Knowledge status of predators of the freshwater prawn Cryphiops caementarius (Decapoda: Palaemonidae) in river systems along the North Western Andean region from Perú and Chile

Abstract

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.

Camarones, camaroneros y escasez hídrica: desafíos para la sostenibilidad pesquera de Cryphiops caementarius en la cuenca semiárida del río Choapa, Chile

“…El camarón de río del norte Cryphiops caementarius es una palaemónido endémico de las cuencas hidrográficas de la región Andina de Perú y norte de Chile. En Chile, su rango de distribución geográfica abarca desde la cuenca del Río Lluta (∼ 18° S) hasta la cuenca del Río Aconcagua (∼ 33° S) (Velásquez et al 2020) (Figura 1 A). En estas cuencas, el rango de distribución altitudinal de sus poblaciones está determinada por las condiciones biofísicas del ambiente fluvial (régimen hidrológico, diversidad de hábitats bentónicos, presencia de meandros y canales), el grado de intervención antrópica del cauce (alteración de la dinámica hidrológica, presencia de barreras físicas), y la segregación espacial de los estadios ontogénicos (larvas, juveniles y adultos) en las diferentes zonas limnéticas del sistema (hábitat estuarino: desembocadura; hábitat fluvial: potamon y ritron) (Velásquez et al 2022a).…”

“…It is then remarked the need to design and develop, together with stakeholders, further conservation and management actions aiming at supporting local decision-making and granting greater resilience to the species and fishery in a context of great environmental vulnerability, given the current scenario of water scarcity that affects this and other basins in northern Chile. Bahamonde and López 1963;Bahamonde and Vila 1971;Bahamonde et al 1998;Jara et al 2006;Dennenmoser et al 2010;Morales and Meruane 2013a;Velásquez et al 2020). A) Geographic distribution range in northern Chile (gray outline).…”

“…Figure 1. Biogeographic synopsis of Cryphiops caementarius in Continental Chile (sensuBahamonde and López 1963;Bahamonde and Vila 1971;Bahamonde et al 1998;Jara et al 2006;Dennenmoser et al 2010;Morales and Meruane 2013a;Velásquez et al 2020). A) Geographic distribution range in northern Chile (gray outline).…”

Recomendaciones socioecológicas para el manejo del camarón de río Cryphiops caementarius frente a encauzamientos fluviales en el norte semiárido de Chile

“…El camarón de río Cryphiops caementarius (Molina, 1782) es una especie de relevancia ecológica y económica en las cuencas del norte de Chile, y constituye una pesquería artesanal de pequeña escala (Morales y Meruane, 2013), en un territorio que abarca desde la cuenca del río Lluta hasta la cuenca del río Aconcagua (~18º-33ºS) (Velásquez et al, 2020). Actualmente las poblaciones de esta especie se encuentran fuertemente sometidas a diversas presiones ambientales de origen antrópico, como la sobrepesca, fragmentación de hábitat y escasez hídrica, que han puesto en riesgo su conservación, así como la sustentabilidad de su pesquería (Velásquez et al, 2022a,b).…”