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There is general pressure throughout the world's fisheries for the industry to have greater involvement not only in the development of fishing gears but also in the testing and documentation of their effect. In the European Union, the Common Fisheries Policy of 2013, together with the proposed reform of the technical measures regulation, highlights the need for greater flexibility in fisheries through increased stakeholder involvement. To achieve this flexibility, there is a need for additional fishing gears available to the fishermen. A way to facilitate this is to have the industry take part in the development and testing of fishing gears, as well as collect data on their performance. However, to have a successful industry-collected data programme, fishermen have to be able to collect data on the length of a portion of the catch. In this study, we determine how many individuals need to be measured to correctly evaluate the relative selective performance of a new gear compared to a standard gear. The evaluation was carried out by analysing catch ratio curves, their associated uncertainties, and the trade-offs between uncertainties and sampling effort. Results show that with relatively small sample sizes (500 to 1000 individuals) it is possible to correctly evaluate the performance of a gear for a given species. By having the industry develop and test their own gears, as well as being involved in the collection of data, the number of potential gear solutions available to address the different issues emerging in the fisheries is increased.

Derelict abandoned, lost and discarded fishing gear have profound adverse effects. We assessed gear-specific relative risks from derelict gear to rank-order fishing methods based on: derelict gear production rates, gear quantity indicators of catch weight and fishing grounds area, and adverse consequences from derelict gear. The latter accounted for ghost fishing, transfer of microplastics and toxins into food webs, spread of invasive alien species and harmful microalgae, habitat degradation, obstruction of navigation and in-use fishing gear, and coastal socioeconomic impacts. Globally, mitigating highest risk derelict gear from gillnet, tuna purse seine with fish aggregating devices, and bottom trawl fisheries achieves maximum conservation gains. Locally, adopting controls following a sequential mitigation hierarchy and implementing effective monitoring, surveillance and enforcement systems are needed to curb derelict gear from these most problematic fisheries. Primary and synthesis research are priorities to improve future risk assessments, produce the first robust estimate of global derelict gear quantity, and assess the performance of initiatives to manage derelict gear. Findings from this first quantitative estimate of gear-specific relative risks from derelict gear guide the allocation of resources to achieve the largest improvements from mitigating adverse effects of derelict gear from the world’s 4.6 million fishing vessels.

Ocean plastic can persist in sea surface waters, eventually accumulating in remote areas of the world’s oceans. Here we characterise and quantify a major ocean plastic accumulation zone formed in subtropical waters between California and Hawaii: The Great Pacific Garbage Patch (GPGP). Our model, calibrated with data from multi-vessel and aircraft surveys, predicted at least 79 (45–129) thousand tonnes of ocean plastic are floating inside an area of 1.6 million km 2 ; a figure four to sixteen times higher than previously reported. We explain this difference through the use of more robust methods to quantify larger debris. Over three-quarters of the GPGP mass was carried by debris larger than 5 cm and at least 46% was comprised of fishing nets. Microplastics accounted for 8% of the total mass but 94% of the estimated 1.8 (1.1–3.6) trillion pieces floating in the area. Plastic collected during our study has specific characteristics such as small surface-to-volume ratio, indicating that only certain types of debris have the capacity to persist and accumulate at the surface of the GPGP. Finally, our results suggest that ocean plastic pollution within the GPGP is increasing exponentially and at a faster rate than in surrounding waters.

This contribution presents a synthesis, via a semilogarithmic regression, of estimates of the slow increase of technological efficiency, or \"creep factor,\" as estimated by various authors for a number of demersal and pelagic fisheries. This factor is used in fisheries science to adjust for the gradual increase in the effectiveness of fishing gear resulting from the successive introduction of technological improvement to fishing gear and vessels. Altogether, 51 estimates of this creep factor, mostly around 2–4%/yr and covering periods from 4 to 129 yr, were assembled or newly calculated from secondary data and shown to decrease as the period covered increased. This finding is compatible with the hypothesis that creep factors are usually estimated and published to correct for the introduction of an effective new technology over a short period of time. We suggest that estimates obtained in this fashion cannot be applied to long-term analyses and propose instead our empirical relationship, derived from estimates of creep factor and the number of years covered in a study. Also, our study confirms that technology creep must be included in all analyses involving time series of fishing effort, particularly if they exceed one decade in temporal coverage.

A key challenge in contemporary ecology and conservation is the accurate tracking of the spatial distribution of various human impacts, such as fishing. While coastal fisheries in national waters are closely monitored in some countries, existing maps of fishing effort elsewhere are fraught with uncertainty, especially in remote areas and the High Seas. Better understanding of the behavior of the global fishing fleets is required in order to prioritize and enforce fisheries management and conservation measures worldwide. Satellite-based Automatic Information Systems (S-AIS) are now commonly installed on most ocean-going vessels and have been proposed as a novel tool to explore the movements of fishing fleets in near real time. Here we present approaches to identify fishing activity from S-AIS data for three dominant fishing gear types: trawl, longline and purse seine. Using a large dataset containing worldwide fishing vessel tracks from 2011-2015, we developed three methods to detect and map fishing activities: for trawlers we produced a Hidden Markov Model (HMM) using vessel speed as observation variable. For longliners we have designed a Data Mining (DM) approach using an algorithm inspired from studies on animal movement. For purse seiners a multi-layered filtering strategy based on vessel speed and operation time was implemented. Validation against expert-labeled datasets showed average detection accuracies of 83% for trawler and longliner, and 97% for purse seiner. Our study represents the first comprehensive approach to detect and identify potential fishing behavior for three major gear types operating on a global scale. We hope that this work will enable new efforts to assess the spatial and temporal distribution of global fishing effort and make global fisheries activities transparent to ocean scientists, managers and the public.

Bangkau Village is one of the swamp areas with significant potential as a fish producer in South Kalimantan. This study aimed to identify the types of fishing gear used during the rainy season, determine the composition and proportion of the catches, and analyze the diversity, uniformity, and dominance indices. The experimental fishing method involved testing fishing operations using the fishing gear found in Bangkau Village, with sampling conducted at each location three times, one week apart. The results revealed that the fishing gear used included tempirai kawat, hancau, lalangit, pangilar , and sesuduk . Ten fish species were caught, with the following proportions: Trichopodus trichopterus 4.38%, Trichogaster pectoralis 28.19%, Helostoma temminckii 1.77%, Anabas testudineus 13.75%, Belontia hasselti 0.90%, Channa lucius 0.009%, Betta picta 1.17%, Dermogenys megarrhamphus 0.23%, Clarias batrachus 2.03%, and Monopterus albus 2.52%. The diversity index was 1.07, which falls under the medium category, the uniformity index was 0.47, indicating a small population with depressed communities, and the dominance index was 0.5, signifying unstable community dominance, meaning certain species dominated others.

Fishing gear from just five regions could account for most of the floating plastic debris in the 'North Pacific garbage patch', a vast swathe of the North Pacific Ocean that holds tens of thousands of tonnes of plastic. A sea of plastic The contaminated area was discovered in 1997 when a ship's crew noticed plastic littering a remote stretch of the open ocean. The latest results and the large proportion of the debris made up by fishing nets indicate that fishing - spearheaded by the five countries and territories identified in the study - is the main source of plastic in the North Pacific garbage patch.

Boat Lift Net is one of the active fishing gears in the West Coast, Sumatera Utara with the main catch of Sardinella ( Sardinella sp.). Fishermen from Boat Lift Net fishing gear still use traditional methods in the form of natural signs at certain times to look for fish. This has an impact on the effectiveness of fishing which is less accurate. This study seeks to identify the fishing season index for Sardinella ( Sardinella sp.) by analyzing the catch and the quantity of fishing trips. The method of determining the fishing season index in Western Waters provides an accurate fishing season for fishermen. The results of the analysis of the fishing season index of 2018-2022 in Western Waters show that the peak season of Sardinella ( Sardinella sp. ) fishing occurs in June-October which occurs in the eastern season to the middle of the second transitional season and in April in the first transitional season. The highest fishing season index for tembang (Sardinella sp.) was recorded in September, at the start of transition season II, with a value of 124.27%. Conversely, the lowest index value was observed in November, at the end of transition season II, with a value of 82.5%.

Over the past three decades, incidental bycatch has been the single most frequent verified cause of death of the endangered Saimaa ringed seal ( Pusa hispida saimensis ). Spatial and temporal fishing closures have been enforced to mitigate bycatch, which is mainly caused by the gillnets of recreational fishers. In this study, we employed an array of statistical machine learning methods to recognize patterns of death and to evaluate the impacts of annual fishing closures (15 th April–30 th June) on the recovery of the Saimaa ringed seal population during 1991–2021. We additionally used the potential biological removal (PBR) procedure to assess bycatch sustainability. The study shows that gillnet restriction areas are reflected in the timing of juvenile bycatch mortality of the Saimaa ringed seal. In the 1990s, peak mortality occurred at the beginning of June, but as the restrictions expanded regionally in the 2000s, the peak shifted to the beginning of July. Longer temporal coverage of annual closures would have improved juvenile survival. The study also shows that estimated bycatch mortality is higher than observed: the estimated bycatch averaged approximately two unobserved bycatches per one observed bycatch. Despite the continuing bycatch mortality, a larger number of juveniles nowadays survive to the age of 15 months due to fishing closures, and the population (some 420 individuals) has increased an average 4% per year between 2017 and 2021. However, human-caused mortality limits (PBR) were exceeded by observed bycatch only, which could lead to population depletion in the long run.

Illegal and unreported fishing contributes to overexploitation of fish stocks and is a hindrance to the recovery of fish populations and ecosystems. This study is the first to undertake a world-wide analysis of illegal and unreported fishing. Reviewing the situation in 54 countries and on the high seas, we estimate that lower and upper estimates of the total value of current illegal and unreported fishing losses worldwide are between $10 bn and $23.5 bn annually, representing between 11 and 26 million tonnes. Our data are of sufficient resolution to detect regional differences in the level and trend of illegal fishing over the last 20 years, and we can report a significant correlation between governance and the level of illegal fishing. Developing countries are most at risk from illegal fishing, with total estimated catches in West Africa being 40% higher than reported catches. Such levels of exploitation severely hamper the sustainable management of marine ecosystems. Although there have been some successes in reducing the level of illegal fishing in some areas, these developments are relatively recent and follow growing international focus on the problem. This paper provides the baseline against which successful action to curb illegal fishing can be judged.