Renewed interest in the estimation of spatial and temporal variation in fish traits, such as body size, is a result of computing advances and the development of spatially-explicit management frameworks. However, many attempts to quantify spatial structure or the distribution of traits utilize a priori approaches, which involve pre-designated geographic regions and thus cannot detect unanticipated spatial patterns. We developed a new, model-based method that uses the first derivative of the spatial smoothing term of a generalized additive model to identify spatial zones of variation in fish length-at-age. We use simulation testing to evaluate the method across a variety of synthetic, stratified age and length datasets, and then apply it to survey data for Northeast Pacific sablefish (Anoplopoma fimbria). Simulation testing illustrates the robustness of the method across a variety of scenarios related to spatially or temporally stratified length-at-age data, including strict boundaries, overlapping zones and changes at the extreme of the range. Results indicate that length-at-age for Northeast Pacific sablefish increases with latitude, which is consistent with previous work from the western United States. Model-detected spatial breakpoints corresponded to major oceanographic features, including the northern end of the Southern California Bight and the bifurcation of the North Pacific Current. This method has the potential to improve detection of large-scale patterns in fish growth, and aid in the development of spatiotemporally structured population dynamics models to inform ecosystem-based fisheries management.
Ecosystem-based Management (EBM)
Globally, conflicts between marine nature conservation and fishery interests are common and increasing, and there is often a glaring lack of dialogue between stakeholders representing these two interests. There is a need for a stronger and enforced coordination between fishing and conservation authorities when establishing marine protected areas for conservation purposes. We propose that an appropriate instrument for such coordination is a broad ecosystem-based marine spatial planning procedure, representing neither nature conservation nor fishery. Strategic environmental assessment for plans and programmes and environmental impact assessment for projects are commonly used tools for assessing the environmental impacts of different human activities, but are seldom used for evaluating the environmental effects of capture fisheries. The diversity of fisheries and the drastic effects of some fisheries on the environment are strong arguments for introducing these procedures as valuable supplements to existing fisheries assessment and management tools and able to provide relevant environmental information for an overall marine spatial planning process. Marine protected areas for nature conservation and for protection of fisheries have different objectives. Therefore, the legal procedure when establishing marine protected areas should depend on whether they are established for nature conservation purposes or as a fisheries resource management tool. Fishing in a marine protected area for conservation purpose should be regulated according to conservation law. Also, we argue that marine protected areas for conservation purposes, in the highest protection category, should primarily be established as fully protected marine national parks and marine reserves.
We highlight the potential benefits of adopting Ecosystem-based Fishery Management (EBFM). We compare the EBFM implementation with the more traditional single-stock approach. We show the contribution of the portfolio theory to the EBFM, which can be achieved by selecting an optimal portfolio to maximise the average revenues and minimise the variance. We use this approach to construct two frontiers: the ecosystem efficient frontier, which considers stock interactions (the variance-covariance matrix), and the stock efficient frontier, only considering individual stock variances.
We also define two risk gaps. The first gap shows the reduction in the standard deviation per unit of revenue that the fleet could have achieved if they had decided to use the optimal portfolio of the stock frontier instead of the historical portfolio. The second gap reflects the reduction in the standard deviation per unit of revenue when the management moves from the stock frontier to the ecosystem frontier portfolio.
This approach is adapted to the Basque inshore fleet. According to our results, taking the single-stock approach as the benchmark, the EBFM would obtain the same historical revenue while reducing the risk by 23%. Alternatively, allowing the same level of risk, it could achieve a 21% increase in revenues.
Marine biodiversity is under extreme pressure from anthropogenic activity globally, leading to calls to protect at least 10% of the world’s oceans within marine protected areas (MPAs) and other effective area-based conservation measures. Fulfilling such commitments, however, requires a detailed understanding of the distribution of potentially detrimental human activities, and their predicted impacts. One such approach that is being increasingly used to strengthen our understanding of human impacts is cumulative impact mapping; as it can help identify economic sectors with the greatest potential impact on species and ecosystems in order to prioritize conservation management strategies, providing clear direction for intervention. In this paper, we present the first local cumulative utilization impact mapping exercise for the Bioko-Corisco-Continental area of Equatorial Guinea’s Exclusive Economic Zone – situated in the Gulf of Guinea, one of the most important and least studied marine regions in the Eastern Central Atlantic. This study examines the potential impact of ten direct anthropogenic activities on a suite of key marine megafauna species and reveals that the most suitable habitats for these species, located on the continental shelf, are subject to the highest threat scores. However, in some coastal areas, the persistence of highly suitable habitat subject to lower threat scores suggests that there are still several strategic areas that are less impacted by human activity that may be suitable sites for protected area expansion. Highlighting both the areas with potentially the highest impact, and those with lower impact levels, as well as particularly damaging activities can inform the direction of future conservation initiatives in the region.
Worldwide fisheries management has been undergoing a paradigm shift from a single-species approach to ecosystem approaches. In the United States, NOAA has adopted a policy statement and Road Map to guide the development and implementation of ecosystem-based fisheries management (EBFM). NOAA’s EBFM policy supports addressing the ecosystem interconnections to help maintain resilient and productive ecosystems, even as they respond to climate, habitat, ecological, and social and economic changes. Managing natural marine resources while taking into account their interactions with their environment and our human interactions with our resources and environment requires the support of ecosystem science, modeling, and analysis. Implementing EBFM will require using existing mandates and approaches that fit regional management structures and cultures. The primary mandate for managing marine fisheries in the United States is the Magnuson-Stevens Fishery Conservation and Management Act. Many tenets of the Act align well with the EBFM policy, however, incorporating ecosystem analysis and models into fisheries management processes has faced procedural challenges in many jurisdictions. In this paper, we review example cases where scientists have had success in using ecosystem analysis and modeling to inform management priorities, and identify practices that help bring new ecosystem science information into existing policy processes. A key to these successes is regular communication and collaborative discourse among modelers, stakeholders, and resource managers to tailor models and ensure they addressed the management needs as directly as possible.
The exploration of gradients of development stages of coral reef ecosystems is a subject poorly studied, especially when they exhibit multiple degrees of geomorphological or structural development or both. The objective of the present work was to study the gradient of functional and structural maturity of the Mexican Caribbean coral reefs (CM). Here we analyzed three geomorphological zones that cover a gradient of 400 km in length in order to obtain coral reefs with different geomorphologies. Thirteen reefs were selected, for which 12 ecosystem development attributes and five topological indices were analyzed. The development attributes of coral reefs were estimated from trophic models constructed using Ecopath with Ecosim (EwE), while the topological indices were calculated from the predator-prey matrix obtained from each EwE model. Through a partial redundancy analysis (RDA) seven of the 12 development attributes (ascendency, overhead, development capacity, net primary production, ascendency/development capacity, overhead/development capacity and richness of functional group) were selected due their low or null collinearity. Using the developmental attributes selected in a non-metric multidimensional scaling (stress: 0.1) and analysis of similarities (r global: 0.828 and p: 0.001), we found a gradient of maturity that increases from north to south, i.e., northern coral reefs (e.g. Puerto Morelos) are less mature than southern coral reefs (e.g. Mahahual). On other hand, through a non-parametric ANOVA and a partial redundancy analysis (first axis: F-ratio = 62.054, p = 0.012; second axis: F-ratio = 1.591, p = 0.014; 100% of the total variance explained by the first two canonical axes) we detected that topological indices respond to development stages, in this way the control flow increases with the maturity while the intermediation, number of connections and number of interactions depredator-prey are inverse to maturity; therefore, topological indices can be used to describe development stages. The determination of a gradient of maturity in MC coral reefs should be considered in management and conservation policies, therefore different strategies must be implemented in ecosystems, because resilience and ecosystem response depend on them.
The concept of ecosystem‐based fisheries management (EBFM) has been subjected to debate since it was introduced in the late 1990s. The development of the concept seems to follow two separate but simultaneous trajectories of increased popularity but also sustained critique. This paper offers an analysis of potential mechanisms behind these disparate trajectories by drawing on a theoretical framework from science and technology studies (STS) centred around "black box" and actor‐network theory. To support our analysis, we perform an exploratory literature review of how the EBFM concept has been used in a selection of high impact fisheries research papers. We find that the popularity of EBFM does not guarantee its integrity, usefulness or analytical insight, but also that persistent critique of how the concept is used seems to be driving some change. We think that a continued trajectory of increased understanding, contextualization and discernibility of EBFM can help overcome the considerable ambiguity associated with the concept and make it increasingly useful to fisheries management. This means moving away from routine use of the term towards a practicable and tangible approach to improve fisheries sustainability.
Fusilier (Pisces: Caesionidae) gillnet, called jaring lalosi, have been used since decades by fishers from Assilulu village, meanwhile its scientific information is limited. The aim of this study is to learn the reef fish species selectivity of jaring lalosi and to assess its bycatch using productivity and susceptibility assessment (PSA). This study was conducted at Pulau Tiga waters, Central Maluku Regency, for 3 months observation: October 2017, February and April 2018. Jaring lalosi which means fusilier gillnet, caught dark-banded fusilier, Pterocaesio tile, 94.4% of the total catch. The rest of the catch we represented as by-catch of jaring lalosi. As a high resilience and low vulnerability species, the sustainability of dark-banded fusilier fisheries is unlikely to be fully concerned. As high mobility schooling species, dark-banded fusilier was caught at different communities of reef fishes. MDS analysis showed discrepancy of species selectivity of fusilier gillnet by monthly catch rate. The PSA for bycatch resulted 2 reef species are least likely to be sustainable, 12 reef species are most likely to be sustainable on the criteria of recovery axis and 3 pelagic species are the most sustainable species. We concluded that the practiced of jaring lalosi has low impacts on reef fish community and tendency to overfishing is almost none as long as there is no increasing on fishing pressure. For the implementation of fisheries management based on ecosystem approach (EAFM), bycatch assessment should be applied to other fishing gears.
- For more than 40 years, marine zoning has played a key role while evolving as part of the adaptive management of the Great Barrier Reef (GBR) Marine Park. The statutory zoning plan provides the primary integrating component that prohibits many threatening activities and manages the impacts of allowed human activities and competing uses by means of various zones, special management areas and other spatial management tools.
- How zoning is applied, however, has changed considerably since the first zoning plan was finalized in 1981. Today, zoning is applied in combination with other layers of marine spatial planning; the effective combination of these management tools provides the integrated approach, considered one of the best for managing a large marine protected area.
- The zoning plan provides the foundation for management of the GBR and is the fundamental component of the integrated marine spatial planning approach ensuring high levels of protection for significant areas of the GBR, while also allowing ecologically sustainable use.
- The paper outlines the legal and managerial contexts of zoning, providing 38 lessons that may be useful for marine zoning and ecosystem‐based management elsewhere. It outlines aspects of zoning that have worked well in the GBR Marine Park and what has changed in the light of experience and changing contexts, and seeks to clarify various misconceptions about zoning and marine spatial planning.
- The integrated management approach in the GBR utilizes a variety of spatial planning tools, which complement the underlying zoning; some of these comprise statutory management layers (e.g. designated shipping areas, special management areas, plans of management, fishery management arrangements, Traditional Owner agreements, defence training areas); other layers are non‐statutory (e.g. site plans).
- This paper is written for planners, managers and decision‐makers considering the use of zoning to achieve effective marine conservation, protection and ecologically sustainable use.
Tuna Regional Fisheries Management Organizations have committed to adopting an ecosystem approach to fisheries management (EAFM). Yet their progress has been relatively slow and patchy, lacking a long-term vision and a formalized plan to prescribe how fisheries will be managed from an ecosystem perspective. We argue that one of the impediments in this process has been the lack of well-defined spatial management units that are ecologically meaningful, as well as practical for fisheries management, to guide ecosystem-based planning, research and indicator assessments, to ultimately produce better integrated management advice. In this study, we propose seven potential ecoregions within the convention area of the International Commission for the Conservation of Atlantic Tunas (ICCAT). The boundaries of the ecoregions rest on three pillars of information: the existing knowledge of biogeographic classifications of the pelagic environment, the spatial distribution of tuna and billfish species, and the spatial dynamics of the main fishing fleets targeting them. Each ecoregion is characterized by a set of ecologically meaningful biogeographic and oceanographic characteristics, tuna and billfish communities and fishing fleet patterns. The pelagic ecoregions proposed here aim to focus species- and fisheries-specific management of the tuna and billfish fisheries on specified regions. The proposed ecoregions represent an optimal, ecologically sound starting point, based on the best science available, to foster debate and consultative process in ICCAT for moving forward the implementation of the EAFM.