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[This corrects the article DOI: 10.1371/journal.pone.0300820.].

Red snapper fishing (Lutjanus purpureus) is an important fishing activity for the Brazilian economy due to its export. The scarcity of up-to-date information on this system's ecology, economy, and social characteristics contributes to inefficient management. We analyze whether the commercial snapper fishery on the Amazon continental shelf is socioecologically sustainable. For this, an assessment tool was used that can be applied to fishing systems with little data, the Fisheries Performance Indicators (FPI). The results showed that the critical points of this activity are mainly related to the Ecological indicator (2.3) and the Economic indicator (2.8). The best indicator was the Community (3.8). The problems that put at risk the permanence of the activity and its maintenance are: (i) fishing for juveniles; (ii) illegal vessels; (iii) lack of collaboration of the fishing sector with science, and (iv) unreliability of data supplied. All the points mentioned make the snapper fishery on the north coast of Brazil socio-ecologically unsustainable in the long term.

Brown shrimp (Penaeus subtilis) trawling in the northern coastal waters of Brazil is an industrial fishing activity with a share in the international market and an important resource in the fishery market. Due to the scarcity of updated information on this practice and owing to its complexity, it is difficult to have a measurement of all dimensions of the development of this fishery, whether they are ecological, economic, or social-institutional. The present paper uses an assessment tool focused on data-poor fishery systems, the Fishery Performance Indicators (FPIs), to assess the multidimensional conditions of this fishery. The indicators were assessed between 2019 and 2020, and the metrics were based on public official data, scientific publications, in loco consultations with production agents, and databases of research projects. Results showed that the critical points of this activity are primarily related to the ecological indicator (1.75), which obtained a lower score compared to other fisheries assessed using the same methodology. This is due to its low selectivity, which results in high by-catch volumes and discards. The limited participation of productive chain actors also restrains the efficacy of management measures, which hampers successful resource management. This issue maximizes other setbacks throughout the productive chain, such as economic and social factors.

Combining scientific information with fishers’ perceptions may be a robust approach for directing decision-makers working with marine ecosystems. This is particularly the case when baseline data on a vulnerable stock are poor, as the integration of fishers’ experiential knowledge can help fill data gaps, as well as inform legitimate management actions, and empower fishing communities in resource management. This study aimed to analyze fishers’ knowledge regarding the biology (reproduction, growth, and maximum size) and temporal changes in the abundance and size of six commercially important marine species (red porgy Pagrus pagrus, veined squid Loligo forbesii, blue jack mackerel Trachurus picturatus, blackspot seabream Pagellus bogaraveo, blackbelly rosefish Helicolenus dactylopterus, and European conger Conger conger) in the Azores small-scale communities. Additionally, a comparison between fishers’ knowledge and available scientific information was performed to determine the former’s value and its possible complementarity with the latter. A total of 105 fishers were surveyed in the nine islands of the archipelago. The results demonstrated a reasonable level of agreement between the information from fishers and scientific literature on the species-specific spawning seasons and growth rates. The median values of size at maturity and maximum length were not statistically different between data sources. Most participants indicated size and abundance trends that were consistent with the literature. This study highlights the usefulness of fishers’ perceptions in improving knowledge about species characteristics and temporal changes in commercially exploited stocks, especially when scientific research is limited, but further research should be encouraged to improve the reliability and consistency of these results.

Deep-sea fisheries are of important economic value. Therefore, it is necessary to generate biologically and ecologically based fishing plans to make this fishery sustainable over time. The silver scabbardfish, Lepidopus caudatus, is a worldwide-distributed demersal fish, commercially exploited in the Azores. Despite L. caudatus high landings and discharges in the region, information about its ecology, population structure, biology and fisheries remains little-known. This work analyzed scientific survey and fishery-dependent data from the past 30 years to understand the changes in abundance, spatial distribution and life history of this species. Lepidopus caudatus spatial distribution was associated with depths between 200 and 400 m, close to seamounts and islands, and on sandy bottoms. The size structure varied yearly, and the population was dominated by females (sex ratio, M:F = 0.46:1). Growth rates were between the estimated values in previous studies in the Azores and indicated a slow-grower species (L∞ = 171.62 cm, k = 0.12 year−1, Φ’ = 3.52). The abundance indices highlighted a declining tendency, and this result was backed by the high exploitation rate for the fish in the region (E = 0.53). Lack of management measurements and the species’ vulnerability could lead to the depletion of this species.

Given the scarcity of information suitable for stock assessments, the growth and mortality of seven exploited marine fishes in Azorean waters were estimated based on length-frequency data. The studied species were Trachurus picturatus, Sparisoma cretense, Scomber colias, Scorpaena scrofa, Serranus atricauda, Seriola spp. and Aphanopus carbo. The growth parameters L∞ (cm), k (year−1) and ϕ’ estimated through the ELEFAN_GA_boot routine were set at 55.87, 0.08 and 2.39 for T. picturatus; 55.03, 0.11 and 2.53 for S. cretense; 55.93, 0.18 and 2.76 for S. colias; 61.11, 0.11 and 2.61 for S. scrofa; 52.10, 0.12 and 2.51 for S. atricauda; 107.33, 0.12 and 3.18 for Seriola spp.; and 133.16, 0.09 and 3.19 for A. carbo; respectively. The total mortality rate estimated using the length–converted catch curve method was 0.22, 0.35, 0.58, 0.32, 0.31, 0.39 and 0.22 year−1; the natural mortality included 0.15, 0.20, 0.30, 0.20, 0.21, 0.21 and 0.16 year−1; and fishing mortality rate 0.07, 0.15, 0.28, 0.12, 0.10, 0.18 and 0.06 year−1, respectively, for the species mentioned. The relatively large sizes and slow growth with a low natural mortality rate indicate a high vulnerability to overfishing. Therefore, assessment and management initiatives are highly encouraged to ensure the sustainability of the resources.

The spiny lobster Palinurus elephas has been intensively harvested across its range and is generally considered overfished, with global landings declining sharply from an average of 820 t in 1960–79 to 385 t in 2000–19. Despite its economic and ecological importance, limited information is available to perform stock assessments and make robust management decisions. In this study, demographics and exploitation levels of P. elephas were determined from coastal areas of the Azores, and the relevance of these data for conservation planning was discussed. Carapace length varied between 39.6 and 174.3 mm, with mean sizes decreasing by depth. Males reached larger sizes and grew faster than females but were less dominant. Lifespan was 43 years for females and 60 years for males. The estimated mean length at first capture was 101.65 mm—around 58% of its asymptotic length. Fishing mortality and exploitation levels were close to the optimal values, indicating an uncertain future for Azorean populations if stock assessment and management initiatives are not focused on this species. Conservation and management strategies may benefit from these results under the ‘precautionary approach’ principle. However, up–to–date and accurate catch and fishing effort data need to be urgently collected.

The aim of this study was to analyze the effects of climate and marine variability on the catches of Lutjanus purpureus in three sectors of the Amazon Continental Shelf. Remote sensing data were compared with landings (CPUE) between 1997 and 2007 and analyzed for partial influence obtained through the Generalized Additive Model. Additionally, significant variables were analyzed through Wavelet Cross‐Spectrum, and periods of high correlation between variables in space and time were identified. The results indicated a high coherence between catch per unit effort (CPUE) and environmental variables on an interannual scale, suggesting that Red Snapper fishing is mainly influenced by the seasonal effects of oceanographic variables. These results suggest that fluctuations in Red Snapper catches between 1997 and 2007 may be the result of natural processes that occur in the Amazon Continental Shelf every year in synergy with environmental variables, which are also indirectly affected by the El Niño–Southern Oscillation (ENSO) pattern. [ABSTRACT FROM AUTHOR]