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Size‐ and species‐selective harvest inevitably alters the composition of targeted populations and communities. This can potentially harm fish stocks, ecosystem functionality, and related services, as evidenced in numerous commercial fisheries. The high popularity of rod‐and‐reel recreational fishing, practiced by hundreds of millions globally, raises concerns about similar deteriorating effects. Despite its prevalence, the species and size selectivity of recreational fisheries remain largely unquantified due to a lack of combined catch data and fisheries‐independent surveys. This study addresses this gap by using standardised monitoring data and over 60,000 digital angling catch reports from 62 distinct fisheries. The findings demonstrate a pronounced selectivity in recreational fisheries, targeting top predators and large individuals. Catch‐and‐release practices reduced the overall harvest by 60% but did not substantially alter this selectivity. The strong species‐ and size‐specific selectivity mirror patterns observed in other fisheries, emphasising the importance of managing the potential adverse effects of recreational fisheries selective mortality and overfishing. [ABSTRACT FROM AUTHOR]

Effective fisheries management requires accurate estimates of stock biomass and trends; yet, assumptions in stock assessment models generate high levels of uncertainty and error. For 230 fisheries worldwide, we contrasted stock biomass estimates at the time of assessment with updated hindcast estimates modeled for the same year in later assessments to evaluate systematic over- or underestimation. For stocks that were overfished, low value, or located in regions with rising temperatures, historical biomass estimates were generally overstated compared with updated assessments. Moreover, rising trends reported for overfished stocks were often inaccurate. With consideration of bias identified retrospectively, 85% more stocks than currently recognized have likely collapsed below 10% of maximum historical biomass. The high uncertainty and bias in modeled stock estimates warrants much greater precaution by managers. [ABSTRACT FROM AUTHOR]

Despite concerns about overfishing and the potential impact of release programs on wild populations, our study of 3116 individuals from 13 wild populations and 2787 individuals from two cultured populations in Zhejiang and Fujian provinces spanning 2008 to 2023 reveals a relatively stable genetic diversity in Larimichthys crocea. Surprisingly, the genetic diversity of wild large yellow croaker populations has remained consistent over the years, suggesting minimal influence from population declines due to overfishing. With the exception of populations in Sansha Bay and Luoyuan Bay, no significant genetic differences were observed among wild populations, indicating a single panmictic genetic population across the East and South China seas. Notably, significant genetic differentiation exists between cultured and wild populations, suggesting a possible limited genetic adaptation of cultured‐released individuals to the wild environment. The genetic differences observed between the Sansha Bay, with its adjacent Luoyuan Bay populations, and other wild populations underscore the dual effects of habitat environment and farming activities on the genetic structure of large yellow croaker. Our findings suggest that, despite declines in population numbers due to overfishing and expands extensive cultured releases, the genetic diversity of L. crocea populations remains largely unaffected. Moreover, the L. crocea population along the Chinese coast appears to form a single panmictic population with considerable genetic diversity. [ABSTRACT FROM AUTHOR]

The Atlantic pearl oyster Pinctada radiata (Leach, 1814), the first documented Lessepsian bivalve species to enter the Mediterranean basin, is present in various coastal areas in Greece, and constitutes, almost exclusively, a domestic commercial bivalve resource. The present study aimed to contribute to the limited information available on P. radiata population structure and dynamics in Hellenic waters, especially following the recent enforcement of legislation for regulation of its fishery. A total of 703 individuals were collected using scuba diving from the South Evoikos Gulf. The male-to-female ratio (1:1.70) significantly departed from 1:1. A higher probability for female prevalence was exhibited for shell heights over 50.77 mm. Significant differences were exhibited in the shell height–total weight relationship between the sexes. The fourth-year class was the dominant cohort, comprising 50.09% of the population, out of the seven age classes identified. Asymptotic length was estimated at 109.1 mm and growth index at 3.35, respectively. Longevity was estimated at 15.7 years, with natural mortality (M) at 0.39 and total mortality (Z) at 0.76. The probability of capture (LC50) was estimated at 50.72 mm at 2.8 years. Biological reference points FMSY and EMSY were higher than the fishing mortality and current exploitation rate, respectively, indicating the potential for further population exploitation. [ABSTRACT FROM AUTHOR]

Coregonus ussuriensis Berg, distributed widely in cold waters above 45° N latitude, is a savored freshwater whitefish that has been included in the list of endangered animals as a consequence of overfishing. Lack of genomic information seriously hampers evolutionary and genetic research on C. ussuriensis warranting the need to assemble a high-quality reference genome to promote its genetic breeding. We assembled and constructed a reference chromosome-level C. ussuriensis genome (sequence length, 2.51 Gb; contig N50 length, 4.27 Mb) using PacBio sequencing and Hi-C assembly technology, 3,109 contigs were assembled into scaffolds, resulting in a genome assembly with 40 chromosomes and a scaffold N50 length of 62.20 Mb. In addition, 43,320 protein-coding genes were annotated. The peak Ks position in the species comparison reflects the whole-genome replication event of C. ussuriensis. This chromosome-level genome provides reference data for further studies on the molecular breeding of C. ussuriensis. [ABSTRACT FROM AUTHOR]

Marine finfish landings in Cuba have decreased during the last 30 years. However, in Cuba's most productive fishing region, certain species, including rays, herrings, and snappers, have had increased landings over the past decade. Despite these anomalies, no comprehensive analysis of the interactions among multispecies landing dynamics, environmental factors, and fishing efforts has been carried out. This study estimates the dynamics of multispecies finfish landings between 1981 and 2017 on the southeastern coast of Cuba. A log-normal generalized additive model (GAM) was fit to evaluate the effects of various environmental and effort-related variables on the total landings. During the period analyzed, the finfish landings and fishing effort decreased by 46% and over 80%, respectively. Despite concerns about overfishing, landings per unit of effort (LPUE) increased by 2.8 times. The total fish landings were significantly related to changes in the fishing effort, coastal vegetation, rainfall, chlorophyll-a, and the Southern Oscillation Index (SOI). This study highlights the changing relationship between the landings and fishing effort, suggesting that LPUE may not accurately reflect true stock abundance. The findings of this study will assist in integrating the dynamics of finfish species, ecosystem status, and management actions for Cuba's most productive fishing zone. [ABSTRACT FROM AUTHOR]

Daya Bay is a semi-enclosed bay in the South China Sea which is a coastal ecosystem with significant ecological and economic value that is subjected to a variety of anthropogenic disturbances. However, long-term variation in fish community structure in this Bay remains uncertain. In this study, we aimed to explore the changing characteristics of fish species composition and community structure in Daya Bay during the past 30 years using data from 1989 to 2021 from bottom trawl surveys and historical literature data. As of now, a total of 544 species of fish have been identified in the Bay, belonging to 24 orders and 125 families. The structure of the fish community in the bay has changed over time. Firstly, there has been a clear decrease in the number of species and biomass of large fish. Secondly, the number of fish constituent orders and families has decreased. Moreover, both the average taxonomic distinctness and variation in taxonomic distinctness decreased from 1989 to 2021. Thirdly, there is low similarity among fishes at different time phases and distinct changes in the composition of dominant species. Present results indicate that the fish community structure in Daya Bay has tended to reflect a decline in diversity, shifts in composition, and shrinking of fish body size in the past 30 years. This study improves our understanding of fish species composition and its drivers over time in Daya Bay, providing important knowledge to support the protection and restoration of this ecosystem and the important ecosystem services it provides. [ABSTRACT FROM AUTHOR]

A list of coral reef fish species of Huaguang Reef was compiled in 2023 using hand fishing, diving fishing, underwater video, and eDNA detection, combined with historical data from 1979 and archival records from the South China Sea Fisheries Research Institute of the Chinese Academy of Fisheries Sciences for the years of 1998, 1999, 2003, and 2005. Successional characteristics of coral reef fishes through time were also explored. The findings revealed: (1) A total of 299 coral reef fish species were identified in Huaguang Reef, categorized into 2 classes, 16 orders, and 56 families, with Perciformes exhibiting the highest species count (234), constituting 78.26% of all species. (2) In comparison to the period of 1979-2005, there was a reduction in the number of species at the order and family levels in 2023 at Huaguang Reef. Both the average taxonomic distinctness (Δ+) and the variation in taxonomic distinctness (Δ+) exhibited a declining trend, indicating disturbances in the fish ecosystem. (3) The proportion of herbivorous fish at Huaguang Reef remained relatively stable in 2023 compared to the 1979-2005 period. Notably, the similarity coefficient of herbivorous fish was the highest among different feeding types, signifying a degraded state of the Huaguang Reef habitat. (4) In contrast to the 1979-2005 period, a significant decline was observed in large-sized and carnivorous fish species at Huaguang Reef in 2023. The low similarity coefficients for both categories, with undiscovered fish species accounting for 58.49% and 45.76% of their respective taxa in the total list, respectively, suggested a notable impact of overfishing on coral reef fishes. The succession patterns revealed in this study provide a theoretical foundation for advancing the sustainable development of coral reef fish resources in the Xisha Islands and offer valuable insights for the protection and management of coral reef fishes. [ABSTRACT FROM AUTHOR]

Obtaining reliable estimates of the effective number of breeders (Nb) and generational effective population size (Ne) for fishery‐important species is challenging because they are often iteroparous and highly abundant, which can lead to bias and imprecision. However, recent advances in understanding of these parameters, as well as the development of bias correction methods, have improved the capacity to generate reliable estimates. We utilized samples of both single‐cohort young of the year and mixed‐age adults from two geographically and genetically isolated stocks of the Australasian snapper (Chrysophrys auratus) to investigate the feasibility of generating reliable Nb and Ne estimates for a fishery species. Snapper is an abundant, iteroparous broadcast spawning teleost that is heavily exploited by recreational and commercial fisheries. Employing neutral genome‐wide SNPs and the linkage‐disequilibrium method, we determined that the most reliable Nb and Ne estimates could be derived by genotyping at least 200 individuals from a single cohort. Although our estimates made from the mixed‐age adult samples were generally lower and less precise than those based on a single cohort, they still proved useful for understanding relative differences in genetic effective size between stocks. The correction formulas applied to adjust for biases due to physical linkage of loci and age structure resulted in substantial upward modifications of our estimates, demonstrating the importance of applying these bias corrections. Our findings provide important guidelines for estimating Nb and Ne for iteroparous species with large populations. This work also highlights the utility of samples originally collected for stock structure and stock assessment work for investigating genetic effective size in fishery‐important species. [ABSTRACT FROM AUTHOR]

Freshwater fish in East African Lakes are under severe threat due to the recently discovered oil and gas in the Albertine Region and overfishing across the entire East African Region. The threats, primarily caused by overfishing, are a matter of declining fish populations and a potential reduction in genetic diversity in the surviving populations due to genetic drift. This study, therefore, is of utmost importance as it assessed genetic diversity in seven populations, including five from native and two from introduced populations. The assessment of genetic diversity in Oreochromis niloticus was conducted using molecular markers in 128 samples. The results showed a moderate genetic variation between native and introduced populations at mitochondrial and microsatellite loci. The potential effects of overfishing, fish introductions, and new threats from cage farming on the genetic diversity and ecological integrity of wildlife species are discussed, highlighting the need for immediate action. [ABSTRACT FROM AUTHOR]

The high economic value and demand for shark fin have significantly increased the vulnerability of the shortfin mako shark (Isurus oxyrinchus Rafinesque, 1810) population in the Indian Ocean, particularly in the southern region of Java and West Nusa Tenggara. This study utilized a length-based assessment method to evaluate the stock status of I. oxyrinchus. Over a span of eight years (2013–2021), data on length frequency and sex composition were collected. The length-based spawning potential ratio (SPR) was employed to investigate the stock status of the fishery. The findings revealed that I. oxyrinchus exhibited a large body size, with an asymptotic length estimated at 386.86 cm total length and a growth coefficient of 0.04/year . Females were more frequently captured than males, and evidence indicated a declining trend in the size of female sharks. A low SPR value of approximately 6% indicated the overfishing condition of mako shark. To ensure the sustainability of the shortfin mako shark population in the Indian Ocean, it is essential to develop effective management strategies through integrated cooperation among the government, fishers, traders, shark industries, and local communities.

This study looked at some biometric and reproductive aspects of the Common carp (Cyprinus carpio) – the overexploited fish species in the Geray Reservoir as a foundation to develop an efficient fisheries management strategy. 50 fish samples (20 to 44 cm and 130 to 2,400 g) were collected between October and May 2022 using a cast net with a mesh size of 6 cm. The ratio of male to female C. carpio (1:0.52) was deviating from the anticipated 1:1 ratio. The absolute fecundity of C. carpio was relatively low (12,375 to 31,392 eggs). Gonadosomatic index varied from 0.01 to 4.6 (male) to 0.24–12.75 (female), and the spawning period of C. carpio extended from December to January. The length-weight relationships for males (TW = 0.0009TL3.87) and females (TW = 0.0007L3.97) indicate that C. carpio had positive allometric growth; which may have been caused by unsuitable habitat conditions and overfishing. There is a need to develop fisheries management like implementing integrated conservation efforts and reducing wetland farming. For this, this information provides a baseline data.

Abstract The effects of discontinuing harmful fishery subsidies in Spain were analysed using a social accounting matrix. The study found that the removal of these subsidies would have negative consequences for the economy. Specifically, there would be a significant decline in the production value of marine resource industries, and industries dependent on fish and shellfish as inputs would experience increased production costs. The exports, mainly to EU countries, would also be impacted, and certain marine resource sectors would experience significant job losses. Fishing families would suffer the greatest reduction in income once subsidies are removed. However, there is potential to mitigate most of the negative impacts by redirecting the removed subsidies, as it is shown for the case of their redirection to research and development industries. The findings of this study provide valuable insights for EU policymakers in implementing specific policies to address the potential consequences on affected sectors, families, and employers as part of the next European strategy, Horizon 2021–2027.

Widas Reservoir is situated in an area of 570 ha in the Pajaran Village, Madiun Regency, East Java Province, Indonesia, playing an essential role in fisheries, with the average fish catch per year of about 283 tons/year. This study explores the standing stock, growth parameters, mortality, and exploitation rates of several dominant fishes in Widas Reservoir. This study was carried out from February to November 2019. Fish stocks were estimated using acoustic tools, fish catch records, and sizes collected by local enumerators. Fish length frequency sampling was conducted on several dominant fish species, such as Oreochromis niloticus, Barbonymus gonionotus, and Osteochilus vittatus. Based on the length-frequency data, estimating fish population dynamics, the fish population dynamics (infinitive length (L∞) and growth coefficient (K)) estimation was run in a time series using the Fish Sock Analysis Tool, II (FISAT II) program package. Moreover, the estimation of natural mortality parameters, the fishing mortality parameter, and the exploitation rate was also performed. The approximated overall fish stock in the Widas Reservoir was about 79,848 kg, which lowered with the increase in water depth. Of particular concern, in the surface layer at a depth between 1–5 m, the fish stock reached 58,813 kg, while in the deeper zone (> 15 m), the value significantly lowered by about 98%, reaching 1,219 kg. These results indicate an overfishing in the Widas Reservoir. The value of the exploitation rate (E) of B. gonionotus was 0.748, O. niloticus 0.8, and O. vittatus 0.7, respectively, proving the overfishing states occurred in the study area. Therefore, regulations governing the number of catches and the use of fishing gear are crucial in Widas Reservoir, particularly the use of lift and gill nets with a mesh size of less than 2 cm.

Due to their relationship with prey availability, elasmobranchs with an opportunistic diet can serve as indicators of changes in the marine community, thereby enhancing our understanding of the health of marine ecosystems. In this study, the Zearaja brevicaudata's trophic ecology was studied, by analysing its stomach contents, aiming to provide evidence of long-term changes in diet resulting from shifts in the structure of the Argentine Patagonian marine community in response to fishing pressure. Changes were evaluated according to catch area, predator size, sex, maturity over time. Moreover, the relationship between Zearaja brevicaudata's dietary shifts and the fishing effort of Merluccius hubbsi was investigated. Our results suggest a gradual replacement of the main prey species with lower trophic level species. Although no correlation was found with fishing effort, the diet of Z. brevicaudata over time reflected changes similar to those associated to the fishing exploitation of M. hubbsi in the Patagonian system. In this context, the Z. brevicaudata's diet emerges as a valuable tool for monitoring and assessing changes in the marine community. By serving as an indicator, Z. brevicaudata's diet provides crucial insights into the conservation status of the marine ecosystem, enabling informed management and conservation efforts. [ABSTRACT FROM AUTHOR]

The effects of discontinuing harmful fishery subsidies in Spain were analysed using a social accounting matrix. The study found that the removal of these subsidies would have negative consequences for the economy. Specifically, there would be a significant decline in the production value of marine resource industries, and industries dependent on fish and shellfish as inputs would experience increased production costs. The exports, mainly to EU countries, would also be impacted, and certain marine resource sectors would experience significant job losses. Fishing families would suffer the greatest reduction in income once subsidies are removed. However, there is potential to mitigate most of the negative impacts by redirecting the removed subsidies, as it is shown for the case of their redirection to research and development industries. The findings of this study provide valuable insights for EU policymakers in implementing specific policies to address the potential consequences on affected sectors, families, and employers as part of the next European strategy, Horizon 2021–2027. [ABSTRACT FROM AUTHOR]

AbstractAquaculture plays an important role in the world’s productive, social, and economic growth. The production of low-trophic-level fish such as Clupeids, aimed at the sustainable growth of the aquaculture industry, is a desirable and promising strategy, considering that low-trophic-level species represent approximately 30% of global fish production and contribute directly to worldwide food security. Clupeids, consisting mainly of herring, sardines, shads, and anchovies, form one of the main fisheries resources in the oceans, and the use of fish meal and fish oil to manufacture feed used to nourish fish in aquaculture also affects aquatic productivity through the capture of species, including small pelagic fish. The effects of overfishing on low-trophic-level species can have major impacts on marine ecosystems, and reducing the pressure on these natural stocks would be of extreme ecological importance. Aquaculture is an important tool for alleviating hunger and poverty in developing countries, providing a source of high-quality animal protein and generating employment and income. In Brazil, the cultivation of the Brazilian sardine Sardinella brasiliensis has been shown to be a viable alternative in marine fish farming due to its biological characteristics and economic and ecological importance. The present review addressed the interrelationship between fishing and the cultivation of S. brasiliensis, and how marine fish farming can be used as a compensatory tool in the supply of small marine pelagic fish threatened by overfishing in different regions of the world. [ABSTRACT FROM AUTHOR]

Simple Summary: In the Mediterranean region, teleost species are facing diverse challenges resulting from the combined effects of climate change, pollution, and overfishing. The survival of these species and the overall stability of the ecosystem are closely linked to their reproductive success and their capacity to produce healthy offspring. Teleost reproduction is a crucial aspect in aquaculture as well since it ensures the productivity of high-quality animal proteins as an alternative to overexploited wild stocks. Therefore, deep knowledge on the factors influencing the reproduction of species devoted to aquaculture at different levels is necessary to propose efficient management approaches, aiming to identify sustainable farming techniques. To attain this goal, it is initially necessary to comprehend the molecular and physiological mechanisms that regulate various levels of the reproductive process in a changing scenario. The use of model organisms allows scientists to test specific stressors without external interference, thanks to their availability, easier handling, and biological characteristics. However, caution is needed to avoid overestimating their applicability to other species. The present review aims to explore the current factors affecting reproduction in wild, farmed, and model teleosts. The Mediterranean region is facing several environmental changes and pollution issues. Teleosts are particularly sensitive to these challenges due to their intricate reproductive biology and reliance on specific environmental cues for successful reproduction. Wild populations struggle with the triad of climate change, environmental contamination, and overfishing, which can deeply affect reproductive success and population dynamics. In farmed species, abiotic factors affecting reproduction are easier to control, whereas finding alternatives to conventional diets for farmed teleosts is crucial for enhancing broodstock health, reproductive success, and the sustainability of the aquaculture sector. Addressing these challenges involves ongoing research into formulating specialized diets, optimizing feeding strategies, and developing alternative and sustainable feed ingredients. To achieve a deeper comprehension of these challenges, studies employing model species have emerged as pivotal tools. These models offer advantages in understanding reproductive mechanisms due to their well-defined physiology, genetic tractability, and ease of manipulation. Yet, while providing invaluable insights, their applicability to diverse species remains constrained by inherent variations across taxa and oversimplification of complex environmental interactions, thus limiting the extrapolation of the scientific findings. Bridging these gaps necessitates multidisciplinary approaches, emphasizing conservation efforts for wild species and tailored nutritional strategies for aquaculture, thereby fostering sustainable teleost reproduction in the Mediterranean. [ABSTRACT FROM AUTHOR]

The marine fisheries of Bangladesh have experienced an uncontrolled expansion of fishing over the last few decades. Consequently, most fish stocks became vulnerable to overfishing. Similar to many other fisheries, catch of white sardine (Escualosa thoracata) is rapidly declining. Therefore, three data‐limited approaches (length‐based Bayesian biomass analysis, LBB; length‐based spawning potential ratio, LB‐SPR; and Froese's length‐based indicators, LBIs) were used to estimate growth, mortality, and fisheries reference points to evaluate stock status of the white sardine fishery. Results revealed that the fishery is being overfished: F/M = 1.32 years−1 in LBB and 6.67 years−1 in LB‐SPR. However, the stock biomass is still good with B/B0 = 0.43 and B/BMSY = 1.20. Stock indicators revealed that the fishery was mainly targeting mature fishes, most of which were mega‐spawners (older, larger fish), which suggested stocks were recruitment overfished. Harvesting an optimum size range (6.57 to 8.03 cm) and reducing fishing mortality to a sustainable level (F = M) would sustain a healthy stock biomass. [ABSTRACT FROM AUTHOR]

The Spanish mackerel (Scomberomorus brasiliensis) is of high commercial value throughout its distribution. In Northeast Brazil, this important fishery resource has been under strong fishing pressure since the 1960s, with length composition changing between 1998–2001 and 2020–2022. Length frequency distributions, exploitation indicators, and gear selectivity indicated the effects of overfishing on stock size structure, with excessive withdrawal of spawners and reduced numbers of adults larger than 60 cm in catches. In addition, gear selectivity changed, with reduced size at first capture in the 40‐mm mesh. Our results indicated that the species is unsustainably exploited in the study area and suggested both growth and recruitment overfishing. [ABSTRACT FROM AUTHOR]

Marine species are widely shifting their distributions in response to global changes and it is commonly expected they will move northward and to greater depths to reach cooler, less disturbed habitats. However, local manifestations of global changes, anthropogenic pressures, and species characteristics may lead to unanticipated and varied responses by individual species. In this regard, the Celtic‐Biscay Shelf is a particularly interesting study system because it has historically been heavily fished and occurs at the interface between two distinct biogeographic provinces, its community thus comprised of species with diverse thermal preferenda. In the context of rapidly warming temperatures and intense fishery exploitation, we investigated the distribution shifts of 93 taxa (65 Actinopteri, 10 Elasmobranchii, 11 Cephalopoda, 5 Malacostraca, and 2 Bivalvia), which were sampled annually from 1997 to 2020 during a scientific bottom trawl survey. We used a set of 11 complementary spatial indices to quantify taxon distribution shifts over time. Then, we explored the relative effect of taxon abundance, fishing pressure, and climatic conditions on taxon's distribution shift when a significant shift was detected. We observed that 56% of the taxa significantly shifted. Not all taxa will necessarily shift northward and to deeper areas, as it is often expected. Two opposite patterns were identified: taxa either moving deeper and to the southeast, or moving closer to the surface and to the northwest. The main explanatory factors were climate change (short‐ and long‐term temperatures) and taxon abundance. Fishing pressure was the third, but still significant, explanatory factor of taxa of greater commercial importance. Our research highlights that taxa are displaying complex distribution shifts in response to the combined anthropogenic disturbances and underscores the need to conduct regional studies to better understand these responses at the ecosystem scale to develop more suitable management plans and policies. [ABSTRACT FROM AUTHOR]

Objective: The common whelk Buccinum undatum is of great commercial and ecological importance, but little information is known regarding the gear selectivity of the fishery. Understanding gear selectivity is key for the long‐term sustainability of a stock and has applications in stock assessments and fishery management. Methods: We investigated the effect of gear (pots) on the selectivity of catch within the common whelk commercial fishery through a mark–recapture study and comparative gear trials across Wales. The size composition of the population in the water was estimated by dividing the numbers at size brought onboard by the selectivity of the pots. The selectivity of experimental pots (commercial pots that were modified to catch a wider size range) was estimated by comparing the size composition of whelks caught in the experimental gear to the estimated size composition of the population. Result: Peak selectivity of commercial pots occurred around the current minimum landing size (65 mm total shell length) for common whelks, with selectivity sloping off gradually for larger individuals and rapidly for undersized individuals. Across regions, less than 30% of the catch from baited lay‐down pots was discarded. Experimental pots were found to have a more variable but generally dome‐shaped selectivity curve similar to that of the commercial pots. Conclusion: The fishery appears to be well designed, with gear successfully targeting the legal‐sized catch, which is promising for the conservation of the stock if discards have a high survival rate. Experimental gear is ideal for stock assessment purposes, and methods developed to estimate the selectivity of the experimental pots reduce the need for further intensive mark–recapture studies as fishing gear evolves over time. Impact statementThe common whelk is regarded as a data‐poor stock; other than total landings, little information is currently known about the fishery. This study used mark–recapture surveys and comparative gear trials to estimate the selectivity of whelk pots and to determine the composition of whelks in the population. Our findings will facilitate the ongoing development of management strategies for this commercially important species. [ABSTRACT FROM AUTHOR]

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A commercial fishery for the smooth hammerhead shark (Sphyrna zygaena) exists in the waters off northern Peru. Although international and domestic norms regulate this species, adult specimens are becoming rare. Monthly visits to four ports in the La Libertad region were made to measure S. zygaena landings and understand the present state of the fishery. We found that 92% of the specimens landed were juveniles or younger and that 10% of the original biomass remains in the fishery. This highlights that stricter regulations such as protecting breeding areas, establishing a legal catch length, and limiting the catch volume and fishing season are urgently needed to maintain a sustainable fishery. [ABSTRACT FROM AUTHOR]

Aim: Oceanic sharks play an important role in maintaining the stability and biodiversity of marine ecosystems, and yet they are among the most threatened taxa worldwide. Currently, large spatial‐scale distribution patterns and conservation gaps are poorly known for most species since they are challenging to study. To address the problem, we here use an integrated approach with an illustration with the blue shark (Prionace glauca), a common bycatch oceanic species. Location: Indo‐Western Pacific Ocean (IWPO). Methods: We first collated decades of species occurrences and marine environmental datasets from open‐access sources. We then applied ensembled species distribution models (SDMs) to predict its seasonal distributions and evaluated the model performance using true skill statistic (TSS) and area under the receiver‐operating characteristic curve (AUC). We finally conducted spatial analyses (e.g. bivariate hotspot analyses) to identify conservation gaps/opportunities based on the predicted distribution maps and two additional datasets, namely, marine protected areas (MPAs) and fishing effort. Results: (1) Both seasonal SDMs performed well (mean TSS > 0.8, AUC > 0.95), and the results suggested that blue sharks were widely distributed in the IWPO with some seasonal differences in ecological niches and distributions (mainly in the West Indian Ocean and the Northwest Pacific Ocean); (2) large MPAs and shark sanctuaries covered comparable, small portions (4%–9%) of blue shark habitats, but these locations (in MPAs and sanctuaries) varied between seasons; (3) fishery‐shark conflict hotspots also varied between seasons with some located in or close to large MPAs and sanctuaries. Main conclusions: We provide seasonal (cold vs. warm) distribution maps of blue sharks across the IWPO to advance their conservation and management. We highlight the importance of strengthening management both in and near large MPAs and shark sanctuaries. Our study contributes a feasible integrated approach to reveal seasonal distribution patterns and conservation opportunities for oceanic sharks. [ABSTRACT FROM AUTHOR]

White Crappie (Pomoxis annularis) and Black Crappie (P. nigromaculatus) were studied in three southeast Kansas reservoirs to assess exploitation and determine if current regulations were conducive for sustainable populations. Trap nets were used to sample crappie in Elk City Reservoir, Big Hill Reservoir, and Parsons City Lake. Crappie measuring 210 mm and greater received Floy FD-94 tags that served as entries for rewards to encourage tag reporting. Harvest and angler demographic information were collected when tags were reported. Postcard surveys and motion-sensed cameras were used in conjunction to estimate angler effort and reporting rate on Parsons City Lake. Annual exploitation rates (i.e., percent of fish harvested) determined by tag returns and corrected for nonreporting and tag loss were 28.3%, 21.8%, and 3.9% on Elk City Reservoir, Big Hill Reservoir, and Parsons City Lake, respectively. Overfishing was not occurring, so current statewide regulations were likely appropriate, and no changes may be necessary. [ABSTRACT FROM AUTHOR]

Where sea urchin harvest has been so intense that populations have drastically regressed, concerns have arisen about the effectiveness of harvesting management. According to the theory of phase transition in shallow rocky reefs between vegetated and barren habitats, sea urchin recruitment, a key population structuring process, seems hampered by some stabilizing feedback despite an end to local human harvest of sea urchins. To shed a light on predation effects on sea urchin recruits, a 27-day field experiment was conducted using mega-predator exclusion cages (40x40x40 cm, 1 cm in mesh size) in barren and turf substrates. To facilitate this, 672 recruits (1.1 ± 0.02 cm in size) reared under control conditions were positioned in groups of 42 in each experimental unit (n = 4). Exclusion of mega-predators had a significant effect regardless the substrate, since a higher number of recruits was found under cages both in turf and barren. However, the results showed that in uncaged treatments the size of recruits that survived was larger in turf than in barren, as in the former substrate predation had reduced the abundance of the smallest recruits, highlighting that mega-predator presence affects differently the size of the recruits that had survived depending on the substrate. Overall, these results provide valuable information to address restocking actions of sea urchin populations in overharvested areas, where algal turfs are widespread, and assist studies on habitat stability mechanisms. [ABSTRACT FROM AUTHOR]

Spawning potential ratio (SPR) is an important index used by fisheries biologists and managers to determine how a fishery should be harvested to prevent recruitment overfishing. In the southeastern Caspian Sea, Iran, 3430 common carp Cyprinus carpio were caught by beach seine in 2‐week intervals of two fishing seasons in 2019 and 2020. Fork length (FL) was measured to the nearest 1 cm. The age and maturity stage of 434 specimens, including 236 females and 198 males, were estimated by scale and gonad microscopic examinations. Estimated L∞ was 71.9 and K (growth constant) was 0.09. Instantaneous total mortality (Z) was 1.08, natural mortality (M) was 0.18, and fishing mortality (F) was 0.9. Estimated SPR at current fishing mortality (0.18) was lower than the reference point (0.4). Our findings indicated that fishing mortality should be reduced to F = 0.38 for C. carpio to meet the SPR reference point of 0.4. Further, higher minimum length limits should be set to reduce fishing mortality, and catch quotas for fishing cooperative corporations should be considered to meet the 40% SPR threshold. [ABSTRACT FROM AUTHOR]

The decline in walleye pollock (Gadus chalcogrammus) stocks in Korean waters is a major concern for fishery conservation and management. However, the causes and mechanisms of this collapse remain unclear. This study investigated the complex dynamics influencing the abundance of walleye pollocks in the East Sea of Korea over several decades, by analyzing data from long-term changes in biological factors including composition of length and sex, catch, and oceanographic condition. Prior to the mid-1980s, the catch ratio of juveniles was higher than that of adults, with a higher proportion of females in both juvenile and adult catches compared to males. Especially, high fishing pressure on female individuals can be an important factor contributing to declining reproduction. Consequently, after the mid-1980s, there was a sudden decline in juvenile pollock catches. In the late 1980s, there was a rapid increase in sea surface temperature (SST) in the spawning grounds, resulting in a decrease in both the duration of suitable temperature for spawning and the regional proportion for suitable spawning conditions. Consequently, the decline in pollock stocks after the late 1980s due to overfishing of pollock in the mid-1980s was further exacerbated by the effects of SST warming after the late 1980s. These findings highlight the impact of overfishing and environmental factors on pollock stocks and indicate the need for appropriate fishery management practices to ensure the sustainable use of fishery resources. [ABSTRACT FROM AUTHOR]

The trophic structure of ecosystems, reflecting biomass distribution across different levels, is paramount for understanding energy dynamics and community assemblages in marine environments. Typically, ecosystems devoid of external energy influx exhibit a bottom-heavy trophic pyramid, yet higher biomass systems often display a top heavy or concave distribution. Such structures are susceptible to alterations due to species turnover, trophic cascades, and anthropogenic impacts, particularly the phenomenon of ’Fishing down’ the food web. Recognizing the trophic structure as a simplified yet potent indicator, we identify the necessity for a standardized, expedient method to assess reef health—a criterion fulfilled by our Normalized Reef Status Index (NRSI). The NRSI offers a novel metric for scientists and conservation practitioners to augment traditional reef health assessments. Utilizing the NRSI, we assessed the ecological status of 346 reefs across the Mexican Pacific. Our results demonstrated that only reefs within Fully Protected areas conform to the concave trophic structure indicative of low human interference. In stark contrast, unprotected reefs exhibited a depleted trophic architecture, often devoid of apex predators. This depletion not only threatens coastal livelihoods and food security but also disrupts the delicate balance of marine ecosystems critical to sustaining global ecological functions. Through the NRSI, we provide a robust, scalable tool for ongoing monitoring and conservation efforts, underscoring the urgent need to address human-induced trophic disruptions.

Abstract Obtaining reliable estimates of the effective number of breeders (Nb) and generational effective population size (Ne) for fishery‐important species is challenging because they are often iteroparous and highly abundant, which can lead to bias and imprecision. However, recent advances in understanding of these parameters, as well as the development of bias correction methods, have improved the capacity to generate reliable estimates. We utilized samples of both single‐cohort young of the year and mixed‐age adults from two geographically and genetically isolated stocks of the Australasian snapper (Chrysophrys auratus) to investigate the feasibility of generating reliable Nb and Ne estimates for a fishery species. Snapper is an abundant, iteroparous broadcast spawning teleost that is heavily exploited by recreational and commercial fisheries. Employing neutral genome‐wide SNPs and the linkage‐disequilibrium method, we determined that the most reliable Nb and Ne estimates could be derived by genotyping at least 200 individuals from a single cohort. Although our estimates made from the mixed‐age adult samples were generally lower and less precise than those based on a single cohort, they still proved useful for understanding relative differences in genetic effective size between stocks. The correction formulas applied to adjust for biases due to physical linkage of loci and age structure resulted in substantial upward modifications of our estimates, demonstrating the importance of applying these bias corrections. Our findings provide important guidelines for estimating Nb and Ne for iteroparous species with large populations. This work also highlights the utility of samples originally collected for stock structure and stock assessment work for investigating genetic effective size in fishery‐important species.

Overfishing is the most significant threat facing sharks and rays. Given the growth in consumption of seafood, combined with the compounding effects of habitat loss, climate change, and pollution, there is a need to identify recovery paths, particularly in poorly managed and poorly monitored fisheries. Here, we document conservation through fisheries management success for 11 coastal sharks in US waters by comparing population trends through a Bayesian state-space model before and after the implementation of the 1993 Fisheries Management Plan for Sharks. We took advantage of the spatial and temporal gradients in fishing exposure and fisheries management in the Western Atlantic to analyze the effect on the Red List status of all 26 wide-ranging coastal sharks and rays. We show that extinction risk was greater where fishing pressure was higher, but this was offset by the strength of management engagement (indicated by strength of National and Regional Plan of Action for sharks and rays). The regional Red List Index (which tracks changes in extinction risk through time) declined in all regions until the 1980s but then improved in the North and Central Atlantic such that the average extinction risk is currently half that in the Southwest. Many sharks and rays are wide ranging, and successful fisheries management in one country can be undone by poorly regulated or unregulated fishing elsewhere. Our study underscores that well-enforced, science-based management of carefully monitored fisheries can achieve conservation success, even for slow-growing species.

The deep-sea Caribbean lobster (Metanephrops binghami) and the Norway lobster (Nephrops norvegicus) are Nephropidae species of high commercial interest. Although the first one still remains unexploited, the second is overexploited in the Mediterranean Sea. For effective fisheries management, size at sexual maturity is an essential indicator to protect immature individuals from exploitation. The estimation of this indicator can, however, be biased due to the difficulty of differentiating juveniles from adults by their size structure due to the natural process of molting. This study aims to estimate the size at sexual maturity of M. binghami and N. norvegicus females by comparing the effectiveness of the morphometric method versus the macroscopic evaluation of gonad maturity. Samples of M. binghami were collected from the Colombian Caribbean Sea in August and December 2009, March and May 2010, and August 2020 to May 2021. Samples of N. norvegicus were collected from the northwestern Mediterranean Sea from 2019 to 2022. Similar sizes at sexual maturity were found for M. binghami between the morphometric approach (ranging from 28.6 to 33.9 mm cephalothorax length, CL) and the gonadal staging approach (31.4 mm CL). Conversely, for N. norvegicus, the morphometric approach yielded higher measurements (between 27.2 and 30.4 mm CL) than the gonadal approach (26.0 mm CL). This discrepancy might stem from the intense fishing overexploitation conditions of N. norvergicus, leading to a physiological adaptation that enables earlier gonadal maturation at faster rates than morphometric adaptation. Further research is required to elucidate these discrepancies and the effect of overexploitation on physiological (i.e., mature gonads) and functional maturity (i.e., capacity to brood eggs at a larger size). [ABSTRACT FROM AUTHOR]

The Atlantic Ocean's little tunny is a priority for research by the International Commission for the Conservation of Atlantic Tunas (ICCAT). Limited studies exist on Northeast Atlantic Ocean stock dynamics, and conventional catch and abundance assessments are lacking. This study assesses the impacts of tuna purse seiner fish aggregating device (FAD) and free-swimming school (FSC) fishing and proposes models for assessment using ICCAT data aggregated into different time blocks. Applying JABBA (Just Another Bayesian Biomass Assessment) and CMSY++, model diagnostics indicate that the 2011–2021 time series arrangement offers more reliable stock status estimates. Both models show overfished status (biomass/biomass max sustainable yield [B/BMSY] < 0.5) from overfishing (fishing mortality/fishing mortality max sustainable yield [F/FMSY] > 1.5) by the FAD and FSC techniques. FAD catches have leveled with the stock's average surplus production (ASP), while FSC catches are closer to ASP. JABBA projections suggest BMSY for the stock in 2023–2024, with FSC and FAD catch limits of 3000–4000 tonnes. By implication, the stock may collapse from tuna purse seiner's FAD and FSC fishing unless catch limits are implemented. JABBA is most effective for little tunny with shorter catch and catch per unit effort (CPUE) data, while CMSY++ indicates overfished stock status with and without abundance indices. Both applied models are suitable for little tunny stock status prediction, but considering the abundance indices used in this study, management advice should be applied cautiously. [ABSTRACT FROM AUTHOR]

The biology and dynamics of sardina pilchardus and sardinella aurita from the east coast of Algeria were studied to compensate the lack of data concerning the exploitation of their stocks in this area. The von Bertalanffy growth equations were as follows: Lt = 21.58 [1-e-0.39 (t +0.086)] for S. pilchardus and Lt = 26.68 [1-e-0.41 (t +0.085)] for S. aurita. The equations of the length - weight relationship were TW = 0.0039 TL3.236 for S. pilchardus and TW = 0.005 TL3.134 for S. aurita. The lengths at first maturity (Lm50) were 11.61 and 13.54cm for S. pilchardus and S. aurita, respectively. The natural mortalities (M) were 0.46 year-1 for both species, while those of fishing mortality coefficients (F) were 1.49 year-1 for S. pilchardus and 1.41 year-1 for S. aurita. The results of the virtual population analysis (VPA) showed the existence of an overfishing status for both species. To limit the risk of stock collapse, we recommended adjusting the Fcurrent fishing effort factor to F0.1, it should be reduced by 65% for S. pilchardus and 60% for S. aurita; this would allow for resources renewal. as well as increasing the exploitable biomass of both stocks. [ABSTRACT FROM AUTHOR]

The ecosystem structure of a Mediterranean high-altitude artificial lake (Aoos Springs, Northwest Greece) was assessed and quantified using the Ecopath with Ecosim model. The artificial lake was created in 1990 for hydroelectric production and the fish fauna has been enriched across years due to deliberate or accidental fish stockings, as well as the introduction of the invasive pumpkinseed (Lepomis gibbosus), which may cause adverse effects on aquatic ecosystems and their biota. The model considered 20 species/taxa groups with biological data gathered during 2021–2022 from field surveys, interviews with recreational anglers and literature. The results revealed that the artificial lake of Aoos is a resilient ecosystem to unexpected events with low intensity of fisheries exploitation. The biomass of the introduced invasive species Lepomis gibbosus is low, due to the low biomass level of its diet, Chironomidae and zoobenthic organisms as well as other fish species. [ABSTRACT FROM AUTHOR]

Firmly cemented in history as a connector of people, a facilitator for trade and transport routes and a driver of culture and heritage, the ocean has directly influenced globalization, and humanity more generally, for generations. While the ocean was perhaps once viewed as infinite and insurmountable, globally our oceans, coasts and seas have experienced unprecedented change in recent decades with climate change, loss of biodiversity and overfishing among the challenges being addressed through contemporary ocean governance. Moreover, and crucially as we continue to strive for sustainable ocean futures, the global ocean is increasingly being recognized as a peopled space. This article explores the role of ocean literacy as we look towards achieving sustainable ocean futures. [ABSTRACT FROM AUTHOR]

Korea has implemented prohibitory regulations on fishing for particular periods (or seasons), areas, sexes, depths, and minimum lengths (or weights) for fish species, along with implementation of the Total Allowable Catch (TAC) system, for the management and protection of fishery resources in Korean waters. In this study, the ecological and economic effects of minimum capture size limits were analyzed for the sandfish Arctoscopus japonicus. Sandfish are currently mainly targeted by the East Sea Mid-sized Danish seine fishery, and the total length at first capture ( T L tc ) of the fishery is 14.9 cm, which is larger than the minimum permitted total length (TL 11 cm or less). Therefore, it seems that there is little chance of growth overfishing at present. However, recruitment overfishing occurs with a spawning potential ratio (SPR) of 18%. Therefore, it is likely that this will need to be reflected in Acceptable Biological Catch (ABC) settings for TAC management. If the current T L tc (14.9 cm) is considered to be a consequence of setting minimum capture size limits for the East Sea Mid-sized Danish seine fishery, the expected catch and fishing profit for cases without ( T L tc = 9 cm) and with ( T L tc = 14.9 cm) minimum capture size limits were 2204 mt (217,000 US$) and 2744 mt (270,000 US$), respectively. The establishment of the minimum capture size limit regulations showed an increase of approximately 25% in fish production and fishing profits. In addition, by testing several scenarios for the fishing intensity and the minimum capture size limits, we were able to compare the biomass of sandfish and the fishing profits of the East Sea Mid-sized Danish seine fishery after 15 years. We found that this approach was most effective in reducing the combined fishing intensities of juvenile and adult fish and more effective in reducing the fishing intensity for juveniles than for adult fish, thereby increasing the biomass and fishing profits of sandfish. These findings indicate that to recover populations and sustainably use sandfish, stocks should be managed through a holistic integrated approach that considers the ecosystem, which has been actively promoted by the Korean government in the third National Basic Plan for Fisheries Resources Management (2021–2025), rather than individually pursuing management policies such as the minimum size limit regulation, the Fisheries Resources Rebuilding Program, and the TAC management system. [ABSTRACT FROM AUTHOR]

During the last 50 years, the increase in the efforts of the longline fleet in the Eastern Pacific Ocean (EPO) resulted in an increase in the capture of the swordfish Xiphias gladius. We analyzed a historical database of swordfish catches (1980–2020) reported by the industrial longline fleet to the Inter-American Tuna Tropical Commission (IATTC), which contains catch and effort data aggregated in monthly quadrants of 5° × 5° in the EPO. The swordfish catch reported by the international longline fleets was analyzed to evaluate the spatiotemporal variation of the catch and the different phases through which this important fishery has gone through. Different statistical models such as the Generalized Additive Mixed Model (GAMM) and the breaks for additive season and trend BFAST algorithm were used for the decomposition of the time series. Results indicated that the effort directed towards the swordfish increased in recent years and that the highest catches occurred by Peru. The adjusted GAMM explained 80% of the total temporal variation of the swordfish catch per unit effort CPUE and had a 90% prediction efficiency. The BFAST algorithm found three break points in the time series of the standardized CPUE, points associated with abrupt changes, thus defining four distinct periods, all of them statistically significant. According to the BFAST model, the current trend of swordfish CPUE is upward. It is recommended to take this finding with caution to obtain the sustainable exploitation of the swordfish fishery resource. [ABSTRACT FROM AUTHOR]

The goal of this project is to assess the state of marine biodiversity in the Natura 2000 marine network in Spain and analyze the impact of fishing policies on it. The study focuses on three marine demarcations in Spain: North Atlantic, South Atlantic, and the Strait of Gibraltar and Alborán Sea. The research uses the DPSIR (Drivers of Change-Pressure-State-Impact-Response) framework, a multi-criteria analysis approach to understand the relationships between biodiversity loss, fishing, marine ecosystem integrity, and the provision of ecosystem services. Our results revealed a significant decline in biodiversity since 1985 in the four marine areas studied; this loss was more pronounced in the Gulf of Cadiz (in Andalusia) and less intense in the northern regions of Spain (Galicia and Asturias). This trend aligns with the global degradation of marine ecosystems and loss of biodiversity caused by human activities. The main drivers behind this decline are economic factors promoting industrial fishing and overexploitation. However, there has been a reduction in the industrial fishing fleet since the 2000s, supported by the European Maritime and Fisheries Fund for transitioning toward sustainable fishing methods. Despite the increase in regulations and the establishment of marine protected areas, these measures have not been effective enough to stop the loss of marine biodiversity. The results highlight the importance of combining administrative measures such as creating marine protected areas and implementing fisheries management regulations with the preservation of cultural services provided by these ecosystems. Successful governance models that involve collaboration between fishermen and decision-makers have been observed in northern Galicia and the Gulf of Cádiz. [ABSTRACT FROM AUTHOR]

Human impacts are dramatically changing ecological communities, motivating research on resilience. Tropical reefs are increasingly undergoing transitions to short algal turf, a successional community that mediates either recovery to coral by allowing recruitment or transitions to longer turf/macroalgae. Intense herbivory limits turf height; subsequently, overfishing erodes resilience of the desirable coral-dominated reef state. Increased sedimentation also erodes resilience through smothering and herbivory suppression. In spite of this critical role, most herbivory studies on tropical reefs focus on fishes, and the contribution of urchins remains under-studied. To test how different herbivory and sedimentation scenarios impact turf resilience, we experimentally simulated, in situ, four future overfishing scenarios derived from patterns of fish and urchin loss in other reef systems and two future sedimentation regimes. We found urchins were critical to short turf resilience, maintaining this state even with reduced fish herbivory and increased sediment. Further, urchins cleared sediment, facilitating fish herbivory. This study articulates the likelihood of increased reliance on urchins on impacted reefs in the Anthropocene. [ABSTRACT FROM AUTHOR]

Classic studies of marine overexploitation traditionally analyze cases of "fishing down the food web": turning to smaller species at lower trophic levels after depleting the larger top predators. Much less documented, however, is the preceding phase in which higher trophic level species, previously not exploited or consumed locally, are increasingly added to the catch. Worldwide, this phase happened centuries ago due to technological developments and thus passed before scientific scrutiny and conservation awareness arose, leaving it largely unstudied. Here, we combine a historical reconstruction of fishery with a relatively recent fishing monitoring program to document this early phase in the Parc National du Banc d'Arguin in Mauritania, a marine protected area in Mauritania, West Africa. Long-term trends in mean trophic level of exploited species and total catches provide evidence for an increasing fishing pressure toward the top of the food web, and suggest that the state of "fishing down the food web" is now happening in this ecosystem. This involves the recent intensive targeting of rays and sharks. We show that their contribution to the local economy is marginal compared with the traditionally fished species [ABSTRACT FROM AUTHOR]

Motorized trawling was banned off part of the Brazilian coast in 1990 due to environmental impacts, thus artisanal fishermen adopted large beach seines as an alternative. No impact assessments have been conducted on any species; therefore, we examined the life history and stock status of shorthead drum, Larimus breviceps, a primary bycatch in tropical shrimp fisheries. Between 2016 and 2017, 969 shorthead drum were collected and analyzed using ELEFAN‐based models. Females were larger, more abundant, and older than males. Capture rates of juvenile were high, and no mega‐spawners were found. Integrated stock assessment indicated slight overexploitation and growth overfishing. Increased yield per recruit was indicated by high length at first capture. Shorthead drum segregate ontogenetically by size. Growth, mortality, and longevity may be temperature‐influenced. We found that beach seine fisheries may impact shorthead drum by population depletion and potential disruptions to reproductive capacity and recommend further studies and management to improve sustainability. [ABSTRACT FROM AUTHOR]

The Critically Endangered Nubian Flapshell Turtle (Cyclanorbis elegans) is found in the White Nile River system in South Sudan and northern Uganda. Over the past few decades, its populations have sharply declined, primarily due to human-induced threats, leading to its near-extinction across almost its entire range. In this paper, we present the results of a comprehensive threat analysis undertaken to pinpoint the challenges confronting the species within its natural habitat, specifically in the only known sites where it currently exists. We aimed to develop a conceptual framework to understand causal relationships among driving forces, threats and the target species. This framework allows the visualisation and analysis of the web of intricate interactions that contribute to the species' decline and vulnerability. We convened a panel of experts who identified three primary direct threats to the Nubian Flapshell Turtle: (1) Sand mining (IUCN code 3.2); (2) Overfishing by native fishers and refugees (code 5.4) and (3) Habitat loss at nesting sites (code 7.3). Among these threats, overfishing had the largest geographical extension, the highest intensity and duration, while habitat loss occurred at the highest frequency. These threats varied significantly in intensity and frequency. Additionally, when assessing the overall magnitude of these threats, habitat loss and overfishing had the highest impact, with significantly higher scores compared to sand mining. Our experts also identified the underlying driving forces behind these threats: (1) Economic interests driving sand mining activities along the Nile; (2) The influence of civil conflict and refugee populations, which contribute to the demand for bushmeat; (3) the Chinese expatriates, that lead to overfishing; (4) The removal of bank vegetation serves as a catalyst for habitat loss at nesting sites. The resulting conceptual framework serves as a valuable tool for defining targeted conservation measures for each distinct threat. [ABSTRACT FROM AUTHOR]

Objective: Red Snapper Lutjanus campechanus is an iconic species in the southeast U.S. Atlantic Ocean, sought by both commercial and recreational fleets. Five stock assessments over the past quarter century have shown Red Snapper to be experiencing overfishing. Highly restricted landings since 2010 have been insufficient to end overfishing because fishing effort is not species specific but rather applies generally to a complex of reef‐associated species. Consequently, Red Snapper are discarded as bycatch when regulations prohibit their retention, and many of the discarded fish die from hook injury, barotrauma, or depredation. Methods: Here we developed a spatial population model of Red Snapper and the multispecies fishery that captures them in the southeast U.S. Atlantic. We then simulated and compared 25 different management measures that fall broadly into the categories of gear modifications, discard mortality mitigation, size limits, spatial approaches, or temporal approaches. Criteria for comparison address the management goals of decreasing dead discards, rebuilding the age structure, and increasing landings and spawning biomass. Result: We found that the most effective measures reduced fishing effort, either temporally or spatially, and that benefits could largely be obtained by focusing on the recreational fleet. Discard mortality mitigation (e.g., through use of descender devices) displayed a wide range in effectiveness depending on plausible levels of mortality reduction, but it addressed all management goals and in practice could be paired with other measures. A measure with restricted recreational effort combined with full retention of all fish caught showed the greatest potential to simultaneously rebuild the stock, increase landings, and eliminate dead discards. Conclusion: To end overfishing of Red Snapper as required by law, resource managers should reconsider the policy of unrestricted effort of the private recreational fleet to this multispecies fishery. The benefits of restricted effort would include increased catch rates, larger landed fish, and fewer dead discards. Impact statementWe used a spatial population model of Red Snapper in the U.S. Atlantic to compare various fishery management strategies. The most effective strategy restricted fishing effort of the private recreational fleet, with benefits that included increased abundance, increased catch rates, larger landed fish, and fewer dead discards. [ABSTRACT FROM AUTHOR]