Bases conceptuales para la aplicacion de una evaluacion de estrategias de manejo (EEM) en sardina comun (Strangomera bentincki) y anchoveta (Engraulis ringens) en la zona centro sur de Chile

Abstract

Bases conceptuales para la aplicación de una evaluación de estrategias de manejo (EEM) en sardina común (Strangomera bentincki) y anchoveta (Engraulis ringens)en la zona centro-sur de Chile RESUMEN. Se identifican los factores claves a considerar en el desarrollo de una evaluación de estrategias de manejo (EEM) para los recursos pequeños pelágicos en la zona de centro-sur de Chile, sardina común (Strangomera bentincki) y anchoveta (Engraulis ringens). En Chile, la EEM no ha sido aplicada al manejo de estas pesquerías y la asesoría científica se ha desarrollado sobre la evaluación de estrategias de explotación utilizando modelos de evaluación mono-específicos. Para ambas especies se analizan los siguientes tópicos: i) alternancia en la abundancia poblacional asociada a los pulsos de reclutamientos y capturas, ii) variabilidad temporal en la fuerza del reclutamiento, iii) estacionalidad del crecimiento cohorte y especie-específico, y iv) relación ambiente-recurso. Los resultados evidencian que los tópicos analizados debieran ser considerados en la construcción de un modelo operativo y/o en la regla de cosecha, dado el carácter mixto de ambas pesquerías, su marcada alternancia y la influencia de las condiciones ambientales. Por lo tanto, se propone que el diseño e implementación de una EEM para sardina común y anchoveta, incluya los elementos señalados en un marco de evaluación multi-especifico y de manejo de carácter mixto. Palabras clave: anchoveta; sardina común, modelo operativo, estrategias de manejo, ambiente-recurso, Pacífico suroriental. Conceptual bases for implementing a management strategy evaluation (MSE) for common sardine (Strangomera bentincki) and anchovy (Engraulis ringens) in south-central zone of ChileABSTRACT. Key factors to consider in the development of a management strategy evaluation (MSE) for small pelagic fish resources of south-central Chile, common sardine (Strangomera bentincki) and anchovy (Engraulis ringens) were identified. In Chile, MSE has not been applied to manage these fisheries and scientific advice has been developed on the evaluation of harvest strategies using single species stock assessment models. For both resources the following topics were analyzed: i) alternation of population abundance pulses associated with recruitment and catches, ii) temporal variability in recruitment strength, iii) seasonality of cohort and speciesspecific growth, and iv) relationship resource-environment. Results show that the topics analyzed in this work should be considered in the development of an operating model and/or harvest control rules, given the mixed nature of both fisheries, the marked alternation and the influence of environmental conditions. Therefore, it is proposed that the design and implementation of a MSE for sardine and anchovy complex, considers the elements outlined in this study and within the framework of multi-specific assessment and mixed fishery management.

Effect of wind variability on the recruitment of anchovy Engraulis ringens in the southern Humboldt upwelling ecosystem

“…Exogenous factors have been widely shown to have a direct and critical effect on the population dynamics of pelagic fish (Burbank et al, 2023; Lowerre‐Barbieri et al, 2017; Ospina‐Alvarez et al, 2022). For the anchovy from south‐central Chile, warm sea surface temperature (SST) conditions related to El Niño events were positively correlated with high recruitment (Cubillos & Arcos, 2002), while chlorophyll‐a was not significant in explaining recruitment (Arteaga et al, 2014; Gomez et al, 2012). Alternatively, Zunguza et al (2022) showed the relevance of river runoff as an important factor in explaining anchovy recruitment, suggesting that anomalies of freshwater input during the main reproductive period of anchovy affected both the survival of early life stages and recruitment.…”

“…Therefore, this model was not selected as a predictive model to explain recruitment. Chlorophyll‐a has been established to explain the recruitment variability of pelagic fish in south‐central Chile (Arteaga et al, 2014; Gomez et al, 2012). In our study, the model that included chlorophyll‐a, wind, and spawning biomass showed a slight positive relationship and high deviance explained.…”

“…Spawning is maximized between August and October and may extend into summer (Claramunt et al, 2014). Recruitment in this species occurs from October to March (Cubillos & Arcos, 2002) and is highly variable because of the environmental conditions of the Humboldt system (Arcos et al, 1996; Arcos et al, 2004; Arteaga et al, 2014; Cubillos & Arcos, 2002; Gomez et al, 2012; Parada et al, 2013; Yáñez et al, 1992; Zunguza et al, 2022). Additionally, this species sustains an important fishery through both artisanal and industrial fleets, averaging annual landing volumes around 250 thousand tons (Zúñiga, 2021).…”