Management Of Commercial Fisheries Research Articles

Integrating Māori Perspectives in Environmental Management and Fisheries

Māori perspectives on environmental management advocate for a balanced and interconnected approach, prioritising long-term sustainability. This contrasts with more reductionist and economically driven approaches focussed on short-term commercial gains. This paper provides an overview New Zealand’s Quota Management System (QMS) and Māori fishing rights. The paper describes aspects of mātauranga Māori (Māori knowledge), explaining key concepts such as kaitiakitanga (guardianship) and their application in commercial fisheries management. The research highlights how Māori-owned fishing companies balance economic interests with cultural and environmental stewardship, exceeding regulatory requirements to protect marine environments. The paper discusses the challenges faced by the industry, including environmental issues and public pressure for sustainability, while also noting the growth potential, particularly in aquaculture. By analysing the successful integration of Māori worldviews within the commercial fishing sector, this paper demonstrates the potential for reconciling Indigenous knowledge systems with modern resource management practices. It concludes that the Māori approach to fisheries management offers valuable insights for balancing economic development with ecological and cultural preservation.

Optimising the review of electronic monitoring information for management of commercial fisheries

Electronic monitoring (EM) systems incorporating cameras and other devices can collect a broad range of data to support fisheries management. We reviewed the data collection capabilities of EM and considered approaches to increasing efficiency, including cost effectiveness, of EM review. EM can provide information on catch, effort, catch handling, bycatch mitigation, fishing gear and operational data, which are relevant for fisheries management including by Regional Fisheries Management Organisations (RFMOs). Methods to increase efficiency and decrease costs of EM review apply from the programme design phase, through data collection and review. At review, costs may be reduced by sampling imagery optimally to meet monitoring objectives. Considering RFMOs as users of EM-collected information, we applied EMoptim, an open-source simulation model developed in R that estimates the amount of EM review necessary to meet one or more user-specified monitoring objectives. EMoptim uses stratification to increase review efficiency and incorporates a function to explore review costs against the monitoring objectives set. We evaluated the amount of EM review needed to estimate catch with specified precision, using fishery data available from the Western and Central Pacific Fisheries Commission. Model outputs show that EM review requirements increase as catch frequency decreases, dispersion of catch events increases, and when more precise catch estimates are required. Geographical stratification reduced the amount of review required for more commonly caught species and when catch events were focused in a limited area. Optimising review rates across multiple monitoring objectives was most effective for more commonly caught species. We highlight opportunities for future use and development of this prototype modelling package.

Participation in collaborative fisheries research improves the perceptions of recreational anglers towards marine protected areas

Collaborative fisheries research programs engage stakeholders in data collection efforts, often with the benefit of increasing transparency about the status and management of natural resources. These programs are particularly important in marine systems, where management of recreational and commercial fisheries have historically been contentious. One such program is the California Collaborative Fisheries Research Program (CCFRP), which was designed in 2006 to engage recreational anglers in the scientific process and evaluate the efficacy of California’s network of marine protected areas. CCFRP began on the Central Coast of California and expanded statewide in 2017 to include six partner institutions in three regions: Northern, Central, and Southern California. To date, over 2,000 volunteer anglers have participated in the program, with many anglers volunteering for multiple years. However, the impacts of outreach, education, and collaborative research on those anglers at the statewide scale are currently unknown. Thus, the objective of the current study was to survey the statewide pool of volunteer anglers to assess the degree to which participation in CCFRP has influenced angler perceptions of MPAs, fisheries management, and conservation. We received 259 completed surveys out of a pool of 1,386 active anglers, equating to an 18.7% response rate. Participation in CCFRP resulted in a significant, positive impact on anglers’ attitudes towards MPAs in California across all regions. Anglers who participated in six or more CCFRP fishing trips had a more positive perception of MPAs than those who participated in fewer trips. Volunteer anglers across all regions perceived that they caught larger fishes, a higher abundance of fishes, and a greater diversity of species inside MPAs, consistent with the ecological findings of the program. These results highlight the benefits of involving community members in collaborative scientific research. Collaboration between researchers and the broader community increases transparency and trust between stakeholders, and results in greater understanding of natural resource dynamics, ultimately producing better management outcomes.

Southern responses to Northern-led sustainability certification: Promoting and hindering new fisheries governance in The Gambia, West Africa

Ocean governance is constituted by a range of institutions and actors across nation-states, markets, civil society and communities. As government-led management of commercial wild capture fisheries came under increased scrutiny following the rise of neo-liberalism and overfishing in the late 20th century, many non-governmental organizations and businesses turned to market and consumer-oriented approaches such as eco-labels and certification systems to define and reward sustainable fisheries and to incentivize change in others. However, our understanding of how small-scale fisheries in the Global South engage with these systems over time remains limited, particularly in the African context. This paper seeks to improve understanding by examining the interactions between diverse actors working to achieve Marine Stewardship Council certification for a small-scale fishery in The Gambia, West Africa, one of the earliest in Africa to engage the program. Situating the study within social science research on inequities and power imbalances in Southern engagements with Northern-led sustainability certifications, the case study analyzes qualitative data from documents and from 16 key-informant interviews. The data was organized using a social science approach which enables the analysis of factors promoting or hindering governance interactions and of who and what drives outcomes. Taking multiple factors into account, this paper argues that Southern interest in, and accessibility to, certification is dynamic, and influenced by the uneven distribution of regulatory resources, capacity, power and benefits. Promised but nebulous benefits clashed with arduous and recurring appraisals, exacerbating institutional factors leading the fishery to repeatedly fall short of certification. While important improvements can be gained from the pursuit of certification, Southern producers, managers and policy makers should have opportunities to be better informed about the diverse factors impacting: i) governance interactions and capacity building, ii) paths towards, and barriers to, improvements, and ii) the likelihood, or not, for achieving equitable access and social development benefits, especially for marginalized producers. The role and significance of sustainability certification in future ocean governance will be shaped fundamentally by such knowledge.

Acoustic telemetry informs conditional capture probability of an anadromous fish

Information on movement ecology and susceptibility to fishing gears is becoming increasingly employed in the management of commercial fisheries. This study combined acoustic telemetry (n = 51 and 52) and a simple passive integrated transponder (PIT) tag (n = 1499 and 1113) mark-recapture study, across two successive years on a commercial river lamprey (Lampetra fluviatilis) fishery, to inform exploitation rates and the influence of conditional capture probability on expected catch-per-unit-effort (CPUE). The movements of acoustic-tagged lamprey were used to refine estimates of the number of PIT-marked individuals vulnerable to the fishery. In 2018, this increased the recapture rate estimation by 0.99% and reduced the estimated run size by 152,101 (21.6%; 95% CL, 148,683, 155,688) individuals, with corresponding values of 0.12% and 114,639 (25.0%; 95% CL, 112,900, 116,448) in 2019. Lamprey movements were similar between years, with the number of trap line encounters by individuals between trap lifts used to inform expected CPUE for each lift. Conditional capture probability was mainly dependent on environmental conditions (e.g., river flow) with most trap lifts in the expected CPUE range, although the impacts of behaviour on vulnerability to capture were difficult to disentangle. This study highlights how the incorporation of acoustic telemetry increased the accuracy of, validated, and complemented mark-recapture data, without which management decisions (e.g., quota size) would have been based upon over 100,000 more individuals (27.5% higher than the adjusted run size in 2018 and 33.3% higher in 2019), with potentially severe consequences for the population. These findings demonstrate the importance of understanding fish movement to improve and inform fishery management. The study also presents a framework to quantify conditional capture probability and its influence on CPUE; knowledge that is widely applicable across aquatic systems for management and sustainability of fisheries.

Research Challenges, Recent Advances, and Popular Datasets in Deep Learning-Based Underwater Marine Object Detection: A Review.

Underwater marine object detection, as one of the most fundamental techniques in the community of marine science and engineering, has been shown to exhibit tremendous potential for exploring the oceans in recent years. It has been widely applied in practical applications, such as monitoring of underwater ecosystems, exploration of natural resources, management of commercial fisheries, etc. However, due to complexity of the underwater environment, characteristics of marine objects, and limitations imposed by exploration equipment, detection performance in terms of speed, accuracy, and robustness can be dramatically degraded when conventional approaches are used. Deep learning has been found to have significant impact on a variety of applications, including marine engineering. In this context, we offer a review of deep learning-based underwater marine object detection techniques. Underwater object detection can be performed by different sensors, such as acoustic sonar or optical cameras. In this paper, we focus on vision-based object detection due to several significant advantages. To facilitate a thorough understanding of this subject, we organize research challenges of vision-based underwater object detection into four categories: image quality degradation, small object detection, poor generalization, and real-time detection. We review recent advances in underwater marine object detection and highlight advantages and disadvantages of existing solutions for each challenge. In addition, we provide a detailed critical examination of the most extensively used datasets. In addition, we present comparative studies with previous reviews, notably those approaches that leverage artificial intelligence, as well as future trends related to this hot topic.

Itchthyofaunal Composition, Abundance, and Diversity Indices in Zobe Reservoir of Katsina State, Nigeria

Capture fishery is one of the dependable sources of fish protein and livelihood. This study investigated Ichthyofaunal diversity in Zobe reservoir for a period of twelve months (March 2020 to February 2021). Individual fishermen catch was used throughout the study period, where each of the five (5) Landing sites was visited twice monthly for catch assessment survey. Fish samples were randomly collected from 5 canoes/fishermen per sampling unit and catches examined. Thirteen (13) fish species (Clarias gariepinus, Oreochromis niloticus, Schilbe mystus, Synodontis membranaceous, niloticus, Bagrus docmac, Bagrus bayad, Alestes dentex, Tilapia Mozambique, Clarias anguilaris, Momyrus rume, Sarotherodon galileus, Alestes nurse and Tilapia zilli) belonging to eight genera from 7 families were observed. Oreochromis niloticus of the family Cichlidae was the most dominant species constituting 34.7%, 35.6%, 24.8%, 26.99%, and 27.3%, for Raddawa, Tabobi, Gada, Garhi, and Makera respectively, of the total catch in each fishing station of the reservoir. Diversity indices estimated from all the five stations include Shannon’s index of diversity index (H’); with a monthly range of 1.81 to 2.34, Simpson’s dominance index (C); 0.10 to 0.78, Simpson’s index (1-D); 0.10 to 0.78, Species evenness index (E); ranging from 0.596 to 1.00, species richness of Margalef’s index (d); 1.40 to 1.53, and reciprocal of Simpson’s index (D’); 1.29 to 9.96. Fish species are highly diverse with good species richness and evenness. This study validated the fisheries resources for commercial activity and fishery management of the reservoir. Therefore, stakeholders should utilize optimally and commercially the fishery resources for job creations.

Bioeconomic Modelling in Sustainable Fisheries Management of Commercial Marine Fisheries in Kelantan, Malaysia

Bioeconomic modelling is an important issue in sustainable fisheries management of commercial marine fisheries in Kelantan, Malaysia. Previous studies focus on the impact of trawling on fisheries, tourism and the socio-environment, which overfishing is a direct threat to local fishing communities. In addition, bottom trawl fishing may affect fishing, environment and socio-economic management objectives. Moreover, fishing activities lead to changes in the structure of marine habitats and affect the diversity, composition, biomass and productivity of related biota. Finally, the previous research discussed on challenges of the fisheries industry in peninsular Malaysia. Studies focused on bioeconomic modelling in sustainable management of commercial marine fisheries in terms of fishing gear, climate changes, and anthropogenic disturbances are still limited. This study aims to investigate the sustainability of marine fish production and analyse the potential effect of climate changes and anthropogenic disturbances that affect fisheries activities. The theory and practice of the bioeconomic surplus production model by Gordon - Schafer (GS) are used to calculate the total biology and economic value. The result of the study indicated that trawl nets, anchovy purse seinses, climate changes and anthropogenic disturbances affect the sustainable management of commercial marine fisheries in Kelantan, Malaysia.

This is no longer a Bristol Bay Fishery”: Fisheries dispossession and colonial violence in Bristol Bay, Alaska

Throughout Alaska, Indigenous fishing communities have been disproportionately and negatively impacted by policies that privatize access rights to the commercial fisheries. While the deleterious impacts of fisheries privatization on Alaska Native and rural Alaskans’ cultural lifeways, family systems, household economies, and community health have been extensively documented, the ways in which the dispossession of commercial fishing rights has contributed to colonial violence is less understood. Drawing on a community-based participatory study examining the colonial roots of sexual and domestic violence in Bristol Bay, Alaska, this paper explores Alaska Native survivors’ experiences with the shifts in commercial fisheries management systems, their perspectives of cultural and community changes brought on by fisheries privatization, and connection between those changes and colonial violence. The findings show that privatization processes—which have been commonly heralded as an economic and environmental solution to fisheries management—have profound socio-cultural effects that contribute to broader social ills of violence against women and substance abuse that are endemic to many of Alaska’s rural hubs and villages. These findings inform a broader social and political mandate for Indigenous Ocean justice to advance Tribal sovereignty and self-determination in fisheries management.

The perception of the issue of spawner harvesting in lakes by the owners and managers of the entities authorised to commercial and reacreational fisheries management

Abstract In recent years, the issue of spawner harvesting has been frequently addressed by different groups of stakeholders involved in the exploitation of fish resources. The increasingly numerous angling circles, which use these resources recreationally, question the current rules of fish stocking management in Poland, and its legal and economic status has become the focus of scientists’ interest. The aim of the study was to present and discuss the results of a questionnaire survey addressed to managers and owners of lake fisheries entities in order to identify the determinants of fisheries management related to spawner harvesting. Questionnaires were collected from a total of 76 entities, and concerned 1921 lakes with a total area of 174,078 ha, which accounts for more than 64% of the total area of lakes used for fishing and angling purposes in Poland. The paper presents inter alia the occupational characteristics of the respondents; their positions on the effect of spawner harvesting on lake ecosystem, environmental protection, and social factors; anglers’ assessments of spawner harvesting; the actual and potential methods for regulating this harvesting; and the negative and positive effects of the introduction of a prohibition on this harvesting. The results show that the respondents under study generally do not see the need for the introduction of additional (except those already in place) regulations concerning spawner harvesting, most of them notice the adverse effects of their introduction, but they are also aware of the possible changes and their impact on management.

Assessing the impact of management on sea anglers in the UK using choice experiments

Recreational sea angling is a popular activity generating significant socio-economic benefits but can impact on fish stocks. The motivations of recreational sea anglers go beyond catch, with a diverse range of motivations relating to physical health and well-being. Heterogenous motives and the popularity of catch and release practices mean that applying commercial fisheries management goals (maximum sustainable yield) to recreational fisheries could result in reduced participation, increased non-compliance, and a subsequent loss of both market and non-market values generated through recreational angling activities. Hence, assessment of sea angler preferences for management is important for the development of appropriate management strategies. In this study, a choice experiment was conducted to assess sea anglers' preferences for changes in UK sea angling management measures. Stated preferences for catching, keeping, and releasing fish due to bag limits and minimum-landing sizes were assessed. Willingness to pay (WTP) estimates for marginal changes of catching the first sea bass on a trip were between £11 and £31 depending on whether the fish could be kept or released and between £11 and £28 for cod, respectively. WTP was much higher for fish caught and kept than caught and released suggesting that consumption of fish was an important motivation. Minimum size was the most considered choice attribute for respondents, while cost was less commonly considered. The implications of the findings are discussed in the context of future management of recreational fisheries.

An Assessment of How Australian Fisheries Management Plans Account for Climate Change Impacts

For Australian fisheries to remain productive and sustainable (environmentally and commercially), there is a need to incorporate climate change considerations into management and planning, and to implement planned climate adaptation options. Here, we determine the extent to which Australian state fisheries management documents consider issues relating to climate change, as well as how frequently climate change is considered a research funding priority within fisheries research in Australia. We conduct a content analysis of fisheries management documents investigating categories and themes relating to Australian state fisheries, climate, and environmental change. We also reviewed recent Research Priorities from the major fisheries research funding body for reference to climate change related themes, and the number of subsequently funded projects which considered climate change or related topics. Results show that commercial state fisheries management documents consider climate only to a limited degree in comparison to other topics, with less than one-quarter of all fisheries management documents having content relating to climate. However, we find that the south-east and south-west regions of the Australian coastline have the highest incorporation of “climate” and “environmental protection considerations” in their fisheries management documents, and that fisheries are more likely to have more “climate-related mentions” within their related management documents, if they (i) primarily target species with higher economic commercial catch values, (ii) commercial catch weights, or (iii) a greater number of commercial fish stocks existing. Only a small number of recently funded fisheries research projects considered climate change, representing only a small proportion of fisheries research investment. Given the extensive climate-driven impacts recently documented among key Australian fisheries species and associated ecosystems, we conclude that there is a clear need for fisheries management in Australia to consider longer-term climate adaptation strategies for Australian commercial state fisheries to remain sustainable into the future. We suggest that without additional climate-related fisheries research and funding, many Australian agencies and fisheries may not be prepared for the impacts and subsequent adaptation efforts required for sustainable fisheries under climate change.

Reconciling seascape genetics and fisheries science in three codistributed flatfishes.

Uncertainty hampers innovative mixed‐fisheries management by the scales at which connectivity dynamics are relevant to management objectives. The spatial scale of sustainable stock management is species‐specific and depends on ecology, life history and population connectivity. One valuable approach to understand these spatial scales is to determine to what extent population genetic structure correlates with the oceanographic environment. Here, we compare the level of genetic connectivity in three codistributed and commercially exploited demersal flatfish species living in the North East Atlantic Ocean. Population genetic structure was analysed based on 14, 14 and 10 neutral DNA microsatellite markers for turbot, brill and sole, respectively. We then used redundancy analysis (RDA) to attribute the genetic variation to spatial (geographical location), temporal (sampling year) and oceanographic (water column characteristics) components. The genetic structure of turbot was composed of three clusters and correlated with variation in the depth of the pycnocline, in addition to spatial factors. The genetic structure of brill was homogenous, but correlated with average annual stratification and spatial factors. In sole, the genetic structure was composed of three clusters, but was only linked to a temporal factor. We explored whether the management of data poor commercial fisheries, such as in brill and turbot, might benefit from population‐specific information. We conclude that the management of fish stocks has to consider species‐specific genetic structures and may benefit from the documentation of the genetic seascape and life‐history traits.

Seaweed utilisation in New Zealand

Abstract The commercial landscape of seaweed use in New Zealand (NZ) has shifted and evolved since it was last reviewed in 2006. One of the largest changes saw the introduction of Macrocystis pyrifera and green-lipped mussel spat (which is landed attached to beach-cast seaweed) into the Quota Management System—the primary tool for commercial fisheries management in NZ. There have also been policy changes around commercial harvesting and farming of Undaria pinnatifida, an introduced brown alga native to Asia. Traditionally, commercial algal utilization has been limited to agar production and beach-cast collection for aquaculture feeds, though demand for seaweed products has increased with a growing Asian population in NZ. The NZ seaweed industry is at an early developmental stage, but it has the potential to offer high quality seaweed stock and value-added products to the world market. The exploration of seaweed farming, the growing demand for seaweed fertilizers and the development of high-value bioactive products such as fucoidan has attracted interest from marine farmers and entrepreneurs. The key to success for the NZ seaweed industry rests in developing high-value products for an export market, from integrated farming, harvesting and processing that can deliver the most value, consume the least energy and generate minimal waste.

A spatially explicit individual-based model to support management of commercial and recreational fisheries for European sea bass Dicentrarchus labrax

The European sea bass (Dicentrarchus labrax) is a slow growing and late maturing high value fish that is exploited by both commercial and recreational fisheries. In recent years, scientific assessments have shown a rapid decline in spawning stock biomass around the UK attributed to poor recruitment (driven by environmental factors) and high fishing mortality. This resulted in significant reductions in the harvest of sea bass following technical measures implemented by the European Commission to conserve stocks. Individual-based models (IBMs) are simulations of individual ‘agents’ of organisms that interact with each other and their environment locally and have been shown to be effective management tools in many systems. Here, an IBM that simulates the population dynamics and spatial distribution of sea bass was developed to assess how technical management measures applied to subsets of the population impact the overall stock. Conventional stock assessment techniques were used to model the processes affecting population dynamics, while the spatial distribution was simulated using a combination of temperature preferences and information from tagging studies. The IBM was parameterised using existing knowledge from the literature and can mimic key assessment outputs used to inform management and advice on fishing opportunities. Utility of the IBM is demonstrated by simulating the population consequences of several key management scenarios based on those implemented by the European Commission, including short-term bans on pelagic trawling in spawning areas, commercial and recreational catch limits and increasing the minimum conservation reference size. The IBM has potential to complement the annual stock assessment in managing European sea bass because it models individual movement, environmental drivers and emergent spatial distribution, thereby providing enhanced predictions of management strategy outcomes that could inform spatial advice on fishing opportunities and policy.

An ensemble high‐resolution projection of changes in the future habitat of American lobster and sea scallop in the Northeast US continental shelf

AbstractAimTo address the uncertainty associated with climate‐driven biogeographical changes in commercial fisheries species through an ensemble species distribution modelling (SDM) approach.LocationNortheast US Continental Shelf Large Marine Ecosystem (NEUS‐LME).MethodsWe combined an ensemble SDM platform (BIOMOD 2) and a high‐resolution global climate model (NOAA GFDL CM2.6) to quantify spatiotemporal changes in habitat of two commercially important species in the Northeast US Continental Shelf Large Marine Ecosystem (NEUS‐LME); American lobster (Homarus americanus); and sea scallop (Placopecten magellanicus). An ensemble SDM was calibrated using multi‐decadal fisheries‐independent surveys (1984–2016). Statistically weighted species‐specific ensemble SDM outputs were combined with 80 years of projected bottom temperature and salinity changes in response to a high greenhouse gas emissions scenario (an annual 1% increase in atmospheric CO2).ResultsStatistically significant changes (p < .05) in habitat suitability for both species were found over a large portion of the study area. Sea scallop undergoes a northward shift over the study period, while American lobster moves further offshore. The ensemble projections showed that several management zones were identified with increases and decreases in species‐specific habitat. Uncertainty due to variations in ensemble member models was also found in the direction of change within each management zone.Main conclusionsThis study provides ensemble estimates of climate‐driven changes and associated uncertainties in the biogeography of two economically important species in the United States. Projected climate change in the NEUS‐LME will pose management challenges, and our ensemble projections provide useful information for climate‐ready management of commercial fisheries.

A Technical Review on Estimating Biomass of Fishes and Mammals: Non-Acoustic and Acoustic Approaches

In marine ecosystem management, estimating biomass of marine species is the most significant challenge to control the ecology and biodiversity of a specified marine area and commercial fishery management. Many top-notch researches have been conducted for estimating the biomass of fishes and mammals. Most of the researches followed mainly two methods namely non-acoustics and acoustics techniques to estimate biomass. The non-acoustic technique is a very old terminology and many environmental conditions are to be considered as constant but in the acoustics method it is a much easier and error can be eliminated by different means of transforms. acoustic techniques can be classified in to two types, i.e., active acoustic techniques, and passive acoustictechniques. In this paper, we have reviewed the major acoustic and non-acoustic techniques for estimating biomass of fish and mammals. At the same time, performance analysis among these techniques has been discussed here. An introduction to the diversity in biomass estimation techniques of fishes and mammals is the aim of our investigation.

Influence of sex on growth of juvenile Greenland halibut (Reinhardtius hippoglossoides) in the Estuary and Gulf of St. Lawrence

Understanding growth in early life stages is fundamental for commercial fisheries management, but there are few studies dealing with growth trajectory divergences occurring during the juvenile stage. We monitored the growth of individually tagged two-year-old juvenile Greenland halibut captured in the wild and maintained at 4 °C for 17 months. The animals were still at the juvenile stage (no ovary or testis development through the maturation stage) at the end of the experiment. In the absence of energetic allocation to gonad development, female juveniles were larger than male juveniles, with a greater gain in mass and length. Female juveniles rapidly reached a higher Fulton’s condition index compared to male juveniles. However, no difference in glycogen, lipid, or protein liver composition or muscle energy storage was found between the sexes. Plasma cortisol was higher in male juveniles, suggesting males were more sensitive to captivity than females. Pre-maturation divergences in juvenile growth could result in or accentuate the size-related sexual dimorphism observed in nature among adults.

Studying Kenai River Fisheries’ Social-Ecological Drivers Using a Holistic Fisheries Agent-Based Model: Implications for Policy and Adaptive Capacity

Alaska’s salmon fisheries are one of the more intensely managed natural resources in the world. The state’s salmon fisheries support recreational, subsistence, and commercial harvest with multiple billions of dollars flowing into the economy, and define the cultural identity of many Alaskans. Fishery management practices rely on historic records to set policies with two goals: to meet salmon escapement quota and to maximize salmon harvest. At the same time, rapid social and ecological changes to the sub-Arctic are already impacting salmon runs and fisheries management. Combined with the inability of fishery managers to test the outcome of proposed policy changes, an understanding of the role social and ecological drivers play in harvest and effort is required. To address the two-forked problem of understanding socio-ecological dynamics and potential policy responses to ecological and social changes, we (1) conducted stakeholder workshops to solicit key system drivers, (2) built an integrated agent based model (ABM) of the system’s socio-ecological dynamics, and (3) tested the impacts of alternative future scenarios of ecological, social, and policy changes on the system’s outcomes. We previously constructed and validated a high-fidelity, data-driven, agent-based model of the Kenai River, Alaska that simulates seasonal harvest of sockeye and Chinook salmon, the fishing activities of the personal use fishery, commercial drift, and set gillnet agents. We study the role of key stakeholder and ecological drivers, using the ABM decision support tool, and their implications for fisheries management policies. Analysis of the scenario based studies found resilience in management of commercial fisheries to changing salmon migration dynamics, a lack of adaptive capacity in recreational (personal use) dipnet users to altered sockeye salmon runs, and the possible utility of introducing management measures in the dipnet fishery to manipulate sockeye escapement levels. These findings represent the usefulness of this type of ABM in assisting fishery managers everywhere in investigating possible future outcomes of different management or ecological scenarios.

Ecosystem‐based management of Amazon fisheries and wetlands

AbstractInfrastructure development and overfishing in the Amazon make it imperative to define adequate scales for the ecosystem‐based management of commercial fisheries and the wetlands on which they depend. We mapped fisheries and fish ecology data from Brazil, Peru, Bolivia and Colombia to an explicit GIS framework of river basins and mainstems. Migratory species account for more than 80% of the known maximum catches of commercial fisheries across the Amazon. Of these migratory species, we nominated six long‐distance migratory fish taxa as flagship species to define the two main commercial fishery regions. The migrations of at least one goliath catfish species define a large‐scale longitudinal link joining the Andes, Amazon Lowlands and Amazon River estuary. Migratory Characiforms demonstrate interbasin wetland connectivity between nutrient‐rich and nutrient‐poor rivers over at least 2 million km2, or about one‐third of the Amazon Basin. We show that flooded forest area is the most important wetland variable explaining regional variations in migratory characiforme biomass as indicated by maximum annual fishery catches. The sustainable management of Amazon fisheries will require transnational cooperation and a paradigm shift from local community management alone to a more integrated approach that considers both rural and urban consumers and challenges, and the realistic life histories of migratory species.