Catch Distribution Research Articles

Estimating Fishing Exploitation Rates to Simulate Global Catches and Biomass Changes of Pelagic and Demersal Fish

AbstractRobust projections of future trends in global fish biomass, production and catches are needed for informed fisheries policy in a changing climate. Trust in future projections, however, relies on establishing that models can accurately simulate past relationships between exploitation rates and ecosystem states. In addition, historical simulations are important to describe how the oceans have changed due to fishing. Here we use fisheries catch, catch‐only assessment models and effort data to estimate regional fishing exploitation levels, defined as the fishing mortality relative to fishing mortality at maximum sustainable yield (F/FMSY). These estimates are given for large pelagic, forage and demersal fish types across all large marine ecosystems and the high seas between 1961 and 2004; and with a ‘ramp‐up’ between 1841 and 1960. We find that global exploitation rates for large pelagic and demersal fish consistently exceed those for forage fish and peak in the late 1980s. We use the rates to globally simulate historical fishing patterns in a mechanistic fish community model. The modeled catch aligns with the reconstructed catch, both for total catch and catch distribution by functional type. Simulations show a clear deviation from an unfished model state, with a 25% reduction in biomass in large pelagic and demersal fish in shelf regions in recent years and a 50% increase in forage fish, primarily due to reduced predation. The simulations can set a baseline for assessing the effect of climate change relative to fishing. The results highlight the influential role of fishing as a primary driver of global fish community dynamics.

PROBLEMS FACED BY FISHERMEN IN DISTRIBUTING FISH CATCHES IN BATANG REGENCY

Indonesia as a maritime country with great marine potential should be able to provide welfare for the fishing community. However, in reality, most fishermen in Indonesia, including in Mangunsari Village, still live in poverty. This research aims to identify and analyze the problematic distribution of fish catches in Mangunsari Village. The research questions focused on infrastructure, technology, and market access constraints faced by fishermen. This research uses qualitative methods with in-depth interviews and participatory observation to explore the problems faced by fishermen. The research findings show that poor infrastructure, limited storage and preservation technology, and limited market access are the main obstacles in fish distribution. In addition, the influx of investors building the Batang Integrated Industrial Estate (KITB) and the construction of a toll road that led to flash floods also worsened the situation, forcing fishermen into debt to make ends meet. Ineffective government policies and low community participation in utilizing aid also exacerbated the condition. The findings are expected to serve as a basis for formulating more effective strategies to improve the welfare of fishing communities in Mangunsari Village.

Is my fishing gear impacting the habitat? An impact assessment in four fisheries in the Northwest Mexican Pacific

The impacts of fishing activities on habitats for commercially important species may, directly and indirectly, influence species and associated communities. These effects include those on target species, bycatch species, habitats, etc. In this study, the impact of small-scale fisheries on habitats was evaluated in four fishing communities from the Northwest Mexican Pacific. The species and size selectivity of several fishing gear were evaluated, and the spatial distribution of catches was studied to assess the impacts of fishing gear using a Consequence Spatial Analysis (CSA). Our results showed that in finfish fisheries from Guaymas and Isla Natividad, the catch of the target species represents more than 75% of the total catch and in El Rosario, the catch represents less than 50%. We assessed 42 habitat types in four communities, which were qualified with low-risk scores. The fishing gears used to target commercial species are selective to optimal sizes above their maturity size. The results contribute to improving management in data-poor fisheries by evaluating the impacts of fishing on habitats and discussing their relevance for implementation.

Environmental Influences on Illex argentinus Trawling Grounds in the Southwest Atlantic High Seas

To understand the spatial temporal distribution characteristics of Illex argentinus caught by trawl fishing vessels in the Southwestern Atlantic Ocean and their relationship with key marine environmental factors, this study analyzed the temporal and spatial changes in the fishing ground center of trawl vessels at the ten-day scale from December 2019 to May 2022, combining Chinese trawl fishing log data marine environmental data with satellite remote sensing marine environmental data. Utilizing the Maxent model, ten-day intervals were used as the temporal scale, and ten marine environmental factors, including sea surface temperature, sea surface height, sea surface salinity, chlorophyll concentration, temperature at 50 m and 100 m depth, and the meridional and zonal velocities of ocean currents were quantitatively analyzed to explore the correlation between the spatial distribution of catch and environmental factors. The study reveals that the trawl fishing grounds for Illex argentinus are divided into southern and northern grounds. The southern grounds first appear near 45°20′ S in December, gradually moving southeastward in February and March. The northern grounds do not appear until April, near 42° S in the high seas. On the ten-day time scale, the central fishing grounds of Illex argentinus show significant spatial variability but minor interannual differences. The Maxent model results indicate that sea surface temperature and chlorophyll a concentration are the key environmental factors influencing the spatial and temporal variability of the high seas trawl fishing grounds for most of the time, with high environmental contribution rates during the fishing season. While the range of suitable habitats with an HSI > 0.6 identified by the Maxent model varies significantly between years, a pattern is observed where the range expands at the start and end of the fishing season and contracts during the peak fishing season. This suggests that a more concentrated range of suitable habitats is conducive to accurate predictions of trawl fishing grounds, enabling efficient fishing operations.

Environmental DNA as a tool to reconstruct catch composition for longline fisheries vessels

Global wild-capture fisheries are a large and diverse sector requiring various tools for fisheries-dependant data collection and effective Monitoring, Control and Surveillance (MCS). Here we present a novel protocol to collect eDNA from brine tanks onboard commercial longline vessels to reconstruct catch composition. We collected samples from nine vessels operating out of the Eastern Tuna Billfish Fishery, Australia, validating eDNA results with reliable catch data consisting of seven target and bycatch species. Environmental DNA was highly effective for detecting species retained on vessels without contamination or false positives. For four vessels, logbook data and eDNA were consistent with detections of all species. The remaining vessels detected all species except for rare catches of short-billed spearfish (Tetrapturus angustirostris). Similarities between rank abundance distributions of catch and eDNA reads were observed with logbook data mirrored when eDNA sequences were organised into rank order abundance. The method was effective at identifying highly abundant taxa retained in brine tanks- tuna (Thunnus spp.), swordfish (Xiphias gladius), marlin (Kajijia audax), and Atlantic Pomfret (Brama brama). Further research is required to validate how eDNA and other molecular monitoring tools can be scaled and applied to provide solutions for monitoring challenges in the fisheries sector.

Charting and analyzing the catch distribution of Japan’s coastal fisheries resources based on centennial statistics

Spatiotemporal changes in catches and transition of fishing grounds have been observed in various coastal fishery resources in Japanese waters in recent years. Are these changes part of cyclical fluctuations on a centennial timescale? Are these changes situations that have never been observed prior to this? Are common factors included in the long-term fluctuations among coastal fisheries resources? A total of 12 important Japanese coastal fisheries resources including fishes, shells, invertebrates, and algae were analyzed using fisheries statistics on the geographical center of catch compiled since 1894. The time series of the geographical center of catch showed a cyclical fluctuation trend over time rather than changing monotonically. The geographic center of catch in recent years (2019–2021) was located at the northeastern margin of the distribution, compared to its location since the end of the 19th century for many fishery resources. For coastal fishery resources, the situation in terms of fluctuations in the geographical center of catch is more extreme than in the past 100 years. The results of the dynamic factor analysis suggested that the state of these resources may be affected by the global ocean environment and other factors including human activities. Examining how fisheries have responded to past cyclical fluctuations may provide insight into adapting to the current rapid changes caused by climate change.

Poleward catch displacement of blackfin tuna Thunnus atlanticus in the southwestern Atlantic Ocean: Possible effect of increasing water temperatures

AbstractBlackfin tuna Thunnus atlanticus often inhabits warm waters of the western Atlantic Ocean from 40°N (Cape Cod, USA) to 22°S (Rio de Janeiro, Brazil). We recorded the first catches of the species in southern Brazil (34°S) and described its new distribution and fishing grounds. Since 2007, annual catches per trip and frequency of blackfin tuna landings increased for three oceanic fishing fleets in Southern Brazil. The spatial distribution of higher catches and the center of gravity of spatial fishing records moved poleward. Sea surface temperature anomalies for the region warmed from 1960 to 2019, and anomalies were primarily positive after 2000. Evidence suggests that the distribution of blackfin tuna moved poleward by six degrees of latitude (~660 km). The causes of this distribution extension were unclear, but ocean warming was the most likely driver.

Abundance and Distribution of Blue Swimmer Crab in Response to Environmental Variation Across Two Contrasting Estuaries

Portunid crabs are an iconic, high value species in NSW, but catches are highly variable in space and time. Substantial variation in biomass is observed in both exploited and unfished populations, and environmental effects on distribution and abundance are an important factor contributing to this variability. Predicting and responding to this variability is a challenge for management and sustainability of exploited populations. We examine spatial and temporal variation in Blue Swimmer Crab (Portunus armatus) populations, over a 2.5 year trapping survey in two temperate estuaries that differ in tidal flow and riverine input. Specifically, monthly catch rates and distribution throughout the estuary are examined alongside variation in temperature and conductivity. In Wallis Lake, the shallower estuary with a restricted entrance, both water temperature and conductivity impacted abundance and distribution of crabs but there was no evidence that pulses of freshwater flow had a major impact. For a 10 °C increase in temperature the population on average shifted ~ 700 m closer to the ocean. Males were consistently located slightly further into the estuary compared to females, but there was no convincing evidence of estuarine egression in response to lower salinity. In Port Stephens, the deeper, tidal estuary, water temperature and conductivity also impacted abundance, but while males were more dispersed than females, the distribution of crabs within the estuary did not appear to be influenced by temperature, conductivity or flow. These results highlight the links between nuanced environmental relationships and estuarine geomorphology for Blue Swimmer Crab.

Use of the raw material base of marine fish in Russian waters of the Far Eastern seas and adjacent areas of the open part of the Pacific Ocean in 2000–2020

The purpose of the work: characteristics of the raw material base of marine fish in the Far Eastern fishery basin and an assessment of the effectiveness of its use by domestic fisheries at the present stage (2000–2020).Methods used: to achieve this goal, data on biomass, catch and development of the main commercial marine fish were analyzed. Fish catches were reviewed based on operational information about the fishery based on daily ship reports from the industry monitoring system.Novelty: elements of novelty are generalized modern materials on biomass, catch and development of marine fish resources in the Far Eastern seas and adjacent waters of the Pacific Ocean. The current state of commercial fish stocks (walleye pollock, Pacific cod, saffron cod, Pacific herring, Righteye flounders, greenlings, Japanese pilchard, Chub mackerel, Pacific saury) in the Far Eastern fishing basin can be characterized as stable, and the distribution of the catch of these objects among individual fishing areas due to their significant volumes is practically determines the distribution of catch of both quota and non-quota species of marine fish. Scientific information support for the above-m entioned fish is at a high level, their biological condition is generally favorable, and the dynamics of their numbers is regulated mainly by habitat variability.Practical significance: the results of this study can be used in forecasting the dynamics of aquatic biological resources, and the results obtained on marine fish stocks and fisheries will improve the efficiency of using their raw material base.

Zonal distribution of the stock of blue whiting <I>(Micromesistius poutassou)</I> in the North-East Atlantic in 2010–2020

In the management of the blue whiting fishery, the problem of exceeding the scientifically justified catch remains due to the lack of an agreement on national shares between Coastal States. In order to obtain additional data necessary to reach an agreement, a NEAFC Working Group was established by the Coastal States to form a report on the zonal distribution of the reserve. Until March 2022, a Russian specialist took part in the work of the group. The article analyzes the main results of the distribution of both international catches of blue whiting and biomass of the stock in accordance with the data of the international survey, according to the NEA economic, fishing zones and international waters for the period 2010–2020 was conducted. It was found out that during this period the largest part of the blue whiting of the stock was distributed in the fishing zone of the Faroe Islands, exclusive economic zones of the EU, Great Britain and economic zone of the Norway. The economic zones of Ireland (EU) and Great Britain were the main «holders» of the spawning stock with the most active fishing in the spring, while the Faroese fishing zone is the most significant zone through which the main migrations of a significant part of the stock pass throughout the year. The waters of the Norwegian economic zone were the main habitat of immature juveniles and feeding fish, to a somewhat lesser extent this applied to the waters of the Iceland economic zone. The results of this work can be used as a basis for dividing the total available catch of the blue whiting into national shares and can accelerate the achievement of an agreement between the Coastal States.

The Characteristics of Feeding Migrations of Hatchery-Reared Pacific Salmon Juveniles in the Sea of Okhotsk Basin and Adjacent Pacific Waters in the Autumn–Winter Period (Regional Identification, Abundance, Distribution of Catches, Biological Characteristics, and Mortality Rate Estimates)

The Characteristics of Feeding Migrations of Hatchery-Reared Pacific Salmon Juveniles in the Sea of Okhotsk Basin and Adjacent Pacific Waters in the Autumn–Winter Period (Regional Identification, Abundance, Distribution of Catches, Biological Characteristics, and Mortality Rate Estimates)

Pemetaan Sebaran Rajungan yang ditangkap menggunakan Bubu Di Perairan Pesisir Barat Lampung

The Pesisir Barat of Lampung is one of the locations that has great opportunities for capture fisheries activities in Lampung. The abundant potential of these waters means that people in Pesisir Barat Regency earn income from fishing along these waters. Fishermen still catch fish using traditional tools using small boats (jukung). The vast waters with muddy and sandy water substrates make fishermen use fishing gear that is cheap, easy to operate and environmentally friendly. The trap fishing gear is a passive fishing gear operated by fishermen whose main catch is crab. The aim of this research is to map the distribution of crab catches using trap fishing gear. This research was carried out from June 2023 to September 2023. The research location was carried out in West Coastal Waters. Mapping crab fishing areas begins with identifying crab fishing areas. Identification of crab fishing areas is carried out using a survey method on three indicators, namely the location of fishing operations, catch results and environmental conditions. These results show that the distribution of crabs using trap fishing gear on the West Coast is at the Fishing Ground in Kuala Stabas Waters, Bengkunat Bay Waters and Labuhan Tapokan Waters with the number of crabs on LED trap fishing gear being 250 and the number of crabs on trap fishing gear without LEDs being 250. 119 Tails

Spatial Distribution of Major Fish Species Catches and Their Relationship with Environmental Factors in the Beibu Gulf, South China Sea

This study focused on major fish species caught from different ecological habitats to analyze the habitat changes in economically important fish in the Beibu Gulf. The maximum entropy model was constructed based on the data from 26 voyages obtained through the otter trawl fishery stock surveys conducted in the Beibu Gulf from 2006 to 2018. A total of 10 taxa of major fish catches, belonging to 4 families, 1 genus, and 5 species, were analyzed for their distribution characteristics in potential habitats during various ecological periods, specifically the withered and high-water periods, as well as their relationships with crucial environmental factors. During both the withered and high-water periods, the average area under the curve was 0.927, and all models had values exceeding 0.9. Salinity was identified as the principal factor during both periods. The salinity niche of Acropoma japonicum and the primary productivity niche of Sciaenidae were identified as the most restricted factors. The total distribution area of potentially suitable regions for major fish catches extended between 106°30′–109°45′ E and 17°30′–20°45′ N, and the area was lesser during the withered period. During the withered period, the distribution areas of Sciaenidae, Leiognathidae, and Saurida increased, while the distribution area of Trachurus japonicus increased during the high-water period. Sciaenidae and Trachurus japonicus exhibited the highest rates of change at 6.22% and 10.92%, respectively. This indicates that the high-water period may expand the range of suitable habitats for large catches that have an ideal habitat status in the Beibu Gulf. Therefore, it is crucial to anticipate the potential fish habitats in the Beibu Gulf and clarify their spatial distribution patterns.

Ecosystem Management Policy Implications Based on Tonga Main Tuna Species Catch Data 2002–2018

Despite the crucial role played by international and regional tuna fisheries in facilitating the successful implementation of the ecosystem approach to fisheries management, there exist disparities in viewpoints among these stakeholders, resulting in gaps between regional fisheries management and local communities. Nevertheless, the Tongan government, under the Ministry of Fisheries, is dedicated to the efficient management of its tuna resources, aiming to establish it as the preferred and optimal approach for ensuring the long-term sustainability of its tuna fisheries and the ecosystem services they provide to the community. Recognizing that an appropriate legal, policy and institutional framework is in place for sustainable management of tuna, the first part of this paper presents a review of current Tonga fisheries laws and policies for its tuna fisheries. This review reflects the implementation of an information-based management framework, namely the Tonga National Tuna Fishery Management and Development Plan. The tuna fisheries in Tonga mainly catch albacore (Thunnus alalunga), bigeye (Thunnus obesus), skipjack (Katsuwonus pelamis), and yellowfin (Thunnus albacares) tuna. These tuna species are caught within Tonga’s exclusive economic zones and play a crucial role in the country’s economy; hence, it is crucial to examine the spatio-temporal distributions of their catch in relation to their environmental conditions. In pursuit of this goal, the tasks of mapping (i) the spatio-temporal distribution of catch landed at ports and (ii) the spatio-temporal of environmental conditions were performed. The study utilizes longline catch per unit effort data spanning from 2002 to 2018 for albacore, bigeye, skipjack, and yellowfin tuna. It also incorporates data on environmental conditions, including sea surface temperature, sea surface chlorophyll, sea surface current, and sea surface salinity. Additionally, the El Nino Southern Oscillation Index is mapped in relation to catch data to examine the potential effects of climate change on the tuna catch. Results show that bigeye, skipjack, and yellowfin CPUE show a central–northernmost distribution and are primarily caught between latitudes 14° S–22° S, while albacore, shows a central–southern distribution. The highest CPUE for all species are in latitudes 15.5° S–22.5° S and longitudes 172.5° W–176.5° W. The data indicate that sea surface current velocities range from −0.03 to 0.04 ms−1, sea surface salinity ranges from 34.8 to 35.6 PSU, sea surface chlorophyll concentration varies from 0.03 to 0.1 mg m−3, and sea surface temperature fluctuates seasonally, ranging from 18 °C to 30 °C. Mapping also reveals that times of reduced catches in Tonga coincide with periods of moderate to strong El Nino events from 2002 to 2018.

Distribution of catches of aquatic biological resources in the Russian waters of the Bering Sea by areas, dates and fishing gear

The purpose of the work: revealing the features of the distribution of the catches of aquatic biological resources by area, timing and fishing gear in the course of modern fishery in the Russian waters of the Bering Sea. Methods used: the catches of marine fish and invertebrates were considered based on operational information on the fishery according to the data of daily ship reports of the sectoral monitoring system. The ratio of the catch of the main species of aquatic biological resources and by-catch objects in 10 fishing gear was analyzed according to the data of 50 marine and 28 coastal expeditions. Novelty: elements of novelty are generalized materials on the spatial and bathymetric distribution of the catch of the main fishing objects for the fishing industry in the western part of the Bering Sea for the period 2003–2021. The distribution of catches of aquatic organisms is given by types of vessels used in the fishery, depths and terms of fishing, as well as various fishing gear. Data on the ratio in commercial catches of both individual fish species and some species in the combined groups of «flounders», «rockfishes», «sculpins», «skates» and «grenadiers» are presented. Practical significance: the results of this study can be used in forecasting the dynamics of stocks of aquatic biological resources, creating a system of interlocked quotas and formulating recommendations for the transition of specialized fisheries to multi-species fisheries.

Geo-spatial distribution and trends of trawl catch and bycatch off the south Konkan coast, Maharashtra, India

Trawl fishing is well-known for its high catch rate, but due to its non-selective nature, it is now widely acknowledged to have an impact on biodiversity and habitat. The geographical and temporal aspects of trawl catch, bycatch, discard, and ichthyofaunal trawl diversity along the south Konkan coast of Maharashtra, India, are contemplated in the current study. The data of 177 georeferenced trawl hauls, towed between 15°53’38”N to 17°34’52”N latitude and 72°54’29”E to 73°25’48”E longitude, revealed that maximum bycatch (70–110 kg/haul) and discard (60–110 kg/haul) regions were found towards the southern direction, near ecologically sensitive estuarine areas off the south Konkan coast, Maharashtra. The post and pre-monsoon seasons were found to be much more productive in terms of catches, while the post-monsoon and winter seasons had the highest species diversity 38.15% and 33.86%, respectively, with the winter season having higher discard rates. In the present study, bycatch contributed nearly 49% of the total catch, with the maximum catch per hour recorded in October (62.20 kg) and the discard per hour in January (14.59 kg). There were 134 different species of fish and shellfish recorded, and the family Carangidae (8.21%) was prominent in terms of species richness, followed by Penaeidae (6.72%), Clupeidae (5.22%), Engraulidae (5.22%), and Sciaenidae (4.48%). The results of various biodiversity indices confirmed that the studied region is blessed with rich and evenly distributed biodiversity. The mapped predictive values of trawl fishing showed a high fishing pressure zone towards the south off the Maharashtra coast, and it highlighted the need for suitable strategies for the conservation and management of fisheries resources to achieve long-term sustainability in that region.

Diversity and Distribution of 18 Cephalopod Species, and Their Link with Some Environmental Factors in the NW Pacific

Some cephalopods are important fishery resources, with some major economic species living in pelagic waters, possessing short life history cycles, and responding strongly to environmental changes. The analysis of cephalopod community species composition, catch distribution, and their relationship with environmental factors in important marine areas can provide a basic reference for cephalopod biogeography and resource development and utilization. In this study, based on the cephalopod survey data in the spring of 2015 and summer of 2016 in the Pacific Ocean, we analyzed the cephalopod species composition, diversity index (the Margalef richness index, Shannon–Wiener diversity index, and Pielou uniformity index), main contributing species, and catch distribution in the two seasons of spring and summer in the Pacific Ocean. We also analyzed the relationship between cephalopod catch, each diversity index, and environmental factors in each season using the GAM model. The results show that 18 species of cephalopods were captured in the spring and summer, the Margalef richness index, Shannon–Wiener diversity index, and Pielou uniformity index in summer was higher than that in spring; the average catch biomass in spring was significantly higher than that in summer. The main contributing species in spring was Todarodes pacificus, while the main contributing species in summer was Ommastrephes bartramii. The interaction of the “longitude” and “latitude” has a great impact on cephalopod catch biomass in spring, and “sea surface temperature” has a great impact on cephalopod catch biomass in summer. The results of the study can provide a basic reference for the study of cephalopod diversity and resource development and utilization in the Pacific Ocean.

Characteristics of feeding migrations of hatchery juveniles of pacific salmon in the basin of Okhotsk Sea and adjacent Pacific waters in the autumn-winter period (regional identification, abundance and distribution of catches, bio-logical indices, estimates of mortality)

Long-term data on feeding migrations of hatchery pacific salmon (pink and chum salmon) in the Okhotsk Sea and adjacent Pacific waters in the autumn-winter of 2011–2021 are generalized. The study is based on materials (otolith samples, biological indices) collected in the trawl surveys conducted by TINRO, as well as on international statistics on releases and tagging of pacific salmon at the Russian and Japanese hatcheries. The main patterns of intraspecific structure, migration routes, spatial distribution, and volumes of catch are determined for these species, as well as the size-weight parameters of fish originated from different regions. Natural mortality of salmon juveniles at the stage of migration from the coastal zone to the open sea is estimated at systemic level for the first time.

Features of the russian fishery of capelin Mallotus villosus of the Barents sea in 2018 and 2022

On the basis of fishing statistics and research by observers on fishing vessels, an analysis was made of the distribution of capelin catches, the main indicators of fishery (effort, average daily capacity) were considered; length composition of the species was analyzed. It has been established that in 2018 and 2022 the most conductive conditions for capelin fishery, both in terms of capacity and the length composition of the species, were formed in the second half of February and in March in the economic zone of Norway. The reasons for the incomplete realization of the russian quota of capelin in 2018 were the non-optimal timing of fishing by the main group of vessels, in 2022 – an insufficient number of fishing efforts. In March 2018 and 2022, difficult weather prevailed at the fishery, which could prevent the effective realization of the russian quota of capelin.

Brief results of research on scallops off the northern Kuril Islands in autumn 2022

The purpose of the work: to collect materials for assessing the state and dynamics of scallop stocks in the North Kuril zone, to study the spatial structure of settlements, to monitor the dynamics, distribution and composition of commercial catches in 2022.Materials and Methods: The work was carried out on a specialized rowing vessel “Vladimir Nikora” performed 210 dredging in the area limited by coordinates 49°20'N 49°30'N. and 154°57'E154°53'E at depths of 79-170 meters. The data collection tool is an industrial scallop dredge with a working width of 3.7 m (scallop dredge 1.04 / 3.74 m). The material type of the scallop dredge bag is kapron. The length of the dredging was 0.4-0.5 miles. The research covered the water area of 23 square meters. miles. Biological analysis was carried out for 5 thousand specimens of chlamy scallops. The biological state of hydrobionts was studied according to the methods generally accepted in fisheries research. For comparability of data on the distribution of hydrobionts, the catchability coefficient of the scallop dredge was used equal to 1. The linear dimensions of the scallops were measured with an accuracy of 1 mm.The practical significance of the research: to provide commercial and biological information materials on the total allowable catches of scallops in the North Kuril.