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Chile has a long history of restocking, stock enhancement, and translocation to support artisanal or small-scale fisheries; however, these programs have been scarcely discussed in the scientific literature. Here, we present a review of previous initiatives and discuss specific areas for future progress. We identified 204 releases across 117 different areas, involving 7 taxonomic groups and 22 species (20 marine and 2 freshwater). Marine stocking mainly occurred within the context of the spatial framework through which artisanal fisheries are managed [Management and Exploitation Areas for Benthic Resources (MEABR)], and over 60% involved translocation of wild individuals rather than release of hatchery-reared seed. While “stock enhancement” was the primary intention for most releases, it is unclear whether depleted spawning biomass or other recruitment limitations were the primary motivation, and few projects reported more than one stocking event. The echinoid Loxechinus albus and the gastropod Concholepas concholepas were the main target species. Only 6% of projects examined reported positive results that could be linked to releases, and none reported the use of tagging or analysis of costs or benefits. There are several areas for targeted development that should improve the social and economic outcomes from marine stocking activities. This synthesis provides a snapshot of marine stocking in Chile to date and highlights opportunities that are relevant to both Chile and other nations with substantial small-scale fisheries.

Introduction: Cryphiops caementarius, is an endemic prawn from river ecosystems in Southern Perú and Northern Chile. In these watersheds, natural populations are threatened by multiple anthropic interventions such as mining activities and fishing pressure, but also, by increasing impacts of invasive exotic predators. Information related with predation on C. caementarius is scarce representing a major knowledge gap to ensure suitable management and conservation practices. Accordingly, the further deepening in relevant aspects such as the estimation of populations losses due to predators has been indicated as critical by relevant agencies as FAO. Objective: To conduct a complete registry and classification of C. caementarius predators, updating the knowledge for the Andean region. Methods: A thorough bibliographic review on existing information on C. caementarius' predators from Perú and Chile was carried out calculating percentage of occurrence, relative frequency of species, zoogeographic origin, trophic structure, phenotypic attributes, river zone that inhabits and life stage of incidence. The registry was complemented using semi-structured interviews from prawn´s fishers in central-Northern Chile. Results: C. caementarius is predated along the entire fluvial network (estuary, potamon and rhithron) by 21 species of opportunists, carnivores, omnivores and herbivores, mostly aquatic vertebrates. In turn, these belong to 15 families and six guilds of native, exotic and cosmopolitan species. Approximately 86 % predate on adult prawns, whilst, 71 % on juveniles and 24 % on larvae. More than 40 % of the predation pressure seems to be exerted by native waterfowls and 24 % by exotic fish. Conclusions: The results emphasize the relevance for conservation of native species of predators in the Andean region and the need of control measures on exotic species in a latitudinal basis. Accordingly, this review may serve as an initial decision-making tool for future conservation efforts both on prawns and native biota, but also supporting restocking actions, fisheries management plans and risk assessment for C. caementariuspopulations across the Andean region.

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