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There has been growing international attention in recent years to the Ecosystem Approach to Fisheries, Ecologically Sustainable Development, and similar initiatives that demand a comprehensive evaluation of the social, economic, and ecological performance of fisheries. However, the practical integration and application of these aspects continue to present a significant challenge for management. Progress to date has been limited by gaps in governance, objectives, disciplinary breadth, and methods. In this study, we develop an inventory of the methods that have been proposed to be able to incorporate ecological, economic, and social objectives and to provide a more comprehensive evaluation of fisheries and management. Our inventory includes both a description of the range of methods, and an evaluation against a set of criteria related to their utility in an applied, decision support context. [ABSTRACT FROM AUTHOR]

While international agreements and legislation call for incorporation of four pillars of sustainability, the social (including cultural), economic and institutional aspects (the 'human dimension') have been relatively neglected to date. Three key impediments have been identified: a relative lack of explicit social, economic and institutional objectives; a general lack of process (frameworks, governance) for routine integration of all four pillars of sustainability; and a bias towards biological considerations. Practical integration requires a 'systems' approach with explicit consideration of strategic and operational aspects of management; multidisciplinary or transdisciplinary evaluations; practical objectives for the four pillars of sustainability; appropriate participation; and a governance system that is able to integrate these diverse considerations in management. We challenge all involved in fisheries to immediately take five practical steps toward integrating ecological, economic, social and institutional aspects: (1) Adopt the perspective of the fishery as a 'system' with interacting natural, human and management elements; (2) Be aware of both strategic and operational aspects of fisheries assessment and management; (3) Articulate overarching objectives that incorporate all four pillars of sustainability; (4) Encourage appropriate (and diverse) disciplinary participation in all aspects of research, evaluation and management; and (5) Encourage development of (or emulate) participatory governance. [ABSTRACT FROM AUTHOR]

Rebuilding depleted fish populations is a priority of modern fisheries management. In the U.S., strong statutory mandates extend to both the goals and process by which stocks are to be rebuilt. However, the National Standard Guidelines that govern the implementation of the Magnuson-Stevens Fishery Conservation and Management Act may change to increase flexibility in rebuilding requirements. In this study we evaluate performance of the status quo approach to fish stock rebuilding in the United States against 3 alternatives that have been proposed to improve rebuilding outcomes. These alternatives either simplify the analytical requirements of rebuilding analyses or apply ‘best practices’ in fisheries management, thereby avoiding the need for rebuilding analyses altogether. We use a Management Strategy Evaluation framework to evaluate rebuilding options across 6 fish life history types and 5 possible real-world fishery scenarios that include options for stock assessment quality, multiple fleets, and the degree to which the stocks are overfished at the start of the analysis. We show that the status quo rebuilding plan and a harvest control rule that reduces harvest rates at low stock size generally achieve the best rebuilding outcomes across all life-history types and fishery scenarios. Both approaches constrain fishing in the short term, but achieve high catches in the medium and long term as stocks rebuild to productive levels. These results support a growing body of literature that indicates that efforts to end overfishing early pay off in the medium- to long-term with higher cumulative catches than the alternative. [ABSTRACT FROM AUTHOR]

Despite broad recognition of the potential for significant spatial complexity in morphological, behavioral, and life-history traits within many fish populations, fisheries are commonly managed across large spatial scales that aggregate interacting sub-populations into single management units. Such mis-match between the ecological and management scales may lead to a loss of spatial diversity and a restricted ability of populations to adapt and persist in the presence of changing environmental conditions. Developing harvest strategies for spatially complex fish populations therefore remains a major challenge. In this study, we evaluate whether managing spatially complex fish stocks as large-scale aggregates leads to greater conservation risks. We develop a closed-loop simulation model that represents a range of dispersal scenarios and includes imperfect management knowledge about the abundances and dynamics of interacting Pacific herring ( Clupea pallasi ) sub-populations, as well as weak management control of how exploitation is allocated among sub-populations. The latter is driven by the spatial dynamics of the fishing fleet as it seeks to optimize profitability. Simulated management outcomes did not always lead to increased risks under all scenarios of dispersal, fishery spatial dynamics, and management errors. Instead, these processes interacted to either mediate or intensify the impact of inappropriate management assumptions and stock assessment errors. Management strategies aimed directly at limiting exploitation risk consistently protected spatially complex populations in the presence of incorrect management assumptions about stock structure, high fishing power, and persistent stock assessment errors. Given the pervasiveness of these errors in fisheries, we recommend further evaluation of spatio-temporal refugia for tactical management of spatially complex fish populations. [ABSTRACT FROM AUTHOR]

The response of Pacific hake (Merluccius productus) to recent changes in ocean conditions has been dramatic, with a larger proportion of the stock moving into Canadian waters in the 1990s. Additionally, after 1994, hake spawned in Canadian waters and a portion of the stock remained year round. The change in distribution corresponded with a change in growth of juvenile hake. These changes were examined in relation to upwelling and temperature. We also examined these changes in relation to changes in the abundance of euphausiids, which are the primary food supply. We propose that the 1989 regime shift differentially affected the availability of euphausiids in the northern and southern Coastal Upwelling Domain, with feeding conditions in the north improved relative to those in the south. This promoted faster growth of juveniles in the northern regions during the 1990s. [ABSTRACT FROM AUTHOR]

Large-scale shifts occurred in climatic and oceanic conditions in 1925, 1947, 1977, 1989 and possibly 1998. These shifts affected the mix and abundance of suites of coexisting species during each period of relative environmental stability—from primary producers to apex predators. However, the 1989 regime shift was not a simple reversal of the 1977 shift. The regime shifts occurred abruptly and were neither random variations nor simple reversals to the previous conditions. Timing of these anomalous environmental events in the North Pacific Ocean appears to be linked to physical and biological responses in other oceanic regions of the world. Changes in the atmospheric pressure can alter wind patterns that affect oceanic circulation and physical properties such as salinity and depth of the thermocline. This, in turn, affects primary and secondary production. Data from the North Pacific indicate that regime shifts can have opposite effects on species living in different domains, or can affect similar species living within a single domain in opposite ways. Climatic forcing appears to indirectly affect fish and marine mammal populations through changes in the distribution and abundance of their predators and prey. Effects of regime shifts on marine ecosystems are also manifested faster at lower trophic levels. Natural variability in the productivity offish stocks in association with regime shifts indicates that new approaches to managing fisheries should incorporate climatic as well as fisheries effects. [ABSTRACT FROM AUTHOR]

This paper aims to provide advice on rebuilding Outside Yelloweye Rockfish (OYE) using a combination of stakeholder-manager-science consultations and closed-loop simulation modelling to test performance of a set of candidate management procedures (MPs) against specific quantitative objectives. The overall approach aims to expose the ecological and fishery consequences of specific analytical (e.g., data collection, assessment methods) and management choices (e.g., harvest control rules, target fishing mortality rates) for Yelloweye rebuilding. The key components of this work are: (i) development of two-stock hierarchical agestructured operating models for OYE that represent a range of hypotheses about natural mortality and exploitation history, (ii) testing MPs comprised of monitoring data, assessments, and harvest control rules (HCR) used to implement rebuilding policies, and (iii) evaluating performance measures that are used in determining the expected conservation performance of alternative MPs relative to stated rebuilding objectives. Alternative data scenarios produced a wide range of estimated stock status, as well as biological and management parameters, from which 4 representative operating models (OMs) (using a 1960 or 1918 start year and alternative catch scenarios) were selected for simulation testing MPs. The 4 OMs ranged in current biomass from approximately 2,600 to 8,200 t in the North (groundfish management areas 5BCDE) and 1,900 to 4,400 t in the South (groundfish management areas 3CD5A). This range is considerably wider than the statistical uncertainty within any particular OM. No single factor clearly explains the range of biomasses because natural mortality, absolute catch levels, and historical recruitments all affect biomass and recruitment estimates either directly or indirectly. The 1960 start year generally has the higher unfished and current biomass, while the lower bound commercial catch scenario leads to the lower unfished and current biomass. None of the 4 OMs indicate that either OYE stock area has been fished to less than 20% of the unfished level or below 40% of BMSY (Biomass at Maximum Sustainable Yield), as inferred in previous assessments. Model estimates of spawning biomass depletion relative to unfished levels range from 29-51% in the North, 21-43% in the South, and 27-48% coastwide. These correspond to 111-185% of BMSY in the North, 75-154% in the South, and 96-173% coastwide. The candidate MPs evaluated include three different assessment methods: i) a catch-at-age (CAA) assessment model, ii) a surplus production (SP) assessment model, and iii) an empirical rule (IDX) using survey index trends. The three assessment methods were used in combination with different harvest control rules or implementation error scenarios to create a set of candidate MPs that were simulation tested for each of the 4 OMs for North and South areas independently. Performance statistics were evaluated using combined outputs across OMs via a 50%-16.67%-16.67%-16.67% weighting scheme. Simulations of MP performance for setting future OYE total allowable catches (TACs) generally showed robust, or potentially robust, performance to a wide range of OM scenarios. The CAA MPs were tuned to achieve a target fishing mortality rate that would provide relatively stable OYE biomass over the projection period and biomass in both the North and South areas. Management procedures based on SP models or survey index trends (IDX) produced a range of increases or stable trends in future OYE biomass. The IDX MPs were tuned to avoid biomass declines in the first 10 years, which produced long-term increases or stable trends in biomass with high inter-annual catch variability. Although the SP models generally led to biomass increases, they did so because of under-estimation biases and often showed erratic patterns in TACs. It is likely that undesirable properties of IDX and SP MPs could be improved via further tuning. [ABSTRACT FROM AUTHOR]

Biological reference points (BRPs) in fisheries policy are typically sensitive to stock assessment model assumptions, thus increasing uncertainty in harvest decision-making and potentially blocking adoption of precautionary harvest policies. A collaborative management strategy evaluation approach and closed-loop simulation modelling was used to evaluate expected fishery economic and conservation performance of the sablefish (Anoplopoma fimbria) fishery in British Columbia (Canada), in the presence of uncertainty about BRPs. Comparison of models derived using two precautionary harvest control rules, which each complied with biological conservation objectives and short-term economic objectives given by industry, suggested that both rules were likely to avert biomass decline below limit BRPs, even when stock biomass and production were persistently overestimated by stock assessment models. The slightly less conservative, industry-preferred harvest control rule also avoided short-term economic losses of c. CAN$ 2.7–10 million annually, or 10–50% of current landed value. Distinguishing between the role of BRPs in setting fishery conservation objectives and operational control points that define harvest control rules improved the flexibility of the sablefish management system, and has led to adoption of precautionary management procedures. [ABSTRACT FROM PUBLISHER]

An interdisciplinary team of academics and representatives of fishing fleets and government collaborated to study the emerging requirements for sustainability in Canada's fisheries. Fisheries assessment and management has focused on biological productivity with insufficient consideration of social (including cultural), economic, and institutional (governance) aspects. Further, there has been little discussion or formal evaluation of the effectiveness of fisheries management. The team of over 50 people (i) identified a comprehensive set of management objectives for a sustainable fishery system based on Canadian policy statements, (ii) combined objectives into an operational framework with relevant performance indicators for use in management planning, and (iii) undertook case studies that investigated some social, economic, and governance aspects in greater detail. The resulting framework extends the suite of widely accepted ecological aspects (productivity and trophic structure, biodiversity, and habitat–ecosystem integrity) to include comparable economic (viability and prosperity, sustainable livelihoods, distribution of access and benefits, regional–community benefits), social (health and well-being, sustainable communities, ethical fisheries), and institutional (legal obligations, good governance structure, effective decision-making) aspects of sustainability. This work provides a practical framework for implementation of a comprehensive approach to sustainability in Canadian fisheries. The project also demonstrates the value of co-construction of collaborative research and co-production of knowledge that combines and builds on the strengths of academics, industry, and government. [ABSTRACT FROM AUTHOR]

Abstract: Fisheries sustainability is recognized to have four pillars: ecological, economic, social (including cultural) and institutional (or governance). Although international agreements, and legislation in many jurisdictions, call for implementation of all four pillars of sustainability, the social, economic and institutional aspects (i.e., the “human dimensions”) have not been comprehensively and collectively addressed to date. This study describes a framework for comprehensive fisheries evaluation developed by the Canadian Fisheries Research Network (CFRN) that articulates the full spectrum of ecological, economic, social and institutional objectives required under international agreements, together with candidate performance indicators for sustainable fisheries. The CFRN framework is aimed at practical fisheries evaluation and management and has a relatively balanced distribution of elements across the four pillars of sustainability relative to 10 alternative management decision support tools and indicator scorecards, which are heavily focused on ecological and economic aspects. The CFRN framework has five immediate uses: (a) It can serve as a logic frame for defining management objectives; (b) it can be used to define alternate management options to achieve given objectives; (c) it can serve as a tool for comparing management scenarios/options in decision support frameworks; (d) it can be employed to create a report card for comprehensive fisheries management evaluation; and (e) it is a tool for practical implementation of an integrated social–ecological system approach. [ABSTRACT FROM AUTHOR]

Fishers' knowledge research (FKR) aims to enhance the use of experiential knowledge of fish harvesters in fisheries research, assessment, and management. Fishery participants are able to provide unique knowledge, and that knowledge forms an important part of "best available information" for fisheries science and management. Fishers' knowledge includes, but is much greater than, basic biological fishery information. It includes ecological, economic, social, and institutional knowledge, as well as experience and critical analysis of experiential knowledge. We suggest that FKR, which may in the past have been defined quite narrowly, be defined more broadly to include both fishery observations and fishers "experiential knowledge" provided across a spectrum of arrangements of fisher participation. FKR is part of the new and different information required in evolving "ecosystem-based" and "integrated" management approaches. FKR is a necessary element in the integration of ecological, economic, social, and institutional considerations of future management. Fishers' knowledge may be added to traditional assessment with appropriate analysis and explicit recognition of the intended use of the information, but fishers' knowledge is best implemented in a participatory process designed to receive and use it. Co-generation of knowledge in appropriately designed processes facilitates development and use of fishers' knowledge and facilitates the participation of fishers in assessment and management, and is suggested as best practice in improved fisheries governance. [ABSTRACT FROM AUTHOR]