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Endangered sharks and rays usually often lack basic information specific to conservation, such as population size. Previous studies have reconstructed shark and ray catch statistics between 1950 and 2019 for the southeast = south of Brazil, but lacking detail at the species level, because the catches were grouped by family, genus or even common name (e.g., skates and rays, Dasyatidae, Rhinobatos, Sphyrnidae, Squatinidae). In this study, we used proportions between species from scientific observer fishing trips and Dirichlet regression modelling to reclassify these categories. This model is a multivariate extension of beta regression and enables the modeling of asymmetric and heteroscedastic compositional data, allowing multinomial data to be obtained in a more informative way. The reconstruction of catches for unclassified data showed a massive dominance of the Squatinidae family until the late 1970s, when catches showed signs of decline. At the same time, the rays of the "emplastro" family showed a progressive increase from 2006 onwards. However, this scenario changed after the reclassification. The category Squatinidae was maintained almost exclusively by S. guggenheim, while 16 categories of species were observed within "emplastro" rays, many of which fall into "endangered", "vulnerable" and "critically endangered" criteria. These reconstructed series provide a more reliable scenario of the catches of thirty elasmobranch species in the southeast and south of Brazil and serve as baseline information for understanding the conservation status of these species. [ABSTRACT FROM AUTHOR]

Understanding how animals respond to stressors is critical for effective conservation. The present study aimed to evaluate the physiological recovery of the Shortnose Guitarfish, Zapteryx brevirostris after being incidentally captured by artisanal fleets and compared it to guitarfish with delayed mortality. Moreover, the study aimed to test the efficiency of a rehabilitation protocol for the species. To this end, individuals landed alive were transported to the rehabilitation facilities and kept in tanks under monitoring for 3 days. Physiological markers indicative of allostatic overload (i.e., lactate and phosphorus) and energy metabolism (i.e., glucose and β‐hydroxybutyrate) were assessed in the serum of the studied guitarfish: right after gillnet capture (i.e., post‐capture) and on rehabilitation (i.e., pre‐monitoring, post‐monitoring, as well as guitarfish that deceased during monitoring – post‐mortem). Results showed that the transportation and additional handling employed in the rehabilitation protocol did not increase the stress response, pointing to its potential efficacy in recovering debilitated, incidentally caught guitarfish before release. As for recovery success of monitored guitarfish, lactic acidosis was fully reverted after a 3‐day rest period, as was allostatic overload. The same was not observed in recovery failure. Correlation tests revealed key relationships between physiological markers, shedding light on how physiological pathways help guitarfish cope with capture and handling stress. This study highlights the valuable application of conservation physiology principles to fisheries management of this endemic and threatened guitarfish species. [ABSTRACT FROM AUTHOR]

Fisheries-dependent data and information gathered through fisheries-related scientific surveys can significantly contribute to research on the patterns and processes underlying marine biological invasions and their interactions with fisheries. This study presents an overview of the presence of non-native fish species in the North Aegean Sea, offering insights into their distributions and impact on fisheries. The findings are based on a comprehensive compilation of commercial fisheries-dependent and scientific survey data collected in Greece from 2016 to 2023, along with a systematic review of the international scientific literature. The study resulted in the documentation of the presence of 37 nonnative fish species, including several recorded for the first time in the area. The results suggest that non-native fish species invasions in the North Aegean Sea are dynamic. Although most species were classified as casual, and the frequencies of occurrence as well as the quantities in commercial fisheries catches of established species are smaller than in the South Aegean Sea, species introductions and the extent of occurrence and area of occupancy of several species have been increasing since the 2000s. The significance of non-native fish species is becoming increasingly relevant to commercial fisheries in the study area. This is particularly evident in the Northeastern Aegean Sea, where catches of non-native species are on the rise, and new species with potential commercial value have emerged in recent years. [ABSTRACT FROM AUTHOR]

With a focus on seafood industries, this study provides a framework for economic contribution assessments, outlines Virginia's seafood supply chain components, and evaluates the direct, indirect, and induced economic impacts of Virginia's seafood industry in 2019. Utilizing an analysis-by-parts method in IMPLAN, primary expenditure data from watermen, aquaculture farmers, processors, and distributors were collected through surveys. The efficacy of obtaining primary data through stakeholder surveys heavily relies on the investigator's interpersonal skills to establish trust and elucidate the study's benefits, particularly its potential to inform policy decisions. In 2019, the Virginia seafood industry's estimated total economic contributions amounted to USD 1.1 billion, supporting 7187 individuals. This impact encompasses 6050 direct jobs, 523 indirect jobs, and 614 induced jobs, primarily benefiting watermen and coastal communities. Furthermore, the industry's influence extends beyond its immediate economic sphere, supporting diverse sectors such as polystyrene foam manufacturing, boat building, sporting and athletic goods, and commercial and industrial machinery. Wages and salaries disbursed throughout the seafood supply chain ripple to Virginia's economy, benefiting nondepository credit intermediation, owner-occupied dwellings, and real estate sectors. Future research focusing on seafood sales in restaurants and retail outlets will complete the understanding of the seafood industry's broader economic impact on the state. [ABSTRACT FROM AUTHOR]

Coregonus populations across their Holarctic range have often undergone unexplained collapses. Here, we document causes of collapse for two of the largest Coregonus populations in the world, cisco (C. artedi) in Green Bay, Lake Michigan, and Saginaw Bay, Lake Huron, during the 1950s. We used simulation models, rank‐order correlations, and historical literature to evaluate effects of overfishing, interactions with introduced rainbow smelt (Osmerus mordax), and overwinter bottom hypoxia on both cisco populations. Fully selected exploitation rates for cisco were alarmingly high (0.82–0.84), correlations and anecdotal evidence suggested negative interactions with rainbow smelt, and extensive areas of hypoxia coincident with cisco declines suggested incubation of cisco embryos was impaired regionally. Our findings suggested that negative effects of rainbow smelt were mainly responsible for the cisco population collapse in Green Bay and that overfishing and hypoxia had suppressed the Saginaw Bay cisco population before rainbow smelt caused its final collapse. [ABSTRACT FROM AUTHOR]

Coastal wetlands in San Diego County have experienced a significant decline in their extent over the past century due to erosion, sea-level rise, and development. Understanding the historical and current conditions of these wetlands is essential for effective management and restoration efforts. Furthermore, assessing the economic value of the ecosystem services provided by these wetlands is crucial for making informed decisions regarding their conservation and restoration. This paper presents a detailed valuation of two ecosystem services provided by San Diego County wetlands: nursery habitats for California halibut and carbon sequestration through blue carbon ecosystems. The valuation is based on existing scientific literature and government reports, and a Monte Carlo simulation is employed to account for the uncertainties associated with the complex and dynamic nature of coastal wetlands. The results indicate that these wetlands provide substantial economic benefits to the California halibut commercial fishery, valued at almost $998 thousand annually. The net present value analysis suggests that these wetlands could generate over $30.7 million in net benefits to the commercial fishery through the end of the century, assuming the habitats remain intact. Additionally, the wetlands contribute almost $5 million annually in natural capital through the production of juvenile California halibut. Utilizing a social cost of carbon value of $120/metric ton of CO2, local eelgrass beds, salt marshes, and mudflats are valued at over $1.6 million annually, with over 50% coming from eelgrass beds. The net present value analysis suggests that these wetlands could generate over $50 million in net benefits via carbon sequestration through the end of the century, assuming the habitats remain intact. This detailed valuation approach provides valuable information for policymakers and the public, facilitating better decision-making and increased awareness of the importance of protecting and restoring coastal wetland ecosystems for their ecological and economic contributions.See full project here: https://storymaps.arcgis.com/stories/d3456f12100047b2a979df40a59c8357

Despite progress in the management of assessed fish populations, many countries lag behind international commitments to restore overexploited stocks to healthy abundances. Here we use a mixed‐methods positive deviance approach, also known as 'bright spot' analysis, to understand what drives the successful governance of exploited species by learning from positive outliers, or 'deviants'. We use Canada as a case study, identifying factors driving the abundance of 230 commercially exploited fish and invertebrate populations, of which only 28% were classified at healthy abundance in 2022. We first applied a generalized linear model to test how diverse socio‐ecological fishery attributes relate to stock health. We found healthier stocks are positively and significantly correlated with certain management regions, more selective gears, eco‐certification, and high fishery value. Counterintuitively, healthier stocks were also associated with high inherent fishing vulnerability and the absence of reference points. We then used fishery expert surveys and interviews to investigate the social and institutional characteristics of stocks healthier than expected, given their circumstances. We found that fisheries targeting these positive outliers have lower conflict among users, balanced stakeholder involvement in data collection and decision‐making, and improved accounting of mortality sources. Lessons from these positive deviants can be applied to improve underperforming management systems that are struggling to reverse overexploitation in Canada and elsewhere. More generally, we suggest that a positive deviance approach, already used in public health, could be a promising tool to learn about successful fisheries management interventions, and the diverse actors responsible for ensuring these interventions are successful. [ABSTRACT FROM AUTHOR]

1. The Northern Argentine continental shelf is a sea turtle feeding ground that overlaps with important fisheries. Few studies assessed bycatch impact, especially on commercial vessels. 2. This work documents sea turtles' bycatch, fishery involved, species captured and crew actions. 3. Bycatch in four fisheries were registered at the 107 interviews to fishers conducted between 2021 and 2023, showing the urgency to research bottom trawling for demersal multi‐species. Fishers frequently recognize Caretta caretta, and positive and negative practices towards animals have been documented on‐board. 4. These results will help focus researches on fisheries with the greatest impact on sea turtles in the region. They also underscore the necessity for implementing commercial vessel monitoring programmes and improving on‐board handling practices. [ABSTRACT FROM AUTHOR]

The large-scale production and economy of French freshwater fisheries is not documented in the scientific literature. This article fills this knowledge gap by synthesizing the data collected since the post-war period, including a large part of the grey literature. France presents a wide variety of surface waters, benefiting from a reduction in pollution and a growing population with an emphasis on leisure activities and on locally sourced food products. Despite this favorable geographical, ecological and human situation, French freshwater fisheries have been in decline since the mid-1970s with a chronically negative trade balance for aquatic products. During this period, numbers of commercial fishers have decreased three-fold due to their affiliation to an agricultural status, and to their dependence on migratory species such as eel, shad and lamprey, which are all in decline. Simultaneously, numbers of anglers have also seen a slow but continuous decline, cushioned somewhat in the last 10 years thanks to the creation of sub-annual fishing cards and the expansion of the total to include the younger classes. Vestiges of a non-commercial fishery, similar to recreational subsistence fishing and employing gear such as dip nets, traps, long lines or even gillnets, have been maintained in a much reduced state around large rivers as well as in the marshes and estuaries of the Atlantic coast. In this detailed study of these different categories of fishing practices in the mid-2010s, we estimate numbers of fishers at 2 million active anglers, 4000 subsistence fishers, and 400 commercial fishers. Their catches are roughly 7600, 200 and 1200 tonnes/year, respectively, for a total of 9000 tonnes/year. The major part of the overall economic worth, estimated at 980,000 K€, is attributable to recreational fishers (anglers). [ABSTRACT FROM AUTHOR]

Crowded seas are becoming a pressing management problem with the increased development of offshore renewable energy (ORE) to combat climate change. Marine ecosystems are complex and varied; therefore, we need new tools to help rapidly increase our understanding of how they are likely to change with both climate and anthropogenic changes. This study uses a pragmatic data‐driven Bayesian network approach to capture the patterns of ecosystem complexity and reveal trends of ecosystem drivers (i.e. indicators) important to ecosystem functioning across space and over time. The ecosystem approach assessed physical and biological indicators and their influence on population (abundance/productivity) trends in four regions with contrasting habitats of the North Sea within the last 30 years (1990–2019). What‐if scenarios were conducted to examine species/functional group responses to physical (temperature and stratification) representing climate and large‐scale ORE development effects, as well as anthropogenic (fishing) changes. Clear patterns were revealed, including temporal trends of the dynamic nature of bottom‐up effects driven by physical change versus top‐down effects driven by fishing across trophic levels and habitat types. All four regions are influenced by both effects; however, the dominance of effects was dependent on region: Shetland and Orkney (bottom‐up driven), southern North Sea (top‐down driven). In general, regions with stronger bottom‐up effects showed increasing population trends whereas those with stronger top‐down effects, decreasing trends. Our findings also suggest that some species are much better indicators of either bottom‐up (e.g. zooplankton), top‐down effects (e.g. fish) or both (e.g. grey seal), but the strength of indicator is dependent on habitat type. The habitat‐specific results provide better understanding of what type of ecosystem change they are indicating (physical or biophysical) and therefore indicators that assess both ecosystem status and resilience, ensuring a more strategic and integrated evaluation of trade‐offs for future sustainable management of our shallow seas. [ABSTRACT FROM AUTHOR]

Ecological models are used to understand where fishing vessels operate, improving fisheries management success. The ideal free distribution (IFD) predicts equalization of catch across locations in response to distributions of fish and competing vessels. We applied the IFD as a null model to investigate the movement and catch per vessel (CPUE) of the sockeye salmon drift gillnet fleet in Bristol Bay, AK, from 1980 to 2019. The IFD prediction of equal CPUE across areas was not supported, so we explored violations of two assumptions of the theory. We categorized each vessel according to its mobility, highlighting the "free to move" assumption, and found that when we removed nonmobile vessels, some districts had fewer vessels than predicted from their high CPUE. We examined the "equal competitive ability" assumption by calculating the average CPUE, relative to success of other vessels. The underutilization of profitable districts persisted. Overall, the fleet underused high CPUE areas when considering differences in mobility and relative fishing success, indicating that unmeasured safety concerns, travel costs, knowledge of fishing grounds, or other factors could be preventing an IFD. [ABSTRACT FROM AUTHOR]

Hector's dolphin (Cephalorhynchus hectori) is an endangered species endemic to the coastal waters of Aotearoa New Zealand. To address the unsustainable bycatch of Hector's dolphins, restrictions on commercial gillnetting within 4 nautical miles of the coast were implemented in 2008, covering most of the South Island's east and south coasts.A small subpopulation of Hector's dolphins, estimated at 42 (95% CI: 19–92) in 2012, is located off Dunedin, on the south‐east coast of the South Island. It is known from other locations that Hector's dolphins are distributed well beyond 4 nautical miles from the coast and hence are vulnerable to ongoing gillnetting.In this study, a combination of boat‐based surveys, passive acoustic monitoring (PAM) and analysis of fishing effort were used to generate an up‐to‐date abundance estimate for Hector's dolphins off Dunedin and assess their vulnerability to commercial fishing. In the summer of 2021, abundance was estimated at 41 individuals (95% CI = 31–54), providing no evidence for population change since 2012.Analysis of visual sighting data indicated ongoing overlap between Hector's dolphins and commercial fishing effort. Using PAM, Hector's dolphins were detected on 94% of days at a location approximately 0.3 nautical miles from the coast, suggesting that shallow waters provide critical habitat for these dolphins year‐round. At an offshore mooring, approximately 4.5 nautical miles from the coast and therefore outside the area in which gillnetting is prohibited, detections were made on 35% of days, indicating potential for direct overlap with commercial fisheries.The inherent vulnerability of small populations to extinction highlights the need to take a precautionary approach to the management of Dunedin's Hector's dolphins if population recovery is to be facilitated. [ABSTRACT FROM AUTHOR]

We investigate the impact of health insurance subsidies on a US commercial fishing fleet. Prior to the passage of the Affordable Care Act, members of North Carolina's fleet showed different preferences for the private purchase of health insurance, with higher-income and offshore-active commercial fishermen disproportionately likely to have health insurance and pay private insurance premiums. We find that the act has largely eliminated that disparity. Lower-income and inshore commercial fishermen are now largely caught up to the rest of the fleet in terms of insurance coverage. We propose that the act's subsidies for insurance premiums are the cause of these changes. [ABSTRACT FROM AUTHOR]

Using a panel dataset of commercial fisheries in the Gulf of Mexico, we attempt to separately identify the moral hazard and self‐selection effects of property insurance coverage among commercial fishers. We use captains' propensity to take fishing trips under adverse weather conditions as a proxy for their private information; these data are available to us, but not to insurers. We find that vessels with higher long‐term exposure to risk are significantly less likely to be insured, suggesting potential advantageous selection. However, this relationship dissipates once we control for information likely known to the insurer. Finally, using a Heckit estimator, we find evidence of moral hazard: insured captains take more risks at sea. [ABSTRACT FROM AUTHOR]

Fisheries-dependent data and information gathered through fisheries-related scientific surveys can significantly contribute to research on the patterns and processes underlying marine biological invasions and their interactions with fisheries. This study presents an overview of the presence of non-native fish species in the North Aegean Sea, offering insights into their distributions and impact on fisheries. The findings are based on a comprehensive compilation of commercial fisheries-dependent and scientific survey data collected in Greece from 2016 to 2023, along with a systematic review of the international scientific literature. The study resulted in the documentation of the presence of 37 non-native fish species, including several recorded for the first time in the area. The results suggest that non-native fish species invasions in the North Aegean Sea are dynamic. Although most species were classified as casual, and the frequencies of occurrence as well as the quantities in commercial fisheries catches of established species are smaller than in the South Aegean Sea, species introductions and the extent of occurrence and area of occupancy of several species have been increasing since the 2000s. The significance of non-native fish species is becoming increasingly relevant to commercial fisheries in the study area. This is particularly evident in the Northeastern Aegean Sea, where catches of non-native species are on the rise, and new species with potential commercial value have emerged in recent years.

The status of federally managed fisheries in the United States is well monitored, but the condition of other marine fisheries, whether state‐managed, territory‐managed or unmanaged, is less understood and often unknown. We used expert surveys to characterize the management systems of non‐federally managed fisheries in US coastal marine states and overseas territories. For 311 fisheries, we estimated an overall Fisheries Management Index (FMI) and a qualitative stock status score. These measures were positively correlated, and while a wide range of research, management, enforcement and socioeconomic criteria were partially met (FMI ≥ 0.5) for 66% of fisheries, stock status was considered as partially acceptable (score ≥ 0.5) for only 45% of fisheries and acceptable (score = 1) for only 16% of fisheries. Higher FMI was typically observed in fisheries with greater commercial landed weight, value, or greater recreational catches. Fisheries from continental states had higher FMI than those from overseas territories. Invertebrates and diadromous fish species had higher FMI on average compared to those of marine fishes. Extrapolating results for surveyed fisheries to nearly 2000 non‐federally managed US fisheries while stratifying by state and importance designation (based on commercial, recreational, cultural or ecological importance), we estimate a mean overall FMI of 0.48, and estimate that only 19% of fisheries have a reliable estimate of stock status available; both measures are lower than similar estimates for federally managed fisheries. Funding or capacity constraints and information or data limitations were identified as common challenges faced by state agencies in managing fisheries under their jurisdiction. [ABSTRACT FROM AUTHOR]

Observational evidence shows marine species are shifting their geographic distribution in response to warming ocean temperatures. These shifts have implications for the US fisheries and seafood consumers. The analysis presented here employs a two-stage inverse demand model to estimate the consumer welfare impacts of projected increases or decreases in commercial landings for 16 US fisheries from 2021 to 2100, based on the predicted changes in thermally available habitat. The fisheries analyzed together account for 56% of the current US commercial fishing revenues. The analysis compares welfare impacts under two climate scenarios: a high emissions case that assumes limited efforts to reduce atmospheric greenhouse gas and a low emissions case that assumes more stringent mitigation. The present value of consumer surplus impacts when discounted at 3% is a net loss of $2.1 billion (2018 US$) in the low emissions case and $4.2 billion in the high emissions scenario. Projected annual losses reach $278-901 million by 2100.

With a focus on seafood industries, this study provides a framework for economic contribution assessments, outlines Virginia’s seafood supply chain components, and evaluates the direct, indirect, and induced economic impacts of Virginia’s seafood industry in 2019. Utilizing an analysis-by-parts method in IMPLAN, primary expenditure data from watermen, aquaculture farmers, processors, and distributors were collected through surveys. The efficacy of obtaining primary data through stakeholder surveys heavily relies on the investigator’s interpersonal skills to establish trust and elucidate the study’s benefits, particularly its potential to inform policy decisions. In 2019, the Virginia seafood industry’s estimated total economic contributions amounted to USD 1.1 billion, supporting 7187 individuals. This impact encompasses 6050 direct jobs, 523 indirect jobs, and 614 induced jobs, primarily benefiting watermen and coastal communities. Furthermore, the industry’s influence extends beyond its immediate economic sphere, supporting diverse sectors such as polystyrene foam manufacturing, boat building, sporting and athletic goods, and commercial and industrial machinery. Wages and salaries disbursed throughout the seafood supply chain ripple to Virginia’s economy, benefiting nondepository credit intermediation, owner-occupied dwellings, and real estate sectors. Future research focusing on seafood sales in restaurants and retail outlets will complete the understanding of the seafood industry’s broader economic impact on the state.

The invasive round goby (Neogobius melanostomus) was established in the coastal waters of the Baltic Sea in the early 1990s. The first observation of the species in Latvian waters was in 2004. In the intervening period, the population grew, the species became of significance for local fisheries, and it likely impacted the local ecosystem in the Baltic Sea. In this study, we characterize the spatial–temporal population development of round goby in Latvian coastal waters using data from three different scientific and fisheries-independent surveys. We also include data from commercial fisheries landings to describe the fisheries targeting the species. Our results suggest an exponential increase in population numbers of round goby in Latvian waters, peaking in 2018, followed by a sharp decline. This observation is also supported by data from commercial fisheries landings. We suggest that intensive commercial fishing had a considerable impact on the rapid decline of the species, but that the decline was potentially amplified through a wider scale decline, as observed in many areas of the Baltic Sea. The results of this study contribute to the knowledge base on the species and how fisheries can aid in limiting the development of invasive fish populations. Based on the results of the study, we also provide recommendations for better future monitoring of the species in the coastal waters of the Baltic Sea. [ABSTRACT FROM AUTHOR]

Sharks and rays are among the most threatened vertebrates, mostly due to commercial fisheries. Data on incidental capture is sparse, but it is estimated that about 50% of reported global catches of elasmobranchs are from bycatch. Elasmobranchs are captured in a variety of fishing gear throughout the world. One promising strategy to minimize incidental catches is the release of live sharks and rays. However, so far, no critical analysis had been carried out to assess the importance of release as a measure to mitigate the impacts of bycatch. Results indicated that despite onboard releases being cited in Plans of Action (along ZEEs) and recommendations/regulations of Regional Fisheries Management Commissions (in international waters), this measure is treated as secondary and has voluntary adherence, which can significantly reduce its efficiency. Moreover, among the Best Fishing Practice Manuals currently available, although release is cited as a priority, most of them do not consider the dynamics of the location/fishing modality for which it was developed. A change on how release is perceived is needed to prioritize this conservation strategy, as well as its potential as a social tool to reduce the impacts of bycatch on sharks and rays. [ABSTRACT FROM AUTHOR]

The existence of a commercial fishery in a coastal community is often promoted by the tourism sector as a key feature to encourage visits by tourists. However, the contribution of fisheries to tourism in coastal communities in the economic literature is unclear, with mixed results from previous studies. In this study, we examine the counterfactual—how would tourism change in the absence of fishing, and how would this affect benefits to tourists and the local economy. We use a contingent behavior travel cost model, combining revealed and stated preference data, to estimate these changes for Mooloolaba, a coastal fishing town in the Sunshine Coast region of Queensland, Australia. We find that the fishing industry and related provision of local seafood generate $6 million in welfare gains to visitors. We further estimate that it is directly responsible for 19% of the total number of days visiting the town, contributing an additional $8 million per year through tourism related expenditure. Given the importance of the fishing industry to the tourism sector in coastal communities, there is a need for the tourism industry to engage in the fisheries management process. [ABSTRACT FROM AUTHOR]

The giant red sea cucumber (Apostichopus californicus) fishery in BC, Canada, is considered sustainable by managers but not by many harvesters. In 1997, the Kitasoo/Xai'xais First Nation began experimental fishing areas (EFAs) at Tolmie Channel and Laredo Inlet to test the effects of different exploitation rates on sea cucumber populations and determine what harvest levels are sustainable. These EFAs were annually surveyed by dive transects and subsequently harvested from 1998 to 2018. Bayesian surplus production models developed in 2011 indicated that the fishery was sustainable, after which the fishery changed from annual to 3-year rotational harvests. Here, we develop updated models to estimate the sustainability of the fishery using all currently available EFA data, including direct estimates of unfished biomass. Our models suggest that the fishery is likely to persist for 175 years at the current harvest rate annually or rotationally, though such long-term projections are likely inaccurate. We present methodology to generate scientific advice for the process of determining a maximum sustainable exploitation rate in the form of crash rate analysis. [ABSTRACT FROM AUTHOR]

Smartphones are increasingly the most common type of mobile phone used throughout the world, offering users the ability to browse the internet and access mobile applications. Smartphones are also often equipped with high definition digital cameras, accelerometers, gyroscopes, and GPS. They can, therefore, facilitate the collection and dissemination of data, often through purpose designed applications (apps). As a result, numerous apps have been developed for use in wild capture fisheries. These apps have been designed for a number of purposes including for data collection, providing information to fishers, being linked to value chains and post-harvest practices and for uses linked to employment, legislation and safety. These apps are used across the world from large commercialized fisheries to small scale fisheries. In the latter, apps have the potential to bridge a technology gap, possibly replicating the functions of multiple pieces of hardware such as are used on larger vessels. This paper presents results from a narrative literature review to provide a synthesis of smart phone apps currently available for use by commercial fishers. 84 smartphone apps were identified as being currently available for use in commercial wild capture fisheries throughout the world. Smartphone apps were available for a number of uses but they were predominantly used for data collection and reporting. While this review provides an important overview of the extent of app use in commercial wild capture fisheries there remains potential for future work to improve understanding of how beneficial app use is and what it is that encourages app use and determines an app as being 'successful'. [ABSTRACT FROM AUTHOR]

Increasing depletion of fish stocks in the Mediterranean Sea intensifies conflicts between fisheries and marine mammals, such as the common bottlenose dolphin (Tursiops truncatus, Montagu, 1821). To increase the knowledge of such interactions in the eastern Mediterranean Sea, fishing activities of commercial fisheries and biomass of fish families targeted by fisheries and T. truncatus were analysed to identify areas that are more likely to be affected by these conflicts in the Dodecanese region of Greece. The area with the highest risk of conflict is located between Kos and Leros islands and the southwest coast of Turkey, which is mainly caused by trawl fishing activities. The presence of Sparidae, Merlucciidae, Mullidae and other unspecified fish families increased the likelihood of conflicts. Our applied method and results can be used to improve fishing regulations and management to diminish similar conflicts elsewhere in the world. [ABSTRACT FROM AUTHOR]

Fishery managers throughout the upper Laurentian Great Lakes are currently faced with a two-decade decline in abundance and harvest of lake whitefish Coregonus clupeaformis stocks. We used multivariate auto-regressive state-space (MARSS) models to develop long-term (90-year; 1929–2018) time-series of lake whitefish relative abundance based on commercial catch- per -effort (CPE) data for 13 statistical districts in State of Michigan waters, including 1836 and 1842 Treaty ceded waters, of Lakes Superior, Michigan, and Huron. CPE time-series were used to estimate historical baseline conditions, which were compared to more recent conditions, specifically with reference to select regulatory, environmental, and ecological conditions in each lake and fishing intensity. Population growth rates suggested that lake whitefish stocks responded: (1) negatively to high levels of harvest and expansion of sea lamprey Petromyzon marinus populations during the early-1900s; (2) positively to commercial fishery regulation and sea lamprey control during the late-1950s and early-1960s; and (3) negatively to establishment of dreissenid mussels Dreissena spp. in Lakes Michigan and Huron by 2005 and the recent period of low productivity in all three lakes since the mid- to late-2000s. When placed in a historical context, the most recent (2011–2018) lake whitefish abundances are low, intermediate, and high in 31 %, 46 %, and 23 % of all districts examined. Although environmental and ecological conditions likely drove recent declines, correlation analysis suggested that higher levels of fishing intensity were associated with greater district-specific declines in abundance during the last two decades (1999–2016), a period characterized by lower overall productivity and limited recruitment in most lake whitefish stocks. [ABSTRACT FROM AUTHOR]

While considerable scientific uncertainties persist for mesopelagic ecosystems, the fishing industry has developed a great interest in commercial exploitation with improved technologies as part of their search for new sources of feed for fishmeal and fish oil for aquaculture, which will intensify with the planet's growing population. The multiple uncertainties surrounding the ecosystem structure and particularly the size of biomass, hinder a good understanding of the risks associated with large‐scale exploitation, which is needed for a management framework for sustainable ocean uses. Despite concerns regarding irreversible losses triggered by commercial fishing, work exploring the vulnerability of mesopelagic fish to harvesting is largely missing. This study investigates the economic feasibility of mesopelagic fishing which is the primary driver for any possible future expansion. Using very limited information currently available, we conduct a high‐level assessment focusing on key ecological and economic interactions and develop an initial understanding of the economic feasibility of commercial harvesting for mesopelagic fish in the coming years. We conduct simulations using a classical bioeconomic model that captures two species groups, mesopelagic and epipelagic fish, using a wide range of price and cost parameters. We analyze different scenarios for the economic profitability of the fishery in a regional fishery management context. The results of our study highlight the importance of better understanding key biological and ecological mechanisms and parameters which can in turn help inform policies aimed at protecting the mesopelagic. Recommendations for Resource Managers: A high‐level assessment focusing on key ecological and economic interactions suggests that commercial harvesting in the Ocean Twilight Zone with improved technologies may become economically feasible in the coming years.It is imperative to better understand key biological and ecological mechanisms of the mesopelagic ecosystems to facilitate the development of management institutions and proactive policies to ensure sustainability.The scarcity of natural science data on mesopelagic ecosystems is echoed by a paucity of information on the economic and socioecological implications of commercial‐scale mesopelagic fisheries. Considering pressure for commercial exploitation to meet the world's increasing demand for fishmeal and fish oil, it is more relevant than ever to understand relevant trade‐offs to inform management decision‐making. [ABSTRACT FROM AUTHOR]

The invasive round goby (Neogobius melanostomus) was established in the coastal waters of the Baltic Sea in the early 1990s. The first observation of the species in Latvian waters was in 2004. In the intervening period, the population grew, the species became of significance for local fisheries, and it likely impacted the local ecosystem in the Baltic Sea. In this study, we characterize the spatial–temporal population development of round goby in Latvian coastal waters using data from three different scientific and fisheries-independent surveys. We also include data from commercial fisheries landings to describe the fisheries targeting the species. Our results suggest an exponential increase in population numbers of round goby in Latvian waters, peaking in 2018, followed by a sharp decline. This observation is also supported by data from commercial fisheries landings. We suggest that intensive commercial fishing had a considerable impact on the rapid decline of the species, but that the decline was potentially amplified through a wider scale decline, as observed in many areas of the Baltic Sea. The results of this study contribute to the knowledge base on the species and how fisheries can aid in limiting the development of invasive fish populations. Based on the results of the study, we also provide recommendations for better future monitoring of the species in the coastal waters of the Baltic Sea.

The spatial–temporal distribution of cetacean species often overlaps with fishing practices in the Mediterranean, having direct and indirect consequences. This is the first long‐term study focusing on the effects of fisheries on the behavior of T. truncatus in Montenegro. Focal group scan sampling was used during surveys between September 2016 and August 2020 to create transition probability matrices using first‐order Markov chains for behavioral states in both control (absence of fishery practices) and impact chains (presence of fishery practices). Despite the low number of dolphin‐fishery interactions in Montenegro, results revealed that the behavioral budgets of T. truncatus were significantly altered both for commercial and artisanal fisheries. However, the magnitude of the threat differed between practices, with commercial fisheries altering three out of the four behaviors in the behavioral budget while artisanal fisheries altered just one. Significant behavioral changes due to disturbance can have negative consequences on the energy budget of individuals and while the Montenegrin fishing fleet is currently limited to 224 vessels, the significant effects already witnessed are concerning for Montenegrin bottlenose dolphins. To develop in‐situ mitigation strategies, there is a clear need to better understand the impact that fisheries interactions have on these individuals. [ABSTRACT FROM AUTHOR]

Abstract Background Many species of sharks, including the dusky shark Carcharhinus obscurus, are often incidentally captured in commercial pelagic and bottom longline fisheries. Incidental capture can lead to at-vessel or post-release mortality and can be detrimental to populations of threatened, endangered, or prohibited species. The estimated at-vessel mortality for dusky sharks can be high in longline fisheries and, to minimize mortality, time–area closures have been designated in the western North Atlantic Ocean to mitigate interactions with longline fisheries, yet incidental capture of dusky sharks is still common. We compared the vertical and horizontal movements of dusky sharks to the overall fishing effort and depth fished of commercial pelagic and bottom longline fisheries to determine when and where overlap is present that could lead to incidental capture. Results Twenty-one (n = 21) dusky sharks were tagged with pop-up archival transmitting satellite tags and all were immature animals (123–200 cm FL) apart from two individuals (230 and 300 cm FL). Sharks were tagged off the coasts of North Carolina (71%) and Florida (29%). Twenty tags (95%) reported and provided tracks between 1 and 107 days (median 15 days) and 10 tags (50%) remained on sharks for > 4 days. Most individuals remained within the bottom longline closed area off the coast of North Carolina during their time at liberty. Dusky sharks primarily occupied the 20–40 m depth range 26% of the time, and overlapped with bottom and pelagic longline gears 41% and 59% of the time, respectively. Overlap was highest in the winter and spring for both commercial fisheries. Conclusions The use of archival satellite telemetry in this study has provided valuable preliminary information on vertical and horizontal movements of immature dusky sharks in western North Atlantic Ocean. Dusky sharks may be more vulnerable to incidental capture in the pelagic longline fishery due to the high fishing effort, larger areas of horizontal overlap, and greater percentage of vertical overlap. This information will inform mitigation measures of commercial longline fisheries, which can work toward population rebuilding of the species.

This study will evaluate the efficacy of electronic software programs intended to replace mandatory commercial fishing paper-logbooks. This paper will not address electronic logbooks for recreational fishermen, electronic monitoring software for fishery observers, or programs designed to collect supplemental information from commercial fishermen. This project will provide a report on the status of electronic catch-reporting options in 23 coastal states. It is valuable to understand how state data managers follow different processes to design and launch electronic logbooks. In addition to a status-report on electronic reporting options, this document will identify the six core components of successful electronic logbook projects. To best capture the status of electronic logbook efforts nationwide, 17 interviews with state data managers and electronic logbook developers were conducted. Each state fishery was researched, and data managers were asked to subjectively describe how electronic logbooks contributed to information collection in their state. The study was most interested in obtaining unique regional insight that could identify successful components to guide future electronic logbook projects.  Lastly, training materials and assistance options available to fishermen on each state website were evaluated.

Incidental catch of marine species can create ecological and economic issues, particularly for endangered species. The smalltooth sawfish (Pristis pectinata) is endemic to the Atlantic Ocean and listed as Endangered in the US Endangered Species Act. One of its major threats is bycatch mortality in commercial fisheries.Despite the protection afforded by the US Endangered Species Act, smalltooth sawfish are still captured as bycatch in commercial fisheries. Acoustic and satellite tag data collected on 59 sawfish between 2011 and 2019 were analysed to assess commercial fishery bycatch risk for large juveniles and adults off Florida. This study focused on shrimp trawl, south‐east coastal gillnet, and shark bottom longline fisheries, as these were identified in the recovery plan as having the greatest potential threats to recovery.Bycatch risk associated with the shrimp trawl fishery was significantly higher than the other fisheries, indicating that this fishery currently poses the greatest threat to recovery.Bycatch risk was concentrated in all seasons in the Gulf of Mexico adjacent to the lower Florida Keys for the shrimp trawl fishery, off Cape Canaveral in the south‐east coastal gillnet fishery, and in the Atlantic Ocean adjacent to the Florida Keys in the shark bottom longline fishery.Tagging location and sex were predictors of bycatch risk. Individuals tagged in Charlotte Harbor had the highest shrimp trawl bycatch risk. Females tagged in south Florida tended to reside in the deepest water, which is where shrimp trawl effort is highest. Therefore, females may be at more risk in these deeper waters.Results from this study indicate a year‐round closure of waters off south‐west Florida to the shrimp trawl fishery between Charlotte Harbor and the western Florida Keys would reduce sawfish bycatch, and thus mortality, which is in line with recovery plan goals. [ABSTRACT FROM AUTHOR]

Marine mammal interactions with fisheries, such as bycatch and depredation, are a common occurrence across commercial and small-scale fisheries. We conducted a systematic review to assess the management responses to marine mammal interactions with fisheries. We analyzed literature between 1995 and 2021 to measure research trends in studies on direct and indirect interactions for: (i) high and low to middle-income countries, (ii) fishery operations (commercial and small-scale), and (iii) taxonomic groups. Management responses were categorized using the framework described previously in peer-reviewed studies. Marine mammal bycatch remains a major conservation concern, followed by marine mammal depredation of fishing gear. A high proportion of studies concentrated on commercial fisheries in high-income countries, with an increase in small-scale fisheries in low to middle-income countries between 1999 and 2020. The insufficient understanding of the social dimensions of interactions and the inevitable uncertainties concerning animal and human behaviors are major challenges to effective management. Despite the key role of human behavior and socioeconomics, we found only eight articles that incorporate human dimensions in the management context. Integrating social dimensions of marine mammal interactions with fisheries could help in setting pragmatic conservation priorities based on enhanced understanding of critical knowledge gaps. An area-specific adaptive management framework could be an effective tool in reducing the risk to marine mammals from fisheries by coupling technical solutions with socio-economic and political interventions. We conclude that despite the vast body of literature on this subject, a “silver bullet” management solution to marine mammal interactions with fisheries does not yet exist.

The existence of a commercial fishery in a coastal community is often promoted by the tourism sector as a key feature to encourage visits by tourists. However, the contribution of fisheries to tourism in coastal communities in the economic literature is unclear, with mixed results from previous studies. In this study, we examine the counterfactual—how would tourism change in the absence of fishing, and how would this affect benefits to tourists and the local economy. We use a contingent behavior travel cost model, combining revealed and stated preference data, to estimate these changes for Mooloolaba, a coastal fishing town in the Sunshine Coast region of Queensland, Australia. We find that the fishing industry and related provision of local seafood generate $6 million in welfare gains to visitors. We further estimate that it is directly responsible for 19% of the total number of days visiting the town, contributing an additional $8 million per year through tourism related expenditure. Given the importance of the fishing industry to the tourism sector in coastal communities, there is a need for the tourism industry to engage in the fisheries management process.

Climate change is altering ecosystems and fisheries throughout the world's oceans, demanding climate‐adaptive governance for conserving and managing living marine resources. While in some regions fisheries management systems address wider ecosystem dynamics within management frameworks and decision‐making, which may facilitate resilience to climate change, there remains a shortfall in terms of directly incorporating climate change adaptation into fisheries management legislation and implementation. This review assesses the current state of implementation of climate change adaptation into fisheries management policies and legislation across 11 national case studies, based on government documents and the primary literature. The overarching goal is to understand the key elements and gaps in existing fisheries management policies and legislation in the context of climate change. Given recent reforms of fisheries management policies and/or legislation across the nations examined, political recognition of the need to address climate change adaptation in fisheries management appears to be increasing; albeit formal mandates of climate‐adaptation objectives in fisheries management are largely missing. Based on our review, recommendations for achieving climate‐adaptive fisheries management regimes are developed. Overall, this study will help to inform and broaden the scope of management approaches and tools to accelerate the move towards adaptive fisheries management that accounts for climate change impacts on fish stocks, fisheries and the societies that depend upon them. [ABSTRACT FROM AUTHOR]

Marine ecosystem forecasting is an important innovation in fisheries science with considerable value for industry and management, providing new data‐driven means of predicting the distribution and availability of commercially exploited fish stocks over a range of timescales, including near‐real‐time and seasonal. Marine ecosystem forecasting is rapidly advancing as a field, yet tools produced for fisheries to date focus primarily on predicting species distributions. The next generation of marine ecosystem forecasting products could be enhanced by also incorporating predictions of biological characteristics of fish caught, such as body condition and epidemiological status, thereby expanding the utility of these methods beyond predicting distribution alone. Improving the biological dimensions of marine ecosystem forecasting could allow for optimization of efficiencies in wild‐capture fisheries by minimizing discarding and waste and maximizing the value of landed fish. These advancements are of direct benefit to industry and management, address several of the United Nations Sustainable Development Goals pertaining to fisheries sustainability and have the potential to support the maintenance of global food and micronutrient security under rapidly changing environmental conditions. Here, we describe the current state of the art in marine ecosystem forecasting; review the physical‐biological linkages that underlie variability in the body condition of commercially valuable fish and shellfish with particular reference to marine climate change; and outline key considerations for the next generation of marine ecosystem forecasting tools for wild‐capture fisheries. [ABSTRACT FROM AUTHOR]

Landing data are the most basic information used to manage fisheries, although they are often unavailable or incomplete. The objective of this work was to reconstruct the national database of marine commercial landings for the Brazilian industrial and artisanal fisheries, from 1950 to 2015. Total landings increased strongly from 1950 to mid-1980s and suffered sharp decline in the early 1990s, mainly associated to the collapse of sardine fisheries. After that, another period of increasing landings was observed, but at a much lower rate. Industrial landings always surpassed artisanal landings in Brazilian waters, except for the beginning of the time series, when many industrial fleets had not started yet, and in the early 2000s, when a change in the methodology for collecting landing statistics was implemented in the state of Pará leading to an overestimation of artisanal landings. Artisanal fisheries have been declining since 2005, which is worrisome due to the social impact it may have on local income and food security. Regional differences were also observed, with industrial landings being always higher than artisanal landings in southeastern-southern Brazil, while the opposite was true for the northern-northeastern regions. Higher landings were observed in the southeastern-southern regions when both artisanal and industrial fleets were combined. Sardine and demersal fishes were the main resources landed by industrial fishers. Artisanal fishers caught more species than their industrial counterpart, featuring Xiphopenaeus kroyeri, Cynoscion acoupa, and Ucides cordatus. Although the fishing of Epinephelus itajara was banned in Brazil, it continues to be landed. Yet, catches of this species and others under some threat status are still not properly registered, including: Carcharhinus longimanus, Galeorhinus galeus, Sphyrna lewini, Sphyrna mokarran, Pristis pectinata, and Pseudobatos horkelii. Fishing resources not identified in previous landing reconstruction efforts, such as sea urchins and sea cucumbers, have now been reported. The database presented here should be continuously updated and improved. It is of paramount importance to resume the collection of landing statistics, including information on fishing effort, to assess the relative impact of fisheries and environmental factors on the main Brazilian fishing stocks.

Background: Many species of sharks, including the dusky shark Carcharhinus obscurus, are often incidentally captured in commercial pelagic and bottom longline fisheries. Incidental capture can lead to at-vessel or post-release mortality and can be detrimental to populations of threatened, endangered, or prohibited species. The estimated at-vessel mortality for dusky sharks can be high in longline fisheries and, to minimize mortality, time–area closures have been designated in the western North Atlantic Ocean to mitigate interactions with longline fisheries, yet incidental capture of dusky sharks is still common. We compared the vertical and horizontal movements of dusky sharks to the overall fishing effort and depth fished of commercial pelagic and bottom longline fisheries to determine when and where overlap is present that could lead to incidental capture. Results: Twenty-one (n = 21) dusky sharks were tagged with pop-up archival transmitting satellite tags and all were immature animals (123–200 cm FL) apart from two individuals (230 and 300 cm FL). Sharks were tagged off the coasts of North Carolina (71%) and Florida (29%). Twenty tags (95%) reported and provided tracks between 1 and 107 days (median 15 days) and 10 tags (50%) remained on sharks for > 4 days. Most individuals remained within the bottom longline closed area off the coast of North Carolina during their time at liberty. Dusky sharks primarily occupied the 20–40 m depth range 26% of the time, and overlapped with bottom and pelagic longline gears 41% and 59% of the time, respectively. Overlap was highest in the winter and spring for both commercial fisheries. Conclusions: The use of archival satellite telemetry in this study has provided valuable preliminary information on vertical and horizontal movements of immature dusky sharks in western North Atlantic Ocean. Dusky sharks may be more vulnerable to incidental capture in the pelagic longline fishery due to the high fishing effort, larger areas of horizontal overlap, and greater percentage of vertical overlap. This information will inform mitigation measures of commercial longline fisheries, which can work toward population rebuilding of the species. [ABSTRACT FROM AUTHOR]

The Western Mediterranean fisheries significantly contribute to the regional blue economy, despite evidence of ongoing, widespread overexploitation of stocks. Understanding the spatial distribution and population dynamics of species is crucial for comprehending fisheries dynamics combining local and regional scales, although the underlying processes are often neglected. In this study, we aimed to (i) evaluate the seasonal and long-term spatio-temporal fluctuations of crustacean, cephalopod, and fish populations in the Western Mediterranean, (ii) determine whether these fluctuations are driven by the spatial structure of the fisheries or synchronic species fluctuations, and (iii) compare groupings according to the individual species and life history-based groups. We used dynamic factor analysis to detect underlying patterns in a Landing Per Unit Effort (LPUE) time series (2009–2020) for 23 commercially important species and 33 ports in the Western Mediterranean. To verify the spatial structure of ports and species groupings we investigated the seasonal and long-term spatio-temporal fluctuations and common LPUE trends that exhibit non-homogeneous and species-specific trends, highlighting the importance of life history, environmental and demographic preferences. Long-term trends revealed spatial segregation with a north-south gradient, demonstrating complex population structures of Western Mediterranean resources. Seasonal patterns exhibited a varying spatial aggregation based on species-port combinations. These findings can inform the Common Fishery Policy on gaps challenging their regionalisation objectives in the Mediterranean Sea. We highlight the need for a nuanced and flexible approach and a better understanding of sub-regional processes for effective management and conservation – a current challenge for global fisheries. Our LPUE approach provides insight into population dynamics and changes in regional fisheries, relevant beyond the Mediterranean Sea. • DFA common LPUE trends showed non-homogeneous and species-specific trends. • Long-term trends revealed spatial segregation with a north-south gradient. • Seasonal analysis showed spatial aggregation based on species-port combinations. • CFP in the Mediterranean should consider fisheries dynamics at sub-regional scale. [ABSTRACT FROM AUTHOR]

In Portugal it has been estimated that unreported catches represent one third of total catches. Herein, information on landings and total unreported catches (discards) by commercial métier were disaggregated into high taxonomic detail using published scientific studies. Fish accounted for 93.5% (115493 t) of overall unreported catches per year, followed by cephalopods (2345 t, 1.9%) and crustaceans (1754 t, 1.4%). Sharks accounted for 1.3% of total unreported catches in weight (1638 t/y). Unreported taxa consisted mostly of the commercial landed fish species: Scomber colias, Boops boops, Trachurus picturatus, T. trachurus, Merluccius merluccius, Sardina pilchardus, Liza aurata and Micromesistius poutassou, which together accounted for 70% of the unreported discarded catches. The number of unreported/discarded species was highest in artisanal fisheries, followed by trawl and purse seine. In artisanal fisheries, L. aurata, S. colias, S. pilchardus, Trachinus draco and B. boops accounted for 76.4% of the unreported discards. B. boops, S. colias and S. pilchardus were also among the most discarded purse seine species, together with Belone belone accounting for 79% of the unreported catches. In trawl fisheries, T. picturatus (16%), M. merluccius (13%), S. colias (13%) and M. poutassou (13%) accounted for 55% of the trawl discarded unreported catches. The discarded species that most contribute to overall unreported catches are those that are most frequently landed and that most contribute to overall landings in weight.

Fisheries bycatch of non‐target species in the commercial fleet is a major source of anthropogenic injury and mortality for sea turtles and marine megafauna.The Río de la Plata maritime front (RLPMF) and its adjacent international waters – comprising part of the Argentine and Uruguayan exclusive economic zones, is a highly important fishing ground in the south‐western Atlantic Ocean as well as feeding and development grounds for sea turtles.This paper analyses the distribution of the bottom and pelagic trawling fishery within the RLPMF using information from Vessel Satellite Monitoring System. With this information, areas of highest trawling intensity were defined and further evaluated their overlap with sea turtle habitat‐use areas from available sea turtle satellite tracking information.Results besides identifying high‐susceptibility areas for sea turtle bycatch by the commercial trawler fleet along the RLPMF, provide predictive tools to identify vulnerable areas to interaction of sea turtles and the commercial fishing fleet.Implementation of bycatch mitigation measures, such as reduced fishing effort areas by the Argentine and Uruguayan fisheries management agencies has the potential to benefit the fisheries as well as marine megafauna. Furthermore, there is a need for additional research on the impact that this fleet can have on sea turtles present in the area. [ABSTRACT FROM AUTHOR]

San Diego has had a strong commercial fishery for over a century and was even considered the “tuna capital of the world” during the mid-1900s due to the booming albacore tuna fishery. Restaurants along the waterways advertise fresh, local seafood to the locals and 32 million tourists that annually visit San Diego when in reality, nearly all the seafood being served comes from all over the world and was caught days or months earlier. In this information age, it is time for better communication between all the parties involved from the fisheries to the restaurants and stores to the consumer. To facilitate this communication, it is first necessary to gather information about San Diego’s fishery including identifying the major players and how they do, or do not, communicate with one another. This project collected information through surveys and numerous personal interviews. It was revealed that San Diego faces many challenges in creating a Community Supported Fishery after the model that others have used but may be successful with alternative models.

Fisheries represent the principal economic activity in the Northern Gulf of California, Mexico, but few targeted species are managed by any type of harvest controls. This study assessed the sustainability of two main fisheries in the area: fine-scale triggerfish (Balistes polylepis) and leopard grouper (Mycteroperca rosacea) by comparing estimates of annual landings (fisheries production) with the surplus biomass produced on fishing grounds (biological production) of each species. The specific objective of the study was to determine for each species whether fisheries production exceeds biological production, which would indicate that overfishing is occurring. Results of this comparison show that fishing is more than 3 times higher than surplus production for leopard grouper and 15 times higher than surplus production for triggerfish. These results suggest that both species are in an overfishing state.

Planned adaptation to climate impacts and subsequent vulnerabilities will necessarily interact with autonomous responses enabled within existing fisheries management processes and initiated by the harvest and post-harvest components of fishing industries. Optimal adaptation options are those which enable negative effects to be mitigated and opportunities that arise to be maximized, both in relation to specific climate-driven changes and the broader fisheries system. We developed a two-step participatory approach to evaluating adaption options for key fisheries in the fast-warming hotspot of south-eastern Australia. Four fisheries (southern rock lobster, abalone, snapper, and blue grenadier) were selected as case studies on the basis of their high to moderate vulnerability to climatic effects on species distribution and abundance. Involved stakeholders undertook a “first pass” screening assessment of options, by characterizing and then evaluating options. In the characterization step potential adaptation options for each fishery, contextualized by prior knowledge of each species’ climate change exposure and sensitivity, were described using a characterization matrix. This matrix included: the specific climate vulnerability/challenges, the implications of each option on the fishery system as a whole, the temporal and spatial scales of implementation processes, and realized benefits and costs. In the evaluation step, semi-quantitative evaluation of options was undertaken by stakeholders scoring the anticipated performance of an option against a pre-determined set of criteria relating to perceived feasibility, risk (inclusive of potential costs), and benefit. Reduction of the total annual commercial catch as well as reductions in both effort and catch through spatial and temporal closures were the options scored as having the highest level of expected benefit and of feasibility and the lowest level of risk of negative outcomes overall. Our screening assessment represents a pragmatic approach to evaluate and compare support for and the effects of alternative adaptation options prior to committing to more detailed formal and resource intensive evaluation or implementation.

University of California Sea Grant Extension Program and the California Department of Fish and Game (CDFG) convened a fisheries management workshop December 1-4, 2008, in Berkeley, CA. The workshop, entitled “Managing Data-Poor Fisheries: Case Studies, Models and Solutions,” was designed to provide ideas to CDFG about ways to manage California fisheries when available data are insufficient for single species or ecosystem-based management.

Sperm limitation is a concern for a number of heavily fished decapods; however, work to assess this concern is sometimes hampered by a lack of simple techniques to quantify sperm transferred during reproduction. Our primary goal was to determine if DNA measurements could be used to quantify the sperm content of spermatophores and thus facilitate investigations of sperm limitation in American lobsters (Homarus americanus H. Milne Edwards, 1837). This was achieved by measuring the amount of DNA in a sample and then calibrating those values by using flow cytometry to count the number of individual sperm present in the sample. Our results show that the DNA quantification technique provides a fast and accurate way to quantify sperm. We then demonstrated the utility of the method by using it to examine the rate at which males can produce sperm under simulated conditions of repeated mating events, a situation that might lead to a reduction in the number of sperm per spermatophore. While spermatophores obtained from male lobsters at three-day intervals varied substantially in the number of sperm they contained (range 427,090–5,028,996; mean 2,306,473), there was no clear decline in sperm count over time. These results suggest that male lobsters replenish their sperm supplies rapidly, and that sperm recharge rate is unlikely to be a factor that could lead to sperm limitation in American lobster populations. [ABSTRACT FROM AUTHOR]