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Recruitment is a critical process in the dynamics of fish populations since it represents the abundance of new fish that enter a population each year. In Ekman‐type upwelling ecosystems, wind is a critical factor for small pelagic fish recruitment, as it controls food availability and physical constraints such as turbulence and offshore advection. In this study, we evaluate the effect of wind, chlorophyll‐a, and spawning biomass as independent variables on anchovy recruitment. Using generalized additive models (GAMs), we tested (i) the significance of each factor, (ii) the shape of the relationship between recruitment and predictors variables, (iii) recruitment regimes in the series, and (iv) whether extended windy events are associated with low recruitment levels potentially related to offshore transport of early life stages. The study period spanned from 1990 to 2021, focusing on the austral spring in south‐central Chile (35–40°S) when both upwelling and anchovy spawning are maximized. GAMs revealed a parabolic relationship between the velocity of upwelling‐favorable winds and anchovy recruitment. Maximized recruitment occurred at wind speeds around 6 m s−1 but decreased with winds above 7 m s−1 and below 5 m s−1, and during periods of extended windy events (i.e., those lasting more than 15 days). Chlorophyll‐a showed no significance on anchovy recruitment, suggesting that phytoplankton were not a limiting factor for anchovy early survival. We also found that anchovy recruitment regimes were associated with specific wind intensities. We discussed the pertinence of incorporating a recruitment index based on wind in the fishery management of the anchovy in south‐central Chile. [ABSTRACT FROM AUTHOR]

he continuous and intensive anchovy fishing conducted by lift net fishermen in Sibolga and Tapanuli Tengah without proper management and regulation may lead to unfavorable consequences, particularly for the sustainability of the anchovy fishery resources. One solution to address the issues mentioned above is to implement management practices for anchovy resources, ensuring their sustainability in the future. One widely used method for this purpose is the Ecosystem Approach to Fisheries Management (EAFM). This study aims to evaluate the management status and formulate management action plans for anchovy resources in Sibolga and Tapanuli Tengah. The research was conducted in the Tapanuli Tengah region, focusing on specific locations: Hajoran Village, Muara Nibong Village, Lubuk Tukko Village, and Mela I Village. Data collection was carried out through survey techniques directly in the field, employing accidental sampling and purposive sampling for sample collection. The analysis was performed using the EAFM approach. The management status of anchovy resources based on lift net fishing gear in Sibolga and Tapanuli Tengah falls into the 'good' category, indicating the need for cautious actions in its utilization. Several management actions need improvement based on indicator values, such as the declining trend in Catch Per Unit Effort (CPUE). Therefore, it is recommended to control lift net fishing efforts by regulating the number of fishing gears and imposing catch quotas. Considering the proportion of juvenile catches and the occurrence of range collapse, implementing a seasonal open-close system and regulating the placement distance of purse seine gear is necessary. [ABSTRACT FROM AUTHOR]

Natural resource management is evolving toward holistic, ecosystem‐based approaches to decision making. The ecosystem science underpinning these approaches needs to account for the complexity of multiple interacting components within and across coupled natural–human systems. In this research, we investigate the potential economic and ecological gains from adopting ecosystem‐based approaches for the sardine and anchovy fisheries off of the coast of California, USA. Research has shown that while predators in this system are likely substituting one forage species for another, the assemblage of sardine and anchovy can be a significant driver of predator populations. Currently, the harvest control rules for sardine and anchovy fisheries align more with traditional single species framework. We ask what are the economic and ecological gains when jointly determining the harvest control rules for both forage fish stocks and their predators relative to the status quo? What are the implications of synchronous and anti‐synchronous environmental recruitment variation between the anchovy and sardine stocks on optimal food‐web management? To investigate these questions, we develop an economic‐ecological model for sardine, anchovy, a harvested predator (halibut), and an endangered predator (Brown Pelican) that includes recruitment variability over time driven by changing environmental conditions. Utilizing large‐scale numerical optimal control methods, we investigate how the multiple variants of integrated management of sardine, anchovy, and halibut impact the overall economic condition of the fisheries and Brown Pelican populations over time. We find significant gains in moving to integrated catch control rules both in terms of the economic gains of the fished stocks, and in terms of the impacts on the Brown Pelican populations. We also compare the relative performance of current stylized catch control rules to optimal single species and optimal ecosystem‐based fisheries management (EBFM) across ecological and economic dimensions, where the former trade‐off considerable economic value for ecological goals. More generally, we demonstrate how EBFM approaches introduce and integrate additional management levers for policymakers to achieve non‐fishery objectives at lowest costs to the fishing sectors. [ABSTRACT FROM AUTHOR]

The anchovy (Engraulis ringens) fishery in central-southern Chile, like many fisheries worldwide, is overexploitation mainly due to poor and short-term management by fishing authorities and communities. This study proposes and evaluates marine reserves as a possible tool to apply since there is a current marine reserve law in Chile. The study's methodology is the simulation of a bioeconomic model that includes two areas: one is the protected, and the other is the artisanal fishing, in which the protected area transfers biomass to the artisanal fishing area. The reserve is incorporated as a decision variable in the management of this resource. It is determined as a percentage of protection of the total fish population related to fishing effort, which quantifies and evaluates the impact of protecting a stock of parental fish on the fishery's sustainability. Biomass data used is from 2000-2006, during which the anchovy fishery was fully exploited. The carrying capacity and intrinsic growth rate are estimated, and biomass is projected at different protection and effort levels. Results show that if a marine reserve with a protection level of 30% had been applied as a management policy in the anchovy fishery of central-southern Chile in the early 2000s, the fishing activity would be in a state of full exploitation rather than overexploitation as it is today. This model's fundamental contribution is that it makes possible fishery evaluation with real data from the same fishing activity. [ABSTRACT FROM AUTHOR]

Small pelagic fisheries management is difficult because they exhibit large natural abundance fluctuations and are considered forage fish. We discuss the challenges faced by these fisheries within the Marine Stewardship Council (MSC) sustainability certification framework, which evaluates the sustainability of fish stocks, the environmental impact, and effective fisheries management. Certification suspension is frequently linked to the sustainability of stocks. For MSC certification, scientific research will need to play a major role in filling key knowledge gaps, particularly on the nature and causes of ecosystem productivity changes (including climate change), and the role of small pelagics in the ecosystem. Different from other cases where MSC certification creates a direct market incentive through price premiums, in these fisheries, the incentive is related to fisher's public image and improves the bases for negotiation with authorities and the conservation sector. In this context, strategic cooperation between fisheries under the certification process may provide them more benefits than competition. [ABSTRACT FROM AUTHOR]

Food chain models with interactions between key species are useful tools for ecological conservation and economic sustainability in commercial fisheries. In this study, we build a food chain model coupled with optimal control theory and focus on the Black Sea anchovy population in the southern part of the Black Sea. Our objective is to find the optimal harvesting strategy that maximizes the discounted net profit value of the anchovy fishery with seasonal harvesting, and that offers sustainable anchovy fishery. As a result, we obtain profitable and sustainable harvesting strategies. We also discuss the benefits of using food chain models in fishery management rather than using single‐species models. Finally, we derive a schedule for the number of fishing vessels that are needed in the implementation of the optimal harvesting strategy. Recommendations for Resource ManagersFood chain modeling framework offers more reliable harvesting strategies than single‐species modeling framework.Managing the harvest effort using optimal control theory results in a more profitable anchovy fishery on the southern part of the Black Sea.By quantifying the relationship between the annual landing and the number of fishing vessels, we can approximate the needed number of fishing vessels to achieve an optimal landing.Applying an optimal control strategy yields more anchovy landing and profit in the long term, when we compare with the current harvesting strategy used in the anchovy fishery. These strategies also offer a sustainable anchovy fishery, which is crucial for the fate of this fishery. [ABSTRACT FROM AUTHOR]

Vessel monitoring systems (VMS) represent a tool that can provide information on the spatial and temporal distribution of fishing activity and a quantitative evaluation of the fishing effort at both spatial and temporal scales. The aim of this study was to characterise the spatio‐temporal structure of the Catalan purse seiner fishing effort directed towards anchovy or sardine, which was estimated by filtering VMS data (from 2012 to 2014) by species and seasons. The results showed that the mean location of the fishing effort directed towards anchovy did not vary among the summer seasons, in contrast to the efforts in spring and autumn, whereas the mean location of the effort directed towards sardine was constant over the seasons. The concentration curves indicated that similar fishing effort patterns occurred during all seasons when directed towards sardine, whereas the effort directed towards anchovy was more concentrated in summer. The ranges of the variograms indicated that the fishing effort directed towards both species formed patches. The dimensions of these patches changed from season to season, with the smallest magnitudes during the summer seasons. In this study, a seasonal distribution pattern of the fishing efforts was recognised that adequately captured the features of the distributions of small pelagic populations. [ABSTRACT FROM AUTHOR]

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Members of the Engraulidae (anchovies) fuel large fisheries around the globe, helping to fulfil demands for food. On the other hand, unpredictable catches that are a very common occurrence with respect to this family can have drastic consequences on economies of different countries. Like many other fisheries, the Black Sea anchovy fishery is a very good example of a fishery greatly affected by abrupt peaks and troughs in landings. In this work, the existing knowledge on the species' overwintering behavior and exploitation patterns along the south coast of the Black Sea is re-evaluated with respect to recent observations. The strong seasonality and very short fishing season are noted as the main characteristics regulating development of the fishery over time. Climatic variability may sometimes generate favorable overwintering conditions outside areas where anchovy aggregations are usually expected, resulting in a temporal shift in overwintering grounds. As most fishing activity takes place on these grounds, low catches in some years are more likely to have been due to fishing the wrong areas, rather than stock decline. This is particularly the case when geopolitical developments have reshaped the fishery, such as the collapse of the Soviet Union, whose fishing fleet once dominated the anchovy fishery. Such irregularities pose considerable management challenges, in particular stock management. Some significant harvest control strategies applied to various anchovy stocks are reviewed and discussed with respect to peculiarities of the Black Sea anchovy. [ABSTRACT FROM AUTHOR]

Information gathering can reduce critical uncertainties and, consequently, lead to better decisions on conservation and exploitation of fisheries. Such decisions might improve the fishing opportunities or lower their variability. However, information gathering comes at a cost. The concept of the expected value of information is based on the idea that decisions will be more accurate if the decision maker has more information. The objective of this work is to use this concept to measure and understand the economic value of fishery research surveys using the mathematical theory of the expected value of information. The Bay of Biscay anchovy fishery is used as an example, given the importance of the surveys in the assessment and management in this fishery. The paper provides a measure of the value of information obtained by research surveys. It also analyses the properties of these values, considering the methodology used, and examines the circumstances under which such calculations are adequate. The sources of subjectivity inherent to this methodology and to the general concept of information signals in the fishery assessment and management are explored. [ABSTRACT FROM AUTHOR]

Anchovy, Engraulis encrasicolus, forms the basis of Italian small pelagic fisheries in the Adriatic Sea. The strong dependence of this stock on environmental factors and the consequent high variability makes the dynamics of this species particularly complicated to model. Weekly geo-referenced catch data of anchovy obtained by means of a Fishery Observing System ( FOS) from 2005 to 2011 were referred to a 0.2 × 0.2 degree grid (about 20 km2) and associated with the environmental parameters calculated by a Regional Ocean Modelling System, Adria ROMS. Generalized Additive Mixed Models ( GAMM) with and without random effects were used to identify a relationship between abundance in the catch and oceanographic conditions. The outcomes of models with no random effects, with random vessel effects and with the random vessel and random week-of-the-year effects were examined. The GAMM incorporating a random vessel and week-of-the-year effect were selected as the best model on the basis of the Akaike information criteria ( AIC). This model indicated that catches (abundance) of anchovy in the Adriatic Sea correlate well with low temperatures, salinity fronts and sea surface height, and allowed the identification of areas where high concentrations of this species are most likely to occur. The results of this study demonstrate that GAMM are a useful tool to combine geo-referenced catch data with oceanographic variables and that the use of a mixed-model approach with spatial and temporal random effects is an effective way to depict the dynamics of marine species. [ABSTRACT FROM AUTHOR]

Understanding the spatiotemporal behavior of fishermen at the fleet scale is key for defining effective strategies for fisheries management. Here we classify the spatial patterns exhibited by fishing trip trajectories in the world's largest monospecific fishery, the Peruvian anchovy fishery. Our goal is to identify spatial strategies and their possible changes over 2000–2009. The data comprise more than 350,000 fishing trips, recorded using a vessel monitoring system. On-board observers monitored a small fraction of those trips (>2000), providing data for inferring the type of activity (fishing, searching, and cruising) from the position records, for use in a state-space model. Each fishing trip was characterized by its duration, maximum distance to the coast, geographical extension, and time spent fishing, searching and cruising. Using clustering techniques, we identified four types of fishing trips, associated with differences in management among regions, fleet segments, and skippers’ behavior. The methodology could be used to investigate fishing spatial strategies using VMS trajectories in other fisheries. [ABSTRACT FROM AUTHOR]

The Ecosystem Approach to Fisheries Management (EAFM) strives to balance multiple objectives of ecological wellbeing, social and economic wellbeing, and good governance. The Provincial Government of West Papua with technical support from the USAID Sustainable Ecosystems Advanced Project (SEA) has developed a fisheries management plan (FMP) for the anchovy fishery in Raja Ampat, West Papua Province of Indonesia. EAFM is the appropriate approach to manage the fishery because EAFM multiple objectives reflect the challenges and needs to ensure the sustainability of the fishery resources and to contribute to local communities. The FMP includes management issues, operational objectives, appropriate management measures, and action plans defined through a participatory process. The issues include overfishing as shown by declining anchovy catches, resource competition between local small-scale fishers and industrial fishers, limited livelihood opportunities, and an absence of a functional fishery governance institution. To address these challenges, the FMP has multiple operational objectives: to empower local livelihoods, strengthen institutional management mechanisms, and ensure anchovy resources sustainability. The integration of the socioeconomic aspect means there must be management decision trade-offs that weigh trade-offs of stock sustainability, local poverty, interests of the private sector, and addressing the horizontal conflict between locals and industrial fishers. Strengthening fisheries institutions is critical to ensure integration in resource investments and in detailing activities to implement the FMP because of the complementary roles, and lack of synergy of the multiple agencies. This holistic approach is expected to support the long-term use of the anchovy resources while partially alleviating local poverty. • Adopting the Ecosystem Approach to Fisheries Management (EAFM) into practice. • Multiple objectives of a fisheries management plan. • Ensuring locals' livelihood and fairer benefits in fishery management. • Integrating social and institutional aspects with a multidisciplinary approach in fisheries. • Adaptive management system for small-scale fisheries within customary tenure regime. [ABSTRACT FROM AUTHOR]

Many fisheries management decisions require predictions of spatial dynamics, and simulation of realistic movement is critically important for accurately representing population-level dynamics with spatially explicit individual-based models (IBMs). Movement approaches developed to date have been applied across a wide range of spatiotemporal resolutions. We compared four movement approaches or submodels (restricted-area search, kinesis, event based, and run and tumble) using an IBM (roughly based on Bay AnchovyAnchoa mitchilliand Northern AnchovyEngraulis mordax) that simulated growth, mortality, and movement of a cohort on a two-dimensional grid. We evaluated the submodels in 2.7- × 2.7-km environments at five resolutions defined by various cell sizes and time steps. We used a genetic algorithm to calibrate each movement submodel over a 300-generation training phase and then tested the mean movement parameters for a single generation in the training environment and a novel environment. Restricted-area search, kinesis, and event-based submodels had higher egg production than a random walk model (baseline, assuming no behavioral movement) across spatiotemporal resolutions in training and novel environments. The run-and-tumble submodel also had higher egg production than the random walk model but only under certain conditions. Although restricted-area, kinesis, and event-based submodels outperformed random walk at all resolutions, the submodels did not perform equally well across resolutions in terms of egg production and aggregation of model individuals in high-quality cells (i.e., those with high growth and low mortality). The variability in performance was due to the change in habitat quality experienced by model individuals from one time step to the next. Restricted-area and event-based submodels had higher egg production when model individuals experienced small changes in habitat quality, whereas the kinesis and run-and-tumble submodels performed better when model individuals experienced larger changes in habitat quality. Received October 16, 2013; accepted March 11, 2004 [ABSTRACT FROM AUTHOR]

Viñas, J., Sanz, N., Peñarrubia, L., Araguas, R-M., García-Marín, J-L., Roldán, M-I., and Pla, C. 2014. Genetic population structure of European anchovy in the Mediterranean Sea and the Northeast Atlantic Ocean using sequence analysis of the mitochondrial DNA control region. – ICES Journal of Marine Science, 71: 391–397.The European anchovy (Engraulis encrasicolus) exhibits a complex population structure in the Mediterranean Sea and Northeast Atlantic Ocean. To resolve the population genetic structure of this species, we surveyed sequence variability in the mitochondrial (mtDNA) control region in samples (n = 563) from 13 locations in the Northeast Atlantic, the Bay of Biscay, and the Mediterranean Sea. Based on pairwise ΦSTs, SAMOVA, and multidimensional scaling, a complicated population structure composed of multiple populations emerged. Combining these results with those from previous population studies based on mitochondrial and nuclear markers, we identified nine genetically differentiated European anchovy populations: (i) Canary Islands; (ii) Cádiz; (iii) Alborán Sea; (iv) Garona; (v) Arcachon and Donostia; (vi) a large population in the northwestern Mediterranean, including Cadaqués, Gulf of Lyon, Elba, and Sicily; (vii) southern Adriatic; (viii) northern Adriatic; and (ix) Aegean Sea. We suggest that independent management strategies should be implemented for each genetically differentiated population, and, in cases where several fisheries stocks are recognized within an area of genetic homogeneity, each stock should be managed separately. [ABSTRACT FROM PUBLISHER]

This paper examines the viability of the management of a transboundary fishery. In a deterministic dynamic framework, we consider a fish stock with two age groups, juveniles and adults, exploited by two countries having a different impact on the age groups. A regulatory agency defines an annual total allowable catch and its allocation between the two countries. We consider allocations satisfying a set of constraints representing viability conditions. The constraints include a minimal quota and minimal profit for each country. We compare intertemporal viable trajectories with the trajectory resulting from a cooperative game in which the two countries agree on the maximization of the fishery's total profit. While the cooperative solution consists in allocating the whole fishing effort to the most efficient country, the viable solution ensures a limitation of inequalities but reduces the overall economic outcome. The results are illustrated for the Bay of Biscay anchovy (Engraulis encrasicolus L.), exploited by Spain and France, with two different types of gear, the purse seine for Spain and the pelagic trawl for France. [ABSTRACT FROM AUTHOR]

Abstract: A multi-species approach to fisheries management requires taking into account the interactions between species in order to improve recruitment forecasting of the fish species. Recent advances in Bayesian networks direct the learning of models with several interrelated variables to be forecasted simultaneously. These models are known as multi-dimensional Bayesian network classifiers (MDBNs). Pre-processing steps are critical for the posterior learning of the model in these kinds of domains. Therefore, in the present study, a set of ‘state-of-the-art’ uni-dimensional pre-processing methods, within the categories of missing data imputation, feature discretization and feature subset selection, are adapted to be used with MDBNs. A framework that includes the proposed multi-dimensional supervised pre-processing methods, coupled with a MDBN classifier, is tested with synthetic datasets and the real domain of fish recruitment forecasting. The correctly forecasting of three fish species (anchovy, sardine and hake) simultaneously is doubled (from 17.3% to 29.5%) using the multi-dimensional approach in comparison to mono-species models. The probability assessments also show high improvement reducing the average error (estimated by means of Brier score) from 0.35 to 0.27. Finally, these differences are superior to the forecasting of species by pairs. [Copyright &y& Elsevier]

In January 2009 a new management regime of individual vessel quotas (IVQs) was put in force in the world's largest fishery, the Peruvian anchovy fishery. Until 2009, the fishery was managed by a regulated open-access system with clear symptoms of the race for fish. We argue that the new regime has stopped the race for fish, reduced the number of vessels participating in the fishery, and prolonged the fishing season. Furthermore, the IVQs appear to have improved profitability in the fishery and increased value-added production in the Peruvian anchovy value chains. This provides support that developing countries with presumed weaker institutions can reap benefits of such management systems. However , there appears to have been setbacks in 2010, as the number of participating vessels has once again increased. This indicates that the institutions that regulate and monitor the fishery must be further strengthened. [ABSTRACT FROM AUTHOR]

Given the low biomass level of the anchovy, the European Commission agreed to establish a moratorium on this species in the Bay of Biscay in 2005. Although the effects of managing the fishing activity with TACs, fees, taxes and ITQs on the stocks and future net profits are well documented in the specialized literature, scarce attention has been paid to analyze the effects of moratoriums on fisheries and the profitability of the fleet. This paper studies if the anchovy moratorium had a significant impact on the economic profitability of the fleet that fishes anchovy and other pelagic species in the North Atlantic waters. For this purpose, we compare the financial situations of the fleet before and after the moratorium from a statistical point of view using bootstrap, which is a flexible non-parametric and computationally intensive methodology. The results reveal the existence of a structural change in the financial performance of the fleet after the implementation of the moratorium. [Copyright &y& Elsevier]

This study explores the usefulness of a frame-based modelling approach in the southern Benguela upwelling ecosystem, with four frames describing observed small pelagic fish dominance patterns. We modelled the dynamics of sardine Sardinops sagax and anchovy Engraulis encrasicolus populations under the influence of the small pelagic fishery and climate variability, performed extensive sensitivity analyses and exercised the model prototype in scenarios based on realistic management objectives. Model outputs were seen to roughly parallel observed dynamics. Frame dynamics were reasonably sensitive to frame switching rules. Reduced sardine recruitment in the 'low' frames had a strong negative impact on stock recovery, and bycatch of juvenile sardine from the modelled anchovy fishery could also greatly impair sardine recovery. Specific tests included exploring the robustness of fisheries management strategies under highly stochastic recruitment and uncertainty around long-term environmental forcing. The respective frame of the model is suggested as a composite indicator of ecosystem state. The model approach shows promise for evaluating small pelagic fisheries management strategies in an ecosystem context incorporating long-term environmental variability. [ABSTRACT FROM AUTHOR]

Abstract: Recent changes in sea level of the Caspian Sea and ecological impacts caused by the invasive ctenophore (Mnemiopsis leidyi) have altered the ecosystem. A consequence is the changes in the absolute and relative abundance of the commercially important anchovy kilka (Clupeonella engrauliformis) in Iranian waters. To adjust to this change more rigorous management of this fishery is required. This paper examines the maximum sustainable yield (MSY) and fishing intensity at MSY. The paper presents estimates of f MSY, yield-per-recruit and spawning biomass-per-recruit under various harvest strategies of F max, F 0.1 and F 40%. We propose a method for estimating acceptable biological catch (ABC) that accounts for large differences in the quality and quantity of information and available data. The MSY and f MSY were estimated 44,652mt (metric tons) and 18,609 vessel×nights (a unit of effort). The ABC was estimated at 2190mt in 2004. In 2005, however, the catch of anchovy kilka was about 4300, over twice the estimated ABC. In 2008 (from January to October) the catch declined to 220mt. The analyses indicate that overfishing, especially between 2005 and 2008, is the main reason of the collapse of anchovy kilka in the Caspian Sea. [Copyright &y& Elsevier]

Fish recruitment is the result of the integration of small-scale processes affecting larval survival over a season and large oceanic areas. A hydrodynamic model was used to explore and model these physical–biological interaction mechanisms and then to perform the integration from individual to population scales in order to provide recruitment predictions for fisheries management. This method was applied to the case of anchovy ( Engraulis encrasicolus) in the Bay of Biscay (NE Atlantic). The main data available to investigate survival mechanisms were past growth (otolith) records of larvae and juveniles sampled at sea. The drift history of these individuals was reconstructed by a backtracking procedure using hydrodynamic simulations. The relationships between (real) growth variation and variations in physical parameters (estimated by hydrodynamic simulations) were explored along the individual trajectories obtained. These relationships were then used to build and adjust individual-based growth and survival models. Thousands of virtual buoys were released in the hydrodynamic model in order to reproduce the space–time spawning dynamics. Along the buoy trajectories (representative of sub-cohorts), the biophysical model was run to simulate growth and survival as a function of the environment encountered. The survival rate after 3 months of drift was estimated for each sub-cohort. The sum of all these survival rates over the season constituted an annual recruitment index. This index was validated over a series of recruitment estimations. The modelling choices, model results and the potential use of the recruitment index for fisheries management are discussed. [ABSTRACT FROM AUTHOR]

Plagányi, É. E., Rademeyer, R. A., Butterworth, D. S., Cunningham, C. L., and Johnston, S. J. 2007. Making management procedures operational — innovations implemented in South Africa. – ICES Journal of Marine Science, 64: 626–632.Operational management procedures (OMPs) have become an indispensable fisheries management tool in South Africa in light of their ability to consider the consequences of the main sources of assessment uncertainty. An overview is provided of the MP approaches applied to the major South African fisheries for hake, sardine and anchovy, and west coast rock lobster. As these are among the first OMPs to be implemented worldwide, some for periods longer than 10 y, they provide useful examples of some of the successes and problems encountered with the approach. Particular emphasis is given to some recent innovations and adaptations. These include moves to (i) joint two-species OMPs for the hake and sardine/anchovy resources; (ii) a reference set of weighted operating models for primary testing and tuning in preference to a single model; (iii) consideration of a “research-conditional” approach for hake to allow greater catches in the short term, conditional on research being implemented to resolve a key uncertainty; and (iv) incorporation of some ecosystem considerations by developing appropriate robustness tests (which link with moves towards an ecosystem approach to fisheries). Key lessons gained from experience over the past decade of OMP implementation in South Africa are summarized. [ABSTRACT FROM PUBLISHER]

De Lara, M., Doyen, L., Guilbaud, Th., and Rochet, M-J. 2007. Is a management framework based on spawning-stock biomass indicators sustainable? A viability approach. – ICES Journal of Marine Science, 64: 761–767: 000–000. Fisheries management agencies have to drive resources on sustainable paths, i.e. within defined boundaries for an indefinite time. The viable-control approach is proposed as a relevant method to deal with sustainability. We analyse the ICES precautionary approach (PA) by means of the notion of viability domain, and provide a mathematical test for sustainability. It is found that the PA based on spawning-stock biomass (SSB) and fishing mortality (F) indicators is sustainable only when recruits make a significant contribution to SSB. In this case, advice based upon SSB, with an appropriate reference point, is sufficient to ensure sustainability. In all other cases, SSB is not a sufficient metric of stock productivity and must be complemented with other management indicators to ensure sustainability. The approach is illustrated with numerical applications to the northern hake and Bay of Biscay anchovy. [ABSTRACT FROM PUBLISHER]

Many marine systems are subject to high nutrient loadings together with invasions by exotic species. Devising appropriate management responses is an increasing concern and one that has received relatively little attention from researchers. This paper considers the Black Sea anchovy fishery, which has benefited from the relaxation of a nutrient constraint, but has suffered from competition and predation by an invading comb-jelly (Mnemiopsis leidyi). We examine alternative hypotheses about the mechanism triggering outbreaks of the invader (sea temperatures versus nutrients), and the severity of these outbreaks, to see whether a constant escapement policy might be optimal for this fishery. If nutrient levels serve as the triggering mechanism, we argue a mixed blessing effect may be present, so that the effects of nutrient abatement for the anchovy fishery are uncertain. We specify our model empirically and show that a constant escapement policy would be viable under a scenario of reduced impacts from outbreaks of the invader and that nutrient abatement could be beneficial if nutrients trigger outbreaks. [ABSTRACT FROM AUTHOR]

Pilchard (sardine) and anchovy are the main targets of South Africa''s pelagic fishery. This fishery is the country''s second most valuable in monetary terms, and produces the highest annual yield in terms of landed mass (in recent years, a combined catch of the order of 400 000t). It is the most dynamic of South Africa''s main commercial fisheries, because the species targeted are relatively short-lived, often occur in mixed shoals, and experience large fluctuations in abundance. Mixed shoaling causes operational problems for the fishery, because of the inevitability of juvenile pilchard bycatch (of more value as adults for canning) in the anchovy-directed fishery. This operational interaction implies a trade-off between allowable catches for the two species, and hence necessitates that they are managed together. The development of a joint “management procedure” (sensu IWC) for the two species is described. This provides a framework for quantifying this trade-off, subject to the constraint that acceptable levels of risk of “collapse” are not exceeded for either resource. Important new features incorporated in a revision of the procedure implemented in 2002, which have made appreciably enhanced catches from the resources possible, are described. [Copyright &y& Elsevier]

As the world's marine ecosystems deteriorate due to pollution and overfishing, there is an urgent need to investigate links between the two problems. We assess the effects of improving environmental quality in the presence of such linkages, recognizing that the impact of pollution on fisheries may be complex and that efficiency benefits from pollution control may be limited in open-access fisheries. Using a dynamic bioeconomic modeling approach, we incorporate habitat quality in the presence of ecological 'regime shifts' and analyze the comparative static effects of an exogenous reduction in nutrient inputs. We apply the approach to the Black Sea anchovy fishery, where the introduction of an exotic comb jelly caused the 'regime shift.' We show that pollution abatement significantly raises catch, employment, and revenues at the long-run equilibrium of the system, but only if abatement prevents the regime shift. Ultimately, for substantial efficiency benefits to arise from nutrient abatement, the open-access problem must be addressed as well. [ABSTRACT FROM AUTHOR]

The management of small pelagic fisheries is a complex task due to its large variability of both environmental and biological processes. This high variability can impact the reliability of stock assessment models and fishery management recommendations. When this occurs, management decisions should explore alternative control rules based on empirical abundance indices or pragmatic management procedures. In this paper, we examined the performance of a harvest control rule (HCR) for the Chilean fleet in the shared Chile-Peru anchovy (Engraulis ringens) fishery (16°S–24°S), which is one of the most important stocks in the Humboldt marine ecosystem in the Southeast Pacific. The HCR uses the annual changes in spawning biomass estimated by Daily Egg Production Method (DEPM) surveys in the waters off northern Chile. Analyzes are carried out through operating models simulating population regime shifts under different uncertainty sources. The results show that despite the latent risk of overfishing caused both by recruitment variability and the lack of fisheries management coordination between two jurisdictions, the control of one of the parties' fishing mortality can enable the sustainability of the entire stock, provided the fishing effort of the other jurisdiction be remained at similar levels as in the last decade. The use of an HCR would avoid increases in fishing mortality and would facilitate B MSY -based management goals. This research determined conditions under which the shared Chile-Peru anchovy fishery can be sustainable considering different sources of uncertainty of the biological-fishing system. [ABSTRACT FROM AUTHOR]

Management procedures (MPs) have been used to regulate two major South African fisheries (the demersal hake fishery and the pelagic fishery for sardine and anchovy) since the early 1990s and are currently undergoing revision, while new MPs have recently been adopted for the South African west coast rock lobster fishery and Namibian hake and seal fisheries. The development and revision of these MPs are summarized in this paper, in particular with regard to their robustness to key uncertainties. The most notable common advantage of the use of an MP approach in these five fisheries has been to render the process of providing scientific total allowable catch recommendations more transparent, thus enhancing credibility between fishery scientists and members of industry. [ABSTRACT FROM PUBLISHER]

We apply the Fishery Performance Indicators (FPIs) methodology to the Southeast Pacific Anchoveta Fishery off southern Peru and northern Chile. Our basic model of analysis is a production function framework, where the performance outcomes are a result of the available inputs. We measured all FPI categories (outcomes and input metrics) and then grouped the metrics into different dimensions suitable for analysis. We obtained the value of each metric from different sources using expert evaluation and secondary information. Then we calculated aggregated measures at the country level and for the total fishery. We compared the country results and tested for mean differences. Our results suggest that there are no significant differences between the Chilean and Peruvian fisheries in terms of inputs. Moreover, no differences between the fisheries branches were found in the post-harvest stage. In the harvest stage, however, the Chilean fishery performs better than the Peruvian. From the differences and similarities found, we discuss the performance results between the Peruvian and Chilean branches of the fishery. The differences we found seems to be due to general societal factors that are beyond the control of fisheries managers. The differences in the organization of the fishery, characterized by high levels of concentration and vertical integration in the Chilean branch, could also explain the observed gap in performance. ● The FPIs methodology is applied to the Southeast Pacific Anchoveta Fishery off southern Peru and northern Chile. ● Our model of analysis is a production function, where the performance outcomes are a result of the available inputs. ● We measured all FPI outcomes and input metrics and then grouped them into different dimensions for analysis. ● We calculated aggregated measures at the country level and for the total fishery. ● We compared the country results and tested for mean differences. ● Our results suggest that there are no differences between the Chilean and Peruvian fisheries in terms of inputs. ● In the harvest stage, however, the Chilean fishery performs better than the Peruvian. ● We discuss the performance results between the Peruvian and Chilean branches of the fishery. ● The differences seems to be due to general societal factors that are beyond the control of fisheries managers [ABSTRACT FROM AUTHOR]