Fisheries Development Research Articles

Population aspects of Crassostrea sp. in a protected mangrove estuary: perspectives for artisanal fishing management

ABSTRACT The mangrove oyster (Crassostrea) is one of the most common bivalves found on the Brazilian coast, widely used in artisanal fisheries. Oysters are dioecious with external reproduction, typically found in estuarine environments. The present study aimed to identify the population aspects of Crassostrea in different fishing locations in northeastern Brazil. The study area was the Acaú-Goiana Extractive Reserve, a protected area focused on the development of artisanal fisheries. Oysters were collected during low tide at three sampling points, where their removal from mangrove roots was carried out, during May, July, September, November 2021, and January and March 2022. In the laboratory, biometric measurements were conducted, and for the months of May and November 2021 histological preparations to study the reproductive cells. Biometric measurements were significantly higher in the dry season at all sampling points. The sex ratio was M = 0.38, F = 0.62, for May, and M = 0.30, F = 0.69, for November. The biometric and reproductive data obtained can support the development of management strategies, including a rotation plan between collection sites and the establishment of a minimum size for fishing. Here we recommend a minimum size of 20 mm shell length (SL) or larger for fishing.

THE ROLE OF FISHING PORTS IN THE SUSTAINABLE BLUE ECONOMY

Fisheries and aquaculture play an important economic, environmental and social role. The development of fisheries and aquaculture depends on many factors, including adequately equipped ports and landing sites. The aim of this paper is to highlight the roleof fishing ports in the sustainable blue economy. Fishing ports support the sustainable development of fisheries and aquaculture by promoting best practises for environmental protection, maintaining food quality, creating fair prices, supporting workers' rights, integrating local communities and ports, and more. The Food and Aquaculture (FAO)Blue Ports Initiative aims to strengthen the role of ports as drivers of sustainable development in coastal communities and promote the achievement of several key Sustainable Development Goals (SDGs), including SDG 1 (No Poverty), SDG 2 (Zero Hunger), SDG3 (Good Health and Well-being), SDG 5 (Gender Equality), and SDG 14 (Life Below Water). However, ports are also encouraged to adopt a blue economy approach to management to achieve long-term benefits for local communities. Port management, in collaboration with scientists, policy makers, the private sector, and civil society, should focus on inclusivity, competitiveness, greening, and process efficiency, and support collaborative actions to improve the quality of life of local communities. KEYWORDS:fishery and aquaculture; ports; sustainability; blue economy; marine environment

Analyzing fishery data and exploring the resource status of Antarctic krill based on its environmental dependence

AbstractAntarctic krill Euphausia superba is a key species in the Southern Ocean ecosystem and has important ecological value. It is also one of the main fishery resources in the Southern Ocean with high economic value. In recent years, with the development of krill fishery and rapid climate change, the conservation and management of krill resources have faced unprecedented challenges. The krill resource is different from the general fishery resources. Due to the krill schooling characteristics, fishery data has some advantages over scientific survey data. Reviewing and analyzing the krill fishery data is necessary. Therefore, in this study, four fishery resource indices (FRIs) were calculated based on Antarctic krill fishery data, and based on the environmental dependence of Antarctic krill, the FRI with the strongest environmental dependence was screened by using the Gradient Forest Model, and the step changes of the FRI with strongest environmental dependence was examined by using the sequential t‐test analyses of regime shifts (STARS). The generalized additive model (GAM) to analyze the correlation between the FRI with the strongest environmental dependence and the main environmental factors, and then explore the resource status of Antarctic krill in the study area. The model results showed that the “FRI_hual” had the strongest environmental dependence and was a better indicator of the status of the Antarctic krill in the study area than the others. In the 2009–2010 year, “FRI_hual” had an obvious regime shift. The interaction of environmental factors “ice_area_2” and “SSH_1” has a great impact on “FRI_hual”. Methods used and results obtained in the study can provide new ideas and a scientific reference for future work, including integrated stock assessment of krill and krill resource monitoring, conservation, and management based on the ecosystem.

Optimal harvest for predator–prey fishery models with variable price and marine protected area

In this paper, we propose a predator–prey fishery model with prey harvesting, variable price and marine protected area. We assume the price changes faster than other processes such as population growth and predation, and get a slow fast Ordinary Differential Equation (ODE) system. A simplified three-dimensional model is obtained by using approximate aggregation methods. The results show that there are two main scenarios, one is the depletion of fish stocks due to overfishing by fishermen, which is called a “catastrophic” equilibrium; and the other is a stable and sustainable fishery equilibrium. In order to avoid the extinction of fish, we consider establishing marine protected area (MPA) near fishing areas where fishermen only catch the prey. The results of the study provide the conditions for the establishment of MPA, allowing us to avoid the extinction of prey populations and establish sustainable fisheries. As another possibility, we consider increasing taxes to discourage overfishing by fishermen. In addition, when the tax revenue increases, the optimal harvest strategy is obtained. The optimal policy ensures the sustainable development of fisheries and maximizes the interests of fishermen.

Analysis of influencing factors of carbon emissions from China’s marine fishery energy consumption under different development scenarios

China’s rapid economic development has consumed a large amount of energy, causing serious environmental pollution problems and contributing to global warming. This paper calculates the carbon emissions of the fishery sector and uses Random Forest (RF) for the first time to analyze the influencing factors of future carbon emissions. The results of the study show that increasing carbon sinks dominate the reduction of carbon emissions in the fisheries sector. Carbon sinks will continue to dominate emission reductions in the fisheries sector if positive mitigation measures are taken. Continuing the current pattern of fisheries development, the fishery population has a significant impact on future carbon emissions. Per capita incomes under a crude economic model will inhibit carbon emission reductions. The research results can provide guidance for the development of fishery low carbon economy and the formulation of emission reduction policies.

Gendered perception and factors influencing the choice of innovation in the fisheries sector: A case of southern Ghana

This study seeks to examine the perception of fish workers about fisheries innovation and factors influencing the choice of innovation in Ghana's Greater Accra and Central regions. The study uses weighted mean index and multinomial logit model to analyze the data on 230 fish workforces. The results reveal that fish workforces perceive the likelihood of men innovating to be more relative to women due to the difference in the nature of fish activity undertaken by men and women. Factors such as age, gender, education, marital status, saving, credit access, perceived usefulness, association membership and location significantly affect the choice of innovation techniques. Specifically, female fish workers were found to be less likely to use entrepreneurial innovation but more likely to choose demand/supply driven innovation techniques. The paper recommends that the Ministry of Fisheries and Aquaculture Development (MoFAD) and its Development partners organize training sessions on gender dimensions to reiterate the importance of adopting fisheries innovation for enhanced productivity. Also, fish workers especially women should be encouraged to join groups and develop a culture of savings to position them for innovation adoption. With growing interest in innovative initiatives within the fisheries sector that facilitate fishing activities, this study is one of the first to explore innovation adoption from a gendered perspective in Ghana.

Prospective Analysis of the Role of Actors in the Formulation Strategy for Fisheries Development in Purworejo Regency

Prospective Analysis of the Role of Actors in the Formulation Strategy for Fisheries Development in Purworejo Regency

Fisheries local action groups, small‐scale fisheries and territorial development

AbstractIn comparison to the wealth of critical evaluation of LEADER (i.e., Liaison entre actions de développement de l'économie rurale), there has been no consolidated attempt to reflect on the contribution of Fisheries Local Action Groups (FLAGs), now entering their third EU programming period. Set up in the image of LEADER, and a novel governance instrument within the Common Fisheries Policy (CFP), FLAGs aim to activate local responses that build resilience and adaptability within the fisheries sector and wider communities. In addition to introducing the accompanying articles that make up this special issue of Sociologia Ruralis, our article gives an account of the emergence of community‐led local development (CLLD) in fisheries and the attributes that have characterised the application of the LEADER approach within a fisheries‐territorial development context. In many cases, FLAGs have led to improved relationships between the small‐scale fishing sector and wider local social and economic networks, helping the sector reimagine its role within local economies. Yet outcomes vary as the FLAG approach has been applied across different cultural and institutional settings. There are indications that the system is becoming enveloped by wider priorities of coastal development and blue growth. Yet FLAGs may well provide a successful test case for widening participation in the CFP and upscaling integration of the fishing industry within local and regional economies. For CLLD in general, they are a reminder of the value of a differentiated CLLD approach tailored to different sectoral‐territorial contexts.

Learning from the history of red shrimp fisheries in the Mediterranean to improve sustainability of deep-water bottom trawling

Abstract As deep-water red shrimp (DWRS) trawl fisheries gain importance in the Mediterranean, their impact on fragile deep-sea ecosystems requires careful management. We reviewed the historical development of DWRS fisheries in the Mediterranean to propose a harvest strategy that would enhance fishery sustainability, while preserving habitat and community integrity. We considered two representative typologies of DWRS fisheries: a domestic fleet operating within the Italian territorial waters of the Ligurian Sea, and a distant fleet operating mostly in international waters of the central-eastern Mediterranean and sharing shrimp stocks with non-European countries. Our proposed management approach is based on three main harvesting measures: (i) preventing the uncontrolled growth in number of trawlers, (ii) adopting a catch control regime, and (iii) identifying a network of deep-water areas designated alternately for fishing and conservation purposes. As with fisheries in other regions, new fishing grounds should be explored using “encounter protocols” to avoid areas hosting species indicators of Vulnerable Marine Ecosystems. Additionally, empirical indicators such as catch rate thresholds derived from fishers’ experience, could be used to move from one fishing ground to another to avoid local depletion of DWRS abundance and a decrease in fishery profitability.

Evaluating the Challenges Facing Small-Scale Sugarcane Farmers (Sugarcane Outgrowers) In Zimbabwe: A Case Study of Chiredzi District in Masvingo Province, Zimbabwe

The study was based on the evaluation of the challenges facing small-scale sugarcane farmers (sugarcane outgrowers) in Zimbabwe and focusing on Chiredzi District. Consequently, the research used phenomenological philosophy to study this phenomenon and the sample was made of 50 persons comprising of 20 sugarcane outgrowers, 5 Ministry of Lands, Agriculture, Fisheries, Water and Rural Development officials, 5 Ministry of Women Affairs, Community, Small and Medium Enterprises, 5 Agritex, 5 Village heads and 10 spouses. Accordingly, the findings from the study show that small-scale sugarcane farmers in Chiredzi District are facing a myriad of challenges and that the government should intervene in order to save the industry. Likewise, microfinance institutions should help sugarcane outgrowers with the much-needed funds for their day-to-day operations. Thus, it was suggested that Ministry of Lands, Agriculture, Fisheries, Water and Rural Development officials and the Ministry of Women Affairs, Community, Small and Medium Enterprises should help sugarcane outgrowers with establishing a workable relationship with Tongaat as the current one is unhinged in favour of Tongaat Hullets. Similarly, sugarcane outgrowers are playing a vital role in developing Zimbabwe economically. Therefore, should be equipped with the much need entrepreneurship prerequisite skills sets though up-to-date trainings in order to equip sugarcane outgrowers with extant and suave entrepreneurial skills in order for them to increase production and meet the expectations of their miller through capacity building.

Mapping the potential spatial distribution for offshore finfish aquaculture in China under climate change

Offshore aquaculture plays an important role in alleviating the pressure of coastal aquaculture and promoting the sustainable development of fisheries. And changes in ocean conditions caused by climate change will have a huge impact on mariculture. Considering the conditions of climate change, this study took the main mariculture fishes in China as the research object, used a species distribution model (SDM) to predict the potential mariculture areas of each fish under the current and different future (2040–2050) climate scenarios, divided the mariculture areas into three potential levels by natural breaks classification method, and calculated the area of different levels potential areas of each fish through the grid number and grid unit area. Additionally, this paper compares the potential area variation of different fishes under different climate scenarios. The results indicate that: (1)In the current climate, the potential area of Yellowtail kingfish(Seriola lalandi) is the largest among seven fishes, estimated at 1,288,500 km2. And the number of varieties suitable for aquaculture in the East China Sea and the South China Sea is more than that in the Bohai and Yellow Seas. (2)Compared with the high potential area of current and future climate scenarios, Large yellow croaker(Larimichthys crocea) has the largest increase, Yellowtail kingfish(Seriola lalandi) decreases under all four future climate scenarios, and both Cobia(Rachycentron canadum) and Allied Kingfish(Seriola dumerili) has small changes. (3)In the future climate scenarios, the number of species potentially suitable for culturing increases significantly in the Bohai and Yellow Sea area, and in the South China Sea, the suitable areas for cultured Large yellow croaker(Larimichthys crocea), gold pompanos(Trachinotus ovatus), Cobia(Rachycentron canadum) and Allied Kingfish(Seriola dumerili) decrease significantly. Overall, the potential areas of each fish show a northward trend.

Effective “off-on” switch for fertility control in female zebrafish

The implementation of a controllable sterility strategy is crucial for the commercialization of precise trait improvements in farmed fish using genome editing and sustainable development of fisheries. Our previous research has demonstrated that females deficient in pituitary gonadotropin luteinizing hormone β-subunit (lhβ) or gonadal steroidogenesis gene steroidogenic acute regulatory protein (star) exhibit sterility due to impaired oocyte maturation and ovulation. Nevertheless, the effective restoration of fertility in lhβ- or star-deficient females remains unsolved. This study has discovered that the administration of exogenous 17α,20β-dihydroxy-4-pregnen-3-one (DHP) at 100 and 300 μg/L for 6 h (from 02:00 to 08:00 a.m.) effectively restores the fertility of lhβ- or star-deficient females. Fertilized eggs from these mutant females can be raised without noticeable developmental defects for up to 3 weeks post-fertilization (wpf) compared to the wild-type (WT) control zebrafish. The increased expression levels of adamts9 and adam8b in lhβ- or star-deficient zebrafish females treated with DHP demonstrate a positive correlation with oocyte maturation and ovulation restoration. In contrast, exogenous DHP administration did not rescue the sterility phenotype observed in progesterone receptor (pgr)-deficient females. Building on our recent success in generating an all-female carp population through cytochrome P450, family 17, subfamily A, polypeptide 1 (cyp17a1)-depletion, our research presents a promising and effective strategy for an “off-on” switch for managing fertility in genome-edited cyprinids. The strategy would offer practical guidance and theoretical justification for developing “controllable fertility” in all-female fish, which would support the sustainable development of fisheries by promoting the use of novel biotechnologies in aquaculture in an eco-friendly manner.

Maw money, maw problems: A lucrative fish maw fishery in Papua New Guinea highlights a global conservation issue driven by Chinese cultural demand

AbstractFish maw (teleost swim bladder) is a dried seafood product valued highly by Chinese cultures in East Asia, though global supply chains are poorly understood. Here, we describe the rapid development of a fish maw fishery in a low‐income nation to illustrate how globalization can affect sustainability. In Papua New Guinea (PNG), fish maw developed into a fishery valued at ∼$831,000 USD annually between 2014–2018. Its development has been driven by Asian expatriates, who provide market access and fishing gear to local communities. The highest valued local species, scaly croaker Nibea squamosa, has a maximum value of $15,615 USD kg−1 (dried) at first‐point‐of‐sale, potentially the highest first‐point‐of‐sale fish maw product globally. Its value has led to high incidental catch rates of threatened species in an area that is a globally significant conservation stronghold. International trade databases need to recognize fish maw as a high value and globally traded product and consider a specific fish maw commodity code to assist nations in identifying emerging fish maw fisheries. Additionally, the Convention on the International Trade of Endangered Species of Flora and Fauna (CITES) could assist in protecting vulnerable fish maw species and facilitate management practices for incidentally caught threatened species.

State of resources and fishery of commercial Seaweeds and Seagrasses in the Seas of Russia in 2000–2020

The aim: Stock assessment of commercial algae and seagrasses in the sea waters of Russian Federation and their fishery in 2000–2020.Method: The present article is based on original and statistical data obtained in 2000–2020 in accordance with standard methods of fisheries research.Novelty: The analysis has revealed the present status of commercial algae and seagrasses resources in the seawaters of Russian Federation as well as the reasons for low exploitation rates of these resources.Result: Algae and seagrasses resources in the seawaters of Russian Federation have hardly changed during last 20 years and remain stable. Algae harvesting is relatively well developed only in White Sea and Japan Sea. Total biomass of commercial algae and seagrasses resources in the sea waters of Russian Federation estimates at 1.6 million tons, and annual recommended catch — at 250 thousand tons.Practical significance: The results of present analysis have reveal modern trends of algae fishery development and allow to elaborate science-based approaches for conservation and sustainable management of these resources.

Russian fisheries in 2000–2020

Purpose of the work: analysis of the development of fisheries development in Russia in the first two decades of the 21st century, assessment of stock state and catches of fish resources, and identification of major factors of influence on these resources and fisheries. Methods used: the main source of information on the production in Russian fisheries was annual data on catches of fish and other aquatic biological resources and data on aquaculture production — Form No. 1-P (fish). Сatches and yields of fish resources were analyzed based on the operative reporting of enterprises and data of the industry monitoring system. For access and initial processing, the FMS analyst software was used.Novelty: an analysis of the regulatory and legal framework development is presented, materials from Russian fisheries for 2000–2020 are summarized and analyzed.Practical significance: the development of any type of economic activity is a continuous, but heterogeneous process, with periods of growth and decline of varying duration. Fishery is no exception. Throughout its history, the industrial fisheries in Russia have gone through a series of stages associated with changes in fisheries technology and evolution of fishing vessel design. The development of industrial fisheries was also related to such objective conditions as long-term climate changes, which influenced the state of fisheries resources.

A Three-Dimensional Spatial Interpolation Method and Its Application to the Analysis of Oxygen Deficit in the Bohai Sea in Summer

Dissolved oxygen (DO) plays a pivotal role in sustaining marine ecosystems. The Bohai Sea in China is a semi-enclosed sea, and oxygen-deficit events occur from time to time due to human activities. At present, there is a notable absence of any convenient and precise method for obtaining three-dimensional spatial data on DO, and the exploration of the physical mechanisms influencing oxygen deficit remains incomplete. This investigation uses the linear radial basis function (RBF-Linear) fitting method to conduct three-dimensional spatial interpolation for DO, which demonstrates minimal inaccuracy. Then, the RBF-Linear fitting method is utilized to collect a comprehensive three-dimensional spatial dataset encompassing temperature, salinity, and DO in the Bohai Sea in August from 2016 to 2018. The results indicate discernible interannual variations in the extent, area, and distribution of oxygen deficiency during summer in the Bohai Sea. Mechanism analysis reveals that intense precipitation episodes and an increase in wind stress curl exacerbate oxygen depletion. Additionally, the degree, location, and area of the two oxygen-deficit cores (off the Yellow River Estuary and off the Qinhuangdao) in the Bohai Sea are influenced by several factors, including current velocity, direction, local circulation position, and net horizontal transport rate. Furthermore, the study suggests that oxygen deficiency in the Bohai Sea region is currently in its early stages, with a limited degree of injury and a restricted range of influence. The use of a three-dimensional spatial interpolation method to create a complete DO field in three-dimensional space simplifies the research challenges associated with marine oxygen deficit. Moreover, this study holds particular significance for guiding the development of marine fisheries.

Russian fishing in the Atlantic and Southeastern Pacific Oceans in 2000–2020

The aim: to analyze the development of domestic fisheries in the Atlantic and Southeastern Pacific Oceans in 2000–2020, to assess the state of stocks and catch of the most important types of aquatic biological resources.Methods: conducting trawl-a coustic, ichthyological and hydrological accounting studies in 2000–2020. Analysis of domestic and foreign literature.Novelty: the article presents an up-to-date analysis of the development of Russian fishing, the intensity of fishing and the state of exploited stocks of commercial fish species.Results: Information is provided on the status and dynamics of stocks and catch of commercial aquatic organisms in various areas of the Atlantic and southeastern Pacific Ocean. During the period under review, the highest biomass of stocks and catch are observed in pelagic fish species in the North-East Atlantic. The state of stocks and catch of bottom fish species in the far North Atlantic regions are at an average or low level. In general, in the first two decades of the XXI century, favorable conditions for conducting domestic fishing were noted. For the Central-Eastern Atlantic area (EEZ of Morocco and Mauritania), information is provided on the status of the main commercial fish stocks. Particular attention was paid to the possibility of resuming the domestic tuna and mackerel fishery in the south-e astern Pacific Ocean.Practical significance: the results of the analysis can be used to make management decisions on the development and regulation of fishing.

Analysis of the Current Situation and Development Strategies of Marine Fisheries in Jiangmen City

Based on the statistical data of marine fisheries in Jiangmen City in the past three years, this paper analyzes the development status and trend of marine fisheries. By combining the information obtained from enterprise research, it deeply analyzes the main problems existing in the development of marine fisheries in Jiangmen City and puts forward corresponding optimization countermeasures, which provide suggestions for promoting the high-quality development of marine fisheries in Jiangmen City.

Diet Composition and Feeding Habits of Fish Larvae of Five Species in the Burullus Lake, Egypt

Feeding habits of fish larvae were analysed in a comparative study of five species (Oreochromis niloticus, O. aureus, Tilapia zilli, Mugil cephalus and Liza ramada) from the Burullus Lake. We investigated the potential influence of larvae size on their feeding and looked for common patterns in larval prey preference. Gut contents of a total of 1068 larvae were examined. The feeding habits of the examined larvae shared some characteristics. As larvae of the five species grew, the preferred prey size and the number and diversity of prey in the gut increased. On the other hand, larval feeding also differed in several aspects, especially differences in the composition of preferred prey items. For Cichlidae larvae, the dominant prey was the rotifer Brachionus plicatilis followed by copepodite stages. For M. cephalus larvae, the copepods Paracalanus sp and Acartia sp were the most important diets, while for L. ramada, decapod larvae were the most important. The Mugilidae larvae consumed significantly larger prey than the cichlid larvae, which could be related to their morphology, especially the mouth size. Ivlev’s selectivity index calculated for larvae showed positive selection for particular prey. In all the species, copepods were the most selected, particularly for Mugillidae larvae, but for Cichlidae larvae, the rotifer Brachionus competed with copepods as a selected prey. This dietary study of fish larvae of these important species is essential for the development of fisheries and can be implemented in further related studies of other areas.

Constraint perceived by beneficiaries in adoption of fisheries development programmes in Vidarbha region of Maharashtra

Constraint perceived by beneficiaries in adoption of fisheries development programmes in Vidarbha region of Maharashtra