Fishery Landings Research Articles

Domesticating the wild through escapees of two iconic mediterranean farmed fish species

Extractive fisheries and marine aquaculture share space and target species. Several regional-scale examples exist of escapees entering wild fisheries landings, yet no study has assessed the influence of aquaculture on landings at an ecosystem scale. We examined the effects of farmed fish escapes on fisheries using FAO data and published escape rates for Gilthead seabream (Sparus aurata) and European seabass (Dicentrarchus labrax). Seabream landings were significantly correlated with the estimated biomass of escaped seabream entering the wild. There was a similar pattern for seabass until 2005, but the overall relationship between landings and escapes was not significant due to the dramatic drop in catches in recent years. We argue that seabass escapees’ relatively high mortality, lower capturability, and minor ‘leaking’ from farms may obscure their influence on landings. Significant positive fisheries regime shifts were detected for both species, matching the onset of aquaculture in the Mediterranean and the period when escapees from aquaculture surpassed landings. Our results suggest that fish escapes of these two iconic species may mask wild stock overexploitation, confound stock assessments, alter genetic diversity, increase the risk of spreading pathogens and parasites, and compete with wild conspecifics while boosting fisheries landings.

Fishery status of the green tiger shrimp (Penaeus semisulcatus) in Palk Bay, in the southeast coast of India: Local and global perspectives

The green tiger shrimp (Penaeus semisulcatus De Haan, 1844), traded as Mandapam flower shrimp internationally, is large-sized shrimp and landed on the coast of Palk Bay, India. This work aimed to describe the status of its fishery and identify challenges for the better management of these resources. The estimated fishery landings of P. semisulcatus in 2022 were 7658 t, with an annual average of 6493 t from 2020 to 2022, contributing to the total penaeid shrimp landings in Palk Bay at 57.6%. The economic value of this fishery was estimated to be around $53 million USDs annually (1 USD = 83.16 INR). Between 2007 and 2022, there was a significant difference between green tiger shrimp and total penaeid shrimp landings in Palk Bay across gears and years. All shrimp from Palk Bay have export markets to Japan, the USA, China, and European countries. The average annual export of P. semisulcatus (2015-16 to 2022–23) was 3532 t ($30.9 million USDs). In 2022–23, the USA was the biggest importer of frozen shrimp, followed by China, the European countries, Southeast Asia, Japan, and the Middle-East countries. We formulated a policy guidelines framework for the management and co-management of the green tiger shrimp fishery in Palk Bay based on a precautionary approach.

Value and economic impact of fuel subsidies on the Mexican fishing industry

ABSTRACT Fuel is an important input in the fishing industry’s activities, and fuel subsidies are aimed at generating more competitiveness and encouraging development. Nevertheless, they can also create incentives for fishers to exert more effort, thereby resulting in overexploitation. This paper estimates the economic value of fuel used by the Mexican fishing industry based on the elasticity of production with respect to fuel (εC) and the value of the marginal product (ρC) through the Cobb-Douglas and Trans-Log production function. The εC and ρC were estimated to be 0.52 and USD 3.1, respectively, with the latter contributing to only 8.3% of the fuel subsidy. Furthermore, a direct relationship is evident when observing the trends and the differences in means of the average price of fishery landings and the number of subsidies between 2011 and 2019. That is, the higher the prices and/or subsidies, the higher the levels of extraction. These results have important implications for fuel management and its relationship with the extraction of fishery resources, especially in countries where a subsidy policy is applied in an attempt to support the sector, but which at the same time can have a negative impact on fishery resources.

Time series modeling of coastal fishery landings on the Southwestern Atlantic shelf: Influence of environmental drivers

AbstractTime‐series modeling of fisheries provides insights into stock tendencies and enables short‐term forecasting of landings, aiding decision makers in establishing management priorities. The Rio de la Plata Estuary and its maritime front sustain valuable fisheries for Argentina and Uruguay, with striped weakfish (Cynoscion guatucupa), whitemouth croaker (Micropogonias furnieri), and Argentine hake (Merluccius hubbsi) historically representing highest catches. However, their landings have declined in recent decades. To support resource management, we investigated the effectiveness of Autoregressive Integrated Moving Average (ARIMA) models in capturing fishery landing dynamics and providing reliable short‐term predictions. The best models exhibited a good fit and accurately captured the overall trends of landings. Residual variability unaccounted for by the model was analyzed in relation to time‐lagged environmental conditions. A wavelet coherence analysis was employed to examine the effect of the most significant variables on landings. Results revealed that environmental conditions affect differentially landings of each species as a result of their particular ecological traits. Turbidity and salinity affected mainly M. furnieri, which inhabits the innermost part of the estuary. Additionally, C. guatucupa, inhabiting the outer estuary and coastal region, exhibited a stronger association with river runoff compared to M. hubbsi, which inhabits the continental shelf. This study provides the first evidence of ARIMA models' reliability in representing the temporal evolution of catch in these fisheries, offering valuable tools for short‐term landings forecasting and facilitating sustainable management. Wavelet analysis findings will also contribute to enhancing our comprehension of trends in the correlation between environmental conditions and commercial landings.

Identification of Sparidae species based on COI and 16S rRNA DNA barcoding along the coast of Oman

Fish species belonging to the Sparidae family hold significant commercial value for Oman’s fisheries. Although 18 out of 132 known sparid species have been reported in Omani waters, accurate morphological identification remains challenging for many species. We used DNA barcoding based on cytochrome oxidase subunit І (COI) and 16S ribosomal RNA (16S rRNA) to identify commercially important sparid species. Sixty-three specimens were collected from three major Omani fisheries landings, namely Khasab, Suhar, and Salalah, spanning over 3165 km of coastline. Sequences of 16 S rRNA (521 bp) and COI (506 bp) identified 16 species by 16S rRNA, ten species by COI. Notably, Dentex gibbosus was reported for the first time in Omani waters. The identified 16 species, phylogenetically, belong to two genetically distinct groups. The interspecific genetic distances among species ranged from 0.011 to 0.279 based on 16S rRNA and 0.104–0.259 based on COI, indicating different groups within Omani waters. DNA barcoding provided high taxonomic resolution of sparid biodiversity in Oman and the surrounding region. Additionally, the study contributes to establishing a reference database for the Sparidae family of species from Oman.

Using benthic recruitment densities to forecast fisheries recruitment of American lobster in Atlantic Canada

There is limited understanding of the mechanisms underlying the marked spatial and temporal trends in landings of American lobster in Canada since the mid-1980s, and little ability to forecast changes. We built an individual-based model for three Lobster Fishing Areas (LFAs) in Canada that uses the annual density of benthic recruits in nursery grounds to generate an index of exploited biomass 6 to 10 years in the future, using von Bertalanffy growth equations complemented with inter-individual variability in growth, and regional maturity ogives and spawning probabilities to allow exclusion of ovigerous females from the exploitable biomass. We found significant positive relationships between the modelled biomass index and fisheries landings in all three LFAs. Out-of-sample validation in two LFAs (longer time series) using 1-year and 6-year reduced data sets revealed mean annual prediction errors of 11.4% and 11.2%, and 23.7% and 51.7%, respectively. Our findings strongly suggest benthic recruitment indices could help make strategic decisions concerning lobster fishing activities, and they argue for the continued and expanded monitoring of lobster benthic recruitment in Canada.

Modeling environmental effects on fishery landings: A case study of whitemouth croaker (Micropogonias furnieri) in the Southwestern Atlantic shelf

Estuaries are very productive habitats that serve as spawning and nursery grounds for fisheries species. The Rio de la Plata (RdP) Estuary and its maritime front sustain valuable fisheries for Argentina and Uruguay. Micropogonias furnieri, the coastal fish species historically representing highest catches, has declined landings in recent decades. To enhance our understanding on how natural variability influences this resource and improves its management, we analysed the effect of environmental conditions on M. furnieri’s commercial landings in the long term using generalized linear and additive models (GLMs and GAMs). Explanatory variables, with up to a 10-year lag, included sea surface temperature, turbidity, salinity, wind, river runoff, and climatological indices: El Niño-Southern Oscillation (ENSO), the Southern Annular Mode (SAM) and the Southern Oscillation Index (SOI). Time-lagged analyses for single-covariate models reveal higher deviances explained (DE) at 2, 6, 7, and 8-year lags. Turbidity and salinity, followed by wind and temperature, are the most common variables affecting catches of M. furnieri for GLMs and GAMs. The absence of significant models with only climatological indices or river discharge indicates the impact of large-scale climate fluctuations and river runoff on the RdP Estuary conditions. The best-fitting GLM model includes SAM, turbidity, and wind (DE = 78.8%), whereas the GAM model includes turbidity and wind (DE = 86.4%). Sensitivity of M. furnieri’s catches to climatic signals (ENSO, SAM, SOI) is described for the first time. Our findings provide insights for authorities to implement management measures beyond fishing quotas encompassing environmental shifts in the long-term.

Unraveling the environmental influence on inter-annual fishery yield in a small-scale gillnet fishery under Rio de la Plata influence, South America

The study focuses on understanding the influence of the environment on the relative yields of a gill net fishery operating in San Antonio Cape, Argentina. The research was conducted during five austral warm periods covering spring to summer from 2008 to 2013, aiming to assess the potential impacts of climate change on small-scale fisheries. The hierarchical species composition of 563 fishery landings encompasses 41 registered species. Among these species, Cynoscion guatucupa, Micropogonias furnieri, Mustelus schmitti, and Parona signata were found to be dominant. The species composition showed a similarity ranging from 36.22% to 57.59%, with significant differences observed among most of the warm seasons. The Multivariate Regression Tree analysis showed that the temperature was the variable with the greatest influence on the composition of the landings. During warmer conditions (>20.4 °C), the location of the draft became a significant factor, while variation in turbidity played a role in the northern zone. In colder warm conditions (<20.4 °C), the composition differed based on the volumes of Río de la Plata discharge. Specifically, the freshwater outflow was further differentiated by depth (∼9 m) at lower volumes (<20 649 m3/s) and by turbidity at intermediate values (20 649–22 908 m3/s). The vulnerability of the fishery was explained by a combination of specific ranges of various stressors. These stressors led to significant variations in the composition of fishery landings, ultimately affecting the economic income of the fishermen. By understanding the relationship between environmental factors and fishery yields, this study provides valuable insights into anticipating the potential impacts of climate change on small-scale, vulnerable fisheries.

Assessing the impact of the invasive ctenophore Mnemiopsis leidyi on artisanal fisheries in the Venice Lagoon: an interdisciplinary approach

AbstractThe sea walnut, Mnemiopsis leidyi, has invaded and expanded throughout the whole Mediterranean Sea basin. Large blooms were recorded also in the Venice Lagoon (Italy), an ecosystem rich with biodiversity which supports multiple services, including artisanal fishery production. To investigate M. leidyi impacts on lagoon artisanal fisheries, we combined fishers’ local ecological knowledge, fishery landing time series analysis, and field sampling. Firstly, we interviewed artisanal fishers to date the blooms of M. leidyi. Secondly, we analyzed long-term fishery landings records to detect whether changes in landings quantity and composition were related to the ctenophore invasion. Thirdly, we sampled catches of the lagoon fyke nets. This interdisciplinary approach overcame the weaknesses of single methodologies and allowed us to reconstruct the temporal phases of M. leidyi invasion in the Venice Lagoon. Moreover, our results indicate that the lagoon landings significantly declined with the blooms, paralleled by the increase of water temperature. Finally, we showed that the mechanical obstruction of the nets, caused by the massive ctenophore blooms, strongly impacts fishing activities. Our results are a first step in assessing the short and long-term impacts of this invasive species on lagoon ecosystems, including its socioeconomic consequences, whose better understanding is fundamental to inform mitigation and adaptation measures.

Spatial structuring of Mediterranean fisheries landings in relation to their seasonal and long-term fluctuations

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

Mean size at sexual maturity of female Cynoscion reticulatus along the Pacific coast off Mexico

Drums and croakers (Sciaenidae) are important to the species composition of coastal catches in the Gulf of California, Mexico. Among these species, the striped corvina (Cynoscion reticulatus) stands out because of its high fishery potential, high demand, and increased market value. The striped croaker has been under constant fishing pressure over the past 20 years. Still, there needs to be current biological information or reference points to allow the establishment of management measures for fisheries. The objective of the present study was to estimate the mean standard length at sexual maturity (SL50) of females using various models and to suggest a minimum catch size (MCS) for C. reticulatus off the southern coast of Sinaloa. Monthly samplings of coastal fishery landings were done from December 2020 to December 2021 on the south coast of Sinaloa. The SL50 was evaluated based on 3 candidate models (Gompertz, Lysack, and White) through a binomial approach. Confidence intervals for SL50 were estimated using likelihood profiles and contours, and Akaike’s information criterion (AIC) was used to select the best model. A total of 284 individuals were examined, of which 131 were used in calculations. White’s model was the most adequate; however, based on AIC weights, all 3 models performed similarly, and SL50 (24.48 cm; C.I. 95% 12.9–70 36.0 cm) was estimated as their average. As a management measure, we propose a precautionary MCS of 36 cm SL for C. reticulatus off southern Sinaloa.

Anchovy (Engraulis ringens) and Pacific sardine (Sardinops sagax) variability changes in northern Chile associated with the environment and inter species synchronicity: GARCH model with exogenous variable and hybrid Bayesian deep learning estimation approach

Small pelagic fish species, such as anchovy (Engraulis ringens) and Pacific sardine (Sardinops sagax), play a crucial role in marine ecosystems worldwide as they serve as an important food source for higher-order predators, such as seabirds, marine mammals, and larger fish species; also from their high productivity in terms of fishery landings, they help with maintaining food security. However, small pelagic populations are known for their variability, with fluctuations in their distribution and abundance influenced by interactions with environmental and human-related factors in different spatio-temporal scales. This study aims to investigate the variability in anchovy and sardine populations in northern Chile and their potential environmental drivers by using a class of models that address the changes in variability (i.e. variance) over time, namely Generalized autoregressive conditional heteroskedasticity (GARCH) models. In particular, this work considers a GARCH model that includes an additional term in the variance, that could help to better model the variability fluctuations of both anchovy and sardine, explained by environmental factors. Since there is no estimation procedures for those type of models, we propose a hybrid Approximate Bayesian Computation (ABC) procedure that involves the use of Deep Learning structures for estimating the parameters of the model and obtain posterior distributions. The results are two-fold: First, the proposal of a new time series model that better explain conditional variance with exogenous variables and a novel estimation procedure, and second, a novel approach for establishing explicit models that address the variability of small pelagic fisheries and their interaction with the environment.

Molecular identification of sharks from the genus Sphyrna (Elasmobranchii: Chondrichthyes) in Maranhão Coast (Brazil).

Sharks of the genus Sphyrna are under intense exploitation globally. In Brazil's northern coast, this genus represents a high proportion of fisheries landings and comprises four species. However, due to difficulty of specific identification when specimens are landed, most of the records are limited to the genus level. Here we analyzed the effectiveness of ITS2 (Internal Transcribed Spacer 2 of rDNA) fragment length protocol (Abercrombie et al., 2005) for identifying hammerhead shark species, comparing with the analysis of COI (Cytochrome oxidase subunit I) and ITS2 sequences. We evaluated samples of muscle tissue acquired in the main fishing ports of Maranhão: Carutapera, Raposa e Tutóia. Sampling was conducted between March 2017 to March 2018 and complemented with material deposited in collection (2015). COI results indicated the occurrence of endangered species which are prohibited to be landed. These include Sphyrna mokarran (67%), S. lewini (15%), S. tudes (3%), and S. tiburo (15%). For the ITS2 marker, we investigated the optimization of the protocol developed by Abercrombie (2005) for to improve the use in this geographical area througout design of a new primers.

A diagnosis of the artisanal fishery landings in the Colombian Caribbean coast by means of indicators

Landings of the artisanal fishery in the Colombian Caribbean from 2013 to 2021 were characterized by means of two indicators: the trophic level and the vulnerability to fishery landings. Indicators showed a statistically significant decreasing trend in vulnerability and trophic level, suggesting that the fishery is increasingly targeting species of low vulnerability and trophic level, thus moving down the food web. The overall pattern of indicators was not uniform in space. Incidence interaction of gears and species landed explained the trajectory of indicators at the scale of Departments. Fishing gears targeted different levels in the food web, with gillnets responsible for the bulk of landings. Compared to a previous study, the group of fish species supporting most of landings has changed towards species with lower vulnerability, i.e. resistant to fishing mortality due to their evolved life-history but still of predatory habits in general. A notable exception is Mugil incilis, a species with a low trophic level that has become third in importance of landings in the database.

An updated model of potential habitat for northern stock Pacific Sardine (Sardinops sagax) and its use for attributing survey observations and fishery landings

AbstractThree years after the 2015 collapse of the northern stock of Pacific Sardine that is predominantly located off the west coast of the United States, acoustic‐trawl (A‐T) surveys documented an increase in the presence and persistence of the southern stock off coastal Southern California. Then in 2020, the biomass of Sardine that was landed in Mexico and attributed to the northern stock exceeded the estimated biomass for the entire northern stock. To investigate if the landings were incorrectly classified, we revisit a model of northern‐stock potential habitat and the associated range of sea‐surface temperature (SST) used to apportion the A‐T survey data and monthly fishery landings to the two stocks, respectively. We update the probabilistic model of potential habitat with data on sardine‐egg presence and absence and concomitant satellite‐sensed SST and chlorophyll‐a concentration through 2019 and apply the new model to more accurately attribute the A‐T observations and fishery landings data to the northern or southern stock. The addition of recent data, with increased coverage in SSTs between 15°C and 17°C, improves the model accuracy and spatial precision of the stock attribution. The attribution accuracy is critically dependent on the temporal and spatial coincidence of the environmental and survey or landings data and should be corroborated with other characteristics indicative of biological isolation such as spatial separation, distinct spawning areas and seasons, and uncorrelated demographics.

Stable mean trophic level and decreasing fish size in Central Amazonian fishery landings

AbstractEvaluating trends in fisheries, especially data‐limited small‐scale fisheries, is challenging. We used fish landings to evaluate changes in composition of fish landings in rivers of the Central Amazon, from a discontinuous historical 28‐year series of landings from different data collection systems in main ports of the city of Manaus, the largest consumer market in the region. Annual mean trophic level (MTL), fishing‐in‐balance index (FiB), and mean landed size (MSL) were estimated. MTL did not decline, FiB was positive in most years, and MSL declined. Relative catches of certain fish species were replaced by others at a similar trophic level, but mean body size declined over time. We conclude that fishing in the Central Amazon is not sustainable and would benefit from better management strategies.

Gulls as Indicators of Environmental Changes in the North Atlantic: A Long-Term Study on Berlenga Island, Western Portugal

In recent decades, the breeding populations of the yellow-legged gull Larus michahellis (YLG) have increased significantly, primarily due to the increase in open refuse dumps and discards from fisheries. Portugal’s largest YLG breeding colony is located on Berlenga Island, where population numbers have been monitored since 1974. The population grew exponentially until 1994, prompting the implementation of population control measures, including culling adult birds and eggs. A long-term data base including number of breeding birds (since 1974), breeding parameters (since 2002), and trophic niches (using stable isotopes since 2011) of YLG breeding on Berlenga was related with oceanographic parameters, fish landings and quantity of urban waste. Trophic ecology showed strong relationships with oceanographic parameters (wNAO, Chl-a, and SST) and fisheries landings (the 10 most frequently consumed species by the YLG, traded at fish auctions in the main fishing harbour nearby). The results indicated significant relationships between reproductive performance and fisheries landings, particularly with demersal species that gulls primarily access through fisheries discards. However, population control measures played a pivotal role in stabilising and even reducing the population, despite sporadic events of poor oceanographic productivity in the past decade having a consistent impact on the reduction in breeding individuals.

Retrospective analysis of the pelagic ecosystem of the Western Mediterranean Sea: Drivers, changes and effects

In the Western Mediterranean Sea, forage fishes have changed in abundance, body condition, growth, reproduction, and distribution in the last decades. Different hypotheses have been proposed to explain these changes, including increase in fishing mortality; changes in environmental conditions affecting species fitness, and planktonic productivity and quality; recovery of top predators; and increase in competitors. We investigated the main drivers and changes of the pelagic ecosystem and their effects using an ecosystem-based modelling approach. Specifically, we (1) quantified the potential historical contribution of various drivers of change, (2) investigated changes in temporal trends and spatial distributions of main ecosystem components, and (3) identified ecological consequences of these changes in top predator and competitors, their fisheries and ecosystem traits during 2000–2020. We updated an established Ecopath food-web model representing the Spanish and French Mediterranean sub-areas (GSA06 and GSA07) in 2000 with recent available data. We applied the temporal dynamic Ecosim module, and tested historical time series of fishing effort, fishing mortality and environmental factors as potential drivers. Observed biomass and landings of key species were used to validate model projections. A spatial-temporal Ecospace model was developed to project species distribution changes. Results showed historical biomass and catch changes driven by a combination of high fishing pressure and environmental change (i.e. increase in temperature and salinity, and decline in primary productivity). Small pelagic fish showed significant temporal changes and predicted shifts in their distributions, following a latitudinal gradient. Predators and competitors showed changes as well, displaying heterogeneous spatial patterns, while fisheries landings declined. Overall, results matched observations (e.g., decline of sardine, fluctuations of anchovy and increases in bluefin tuna) and illustrated the need to complement traditional assessments with integrative frameworks to move towards an ecosystem-based approach in the Mediterranean. They also highlighted important knowledge gaps to guide future research in the region.

Portraying Trawl Fishery in Albanian Waters: Case Study from the Sarandë Area (Southern Albania)

Abstract The current study provides valuable insight into the trawl fishery operating in southern Albanian waters via an integrated approach based on high-frequency onboard monitoring trawl vessels and on-site interviews with local fishers. Multivariate analyses of the composition of species landings or economic revenue revealed groups that, depending on the group, were distinguished by improved fisheries landings and economic efficiency. The majority of the catch consisted of a variety of demersal and small- and medium-sized pelagic species, confirming the Adriatic Sea's multispecies nature. Target species identified in terms of catches and revenue imply a systematic tactic over a long period of time, and incidental catches are equally important in terms of overall group similarity. The identification of target species groups may be useful in assessing the current sampling stratification schemes.

Ecological Assessment of Fishery Communities in an Otter-Trawl-Restricted, Semi-Enclosed Gulf in Greece

A fishery-independent survey with a commercial bottom otter trawl was conducted in the Pagasitikos Gulf, a semi-enclosed, trawl-restricted gulf in Greece. The study aimed to ecologically assess the fishery communities that are experiencing a decline in fishery landings. Twelve hauls of 30 min duration each were conducted in the eastern, western, and central parts of the gulf at depths between 62 and 97 m. In total, 57 species were captured, with the highest species number recorded in the west (35 species), followed by the center (32 species) and east (29 species). The highest numerical abundance was recorded at the center, followed by the east and west, with an opposing trend exhibited for biomass; however, GLM detected no significant spatial differences (in area or depth) or interaction. Ecological indices exhibited significantly lower values in the west–east area comparison. Linear Discriminant Analysis, mMDS, and hierarchical clustering indicated the presence of two main groups (east and west), with PERMANOVA showing a significant difference in the demersal communities among the identified groups. The results indicated moderately disturbed demersal communities and an increasing level of disturbance from east to west. Considering the economic value of Pagasitikos to the local fishing community, additional fishery management measures are deemed necessary to protect the fishery resources and mitigate the potential risks of overexploitation.