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The River Indus is one of the most extended water bodies in Pakistan. It is a source of drinking water, hydroelectric power generation, irrigation, agriculture and aquaculture. The present examination wanted to survey the river's physicochemical parameters and biodiversity from June 2016 to May 2017. Total eight stations have been selected along the Indus River, and 08 water quality parameters, i.e., temperature, salinity, dissolved oxygen, power of hydrogen, transparency, alkalinity, hardness, and total dissolved solids, have been checked from all stations on the spot and bring water samples in a plastic bottle. Fish samples were also collected from all stations, preserved all the samples in 10% formalin, and further investigated in the Fresh Water Biology Laboratory at the University of Sindh Jamshoro. A total of 45 fish species have been identified throughout the study period. [ABSTRACT FROM AUTHOR]

This paper uses a particle tracking model to simulate the distribution of fishing-related marine-sourced plastic litter from demersal trawling activities along the Atlantic coast of Scotland. The modelled fishing litter dispersed widely across the region, with ∼50% of the particles beaching along the northwestern Scottish coast after a year-long simulation. The model was tuned using observations of beached litter loadings along the same coastline to estimate the annual input, by mass, of small (<1 kg) plastic litter. Model results suggest that between 107 g and 280 g of small fishing-related litter enters the ocean per hour of fishing, resulting in an estimated 234 t to 614 t of small fishing-related litter entering the ocean annually on the Scottish west coast. These results suggest that fishing on the Atlantic coast of Scotland may be a significant source of marine plastic. However, more modelled and observational data are required to reduce uncertainty. • Fishing is a significant source of plastic litter on the west coast of Scotland. • A model calibrated by field data is used to predict mass input of fishing litter. • An estimated 107–280 g of small fishing litter enters the ocean per hour of fishing. • Each year, 234–614 t of small fishing litter enters the ocean in western Scotland. • Remote, less-populated coastlines, found higher levels of fishing-related litter. [ABSTRACT FROM AUTHOR]

Data provided by the Southeast Area Monitoring and Assessment Program (SEAMAP) shrimp/groundfish trawl survey have long been used in assessing diverse managed taxa, including several reef fishes; however, there are rising concerns over the impacts of trawling on live‐bottom habitats. Using data collected from summer SEAMAP trawl surveys (2009–2016; N = 1,103), we examined how avoiding areas of live‐bottom habitat might affect the survey's ability to assess interannual changes in abundance of managed reef fish taxa. Trawl samples at 48% of sampling sites contained <50 kg of sponge, and 12% of sampling sites contained at least 50 kg of sponge, while 40% of sites had zero sponge bycatch. Mean number of taxa, taxonomic richness, and taxonomic diversity were significantly higher as sponge bycatch increased, while the total number of individuals remained the same. To examine interannual variability of managed reef fish taxa, annual indices of relative abundance were calculated on different subsets of data (all data, data excluding sites with sponge bycatch ≥50 kg, and data excluding all sites with sponge bycatch). For Red Snapper Lutjanus campechanus and pink shrimp Farfantepenaeus duorarum, indices and general trends were largely unaffected by excluding sites with sponge, but for most selected taxa (e.g., Gray Triggerfish Balistes capriscus and Red Grouper Epinephelus morio), overall trends were affected by excluding sites that contained sponge bycatch, and in some cases the frequency of occurrence did not meet the requirement to calculate an index of abundance (i.e., <5%) when sponge sites were excluded (e.g., Hogfish Lachnolaimus maximus). Efforts to mitigate survey interactions with live‐bottom habitats will likely alter the utility of survey data and the ability to assess managed species, so careful consideration is needed to evaluate any trade‐offs between the benefits of the trawl survey for fishery assessments and the benefits of protecting the habitat. [ABSTRACT FROM AUTHOR]

The labrid fish species Oxycheilinus arenatus (Valenciennes, 1840) is recorded for the first time from India's southeast coast. A total of three specimens were collected as trawl bycatch at Tuticorin, Tamil Nadu, southeast coast of India, in December 2021. The standard length of the specimens ranged from 15.42 to 19.5 cm SL. The presently reported finding of this species from the southeastern coast of India expands and confirms the known distribution range of O. arenatus, which was previously not known from India. [ABSTRACT FROM AUTHOR]

Adaptive spatial management provides a way to balance the conservation of bycatch species and the potential economic effects of bycatch‐induced closures on a fishery, but implementation can be both data and resource intensive. We present a survey exploring a novel approach to adaptively manage an intermittent bycatch issue in an inshore trawl fishery where Sciaenidae bycatch species (including juvenile Mulloway Argyrosomus japonicus, a species of conservation concern) co‐occur with large aggregations of a valuable target species (eastern school prawn Metapenaeus macleayi), following flood‐induced egression from estuarine habitats. Diurnal sampling surveys followed three flood events and targeted permanent inshore closure zones (designed to protect the normally nocturnally harvested eastern king prawn Melicertus plebejus) and adjacent inshore nonclosure areas. Sciaenidae abundance was mostly <10 fish/ha trawled, but larger catches generally corresponded with larger catches of eastern school prawn, and these relationships appeared to be steeper within nonclosure zones. There were only minor differences in the size structure of eastern school prawn between zones, and patterns were event and location specific. Negligible eastern king prawn were encountered. The results show that temporarily allowing fishers access to permanent trawl closures following floods may support the exploitation of aggregated target species with reduced interaction with bycatch species of concern. The approach presented here is relevant to the consideration of adaptive spatial management in other trawl fisheries. [ABSTRACT FROM AUTHOR]

Reducing the impacts of bottom trawling on seafloor habitats is a management priority in the U.S. West Coast groundfish bottom trawl fishery as well as other trawl fisheries internationally. Modifications to conventional bottom trawls, such as semi-pelagic trawl technology, are commonly used in demersal fisheries to reduce trawl-seafloor interactions by elevating the doors and portions of the sweeps off the seafloor. This study evaluated changes in catch efficiency and trawl geometry between a conventional bottom trawl outfitted with bottom-tending doors and the same trawl modified with midwater doors to fish semi-pelagically. We observed the seafloor interactions using Dual-frequency IDentification SONar (DIDSON) and quantified the reduction in trawl-seafloor interactions by periodically placing an altimeter on the semi-pelagic trawl door to measure height off bottom. Across the tows where the altimeter was used, results showed that the midwater doors fished off bottom >96% of all tow durations at a minimum height of 0.6 m. The midwater doors also spread 43 m wider on average than the conventional doors, which was significant (p < 0.001). Catch comparison results showed no significant difference in catch efficiency between the two gear types for any target groundfish species, however, the mean catch per unit effort for sablefish (Anoplopoma fimbria) did substantially increase when switching from the conventional to semi-pelagic trawl. Mean door spread did not significantly affect the catch efficiency of any species. DIDSON and altimeter data showed the midwater doors and raised sweeps provide clearance for low profile and infaunal benthic organisms to pass beneath without contact. This study demonstrates semi-pelagic trawl gear can effectively harvest demersal groundfishes in this fishery while substantially reducing trawl interactions with the seafloor. While our study has direct management implications for the U.S. West Coast groundfish bottom trawl fishery, our findings are also likely to apply to other demersal trawl fisheries internationally where reducing the impacts of bottom trawling on seafloor habitats is a management priority. • Developed a semi-pelagic trawl with off-bottom doors for harvesting demersal fishes. • The doors of the semi-pelagic trawl fished off bottom >96% of all tow durations. • DIDSON imaging sonar was used to examine trawl-seafloor interactions. • Results show the semi-pelagic trawl can effectively harvest demersal groundfishes. • Trawl-seafloor interactions can be considerably reduced using a semi-pelagic trawl. [ABSTRACT FROM AUTHOR]

The historiography of British distant-water fishing concentrates on the period prior to 1976 and the third 'Cod War' that saw British trawlers excluded from their principal fishing grounds. Little research has hitherto been done on the period afterwards, during which the industry was obliged to prosecute a variety of fisheries, mostly in home waters, on a seasonal basis. This article partially fills that gap by examining its participation in the coastal mackerel fishery, which during the late 1970s and early 1980s offered the most promising opportunity to keep the fleet employed. However, it forced upon trawler firms a different pattern of operations and required participation for the first time in the burgeoning international market for fish. Despite the difficulties of adapting to this new form of fishing, the mackerel fishery kept the distant-water fleet in business until overfishing, tightening restrictions on catches and the finalisation of the Common Fisheries Policy drove a further wave of contraction in the industry during the early 1980s. [ABSTRACT FROM AUTHOR]

Although spatially explicit decision support tools are widely used in marine conservation planning, only a few studies have used multi-objective approaches to explicitly achieve biodiversity conservation and sustainable use objectives. Here, we use spatial analyses of a comprehensive environment-based classification (developed using Gradient Forest modelling) that summarises spatial patterns in demersal fish composition and turnover in the oceans around New Zealand, and a 20-year record of trawl locations (representing spatial use by fishers), to identify options for biodiversity protection that vary in their relative delivery of conservation outcomes and impacts on fishers. We also compare analyses carried out at a national scale with those generated by aggregating independent regional analyses. The top-ranked 20% of sites identified using fish composition data alone would on average protect 33% of the geographic range of each fish species, but would result in a 58% loss of areas currently fished. By contrast, using the trawl locations as a cost layer reduced average fish protection by 23% in relative terms, but loss of fished areas was almost eliminated. Using different weightings to vary the influence of the trawl footprint, a range of intermediate scenarios were identified that delivered greater fish protection than the fully cost-constrained scenario. However, these intermediate scenarios resulted in greater reductions in the area retained for fishers than the biodiversity optimised scenario. Aggregated regional scenarios delivered lower conservation returns and higher impacts on fisheries than comparable single national scenarios, reflecting the constraining of opportunities for biodiversity protection whilst avoiding overlaps with trawling. While stakeholder MPA design processes often occur at regional scales, our analyses demonstrate the value of considering both regional and national analyses to identify optimal reserve configurations. • Spatial estimates of demersal fish composition and turnover, and trawl fisheries were used to identify options for biodiversity protection. • The analyses were carried out at both national and regional scales. • Exploration of scenarios ranged from complete protection of economic resource use through to maximising the protection of biodiversity. • Regional scenarios delivered lower conservation returns and higher impacts on fisheries than comparable single national scenarios. [ABSTRACT FROM AUTHOR]

Demersal fishing operations exert, cumulatively, at least three forms of pressures over the benthic environment: mortality of megafauna (landed and discarded), discards of carrion back to the marine environment (also referred to as Predictable Anthropogenic Food Subsidies - PAFS) and disturbance of the seabed, by contact with bottom gear. This study presents a spatial synthesis of these forms of pressure on the Brazilian Meridional Margin (BMM, SW Atlantic) and their accumulated effect, in contribution to the development of effective space-based fishing management strategies. We analyzed landed catch, discards and effort of 2,125 fishing trips of industrial vessels operating double-rig trawlers, pair trawlers, stern trawlers, bottom longline and gillnets, monitored during 2018 in the main fishing harbors of Southern and Southeastern Brazil. All forms of pressure and the Accumulated Pressure Index (API) were represented spatially in a 20 × 20 nautical mile quads mesh grid. We demonstrated that nearly half of the BMM area was under high pressure. We also delimited fishing pressure hotspots in coastal and shelf areas mostly within the 'Brazilian Bight' region, between São Paulo and Santa Catarina states (24–29°S). Conversely, slope regions were found to be less demanded by demersal fishing, with both benthic ecosystems and demersal populations being barely disturbed. These were regarded as the main refuge areas for benthic and benthopelagic megafauna. Double-rig trawling was a major driver of pressure accumulating over half of total number of demersal fishing trips in 2018. Individual double-rig trawling operations also disturbed a seabed area far greater than the areas disturbed by the other fishing gear, and discarded the largest fraction (∼48%) of the produced mortality. Reducing the demersal fishing pressure on the BMM seems to be primarily concerned with abating the intensity of double-rig trawling, and/or diluting their effect through spatial management measures. • Nearly half of the Brazilian Meridional Margin area was under high pressure. • Hotspots were on the coastal and shelf areas between 24°S and 29°S. • Refuges extended along most shelf break and slope areas. • Double-rig trawl was a major driver of cumulative pressure. [ABSTRACT FROM AUTHOR]

The effective implementation of the Marine Strategy Framework Directive (MSFD) and formulation of spatial management policies rely heavily on a good understanding of the extent, distribution and intensity of human pressures and their overlap with benthic habitats. However, little research has quantified the pressure and impact on the seabed of bottom contact gears other than trawling. This study analyzes the spatio-temporal trends of fishing pressure of bottom-contact gear, including mobile and static gears, and asseses its relative importance within each benthic habitat. To achieve this, a set of pressure indicators was calculated using vessel monitoring system information from the Bay of Biscay for 2009–2020. Nested General Linear Models were conducted to assess the temporal fluctuation of fishing activities. While trawlers exhibited wider and higher levels of fishing intensity over sedimentary habitats, set gillnet and set longliners were distributed among more sensitive habitats, such as biogenic reef habitats. Additionally, there was a significant decrease in fishing effort in recent years along Offshore circalittoral habitats, particularly with respect bottom trawling, in contrast to increasing fishing intensity in deeper areas. These results emphasize that from a conservation perspective and MSFD implementation, there is a need to quantitatively analyze the fishing footprint of all fishing gears, including static gears in the regional assessments, and the necessity to progress in adapting impact indicators to these fishing activities. The findings are discussed based on the potential impacts of policies such as the MSFD and can assist managers in developing spatial protection measures. [ABSTRACT FROM AUTHOR]

Monitoring marine resource exploitation is a key activity in fisheries science and biodiversity conservation. Since research surveys are time consuming and costly, fishery‐dependent data (i.e., derived directly from fishing vessels) are increasingly credited with a key role in expanding the reach of ocean monitoring. Fishing vessels may be seen as widely ranging data‐collecting platforms, which could act as a fleet of sentinels for monitoring marine life, in particular exploited stocks. Here, we investigate the possibility of assessing catch composition of single hauls carried out by trawlers by applying DNA metabarcoding to the dense water draining from fishing nets just after the end of hauling operations (hereafter "slush"). We assess the performance of this approach in portraying β‐diversity and examining the quantitative relationship between species abundances in the catch and DNA amount in the slush (read counts generated by amplicon sequencing). We demonstrate that the assemblages identified using DNA in the slush satisfactorily mirror those returned by visual inspection of net content (about 71% of species and 86% of families of fish) and detect a strong relationship between read counts and species abundances in the catch. We therefore argue that this approach could be upscaled to serve as a powerful source of information on the structure of demersal assemblages and the impact of fisheries. [ABSTRACT FROM AUTHOR]

After 42 years of stocking in Lake Champlain, recruitment of wild juvenile lake trout (Salvelinus namaycush) was first observed in 2015. Abundance of wild lake trout juveniles was spatially heterogeneous. Recruitment of wild fish to age-1 and subsequent survival are likely related to growth including overwinter growth. We hypothesized that growth potential or growth-related mortality of wild and stocked fish may explain spatial differences in abundance. We collected juvenile (age-0 to 3) lake trout by bottom trawling in the central, north, and south Main Lake every 2–4 weeks during the ice-free season, 2015–2018. The percentage of wild juveniles increased from 27.8% of the total catch in 2015 to 65.7% in 2018. Rates of growth in length and change in condition were compared in wild versus stocked lake trout, among sampling areas, and between seasons (sampling season relative to winter). Wild juveniles grew equally or faster in length than stocked juveniles at the same age, but changed more slowly in condition. There was a higher percentage of wild juveniles in the central sampling area than the north and south, but no differences in growth among sampling areas. Wild and stocked fish grew in length over winter, but most cohorts (6 of 7) maintained or increased condition. Results indicate high growth potential of wild juvenile lake trout and progress toward population restoration. [ABSTRACT FROM AUTHOR]

The present paper reports the first record of the narrowbar reefgoby, Priolepis profunda (Weber, 1909) from the Indian coast. Two specimens (33.5 and 38.5 mm of TL), were caught during a demersal trawling survey conducted in the area between 9°40.7′N, 76°05.8′E and 9°45.1′N, 76°03.9′E at 33 m in June 2017. The specimens were collected from a coral rock which entered in the trawl net during the demersal resources survey. The morphological descriptions of the specimens collected are compared with those of existing records. [ABSTRACT FROM AUTHOR]

Otter trawls are commonly used in fisheries for benthic fishes, and they provide a source of food to many marine birds. This study aimed to quantify the response of birds, by species, attracted to forage at fishing vessels in Ribeira Bay, Angra dos Reis, Rio de Janeiro, Brazil. Sampling was conducted every two months in 2006 at five stations, for a total of 30 trawls; fish were collected for 20 minutes per trawl. Bird counts were recorded just before the trawling started, when it began, 10 minutes after trawling began, and 10 minutes after it stopped. After trawling, 10 fresh dead fish were released into the water, and we recorded the number of successful and unsuccessful attacks. Our 224 observations included eight bird species; three species--Magnificent Frigatebird Fregata magnificens, Neotropic Cormorant Phalacrocorax brasilianus, and Great Egret Ardea alba--accounted for 68.3%, 10.7%, and 5.8% of the records, respectively. Scoring highest in a Frequency of Occurrence Index were the Magnificant Frigatebird, South American Tern Sterna hirundinacea, and Brown Booby Sula leucogaster, with 75%, 30%, and 25%, respectively. When trawling started, 21% of the eventually recorded birds approached the boat, but after 10 minutes, they dispersed. After trawling stopped, 77% of the eventually recorded birds approached. Most attacks on discarded fish were performed by frigatebirds (79%), which were also the most efficient in getting fish (83%). Our results emphasize the important association of frigatebirds with trawling, in accord with its kleptoparasitic mode of foraging. [ABSTRACT FROM AUTHOR]

The White Fish Authority was the government development body for most of the British fishing industry from its establishment in 1951 until its merger with the Herring Industry Board thirty years later. Setting the WFA in the context of wider debates over the efficacy of development councils in general, this article surveys and critiques the record of the Authority. It argues that despite weaknesses in its conception, financing and management, the Authority was nevertheless a positive force overall. [ABSTRACT FROM AUTHOR]

Trawling is generally an unselective fishing method that is employed to harvest a number of species. Capture of nontarget species that are subsequently discarded is an important issue for trawl fisheries, especially penaeid trawl fisheries. While gear modifications are a common approach to manage this issue, maintaining areas that are closed to trawling may also have a positive impact on these nontarget species. This study systematically examined the diversity and abundance of nontarget species across a network of areas closed to trawling (trawl closure areas) relative to adjacent areas that were open to trawling. Analysis of nontarget species from 209 trawls and 72,787 animals (across 216 taxa) revealed some impact on both abundance and diversity within trawl closure areas. Latitude was a key variable that was driving differences in the taxonomic assemblage among locations. Within locations, there were inconsistent impacts for different nontarget species in trawl closure areas. Length distributions showed size truncation of abundant nontarget species in fished areas relative to adjacent trawl closure areas. While the impact of trawl closure areas varied among species, it was clear that the spatial management in the fishery provided some refuge for a diversity of nontarget species, observed in patterns of species richness, abundance, and population size structure. Latitudinal breadth appears to be an essential component of the trawl closure network, but localized effects may be important for maintaining reproductive capacity for nontarget species. These data highlight the broader utility of trawl closure networks as a management tool for trawl fisheries. [ABSTRACT FROM AUTHOR]

An artisanal shrimp trawl fishery operating illegally in northern Peru has high levels of bycatch and three main commercial species. Here we provide the first characterisation of the socio-economic contribution of this fishery. Estimates have been generated for the capital values, operational and maintenance costs, as well as net profits at point of landing and across the value chain. This fleet sector in northern Peru is estimated at 105 vessels, generating an annual gross income of U$D 4.8 million with 315 direct jobs. Vessel owners could potentially have a net income of over ∼$12,000 per year, and crew are likely to be earning 45 % above the living wage for similar land-based rural employment, including other fishing activities operating in the same areas. With an appropriate multiplier for the seafood supply chain, the gross economic value of the fishery from landings up to the retail level is estimated at U$D 35 million with 915 jobs. Recommendations for improving the sustainability of the fishery and possible mitigations are discussed to address the gulf between policy and regulatory intent and reality, where enforcement is lacking or absent. [ABSTRACT FROM AUTHOR]

Fishing has been practiced in Egypt for several millennia in the Nile and various lakes, the Mediterranean, and the Red Sea. Here, the marine fisheries catch from the area corresponding to Egypt's current Exclusive Economic Zone in the Mediterranean were re-estimated for the shorter period from 1920 to 2019. This study covers reported and formerly unreported commercial and non-commercial, small- and large-scale fisheries catches and estimated discards. Given that the Food and Agriculture Organization (FAO) has been publishing annual fisheries statistics only since 1950, the comparison of reconstructed marine catch data to the FAO-reported catch data covers only the period from 1950 to 2019. Reconstructed marine fisheries catches for the Egyptian Mediterranean EEZ for 1950–2019 were about 1.3 times the reported catch by the FAO on behalf of Egypt. This discrepancy is due to a combination of elements, mainly unreported commercial industrial and artisanal catches and industrial discards. Several events have drastically affected the Mediterranean marine fisheries of Egypt, such as the opening of the Suez Canal, the Aswan High Dam, and, more recently, the Egyptian Revolution of 2011. Climate change has also influenced the overall productivity as well as the species composition of the catch. The Mean Temperature of Catch (MTC) from the Mediterranean Egyptian waters has increased by an annual average of 0.07 °C per year since 1987. The Marine Trophic Index (MTI) showed that 'fishing down' has occurred in Egypt's Mediterranean waters since the early 1970s. The dataset provided by this study can be applied to catch-based indicators to better assess the Egyptian Mediterranean fish stocks. This would help improve fisheries management in the region and ensure the sustainability of the Egyptian Mediterranean fisheries. [ABSTRACT FROM AUTHOR]

This work focuses on the dynamics and retention of microplastics (MP) in the Mediterranean. MP manta-net trawls were performed in autumn 2019 north of the Balearic Islands and along the Balearic Front (BF). Lagrangian modelling was used to find the MP collected origin during the campaign. These combined results show that North of Mallorca is a temporary retention zone of 3 months variability, with MP origin being the Northern Current (NC) and the Gulf of Lion (GOL). Retention processes were less clear along the BF, due to frontal dynamics together with the strong northerly winds. However, it appears that the origin can differ between the North (i.e. the large North-Westerly basin, including the GOL and the NC path) and the South (short distances around the zone) of this front. In both areas, the wind and the current variability are strongly conditioning the existence and position of the MP concentration zones. • Floating Micro-plastics origins inferred in the Mediterranean basin. • Sea campaign performed along the Balearic front and north of Balearic Islands. • Massive inter-annual Lagrangian experiments performed. • Tracking back in time revealed highly variable origins. • North of Balearic Islands are more efficient for accumulation than Balearic front. [ABSTRACT FROM AUTHOR]

Abstract In the 2000s, the Dutch beam trawl fleet was in chronic deficit and under pressure to reduce its environmental impact. Instead of converting to selective fishing gears, it successfully lobbied the European Commission with the support of public authorities and scientists to obtain derogations against formal scientific advice to practice a prohibited technique: electric trawling. Since then, electric trawling has expanded beyond regulatory threshold: 84 large trawlers now catch the vast majority of the Dutch flatfish quota, causing detrimental socio-environmental impacts. To assess whether the European Union's fisheries policies fulfilled legal objectives and implemented the 2030 Agenda, it appeared crucial to quantify how much public financial aid had been provided to the Dutch fishing sector for its conversion to electric trawling. The financial information enabling this evaluation was first concealed but was eventually obtained. We show that the institutional opacity surrounding electric trawling was not serendipitous and has served to dissimulate allocations of public monies to a prohibited fishing method (otter trawl), illegal licenses, and falsely 'scientific' fishing. In breach of EU laws, 20.8 million EUR of structural funds have so far been granted to this sector in the form of direct subsidies, i.e. over 30 times the amount acknowledged by the fishing industry. The findings presented here lift part of the veil surrounding electric trawling, but the complete reconstruction of the impacts of this fishing method can only be done when decision-makers and scientists disclose all data in full transparency and become the warrants of the public interest. Highlights • The Dutch government has concealed data pertaining to public fisheries subsidies. • In breach of EU laws, public subsidies have supported the electric trawling sector. • 20.8 million EUR in direct subsidies have been granted to this sector since 2007. • 2.7 million EUR were used to develop the explicitly prohibited electric otter trawl. • Illegal licenses and falsely 'scientific' fishing were also publicly funded. [ABSTRACT FROM AUTHOR]

Silver Carp Hypophthalmichthys molitrix are elusive fish that can be difficult to capture with conventional management tools. New tools must be developed to help increase the capture of Silver Carp, thereby improving the understanding and management of the species. An electrified dozer trawl was developed in an attempt to increase the capture of Silver Carp while reducing the amount of sampling effort needed to successfully assess a population and inform management actions. We compared Silver Carp catch rates, sample run time, and Silver Carp length frequency distributions from the electrified dozer trawl with those from conventional boat electrofishing. Silver Carp capture was greater and sample time was shorter for the electrified dozer trawl compared to conventional boat electrofishing. Length frequency distributions were similar between gears. The electrified dozer trawl can shorten sample run times and potentially improve Silver Carp capture, thus facilitating management. Use of the electrified dozer trawl should be expanded beyond Missouri River tributaries to further understand the gear's potential for sampling Silver Carp in a diverse array of environments. [ABSTRACT FROM AUTHOR]

Abstract Many states attempt to increase the economic benefits generated from their fish resources through foreign fishing arrangements that can be characterized as trades in fishing services. This paper provides a first assessment of the net economic benefits in a static analysis from one of the oldest such arrangements in West Africa: the coastal bottom trawl fishery. Focusing on the coastal states of Guinea-Bissau, Guinea, Sierra Leone and Liberia, the total resource rent (RR) generated by foreign fishing in 2015 was estimated and then decomposed for the two participants in the trade: the coastal states (RR CS) and the foreign companies (RR FC). The estimated RRs in Liberia and Sierra Leone were negative, with foreign companies assumed to absorb the costs and the coastal states receiving relatively small license fees (equivalent to 5% and 8% of the total revenues from the fishery respectively). In Guinea-Bissau the lower bound of estimated RR was negative, but the country generated significant economic benefits due largely to the annual payment from the European Union under the foreign fishing access agreement. In Guinea significant RRs were estimated, though the country only retained between 2% and 3%. These estimates are subject to data limitations, and given suspected under-reporting of catch and overestimates of fixed costs, are likely underestimated in some cases. The implications from this review are that significant trades are occurring and even increasing without the minimum data required for West African coastal states to adequately evaluate the terms of trade, nor their sustainability. [ABSTRACT FROM AUTHOR]

Widespread bottom trawling in British waters has traditionally been dated from the last decades of the 18th century, and its early heartland has most commonly been identified as the Torbay area of Devon. This article shows that, in fact, by the time Torbay became known as a centre for the industry, bottom trawling was already well-known and relatively widespread around much of England and Wales, as well as large parts of Eastern and Southern Ireland. Following on from an earlier contribution in this journal, it also demonstrates that bottom trawling’s unbroken history, going back to at least the first decades of the 17th century, has always been beset by controversy, but that the middle decades of the 19th century saw a sea-change in official attitudes that, in effect, ushered in an era of unfettered expansion in industrial beam trawling by the 1890s. [ABSTRACT FROM AUTHOR]

Abstract The measurement of total catch on-board a fishing vessel is generally a very complex process, especially to scientific observers. In this context, hauls of large volume, intricate fishing operations and limited access to the capture increase this problem. In this paper, we propose a methodology to address the estimation of catch volume in codends of a crustacean fishery through LiDAR (light and radar) technology. A sensor was used to acquire a three-dimensional representation of an object located at a fixed distance from the device, thereby simulating a fishing codend. Then, a convex-hull algorithm was applied to this representation to obtain an estimation of its volume. Additionally, to obtain further insights, an experimental laboratory setup was used to emulate the volume estimation of catches on a fishing vessel. The dataset acquired by the system was subsequently analyzed to study the percentage errors associated with the estimation process and to test whether the selected variables are significant. The results indicate that there is considerable uncertainty related to the volume estimation, but it can be addressed using a statistical model. This work constitutes the first attempt to provide a methodology to estimate the catch volume of a codend in a Chilean fishery by generating new measurement alternatives for fishery monitoring programs, enforcement and management institutions, as well as the fishing industry. Highlights • A new methodology to estimate catch volume in codends. • The method considers a LiDAR sensor to acquire the 3D information. • A convex-hull algorithm generates volume estimates. • The estimation uncertainty is addressed using a statistical model. • Our method has several advantages with respect to the observers, which is used at present. [ABSTRACT FROM AUTHOR]

Microplastics (MPs) affect both marine and terrestrial biota worldwide for their harmful effects, which range from physical cell damage to physiological deterioration. In this research, microplastics were quantified from gills, liver and muscle of demersal Benguela hakes Merluccius polli (n = 94), caught by commercial trawling from northwest African waters. Plastic polymers were identified using Fourier Transformed-infraRed spectroscopy (FT-iR). Fulton's k condition factor and the degree of DNA degradation in liver were measured. None of the individuals were free of MPs, whose concentration ranged from 0.18 particles/g in muscle to 0.6 in liver. Four hazardous polymers were identified: 2-ethoxyethylmethacrylate, polyester, polyethylene terephthalate, and poly-acrylics. MP concentration in liver was correlated negatively with the condition factor, suggesting physiological damage. Positive association of MP concentration and liver DNA degradation was explained from cell breakage during trawl hauls during decompression, suggesting an additional way of MPs harm in organisms inhabiting at great depth. This is the first report of potential MPs-driven damage in this species; more studies are recommended to understand the impact of MP pollution on demersal species. • Microplastics were counted from gills, liver and muscle in the African hake Merluccius polli. • Microplastics content in liver was negatively associated with hake's condition factor. • DNA degradation in liver suggests additional microplastics damage in demersal species. • Microplastics pollution may threaten fishing resources through poorer fish condition. [ABSTRACT FROM AUTHOR]

Under a discard ban, mixed fisheries must often reduce catches of low-quota species to allow the continuation of fishing activities. This has led to the development of a range of bycatch reduction devices (BRDs) that aim to exploit morphological and behavioral differences among species to facilitate escape of unwanted catch from the fishing gear. However, the exclusion of unwanted species from the catch is often only possible with concomitant losses of other commercial catches. This is the case for the Nephrops (Nephrops norvegicus)-directed mixed demersal trawl fishery, where BRDs aiming at the reduction of catches of cod (Gadus morhua) often lead to considerable losses of other valuable species. In this study, we developed and tested a BRD aimed at exclusively reducing cod catches without affecting catches of Nephrops , flatfish and other roundfish. The design, a bottom escape window, exploits behavioral traits that set cod apart from other species. We collected absolute selectivity data using a paired gears approach and estimated the combined retention of the bottom escape window and a 90 mm diamond mesh codend. The results demonstrated a low total retention of cod (33%) in combination with high retentions of commercial catches of Nephrops (89%), haddock (Melanogrammus aeglefinus) (76%) and plaice (Pleuronectes platessa) (100%), for the populations encountered. This catch profile represents an important and novel achievement for Nephrops -directed mixed demersal fisheries. We compared the performance of this new BRD to one of the most used legal gears in this fishery (the SELTRA 270), demonstrated the new catch profile it can offer to the fishers, and discussed its management implications. • Novel trawl modification resulting in a unique catch profile for a demersal fishery. • Most of the unwanted bycatch of cod (Gadus morhua) was released. • Catches of the target species, Nephrops norvegicus , were not significantly affected. • Catch of commercial bycatch species of round and flatfish was mostly not affected. • Gear development can improve trawl efficiency through selective bycatch reduction. [ABSTRACT FROM AUTHOR]

This article considers the early history of bottom trawling in England. It demonstrates that trawling – and, in particular, beam trawling – has a very long history stretching back to at least the fourteenth century. Over the following two centuries it spread from the Thames Estuary along the south and south-east coasts, and by 1600 its use was widespread and it was being pursued some distance from shore. The article also shows that bottom trawling has always been a controversial practice, and that by the early modern period it was highly unpopular, not only among non-trawling fishermen (who viewed it as a threat to their livelihood), but with many in positions of power who sought to limit and even prohibit its use. Finally, the article considers the contemporary significance of this newly exposed history, given that historical complaints about bottom trawling were framed in remarkably similar terms to those used by its modern opponents. [ABSTRACT FROM AUTHOR]

The Marine Stewardship Council (MSC) certification program in Russia is now well established and, in addition to fishery clients and stakeholders, involves environmental NGOs and experts familiar with the local management system. The present study aims to analyze the current status of the program and constitutes the first study covering all Russian MSC certifications. Based on certification reports and twenty semi-structured interviews with stakeholders, it was shown that problems with certification vary among fisheries. The most advanced in terms of management are the Barents Sea codfish fisheries, which are co-managed by Russia and Norway. The main concern of these fisheries is the use of bottom trawls, which may seriously affect bottom communities. The Alaska pollock fishery in the Sea of Okhotsk experienced serious pressure from rival fisheries during the certification process. In the Far East, interviewees dealing with the salmon fisheries note a high level of illegal, unreported and unregulated (IUU) fishing and insufficient scientific data for comprehensive stock assessment. For small-scale inland perch fisheries from the central part of the country, recreational and illegal fishing are important problems that are difficult to quantify. Many interviewees repeatedly mentioned communication issues, difficulties with access to scientific and management information, and the overall complexity of the MSC certification process. The study shows that important preconditions to expanding certification are making the process manageable for export-oriented companies and developing a national market for sustainable seafood. [ABSTRACT FROM AUTHOR]

Copyright of Marine Pollution Bulletin is the property of Pergamon Press - An Imprint of Elsevier Science and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

The estimated impact of the EU Landing Obligation was investigated, which bans discards of regulated species, in South European fisheries through stakeholders’ perceptions with the intention to identify implementation shortcomings and practicalities that might lead to obstacles to enforcement. Structured interviews were conducted with 173 fishers in 4 countries practicing 4 generic fisheries (as typified by the dominant fishing gear) asking a total of 26 questions. Results show that fishers estimate that the full implementation of the discards ban will result in longer sorting times. Added to the limited space on board, especially in the more productive trawl and purse seine vessels, this may lead to practical difficulties in relation to compliance. Most of the respondents estimate that there are no realistic possibilities of utilizing the formerly discarded fish in the short term, because of the lack of adequate infrastructure on land Furthermore, the possible utilization types foreseen in the regulation will not help offset the costs of bringing former discards to land. The outcomes of this study have confirmed the implementation difficulties of the landing obligation, especially when the fishing industry cannot expect any medium to long-term benefits. [ABSTRACT FROM AUTHOR]

Litter is present in all marine waters around the globe. It consists of several compound classes of which plastic is of special interest because of its high abundance and possible threat to marine organisms. The regional distribution, composition and abundance of large litter items (LI) at the sea floor of the North Sea and the Baltic Sea were investigated based on 175 bottom trawls between 2013 and 2015. Different types of marine litter > 2.5 cm were classified according to the protocol of the ICES International Bottom Trawl Survey. The results showed considerable geographical variation: In the North Sea, a mean litter abundance of 16.8 LI/km 2 was found, whereas the litter abundance in the Baltic Sea was significantly lower (5.07 LI/km 2 ). In general, plastic represented 80% of the litter items. During the study, some methodical aspects with possible impact on the results were identified that need to be addressed in future sampling campaigns. [ABSTRACT FROM AUTHOR]

Lake trout were extirpated from Lake Champlain by 1900, and are currently the focus of intensive efforts to restore a self-sustaining population. Stocking of yearling lake trout since 1972 has re-established adult populations, spawning occurs at multiple sites lake-wide, and fry production at several sites is very high. However, little to no recruitment past age-0 has occurred, as evidenced by the absence of adults without hatchery fin clips in fall assessments; no regular sampling for juveniles is conducted. We began focused sampling for juvenile lake trout in fall, 2015, in the Main Lake using bottom trawling, and expanded sampling to sites in the north and south of the lake in 2016. In 2015 we collected 303 lake trout < 350 mm total length, of which 23.8% were unclipped. Based on non-overlapping length modes, these wild fish comprised at least three age classes (young-of-year, age-1, and age-2). In 2016, we collected 1215 lake trout < 350 mm, including a fourth wild year class (2016 young-of-year). Forty-nine percent of juvenile lake trout from the Main Lake were unclipped; however, only 20% from the north lake and 9% from the south lake were unclipped. The absence of older unclipped fish indicates that recruitment of wild fish began recently. We discuss several hypotheses to explain this sudden, substantial recruitment success, and factors that may be affecting lake trout restoration in Lake Champlain and the Great Lakes. [ABSTRACT FROM AUTHOR]

Abstract: Electrotrawling using electric pulse stimulation is a promising alternative to beam trawling in the brown shrimp Crangon crangon and Dover Sole Solea solea (also known as Solea vulgaris) fisheries of the North Sea. In the sole fishery, a 40–80‐Hz pulse stimulation induces tetany in the muscles, which may result in injuries. Whereas no injuries have been reported in flatfish or selachian sharks and rays, electrically induced spinal injuries have been observed in gadoids such as Atlantic Cod Gadus morhua and Whiting (also known as European Whiting) Merlangius merlangus. This may indicate that fish species with a fusiform shape are more susceptible to electric pulses. Similar variation among species in electrically induced spinal injuries has been observed in freshwater electrofishing, although large variability in vulnerability has been reported among different freshwater fusiform species. Therefore, we aimed to assess the vulnerability of another, nongadoid, fusiform osteichthyan: Sea Bass Dicentrarchus labrax (also known as European Bass Morone labrax). Two length groups of Sea Bass (31.3 ± 2.2 and 42.1 ± 2.5 cm) were exposed to electric pulses as used in commercial electrotrawls targeting Sole (80 bipolar pulses per second, 2% duty cycle). Thereafter, the fish were monitored daily and then euthanized 14 d after exposure for gross, radiographic, and histologic examination. No injuries were found in fish exposed to the electrical pulses. Differences in vertebral morphology among fusiform species may result in varying vulnerabilities to electrically induced spinal injuries. As a result, electrically induced spinal injuries and/or their variability in both marine and freshwater species may be determined by similar morphological parameters. [ABSTRACT FROM AUTHOR]

The molluscan assemblages in a sediment core from the north-eastern Adriatic show significant compositional changes over the past 10,000 yrs related to (1) natural deepening driven by the post-glacial sea-level rise, (2) increasing abundance of skeletal sand and gravel, and (3) anthropogenic impacts. The transgressive phase (10,000–6000 BP) is characterized by strongly time-averaged communities dominated by infaunal bivalves. During the early highstand (6000–4000 BP), the abundance of epifaunal filter feeders and grazers increases, and gastropods become more important. Epifaunal dominance culminates during the late highstand (4000–2000 BP) with the development of extensive shell beds formed by large-sized Arca noae and Ostrea sp. bivalves. This community persists until the early 20th century, when it falls victim to multiple anthropogenic impacts, mainly bottom trawling, and is substituted by an infauna-dominated community indicative of instability, disturbance and organic enrichment. The re-establishment of this unique shell-bed ecosystem can be a goal for restoration efforts. [ABSTRACT FROM AUTHOR]

The aim of this paper is to highlight the productivity of Italian trawl fishery, one of the most important sector in the Italian fishing fleet. As shown in this study, three variables play a significant effect on Total Factor Productivity (TFP) in a given year: the actual number of fishing days, the average market prices of commercial species and the stock of physical capital. While the number of fishing days can have a negative impact on the TFP, a positive correlation occurs instead with the other two variables. It is also possible to observe a high variability in TFP among different regions of Italy, a finding that is to be expected given the dual nature of the Italian economy, characterized by a high level of discrepancy in prosperity between the North and the South. This lends support to the hypothesis that significant positive externalities may occur in a more dynamic business environment, one which is both open to innovation and increased international and social relations. [ABSTRACT FROM AUTHOR]

Systematic seafloor surveys are a highly desirable method of marine litter monitoring, but the high costs involved in seafloor sampling are not a trivial handicap. In the present work, we explore the opportunity provided by the artisanal trawling fisheries to obtain systematic data on marine litter in the Gulf of Cadiz between 2019 and 2021. We find that plastic was the most frequent material, with a prevalence of single-use and fishing-related items. Litter densities decreased with increasing distance to shore with a seasonal migration of the main litter hotspots. During pre-lockdown and post-lockdown stages derived from COVID-19, marine litter density decreased by 65 %, likely related to the decline in tourism and outdoor recreational activities. A continuous collaboration of 33 % of the local fleet would imply a removal of hundreds of thousands of items each year. The artisanal trawl fishing sector can play a unique role of monitoring marine litter on the seabed. • Bottom-trawl fisheries can play a unique role on marine litter monitoring. • Limitation of activities due to COVID-19 lockdown might decrease marine litter. • Litter pollution in the seafloor of the Gulf of Cadiz related to mix sources. • Collaboration with artisanal fishermen key to mitigate seafloor litter. [ABSTRACT FROM AUTHOR]

Fish discards represent a large share of harvested biomass in shrimp fisheries. The aim of this paper is to propose a methodology for valuing discards of both commercial and non-commercial fish species discarded in the Gulf of California shrimp fishery, by estimating the monetary value of forgone fish biomass. The value of commercial fish species was carried out by using growth and population models, in order to simulate the biomass that, if left in the ocean instead of being harvested at Age 0, could reach an optimal fishing size. Using deflated ex-vessel prices, the present value of commercial species hypothetically harvested at an optimal age, was computed. The value of non-commercial fish species represented the forgone benefits of not using discarded biomass for producing fishmeal. Hence, the estimated value of fish diversity discarded in trawling operations in 2013 would range between USD 60.80 million and USD 103.4 million. This estimate is one of the first attempts to give an economic value to both commercial and non-commercial discarded fish biomass. Hopefully, the methodology here proposed will serve as inspiration for further research in economic valuation of marine biodiversity. [ABSTRACT FROM AUTHOR]

We collected plastic debris in the Stockholm Archipelago using a manta trawl, and additionally along a transect in the Baltic Sea from the island of Gotland to Stockholm in a citizen science study. The samples were concentrated by filtration and organic material was digested using hydrogen peroxide. Suspected plastic material was isolated by visual sorting and 59 of these were selected to be characterized with Fourier transform infrared spectroscopy. Polypropylene and polyethylene were the most abundant plastics identified among the samples (53% and 24% respectively). We found nearly ten times higher abundance of plastics near central Stockholm than in offshore areas (4.2 × 10 5 plastics km −2 compared to 4.7 × 10 4 plastics km −2 ). The abundance of plastic debris near Stockholm was similar to urban areas in California, USA, and the overall abundance in the Stockholm Archipelago was similar to plastic abundance reported in the northwestern Mediterranean Sea. [ABSTRACT FROM AUTHOR]

Background. The reticulated dragonet, Callionymus reticulatus, was originally described based on a single specimen, the holotype from Malaga, Spain, south-western Mediterranean, probably collected before 1831. The holotype is now disintegrated; the specific characteristics are no longer discernible. The species was subsequently recorded from several north-eastern Atlantic localities (Western Sahara to central Norway), but missing in the Mediterranean. Material and methods. Specimens of C. reticulatus were observed and collected during two cruises in 2014 and 2016 in the Balearic Islands off Mallorca and Menorca. The collected specimens (8 females) have been deposited in the collection of the Hebrew University of Jerusalem (HUJ). All individuals of C. reticulatus were collected from beam trawl samples carried out during the DRAGONSAL0914 in September 2014, and during the MEDITS_ES05_16 bottom trawl survey in June 2016, on shelf and slope bottoms around the Balearic Islands. Both surveys used a 'Jennings' beam trawl to sample the epi-benthic communities, which was the main objective of the DRAGONSAL0914 and a complementary objective in the MEDITS_ES05_16. The 'Jennings' beam trawl has a 2 m horizontal opening, 0.5 m vertical opening and a 5 mm diamond mesh in the codend. Trawls had duration of 1 to 3 min of effective sampling (bottom time) at a speed of 2 knots. Catches were sorted out to species and standardized abundances of callionymid species (individuals per 500 m2) were obtained by calculating the sampled surface (distance covered × beam trawl horizontal opening). Results. Callionymus reticulatus is recorded from the Balearic Islands for the first time; the specimens are described and illustrated. Conclusions. The new record confirms that the species is still extant in the Mediterranean. A key to Mediterranean callionymid fishes is provided to distinguish C. reticulatus from other species of the family in the area. The callionymid fish fauna of the Mediterranean now comprises 11 species, including three Lessepsian migrants originating from the Red Sea. [ABSTRACT FROM AUTHOR]

The Southern King Crab (SKC), Lithodes santolla , has supported a growing fishery in San Jorge Gulf (Patagonia, Argentina) since 2011. This fishery is developed by vessels called crabbers. SKC is also caught as bycatch in the Patagonian shrimp fishery, a major crustacean fishery in the Southwestern Atlantic Ocean. In this work, we characterized SKC bycatch in shrimp fishery and compared 1994–1996 data (which reflected little fishing impact) and 2011–2012 data (at the beginning of the current SKC fishery by crabbers in San Jorge Gulf), to determine the particular effects of bycatch on the SKC population. The frequency of occurrence of SKC in shrimp hauls was 84.08%. However, the relative abundance was low, in most of the hauls SCK represented less than 5% of the capture. Between 2006 and 2011, the estimated SKC bycatch was 2432 tn/year. Frequency of occurrence and abundance were higher in the same area where crabbers operate. SKC bycatch is commonly discarded, but, in 18% of the hauls, SKC are processed on board, although this is illegal. Mortality estimated at the beginning of handling was 19%, but this value may be greater due to the long time of onboard handling. SKC bycatch include critic stages of its life cycle such as juveniles, ovigerous females and molting individuals. Juveniles represented 26.9% of the total SKC bycatch, while ovigerous females represented 28.1%. Sex ratios and male size showed no differences between 1994–1996 and 2011–2012, whereas the proportion of ovigerous females decreased between both periods. This decrease can be related to the interference of trawlings in their reproductive migration to coastal waters or in their mating grounds. We consider that the main problem of SKC bycatch is the detrimental effects on its reproductive potential due to the increase in the proportion of non-ovigerous females and the mortality of ovigerous females along with extensive handling, which can also result in a significant egg loss. [ABSTRACT FROM AUTHOR]

Copyright of Brazilian Journal of Oceanography is the property of Instituto Oceanografico da Universidade de Sao Paulo and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

In this paper the discard ban policy within the Portuguese fisheries sector is discussed and the opportunities and impact in the fisheries economy that arise from sales of unwanted fish under the new landing obligation are evaluated. The decadal mean price of fish (€/kg, adjusted for inflation) rose from the 1940s until the 1970s, dropping thereafter. The yearly averaged economic income estimated for discards sales between 1969 and 2009 ranged from 419345€ to 2164379€. Discard ban sales could contribute from 10% to 53% of the total landed value and 9-34% of the total catches (landings + discards). Under a discard ban policy, the fishing sector with the largest economic contribution for total discards sales would be multispecies (54%), followed by trawl (26%) and seine (20%). On average, fishing sales contributed with 0.63% to gross domestic production (GDP) between 1938 and 2009. Discard sales can increase 1.07-1.46 times more than the fish landing contribution to GDP. After 1983 the average landings/imports economic ratio was 0.28:1, which means that fish imports surpassed landings economic value 3.57 fold. The discard ban policy can create economic opportunities in the national context thus helping to revitalize some specific fisheries sectors. [ABSTRACT FROM AUTHOR]

Small-mesh otter trawls, which use 76 mm or less codend mesh sizes, are considered "exempt" gears in some fishery management plans in the US. In New England, small-mesh trawls are utilized to capture small-bodied Northern shrimp ( Pandalus borealis ), silver hake ( Merluccius bilinearis ), and longfin inshore squid ( Doryteuthis pealeii ), which are too small to be retained by traditional “large-mesh” groundfish trawls with 165 mm mesh size codends. Due to small-mesh codends, these fisheries have historically discarded large amounts of important, juvenile groundfish species along with other bycatch species. Bycatch reduction strategies in these fisheries have focused on the design and implementation of bycatch reduction devices (BRDs) that separate target and bycatch species within the trawl. Species separation in small-mesh trawls often rely on behavioral differences between target and bycatch species, which are typically determined using under water video recordings. Behavioral differences, which occur at the BRD, allow the capture of targeted species and the escape of bycatch species. This paper reviewed BRD research and implementation in these fisheries, and discussed existing issues and future directions for research and development. This review suggests that: (1) the Northern shrimp fishery can improve bycatch reduction by combining additional BRDs with the Nordmøre grid, and preferably the BRDs should be placed in the front part of the trawl to reduce bycatch stress and injury; (2) the silver hake fishery should be allowed more BRD options throughout its fishery; (3) and the longfin inshore squid fishery should apply drop-chain-style trawls to reduce the capture of demersal species, but more research remains to reduce the capture of schooling, pelagic fish. [ABSTRACT FROM AUTHOR]

In 2012, the North Pacific Fishery Management Council initiated the process of designing a new management structure for the Gulf of Alaska trawl groundfish fleet. The new program is currently structured as a catch share program and driven by the need to end the ‘race for fish’ and provide the trawl fleet with the tools to reduce bycatch. To date much of the discussion among policy makers and stakeholders has centered on community protection measures and how best to avoid the negative social and economic impacts of catch share programs including impacts to crew, consolidation and the flight of quota and resource wealth from Gulf of Alaska fishery dependent communities. This paper examines how community protection measures related to the distribution of benefits and access to fishery resources are considered and challenged in the North Pacific today. Special attention is given to the ongoing debate surrounding the potential inclusion of an initial allocation to place-based Gulf of Alaska communities via a Community Fishing Association. As part of this effort, this paper examines the political space and underlying power dynamics in which consideration of alternatives to the commodification of fishing rights occurs. [ABSTRACT FROM AUTHOR]

Fisheries management may impact on a range of seabirds’ traits such as foraging behavior. There is an extensive hake fishing closure in Argentine waters (HFC) where trawling is banned. The concentration of fishing effort in the boundary of this area triggered the question of a potential negative effect of seabird bycatch in such area. The distribution of seabirds attending vessels and their bycatch rates was explored as well as the foraging behavior of Black-browed albatrosses (BBA, Thalassarche melanophris ) and Southern Giant Petrels (SGP, Macronectes giganteus ) in relation to the HFC. For this, 55 satellite transmitters were deployed on the birds and discrete behavioral mode was inferred using state-space models. Seabird attendance at trawlers and bycatch data were obtained from on-board observers. The spatial distribution of the birds’ bycatch was concentrated in the boundary of the HFC and the distance to the boundary had a significant effect on the interactions. The spatial modeling of seabird attendance revealed a similar pattern with core areas in the margins of the HFC. The bulk of the core foraging areas of BBAs and SGPs were concentrated in waters adjacent to the HFC. Besides, the time spent foraging in the boundaries of the HFC was greater than inside the HFC. The study highlights that the “exporting effect” due to the concentration of fishing effort and seabird foraging in bordering areas may increase seabird bycatch in the neighboring waters. Hence, the design of management measures for seabird bycatch should contemplate regulations to address these negative side effects. [ABSTRACT FROM AUTHOR]

The overfishing of large vertebrates and shellfish is the first major disturbance to all the valuable coastal ecosystems that have been studied. However, usable logbook data has not been required or of concern in many small-scale fisheries operating in the coastal or offshore regions, rendering impact evaluation and further management difficult. Various studies have taken advantage of vessel monitoring systems (VMSs) that were originally developed for purposes such as surveillance, to derive high-resolution spatiotemporal effort data or further develop logbook-like data. These systems are usually installed on large-scale fishing vessels but seldom on small-scale vessels. Taiwan provides fuel subsidies to fishery operations, evaluated according to active moving hours at sea, as calculated with customized voyage data recorders (VDRs) that have been installed on most small-scale offshore fishing vessels. The device provides temporal position and speed data similar to that of VMSs, not in real time but with cheaper device cost, no data transmission fee and higher resolution at 3-min intervals. This paper takes the offshore trawl fishery of southwestern Taiwan as example to demonstrate that the VDR data used for subsidy evaluation could also be used for high-resolution effort estimation. After briefly documenting the development of Taiwanese trawl fisheries and the application of VDR in Taiwan, the paper proposes a simple five-step procedure for managers to categorize major fishing patterns of fisheries by reviewing the speed and track profiles of vessels on a trip-by-trip basis, and finally to develop speed criteria for defining fishing efforts. [ABSTRACT FROM AUTHOR]

The focus of US fisheries regulations has changed from expanding fishing effort to protecting resources for current and future use. Regulations, enforcement, and compliance have changed and grown over the last forty years. Members of both the enforcement and commercial trawl fishing communities speculate and complain about regulatory compliance, often from opposite perspectives. A small research project in Oregon studied the relationship between these communities and regulation compliance. Although a difference was noted in the relationships between the varied levels of enforcement and trawl fishermen, this did not constitute a shift in compliance; compliance remained high with participants from both communities reporting that the fishermen have “little choice but to follow the rules.” What varied was communication within and between these communities, and the amount of control participants’ felt they had in regulation development. A small glimpse into the relationships within and between these communities offers insights into the factors that may impact fisheries, regulation development and enforcement, and communication within and between these interdependent, occupational communities. [ABSTRACT FROM AUTHOR]

Unintended bycatch of depleted or vulnerable marine species is an unsolved conservation issue that undermines the sustainability of fisheries worldwide. In Canada, policy incentives to address bycatch of vulnerable species-at-risk have become more prominent in recent years. Yet bycatch risk has been difficult to quantify and mitigate, in part due to large data gaps in fisheries observation and monitoring. Here we suggest the use of novel modelling frameworks to optimize spatial management strategies for bycatch mitigation. We utilize spatiotemporal modeling of fisheries-independent survey data to predict high-risk regions for three at-risk skates (family Rajidae) in Atlantic Canada. We use these identified regions to evaluate the relative reduction in bycatch risk that can be expected by closing targeted bycatch-protection zones on the western Scotian Shelf to bottom-trawl fishing, and further examine the relative costs to the fishing industry that such closures may impose. We show that when closures are precisely targeted on high-bycatch risk areas, relative costs to industry are minimal by affected fishing area (1.25 ± 0.62 % total area) or displaced landings (0.28 ± 0.14 % by weight of catch). To reduce bycatch risk by 50 % for all three vulnerable skates, less than 10 % of landed catch weight is displaced. These results can be used to reduce bycatch encounters for any endangered, threatened or protected species through spatially targeted conservation measures. We conclude that new approaches to the analysis and mitigation of spatial-temporal bycatch patterns can help to meet regulatory or market-driven requirements for bycatch reduction at low cost. [ABSTRACT FROM AUTHOR]

The UK is a leading nation in the development of large offshore wind energy installations (OWFs). Since 2000, the UK has installed 2610 turbines covering over 2000 km2 of UK seas. As these sites overlap with historic fishing grounds as well as Marine Protected Areas it is important to understand the relationship between the presence of these OWFs and fishing activity to assess the extent to which OWFs could act as de facto MPAs with respect to fisheries management, providing other environmental impacts are mitigated. We assessed the extent to which the fishing activity of vessels using bottom-contacting mobile gears (trawls, dredges and demersal seines) were impacted by the construction of 12 offshore windfarms in the UK EEZ. Using publicly available Global Fishing Watch fishing effort data, we found fishing rate from vessels using bottom-towed gear was reduced by 77 % following OWF construction in 11 of the 12 sites studied. A decline in bottom-towed fishing activity was recorded in OWFs where turbines were constructed in a densely aggregated patch, and an increase in fishing activity where turbines were positioned as several distinct aggregated patches within the site. We conclude that bottom-towed fishing activity is affected by turbine layout, with OWFs likely offering some protection to the benthic environment from bottom-towed gear. We suggest this reduction in bottom-towed fishing provides space for co-location opportunities and note that consultations on domestic MPA designations should involve offshore wind stakeholders in terms of OWF 'co-location' with and 'avoidance' of MPAs. [ABSTRACT FROM AUTHOR]