First Assessment of the Impacts of the COVID-19 Pandemic on Global Marine Recreational Fisheries

This work is the result of an international research effort to determine the main impacts of the COVID-19 pandemic on marine recreational fishing. Changes were assessed on (1) access to fishing, derived from lockdowns and other mobility restrictions; (2) ecosystems, because of alterations in fishing intensity and human presence; (3) the blue economy, derived from alterations in the investments and expenses of the fishers; and (4) society, in relation to variations in fishers’ health and well-being. For this, a consultation with experts from 16 countries was carried out, as well as an international online survey aimed at recreational fishers, that included specific questions designed to capture fishers’ heterogeneity in relation to behavior, skills and know-how, and vital involvement. Fishers’ participation in the online survey (5,998 recreational fishers in 15 countries) was promoted through a marketing campaign. The sensitivity of the fishers’ clustering procedure, based on the captured heterogeneity, was evaluated by SIMPER analysis and by generalized linear models. Results from the expert consultation highlighted a worldwide reduction in marine recreational fishing activity. Lower human-driven pressures are expected to generate some benefits for marine ecosystems. However, experts also identified high negative impacts on the blue economy, as well as on fisher health and well-being because of the loss of recreational fishing opportunities. Most (98%) of the fishers who participated in the online survey were identified as advanced, showing a much higher degree of commitment to recreational fishing than basic fishers (2%). Advanced fishers were, in general, more pessimistic about the impacts of COVID-19, reporting higher reductions in physical activity and fish consumption, as well as poorer quality of night rest, foul mood, and raised more concerns about their health status. Controlled and safe access to marine recreational fisheries during pandemics would provide benefits to the health and well-being of people and reduce negative socioeconomic impacts, especially for vulnerable social groups.Versión del edito

Extreme roll angles in Argentine sea bass: Could refuge ease posture and buoyancy control of marine coastal fishes?

The swim bladder provides a mechanism for buoyancy regulation in teleosts. However, in certain species, its location can result in an unstable body position, with associated energetic costs assumed for maintaining posture in addition to the energetic demands from swim bladder volume regulation. Direct observations show that some body-compressed, cave-refuging teleosts that nominally operate near neutral buoyancy may adopt unusual body attitudes within crevices. We hypothesize that these fishes may relax their buoyancy and posture control mechanisms during periods of rest. A prediction derived from this is that resting fish may adopt a wide range of roll angles (i.e., rotation about their longitudinal axis) inside caves. To quantify this behavior and for testing this hypothesis, triaxial accelerometers were deployed on free-living, cave-refuging Argentine sea bass Acanthistius patachonicus, and the relationship between roll angle and a proxy for activity (defined as the vectorial dynamic body acceleration, VeDBA) was analyzed. The results were compared with data available for three other species of fishes with disparate body forms and lifestyles: the pelagic whale shark Rhincodon typus, the dorsoventrally compressed benthic great sculpin Myoxocephalus polyacanthocephalus, and the fusiform and demersal Atlantic cod Gadus morhua. Inactive Argentine sea bass adopted a wide variety of roll angles, including extreme ones exceeding 80°, but had lower roll angles closer to an upright posture primarily associated with higher activity levels. In contrast, the great sculpin and Atlantic cod both rested at a close to upright roll angle but had higher activity levels associated with larger roll angles. Whale shark did not rest for the duration of the recorded period and also showed higher activity levels associated with larger roll angles. We propose that relaxation of buoyancy and posture control may help to reduce the metabolic rate in laterally compressed, cave-refuging fishes during periods of rest within crevices.Fil: Ciancio Blanc, Javier Ernesto. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - Centro Nacional Patagónico. Instituto de Biología de Organismos Marinos; ArgentinaFil: Venerus, Leonardo Ariel. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - Centro Nacional Patagónico. Centro para el Estudio de Sistemas Marinos; ArgentinaFil: Trobbiani, Gastón Andres. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - Centro Nacional Patagónico. Centro para el Estudio de Sistemas Marinos; ArgentinaFil: Beltramino, Lucas Esteban. Universidad Nacional de la Patagonia; Argentina. Consejo Nacional de Investigaciones Científicas y Técnicas; ArgentinaFil: Gleiss, Adrian C.. Murdoch University; AustraliaFil: Wright, Serena. Centre For Environment, Fisheries And Aquaculture Scien; Reino UnidoFil: Norman, Brad. Ecocean Inc; AustriaFil: Holton, Mark. Swansea University; Reino UnidoFil: Wilson, Rory P.. Swansea University; Reino Unid

Genetic structure and different color morphotypes suggest the occurrence and bathymetric segregation of two incipient species of Sebastes off Argentina

Rockfishes of the genus Sebastes are extensively distributed in the Pacific and Atlantic oceans. Although the occurrence of two morphologically similar species in the Southern Hemisphere, Sebastes oculatus and Sebastes capensis, is now clearly established, the taxonomic status and phylogeographic patterns for the genus in the region have not yet been completely resolved. In this study, we provide new insights into the taxonomy and evolutionary relationships of rockfishes inhabiting the Southwestern Atlantic Ocean, off the coast of mainland Argentina, by combining mitochondrial DNA (mtDNA) control region sequences, microsatellite data and color pattern analyses. Differences in coloration (-dark- and -light- fish) together with bathymetric segregation between color morphotypes were evident from fish collection and literature review. In addition, the mtDNA phylogenetic analysis and Bayesian clustering analysis using microsatellite data separated the fish into two distinct groups (FST = 0.041), most likely representing incipient species. Our results suggest that speciation-by-depth in the absence of physical barriers could be a widespread mechanism of speciation in Sebastes from both the Northern and Southern Hemispheres. Nevertheless, the degree of genetic differentiation found, added to the large number of individuals displaying high levels of admixture, points to the occurrence of incomplete reproductive barriers between color morphotypes. Beyond the taxonomic and phylogeographic implications of our findings, the occurrence of distinct groups of Sebastes off the coast of Argentina being targeted by different fisheries (angling and trawling) have consequences for the design and implementation of appropriate fishery regulations to avoid overharvest of either group.Fil: Venerus, Leonardo Ariel. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Nacional Patagónico; ArgentinaFil: Ciancio Blanc, Javier Ernesto. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Nacional Patagónico; ArgentinaFil: Riva Rossi, Carla Marcela. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Nacional Patagónico; ArgentinaFil: Gilbert Horvath, Elizabeth A.. National Marine Fisheries Service; Estados UnidosFil: Gosztonyi, Atila Esteban. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Nacional Patagónico; ArgentinaFil: Garza, John Carlos. National Marine Fisheries Service; Estados Unido