Artisanal fisheries are essential, but for most the status of the stock supporting the fishing ac... more Artisanal fisheries are essential, but for most the status of the stock supporting the fishing activity remains unknown due to lack of data and difficult access to sampling. For example, the artisanal fishery of sea silverside Odontesthes (Austromenidia) regia, in the Los Lagos administrative region of Chile, requires a data-limited approach to determine its status because the fishery administration has not invested in its monitoring. The approach consisted of estimating the spawning potential ratio (SPR) from length-frequency data collected in 2019 using length-based spawning potential ratio (LBSPR) and biological reference points using the only-catch optimized method (OCOM) to catch data covering from 1960 to 2020. In addition, five age-structured sea silverside populations were simulated considering uncertainty in recruitment and utilizing life-history parameters estimated by FishLife. According to LBSPR, the SPR was 0.58 (95% confidence intervals: 0.5-0.7), suggesting a fully ex...
The abundance of juvenile fish changes due to endogenous processes, and determining the functiona... more The abundance of juvenile fish changes due to endogenous processes, and determining the functional relationships among conspecifics is essential for fisheries’ management. The hake (Merluccius gayi) is an overexploited demersal fish widely distributed in Chile, from 23°39′ S to 47°00′ S in shallow and deep water over the continental shelf and shelf break. We studied the spatiotemporal distribution of hake juveniles (from ages 0 and 1), emphasizing endogenous relationships among juveniles and adults. The abundance per age data were obtained from bottom trawl cruises carried out in the austral winter between 1997 and 2018. Generalized additive models showed a similar spatiotemporal pattern for ages between 0 and 1, and negative effects of adult hake aged seven and older on the abundance of the young generation. Regarding the changes in juvenile abundance, the residual deviance of selected models explained 75.9% (for the age 0) and 95.3% (for the age 1) of the null deviance, revealing ...
River runoff to the coastal zone is one of the most important environmental variables that influe... more River runoff to the coastal zone is one of the most important environmental variables that influences the structure and functioning of the neritic trophic web and modulates temporal fluctuations of coastal fishery production in many ecosystems worldwide. The relationship between recruitment of anchovy (Engraulis ringens) and common sardine (Strangomera bentincki) in central-south Chile (34°–40°S) and fluctuations in river runoff was analyzed during the last two decades (1999–2018) using linear and nonlinear regression models. River runoff was also incorporated as a co-variate in Beverton-Holt (BH) stock-recruitment models. Anchovy recruitment was found to be positive and significantly associated with river runoff for all analyzed rivers both for the runoff calculated during its main reproductive period (July–October) and for each single month during this period. This detected nonlinear relationship remained significant when runoff was analyzed for the central macrozone (CMZ) and sou...
Artisanal fisheries are essential, but for most the status of the stock supporting the fishing ac... more Artisanal fisheries are essential, but for most the status of the stock supporting the fishing activity remains unknown due to lack of data and difficult access to sampling. For example, the artisanal fishery of sea silverside Odontesthes (Austromenidia) regia, in the Los Lagos administrative region of Chile, requires a data-limited approach to determine its status because the fishery administration has not invested in its monitoring. The approach consisted of estimating the spawning potential ratio (SPR) from length-frequency data collected in 2019 using length-based spawning potential ratio (LBSPR) and biological reference points using the only-catch optimized method (OCOM) to catch data covering from 1960 to 2020. In addition, five age-structured sea silverside populations were simulated considering uncertainty in recruitment and utilizing life-history parameters estimated by FishLife. According to LBSPR, the SPR was 0.58 (95% confidence intervals: 0.5-0.7), suggesting a fully ex...
The abundance of juvenile fish changes due to endogenous processes, and determining the functiona... more The abundance of juvenile fish changes due to endogenous processes, and determining the functional relationships among conspecifics is essential for fisheries’ management. The hake (Merluccius gayi) is an overexploited demersal fish widely distributed in Chile, from 23°39′ S to 47°00′ S in shallow and deep water over the continental shelf and shelf break. We studied the spatiotemporal distribution of hake juveniles (from ages 0 and 1), emphasizing endogenous relationships among juveniles and adults. The abundance per age data were obtained from bottom trawl cruises carried out in the austral winter between 1997 and 2018. Generalized additive models showed a similar spatiotemporal pattern for ages between 0 and 1, and negative effects of adult hake aged seven and older on the abundance of the young generation. Regarding the changes in juvenile abundance, the residual deviance of selected models explained 75.9% (for the age 0) and 95.3% (for the age 1) of the null deviance, revealing ...
River runoff to the coastal zone is one of the most important environmental variables that influe... more River runoff to the coastal zone is one of the most important environmental variables that influences the structure and functioning of the neritic trophic web and modulates temporal fluctuations of coastal fishery production in many ecosystems worldwide. The relationship between recruitment of anchovy (Engraulis ringens) and common sardine (Strangomera bentincki) in central-south Chile (34°–40°S) and fluctuations in river runoff was analyzed during the last two decades (1999–2018) using linear and nonlinear regression models. River runoff was also incorporated as a co-variate in Beverton-Holt (BH) stock-recruitment models. Anchovy recruitment was found to be positive and significantly associated with river runoff for all analyzed rivers both for the runoff calculated during its main reproductive period (July–October) and for each single month during this period. This detected nonlinear relationship remained significant when runoff was analyzed for the central macrozone (CMZ) and sou...
Uploads
Papers by Luis Cubillos