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Density-dependent processes resulting from fish stocking were demonstrated to have a significant impact on recreational fishery performance, and this case study will be of use to guide fish stocking decisions in other fisheries. We evaluated a put-grow-and-take lake fishery stocking program for Chinook salmon (Oncorhynchus tshawytscha) located in south-western Victoria, Australia. We hypothesised that recreational fishery performance would show significant density-dependent relationships with fish stocking. To test this hypothesis, we used Wald F tests in a general linear regression model to evaluate relationships between a long-term historical fish stocking program and fishery performance, including angler and net catch rates and weight, length, and condition of caught fish. Our results yielded (i) significant positive relationships between angler and net catch rate of Chinook salmon with the number of Chinook salmon stocked in the same year and (ii) significant negative relationships between the weight of angler-caught Chinook salmon with both the number of Chinook salmon stocked in the same year and total number of fish stocked (apart from Chinook salmon) over the previous three year period. Il a deja ete demontre que les processus dependants de la densite qui resultent de l'empoissonnement ont une importante incidence sur le rendement des peches recreatives, et la presente etude de cas servira a orienter les decisions relatives a l'empoissonnement dans d'autres peches. Nous avons evalue un programme d'empoissonnement pour une peche de lac au saumon quinnat (Oncorhynchus tshawytscha) de type depot-retrait dans le sud-ouest de l'Etat de Victoria (Australie). Nous avons postule qu'il devrait y avoir des relations dependantes de la densite significatives entre le rendement de la peche recreative et l'empoissonnement. Pour verifier cette hypothese, nous avons utilise des tests F de Wald dans un modele de regression lineaire generale pour evaluer les liens entre un programme d'empoissonnement historique de longue duree et le rendement des peches, dont les taux de prises a la ligne et au filet, et le poids, la longueur et l'embonpoint des poissons peches. Nos resultats revelent (i) des relations positives significatives entre le taux de prises a la ligne et au filet de saumons quinnats et le nombre de saumons quinnats empoissonnes la meme annee et (ii) des relations negatives significatives entre le poids des saumons quinnats peches a la ligne et tant le nombre de saumons quinnats empoissonnes la meme annee que le nombre total de poissons empoissonnes (autres que des saumons quinnats) au cours des trois annees precedentes. [Traduit par la Redaction], Introduction Fish populations are subject to limited resources causing density dependence or density independence in vital rates of growth, mortality, and reproduction of individuals (hereafter density-dependent processes). Density-dependent processes in [...]

Fish stocking is commonly used in developed countries and aims to improve recreational fish stocks and rebuild threatened species populations. Fish stocking is often contentious due to its high investment, limited scientific evaluation, and typically divided opinion from key stakeholders. Debates over the efficacy and effects of fish stocking continue to occur in the absence of key information about current and past practices, and their degree of alignment with the accepted responsible approach previously published in platform papers. Consequently, using Australia as a case study, this paper presents a framework for assessing fish stocking practices. First, recent fish stocking practices were benchmarked by compiling freshwater fish stocking statistics from every state and territory in Australia. Over 84 million fish were found to have been stocked in Australia between 2009 and 2015, with recreational species, both native and salmonid, comprising the majority of numbers and weight of fish stocked, respectively. Second, historical trends in fish stocking were assessed over a 106 year period across one major jurisdiction, finding significant changes in practices including a strong move toward native species, and a reduction in the number of salmonids stocked, but an increase in size. Third, a literature review was conducted to evaluate Australia's fish stocking practices and found they could be generally considered responsible, however improvements could be made in areas highlighted. This study provides a valuable framework to assess fish stocking practices, aiding our understanding, informing future discussion, and fostering better outcomes from this popular fisheries management tool. [ABSTRACT FROM AUTHOR]