Search

This study presents an overview of bivalve assemblages in Bahia Magdalena (BM, México) and the possible impact of environmental variability on these populations, constantly stressed by fishing. This lagoon is responsible for a high proportion of harvest of regional bivalves. First, we list the bivalve species reported in public biogeographic databases. Based on eight commercially exploited species, we described the composition of the bivalve assemblage and its biological characteristics, the history of fishery, and environmental variability in the marine area adjacent to the lagoon (1970–2019) and the habitat of bivalves (2002–2020). Sources of data were public databases and published literature. The enlisted species (n = 184) belong to six orders, and most are small and infaunal, but the structure of the assemblage is unknown. The fisheries began at different times and focused on the most valuable resources. Almost all harvest of bivalves had wide variations because of intensive fishing and a weak regulation frame. After 2015, the main resources were the Pacific wing-oyster (a new resource since 2017) and the geoduck clam due to the declining abundance of other resources (e.g., pen shells, Pacific calico scallop). There was a warming trend in the region since the 1970's, but the strongest El Niño-Southern Oscillation (ENSO) phases caused the most notable changes before 2013; after that year, a combination of large-scale phenomena increased the temperature significantly. The trend of chlorophyll-a abundance negatively correlated with temperature, but there was an almost constant supply of particulate organic matter in the interior of Bahia Magdalena (BM). After 2015, the quality of lagoon water gradually deteriorated, and in 2017 and 2019, harmful algal blooms developed, but the impact was not fully assessed. The challenges faced by the fishery are multiple (institutional weakness and regional warming); however, permanent monitoring programs of environmental conditions and critical biological variables should be implemented to design scenarios that allow fishery sustainability.

The Loreto Bay National Park, a multi-use marine protected area in the Gulf of California, Mexico, has potential as a combined conservation and fishery management tool. The main objective of the park is to promote the sustainable use of its marine resources for the benefit of the local community. Small-scale fishers living and working within the park boundaries see the marine protected area as having benefits for tourism in the region, but do not see a benefit reflected in a recovery of marine resources that can maintain the fishery stock. This paper evaluates the validity of this perception and whether or not the park has been successful in meeting this objective.

This paper highlights three major concerns pertaining to legal frameworks aimed at elimination of IUU fishing across the globe. First, gaps persist even among developed countries and there is room for improvement at national level and scope for cross-country exchange of experiences. Second, to avoid undermining its own efforts directed towards sustainable exploitation of marine resources, all states should be interested in supporting their counterparts in closing regulatory gaps in fisheries regulations. International collaboration can result in improved management of fishery resources in developing countries. Third, the adoption of best practices at a national level does not necessarily go hand in hand with introducing state-of-the-art measures at the regional level. States with well-developed national legal frameworks have an opportunity to have a positive impact on the development of conservation and management measures at the regional level, but the move towards best practice is slow. [ABSTRACT FROM AUTHOR]

Ecosystem models can be used as fisheries management tools in the context of a holistic approach and view of assessing the status of aquatic ecosystems and proposing plans of action. The Ecopath with Ecosim modeling suite has been widely used to describe exploited marine systems and perform simulations over time. Pagasitikos Gulf is a shallow semi-enclosed gulf in the western coast of the central Aegean Sea that is characterized as semi-protected, with a bottom trawling ban in force since 1966. In this study, an Ecopath model was constructed including 31 functional groups (FGs) of organisms of lower to higher trophic levels, while Ecosim temporal simulations were run for 18 years (2008–2025), including the calibration period (2008–2017). An overall decrease in biomass and catch of the studied marine resources was observed by the end of the simulation period, due to environmental factors as well as fisheries exploitation. To examine the effect of fishing, three different scenarios were investigated, all aiming toward fishing effort reduction by 10, 30, and 50% compared to the initial business-as-usual scenario, applied to both fleets operating in the area (purse seiners and small-scale). All examined scenarios led to higher total biomass compared to the basic Ecosim simulation (the higher the reduction in fishing effort, the higher the increase in biomass), while catches were significantly lower in all cases as a result of less fishing. The most profound biomass increase with reduced fishing effort was observed in other larger pelagics, anchovy, anglerfish, sharks and rays, mackerels, hake and other gadiforms. In conclusion, reducing the exploitation levels of the ecosystem is a key factor that contributes to rebuilding of marine resources.

The status of Atlantic salmon, Salmo salar L., over the last decades has been of concern across its entire distribution area. Its anadromous nature exposes the species to human pressures in both freshwater and marine environments, and over long periods, thus exacerbating its decline. Given its value within the food industry, the recreational angling community as well as culturally, the status of Atlantic salmon is regarded as a matter of national and international conservation interest, providing great incentive for its management. The literature currently lacks specific examples of successful and unsuccessful management strategies and practices for Atlantic salmon populations at a broader scale. To address this, the present article describes how the multi‐faceted management approach taken for Danish Atlantic salmon, which included changes in legislation, stocking practices, habitat restoration, population genetics and barrier removals, successfully rehabilitated salmon populations in four major Danish rivers. Specific recommendations are provided for the successful management of Atlantic salmon elsewhere. [ABSTRACT FROM AUTHOR]

• Stage structured mortality rates result from fish life history and human behavior. • Large females in sexually dimorphic species are favored by release of large fish. • Relaxed regulations may result in lower adult female mortality rates via increased male harvest. • Integrating life history and human behavior into models provides insight for modern conservation. Human behavior shapes modern ecosystems but is difficult to parse into parameters for ecological models. We used Bayesian models of human behavior, a stage-structured population model, and a novel mortality integration approach to ask how human decisions affect animal population dynamics and conservation outcomes in the context of recreational fishing. Walleye (Sander vitreus) are a broadcast-spawning freshwater fish with large, slow-maturing females and small, fast-maturing males. We observed that simpler and less restrictive fishing regulations outperformed more complex and stricter regulations at conserving equilibrium adult female abundance and overall population abundance while still facilitating large harvests. This outcome was possible because angler behavior within the least restrictive regulation concentrated harvest on juveniles and adult males. Our findings indicate that, counter to intuitive expectations, moderate regulations can acheive conservation objectives when we account for the interaction of regulatory policy, human behavior, and animal life history. We suggest that integrating models of human behavior with models of animal life history and population dynamics will provide essential insights for conservation in ecosystems increasingly shaped by human decisions. [ABSTRACT FROM AUTHOR]

Fishing activity is conditioned by diverse factors that determine and limit the capacity of fishermen to decide on their level of production (i.e., the fisheries output is determined exogenously). In the context of the input-output analysis, models have been developed that permit the assessment of socioeconomic impacts of an activity, but almost always from a perspective where demand is the driving force of the economy. Procedures have recently been developed to measure impacts in which both the existence of sectors subject to exogenous supply shocks and the existence of forward linkages with other sectors of the same economy are considered. The objective of this study is the application of this new methodology for the analysis of a specific case: fishing activity in Galicia (NW Spain). The socioeconomic impacts linked to the determination of annual fishing quotas by species for major fleet segments managed by European Union are quantified. This procedure is should be potentially be very useful as a fishing management tool. It provides more accurate estimations of the possible socioeconomic impacts of catch limitations and gives detailed information on the sectoral and spatial distribution of these impacts on the economy. [ABSTRACT FROM AUTHOR]

Illegal, Unreported and Unregulated (IUU) fishing is recognised as a global environmental, economic, and social problem, taking place in all kinds of fisheries. Preventing it is however difficult and there is a continuous need to expand the knowledge base on how the issue can be addressed. In this article we study fisheries crime from an environmental criminology approach by conducting a crime script analyses to describe the organisational structure of unreported fishing in a well-regulated fishery. The approach gives detailed insights into the different steps in the crime commission process in the Norwegian coastal cod fisheries. The crime script technique is expanded to also include an analysis of the regulatory framework designed to prevent illegal fishing activities. The main MCS mechanisms to prevent illegalities are present but the diversity in the industry makes the implementation of universal prevention mechanisms difficult. The analysis highlights the fisher-buyer dialogue and interactions prior to misreporting as a core aspect to the organisation of the violations, and difficult to regulate. When linking regulations and guardianship to different steps of the crime we discuss the identified vulnerabilities in the resource control system and present some possible intervention points and prevention mechanisms to be considered by policymakers. [ABSTRACT FROM AUTHOR]

How do technologies of power make the world governable? The understanding of how management techniques create governability remains rather poor. In this article, I analyse how spatial regulation in Norwegian fisheries direct human behaviour towards scientific, political, and administrative objectives. Like other fisheries' regulations, they contribute to governmentalisation and governability, and this article illustrate how this happens. Governance aims towards specific outcomes, but in the attempt to make the world governable, the governing and those who are governed are changed and new social orders may be the result. Thus, governing instruments are not only instruments for the direction of behaviour, but also instruments for social change. [ABSTRACT FROM AUTHOR]

A feasibility study was conducted on the impacts of the new Common Fisheries Policy (CFP) rules requiring catches in regulated fisheries to be landed and counted against quotas of each Member State - the landing obligation (LO), and that catch of species subject to the LO below a minimum conservation reference size (MCRS) be restricted to purposes other than direct human consumption. The aim was to estimate the level of discarded fish likely to be covered by the new rules, the impact of the rules on EU fisheries and the regulatory challenges and responses to them. Data from EU's Scientific, Technical and Economic Committee on Fisheries (STECF) database were analysed to estimate the volume of unwanted catches produced by EU fisheries. Views were sought from policy officials and fisheries scientists through a questionnaire on the implications of the LO and the control of fisheries across Member States, and the potential adjustments that might be needed. Findings show that 11% (44,000 t) of the total catches of EU countries from which data were available are of fish under MCRS. The species with the highest volume of undersized discards associated with the lowest quota, which would potentially restrict the fishing opportunities for other quota species (i.e. choke species), are plaice and haddock with 18,000 and 14,000 t of undersized fish respectively, followed by whiting and cod with 5000 and 6000 t of undersized fish respectively. Discards data shows that the Netherlands, United Kingdom, France and Belgium will be most affected by landings for non-human markets. Findings also show that existing infrastructure at landing ports in all Member States is limited because there are currently limited facilities in place to handle animal by-products produced by the catching sector. Policy officials maintained that while they could support the fishing industry through funding programmes, it is the responsibility of fishers to ensure they have the right infrastructure to handle unwanted catches. The expectation is that the LO combined with the restriction to non-human consumption purposes will encourage fishers to internalise the costs of catching unwanted fish and motivate them to avoid unwanted catch. This will be realised if sufficient flexibility is given to fishers to find their own solutions to reducing unwanted catches. It is concluded that gear technology measures exist to enable the regulated fisheries to increase gear selectivity. [ABSTRACT FROM AUTHOR]

Illegal, Unreported and Unregulated (IUU) fishing is one of the serious threats for the sustainable fishing in the entire Mediterranean Sea. Due to IUU fishing, ghost fishing, by-catch, depletion of the fishing stocks, destruction of the benthic ecosystem has been reported. This issue has several social, economic and legal dimensions. Most of the coastal states have IUU fishing practices in the Mediterranean. However, most of them do not necessary record by-catch, ghost fishing and data related fisheries crimes. Purseseine, trawl and driftnets were most common fishing gears for IUU fishing. Bluefin tuna, swordfish, among benthic species shrimps are the most common target species in the coastal states of the Mediterranean Sea. Most of the by-catch species were cetaceans, sea turtles, seabirds and sharks. Concerted actions and international cooperation are essential to halt IUU fishing. Zero tolerance should be the main concept against IUU fishing. A common black list of IUU fishermen and fishing vessels should be prepared and shared by the riparian states. National fleet management plans and Monitoring, Control and Surveillance (MCS) System should be encouraged by riparian states and GFCM in the entire basin. [ABSTRACT FROM AUTHOR]

Increasing the chances that resource users engage in and comply with management regulations is a continual problem for many conservation initiatives globally. This is particularly common when resource users perceive more personal costs than benefits from specific management actions. Analysis of interviews with managers and fishers from 22 landing sites along the coast of Kenya indicated how key stakeholders perceived the scale of benefits and costs from different management strategies. Potential underlying causes of divergent perceptions towards different management tools were evaluated, including marine protected areas, no-take fisheries closures, gear use, minimum size of fish caught and species restrictions. The analysis identified three distinct opinion groups: (1) a group of nine landing sites that scaled their preference for most management restrictions neutral to low, with exceptions for minimum sizes of captured fish and gear restrictions; (2) a group of eight landing sites that scaled their preference for the above and species restrictions and closed season higher, and were more neutral about closures and marine protected areas; and (3) a group containing four landing sites and the managers’ offices that rated their preference for the above and closed areas and marine protected areas as high. Logistic regression was used to examine whether these groups differed in wealth, education, age, perceptions of disparity in benefits, dependence on fishing and distance to government marine protected areas. The most frequent significant factor was the resource users’ perceived disparity between the benefits of the management to themselves and their communities, with the benefits to the government. Consequently, efforts to reduce this real or perceived disparity are likely to increase adoption and compliance rates. Most widespread positively-viewed restrictions, such as gear use and minimum size of fish, should be promoted at the national level while other restrictions may be more appropriately implemented at the community level. [ABSTRACT FROM PUBLISHER]

Abstract: Landings statistics of the Peruvian anchovy fishery show that the fishery went through a phase of explosive and uncontrolled growth from its establishment in the mid-fifties until its collapse in 1972. After the collapse, a second phase from 1973 to 1984 was characterized by unfavorable warm ocean conditions and low catches. A third phase, from 1984 to the present, with propitious ocean-environmental conditions and modern governance, can be further divided into a controlled growth period (1985–1994) and a sustainable landings'' period (1995 to present). The most recent period of the third phase has enabled the fishery to maintain its catches and be labeled as one of the most sustainable fisheries worldwide. This article highlights the evolution of the legal system that provides for the current sustainable landings and governance of this fishery. Results show that General Fisheries Acts were enacted independently of failures to sustain anchovy landings. The three Peruvian Fisheries Acts were a reflection of broader national socio-political changes and were enacted mainly to define the role of the state and private investment and to delimit foreign involvement in the fishery industry. By contrast, the enactment of secondary legislation to control quotas and fishing seasons increased as the fishery moved towards stable landings. During this phase, enacted secondary legislation showed also a clear peak during strong positive sea surface anomalies driven by the El Niño Southern Oscillation (ENSO) 1997–1998, providing evidence of rapid adaptive management. The role of Fisheries Acts in defining access rights at the national level from a multilevel governance approach is discussed and further key elements that contributed to the transition towards sustainability are suggested. [Copyright &y& Elsevier]

A discrete time bioeconomic model is developed and used to derive supply curves for the open-access and the optimally managed fisheries. Supply curves are estimated based on data for the North Sea herring fishery. Different regulatory regimes in the fishery over the past two decades, both actual and theoretical, are evaluated with respect to effects on supply, stock level, and fishing effort. The results indicate that different regulations can have a substantial impact on the supply of North Sea herring. It is argued that the annual equilibrium supply can vary from zero in case the stock is driven to extinction under open access, to a sustainable annual yield of 690-700,000 tonnes. [ABSTRACT FROM AUTHOR]

Lobster condos, artificial habitats used as aggregation devices, are the predominant collection tool for commercial fishers in The Bahamas. Despite the fact that deployed lobster condos are in excess of a million, there has not been a study focusing on how or why local fishers are using these artificial habitats, or how they should be managed. Currently, the Bahamian government is considering the creation of new laws to regulate the use of condos within national waters. The Bahamian spiny lobster fishery is not currently deemed overfished, but there is uncertainty regarding lobster populations, current fishing methods, and successful management strategies. Although Maritime Stewardship Council certification was granted in 2018, more information on condo use and overall monitoring was deemed necessary. In this paper, we investigate fisher beliefs regarding current and potential regulations, and propose management strategies for the Bahamian spiny lobster fishery. Through informal interviews and semi-structured surveys, we examined the use of lobster condos by fishers, and stakeholder beliefs on regulating lobster condos and the lobster fishery more broadly. We found general support for regulating the use of condos, but island-level trends in the type of condo restriction supported. This research can be used to inform the policy process in The Bahamas as existing regulations are revised and new laws are developed, and can influence policy creation in similar small island fisheries. • Marine Stewardship Council certification enhances fishery export competitiveness. • Effective fishery regulation requires enforceability and social sustainability. • Caribbean nations are underrepresented in sustainability certifications. • Understanding stakeholder perspectives improves management outcomes. [ABSTRACT FROM AUTHOR]

The northernmost commercial fisheries in the world take place in the northern Barents Sea up to around 80° N. This is an area where global warming is particularly intense and where large, previously ice-covered areas are now more accessible to fishing vessels. This raised questions whether existing conservation and management measures are adequate. In this paper, we discuss the process of developing new regulatory measures, including four large preliminary closed areas covering 442,022 km2 and an additional ten closed areas covering more than 3260 km2 that protects sites with biodiversity, specific to the region. The new measures, an amendment to an old regulation related to the management of impacts from bottom fisheries on ecosystems, is based on knowledge derived from more than 10 years of scientific surveys of the seabed ecology. A key finding here is that cost-efficient, large-scale mapping and monitoring of seabed ecosystems is important for the development of area-based regulations of fishing activities. In the process of developing the regulation the Directorate of Fisheries made its own analysis of the data from the scientific surveys by a novel approach using commercially available software. Such area-based measures also contribute to the achievement of Aichi target 11 and UN Sustainable Development Goal 14.5 on protecting maritime areas. [ABSTRACT FROM AUTHOR]