-Vaal smallmouth yellowfish, Labeobarbus aeneus, to catch-and-release angling in the Vaal River, South Africa. Fish were collected using standard fly-fishing techniques, anaesthetised in clove oil and blood was drawn from the caudal vein; thereafter the fish were weighed, measured, revived and released. Blood plasma was analysed for concentra- tions of glucose, cortisol and lactate to determine the effects of angling duration, fish size and water tempera- ture. Larger fish were angled for a longer duration compared with smaller fish. Levels of glucose were affected by water temperature (influenced by time of year). Plasma glucose concentrations decreased with greater angling duration. Few individuals (n = 12) showed increased plasma cortisol concentrations. In extended-capture fish (angled for >1 min), lactate concentrations increased significantly above values for rapid-capture fish (angled for >30 s). These data suggest that catch-and-release causes physiological stress to fish, but nonetheless this practice can be a valuable fisheries management tool to ensure the sustainability of fish populations. Other factors beyond the ‘angling’ time are likely to contribute to physiological disruptions in homeostasis and therefore handling and air exposure of angled fish should be included in future catch-and–release angling studies. In addition, the longer-term impact of angling on fish health should also be determined. 相似文献
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Benefits of repeated stocking with adult,hatchery‐reared brown trout,Salmo trutta,to recreational fisheries? 总被引：1，自引：1，他引：0
Abstract Recaptures of adult, hatchery-reared, brown trout, Salmo trutta L., and fishing time from anglers were used to evaluate the benefits of stocking programmes with repeated releases of adult brown trout. The recapture rate varied between 17% and 29%. The time between stocking and capture (referred to as residence time) varied between 1 and 160 days (median 3–49 days). Between 67% and 84% of trout caught in the river were recently released fish. Fishing effort increased after stocking, thereby increasing the impact of angling on wild stocks. Stocking with adult brown trout decreases the impact of angling on wild trout only if the time spent fishing by all anglers is kept stable. Furthermore, because of the short residence time of stocked trout, long-term impacts through competition for space and food, or genetic impact through introgression, are limited. 相似文献
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The relationship between growth in white crappie, Pomoxis annularis Rafinesque, and climate, lake morphometry and population density was studied in 103 Texas reservoirs. Growth of age‐0 through age‐3 white crappie was significantly (P≤0.05) related to latitude, growing season and surface area. Growth of age‐1 through age‐5 white crappie also was related to annual precipitation. Multiple linear regression models with precipitation and mean catch per unit effort (CPUE) of white crappie as independent variables explained 14–22% of the variation in growth of age‐0, ‐1 and ‐2 white crappie. By contrast, growth of age‐3, ‐4 and ‐5 white crappie was unrelated to CPUE. Apparently, between age 2 and 3, the density of white crappie in Texas reservoirs falls below a density‐dependent growth threshold beyond which growth is no longer related to density. This density‐dependent threshold was most likely related to angler harvest of larger, older white crappie. 相似文献
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M. F. O'Connell 《Fisheries Management and Ecology》2003,10(4):201-208
Conservation spawning requirements (limits) for Atlantic salmon, Salmo salar L., have been developed for a number of rivers in Newfoundland. Status of stocks is evaluated against these limits and scientific advice and recommendations on levels of recreational catch provided to resource managers. A critical factor in this process is the determination of total returns. This has been accomplished for 30–40% of the rivers in question over the years through the use of fish counting fences and traps installed in fishways. In Newfoundland, it is not logistically or financially possible to operate fish counting facilities in all of the approximately 200 Atlantic salmon rivers. Thus angling catch data have been used as an alternative means of estimating total returns to rivers without counting facilities. Estimates of total returns were three to four times higher than the actual values for one of the two rivers studied and deviated from the actual by as much as 60% for the other. Management implications of the approach are discussed. 相似文献
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Abstract An in‐depth explanation of selected content of the European Inland Fisheries Advisory Commission’s ‘Code of Practice for Recreational Fisheries’ (CoP) is presented. The focus is on core areas that were intensely debated in the drafting the CoP. These include definition of recreational fishing, recreational fishing practices, fish welfare, recreational fisheries management and research. It is anticipated that the CoP for recreational fisheries promotes best practice and management principles for sustainable recreational fisheries, within the recreational fisheries sector and ancillary industries/sectors regionally, nationally, and ultimately globally. To be viable, the CoP for recreational fisheries must be adopted by the international community complementing the Code of Conduct for Responsible Fisheries of the Food and Agriculture Organization of the United Nations. 相似文献
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Thomas M. Detmer Kyle J. Broadway Joseph J. Parkos Matthew J. Diana David H. Wahl 《Fisheries Management and Ecology》2020,27(5):540-543
Tournament fishing has risen in popularity over the last half a century. As such, social and financial incentives combined with technological advancements are expected to drive changes in angler's capacity to exploit tournament‐eligible fish stocks, as has been observed in commercial fisheries. The aim of this study was to quantify temporal trends in angler efficiency and their ability to exploit a given fish stock relative to effort in largemouth bass fishing tournaments. A collective analysis across seven Illinois reservoirs comparing change through time in angler catch rates and relative population abundances indicated that angler efficiency has generally improved through time. For the decade from 2005 to 2015, a greater than threefold increase in the efficiency of anglers to exploit a static population of largemouth bass was estimated. Anglers have become more efficient at exploiting populations, which is likely to influence management decisions in the future, particularly in harvest‐orientated fisheries and those reliant upon fishery‐dependent surveys. 相似文献
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Joseph W. Watson Kieran Hyder Robin Boyd Robert Thorpe Marc Simon Weltersbach Keno Ferter Steven J. Cooke Shovonlal Roy Richard M. Sibly 《Fish and Fisheries》2020,21(5):1034-1045
Fish are increasingly exposed to anthropogenic stressors from human developments and activities such as agriculture, urbanization, pollution and fishing. Lethal impacts of these stressors have been studied but the potential sublethal impacts, such as behavioural changes or reduced growth and reproduction, have often been overlooked. Unlike mortality, sublethal impacts are broad and difficult to quantify experimentally. As a result, sublethal impacts are often ignored in regulatory frameworks and management decisions. Building on established fish bioenergetic models, we present a general method for using the population consequences of disturbance framework to investigate how stressors influence ecologically relevant life processes of fish. We partition impact into the initial energetic cost of attempts to escape from the stressor, followed by the energetic impacts of any injury or behavioural change, and their consequent effects on life processes. As a case study, we assess the sublethal effects of catch and release angling for the European sea bass (Dicentrachus labrax, Moronidae), a popular target species for recreational fishers. The energy budget model described is not intended to replace existing experimental approaches but does provide a simple way to account for sublethal impacts in assessment of the impact of recreational fisheries and aid development of robust management approaches. There is potential to apply our energy budget approach to investigate a broad range of stressors and cumulative impacts for many fish species while also using individual‐based models to estimate population‐level impacts. 相似文献
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Quantitative estimates of freshwater fish stocking practices by recreational angling clubs in France
Julien Cucherousset Rémy Lassus Carsten Riepe Paul Millet Frédéric Santoul Robert Arlinghaus Mathieu Buoro 《Fisheries Management and Ecology》2021,28(4):295-304
Although freshwater fish stocking is widely used by managers, quantitative assessments of stocking practices are lacking in many countries. The general objective of the present study was to determine the quantity and characteristics of fish stocking in metropolitan France. Using a survey-based approach, stocking practices for 2013 by recreational angling clubs in France were quantified, which represented the bulk of fish stocking undertaken in that year. Stocking was found to be practiced by 88.6% of angling clubs in France, representing, on average, 65% of their annual budget. Overall, 22 species were stocked, including 13 native and nine non-native species, with strong variations among species in terms of life stages and body sizes used for stocking. Using Bayesian modelling, a total biomass of 2.029 t, representing approximately 90 million fishes, was estimated to be stocked in France in 2013. In terms of biomass, the most widely stocked species were rainbow trout Oncorhynchus mykiss (Walbaum), brown trout Salmo trutta L., roach Rutilus rutilus (L.), common carp Cyprinus carpio L. and northern pike Esox lucius L. A stocking volume of approximately 60 fishes or 1.5 kg of fish biomass per angler per year seems commonplace in industrialised countries for which data are available. 相似文献
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