Fisheries Management and Ecology最新文献

Mylossoma albiscopum is one of the primary species consumed by humans in the Colombian Amazon, but understanding is limited on its life history traits and the current status. Therefore, the fishery was monitored in the Putumayo River basin between 2016 and 2023 to estimate growth parameters and assess stock status using the data-limited LB-SPR method. Asymptotic length (L_∞) was 28.63 cm, natural mortality (M) was 0.92, von Bertalanffy growth (k) was 0.39, and length at 50% maturity (L_m50) was 15.0 cm. The spawning potential ratio (0.39) was similar to the reference point (0.40), so the fishery exploited the population near its optimal level. We recommend that the Colombian fisheries authority consider L_m50 as the legal catch length limit and continue annual evaluations of the fishery to ensure its sustainability.

Dam development is fragmenting migratory pathways in the Mekong Basin, yet scientific understanding of Mekong fish migrations is limited. Therefore, the first-ever transboundary acoustic telemetry network was deployed in the Mekong, Sekong, and Sesan rivers in Cambodia and Lao PDR to track movements of 81 individual fish representing 12 different species from June 2022 through March 2024. Upstream movement by Pangasius conchophilus during the transition between dry and wet seasons aligned with local ecological knowledge. Movements of Pangasius larnaudii between the Mekong and Sekong rivers represent a previously undocumented migratory pathway for this species. Long-distance movements by Hemibagrus wyckioides into the 3S basin contradicted the assumption that the species moves only short distances. Together, these findings imply that fragmentation of riverine habitats from planned dams may lead to greater impacts on populations of these species than were formerly assumed.

This study documented the first evidence of healing and long-term survival of blackmouth catsharks (Galeus melastomus) following traumatic mandibular fractures and associated soft tissue avulsions that resulted from previous captures on deep-sea longlines. All sharks were actively feeding, despite acute and healed lesions, which suggests that such severe trauma did not impair feeding. Additionally, one female with a healed lesion and three developed eggcases indicated that reproduction was unaffected. Magnetic resonance imaging (MRI) showed no other alterations in the chondrocranium, splanchnocranium, or broader skeletomuscular system and major viscera. Although the small sample size does not fully represent postrelease survival for the species after capture in longline fisheries, the resilience observed was significant for conservation and fisheries management, which underscores the need for further research.

The classical surplus production model is less explanatory when biomass is low and the catch is high, and also does not explicitly include a stock recruitment process. Nevertheless, a classical Schaefer surplus production function (SF) has been predominantly used for current anchovy (Engraulis japonicus) stock assessments in the Bohai and Yellow Seas in China. The Beverton–Holt-driven production function (BHDPF) model may mitigate drawbacks of the classical SF model. To assess status of the anchovy stock in the Bohai and Yellow Seas, the SF, BHDPF, and Stock Synthesis 3 (SS3) (an integrated analysis model) were used. The SF suggested a recovered stock, with stable catch, whereas the BHDPF and SS3 models suggested that the stock biomass was the lowest during the study period, thereby necessitating a reduction in catch. BHDPF and SS3 were consistent with one another the SF. Under the BHDPF assumption, increasing and decreasing biomass trends may result in countertrend catches, and high catches at low biomass. The BHDPF may serve as an assessment alternative for fisheries lacking age-structure data. Abundance index data plays a significant role in the current assessment of the Bohai and Yellow Seas anchovy stock, and more research is needed to improve its accuracy.

Fisheries are essential for nutritional and economic stability in many countries, particularly small island developing states. In The Bahamas, ~25% of households depend on fisheries-related income, and Bahamians rely on seafood for ~15% of their animal protein. However, our understanding of fisheries is largely based on national statistics that may not reflect the diversity of fishers, particularly in less developed Family Islands. We interviewed 375 Bahamian fishers from five major islands, Abaco, Andros, Eleuthera, Long Island, and New Providence, that varied in socioeconomics, human population density, natural resource diversity, and cultural practices. Bahamian fishers were largely driven by economics, with ~70% identifying as commercial fishers and > 80% of income derived from fishing activities for all fishers. Fishers in more developed islands used more modern methods (e.g., diving, pots & traps) to catch economically valuable species (e.g., Panulirus argus) at greater distances from home islands, aided by larger fishing vessels. In contrast, fishers from Family Islands used more traditional methods (e.g., handlines) to catch Lutjanidae and other species in nearshore waters closer to home islands. Variability among islands appears to be attributed to differences in access to resources, infrastructure, financial motivation, and cultural practices. Similar to other small developing island nations, diversity in fisher behavior among and within Bahamian islands necessitates more attention and resources to develop, implement, and enforce fisheries regulations to ensure sustainability, which is essential as global demand for seafood continues to grow amidst widespread overfishing.

The growing popularity of digital catch logs may present a low-cost opportunity to monitor climate change effects on the distribution and relative abundance of game fishes over large spatial scales. We analyzed data from a popular fishing app to identify spatiotemporal trends in freshwater game fish catches throughout the contiguous the United States during 2015–2021. Warm-water species became more common than cool-water species in many locations. Increases in relative abundance tended to occur in northern range boundaries or non-native ranges, and declines tended to occur at southern range boundaries. Although catch log data can be biased and results may reflect alternative phenomena operating or interacting at similarly large spatial scales (e.g., cultural eutrophication, changes in game fish popularity), climate change remains a viable explanation. Future research should further explore app data as a potential tool for monitoring game fish responses to climate change and other stressors over longer time frames and at multiple spatial scales.