Review of fisheries data collection systems in BOBLME countries

The review focuses on small pelagics, Hilsa shad and Indian Mackerel in particular, with the exception of the Maldives, but the findings are generally applicable to national systems of data collection. Recommendations are given for each country

Cape Verde coastal ecosystem: a study of community structure, trophic interactions and exploitation pattern

Tese de dout., Ciências e Tecnologia das Pescas, Faculdade de Ciências do Mar e do Ambiente, Universidade do Algarve, 2005A mass-balance trophic model was created to describe the coastal ecosystem of the Cape Verde Archipelago for the time period from 1981 to 1985, using available estimates on biomass and catches. This time period was characterised by predominantly artisanal fisheries and a low level of motorisation; the initial phase of a more intensive fishery development. Subsequently, a dynamic simulation model, using Ecopath with Ecosim, was used to simulate from 1986 to 2000, incorporating time series information on biomass, catches and catch per unit of effort (CPUE). Using this approach, a number of problems were detected in model specification such as incompatible biomass estimates for small pelagics and various demersal fish groups. Measures of fishing effort in fishing days or trips were found to be unreliable, in particular for the artisanal fishery. Available biomass estimates for small pelagic resources from acoustic surveys were questionable. Conventional biomass dynamic modelling was therefore applied to estimate biomass of small pelagics and provide indications for management purposes, including parameter estimation and risk assessment using the frequentist and Bayesian approaches. After a number of adjustments applied to the initial model, the approach used in simulation was to fit the model to observed catch estimates by adjusting effort, placing less emphasis on fitting to CPUE and biomass estimates. A reasonable overall fit to time series of catches was obtained for 18 fish groups, using only two overall trends for artisanal and industrial effort and three specific trends for small pelagics, yellowfin, and skipjack, which are the main targets of the indutrial fisheries. The observed decrease in abundance of important predators such as yellowfin and skipjack tuna resulted in decreased predation on neritic pelagic species and some demersal fish groups, but this was compensated by higher fishing mortality over the study period. Consequently, the model estimated an almost constant biomass of neritic fish species from 1986 to 2000. Overall fish biomass decreased by 10 percent, including pelagic migratory species. Relative fishing effort was assumed to have almost tripled over the time period from 1986 to 2000 (effort directed towards small pelagics was assumed to have increased by a factor 5), but this resulted in only a 19 per cent increase in catches. Thus, previous assessments of potential fish harvest, ranging from 25 000 to 58 000 tonnes, appear to have been overly optimistic. Alternative methodologies were applied to assess the fishery resources in Cape Verde in order to gain further understanding on the dynamics of the system and the effects of fishing over time as well as to validate the results of ecosystem modelling. This included nonparametric multidimensional scaling (MDS), generalized linear models (GLM), size spectra analysis, and a type of time series analysis (MAFA). The changes observed over time in the size structure and species composition/abundance of demersal fish communities were slight or even negligible. There was a tendency for lower abundance of demersal fish in recent years, but a decreasing trend was not apparent. It is however important to note that these iv results were based on trawl survey data, which concern a limited area of trawlable grounds in Cape Verde. In contrast, time series analysis of catch data indicates that a shift has occurred with decreasing catches of important pelagic species such as yellowfin and skipjack tuna and increasing catches of small pelagics and neritic tuna as well as some demersal species. Simulation with Ecosim gave similar results as they were based on the same catch data, but this is nevertheless reassuring as alternative methods gave consistent results. We believe that this study has been successful in taking the first steps towards an ecosystem approach to assess the effects of fishing in Cape Verde, but further research is necessary to resolve some crucial issues such as the conflicting results on demersal fish biomass and the possible over-exploitation of demersal predators and moray eels. Priority should also be given to the definition of fleet components, effort and CPUE estimation, and the study of increasing efficiency, using the available catch and effort data.Fundação para a Ciência e a Tecnologi

Evaluation of the governance structures of the cases

This report contains an evaluation of the governance structures of the EU long-distance fishing fleet in the six case studies of the FarFish project. These case studies include two high seas fisheries and four fisheries that are based on Sustainable Fisheries Partnership Agreements (SFPAs) between the EU and coastal states. All of these fisheries are important for the fishing fleets of multiple EU countries or respond to the priorities of Regional Fisheries Management Organisations (RFMOs) and the Common Fisheries Policy (CFP). The report focuses on different aspects of both the structural and actor conditions, in particular focusing on monitoring, control and surveillance (MCS) of the EU external fishing fleet. For each of the four SFPAs, we present the requirements set within the SFPAs, the legal framework and systems for MCS in the coastal state and their capacity. For the high seas cases, we present the governing framework of the area where such is in place and the practice of managing the EU fleet. For all cases, challenges of and measures to mitigate by-catch and discard issues and IUU fishing are presented. Lastly, we summaries the main findings regarding both achievements and identified challenges for the six case studies. This report is based on available data and synthesizes already existing information. It will function as a primer for further studies in the FarFish project of the governance structure of the EU fisheries outside Europe

Report on biological and ecological data in FFDB pilot version 1

Task 2.3 of work package 2 (Advancing biological knowledge and evaluation of current stock assessment models) focuses on the compilation of biological, ecological and fisheries dependent and fisheries independent data that is required for other FarFish WPs. During the first year of FarFish, some modifications in the objectives occurred, resulting in changes in the species. For example, in the Cape Verde and Seychelles CSs, the focus is now on by-catch species that are not assessed by the Regional Management Fisheries Organizations (RMFO): the International Commission for the Conservation of Atlantic Tunas (ICCAT) and the Indian Ocean Tuna Commission (IOTC). Lists of species for each CS have now been drawn up, sources of data identified, contacts have been made with RMFOs and DG MARE, and data is being compiled. Data compilation has been largely driven by the FarFish Data Base (FFDB) template developed in WP 6 (see deliverables D6.1 and D6.4). On the other hand, other data required for visualization purposes, especially time series, is also being compiled or requested. A formal data request is being prepared for DG MARE, while coastal state CS participants will be requested to provide data for the FFDB. Talks are also ongoing with RFMOs, especially CECAF, regarding data acquisition and how FarFish can contribute or add value to assessment and management. Actions that need to be taken by Task 2.3 participants include the provision of data and uploading of data to the FFDB. Task 2.3 is ongoing (Report on biological and ecological data in FFDB pilot version 2, due in Month 26 (July 31, 2019)

Two fish in a pod. Mislabelling on board threatens sustainability in mixed fisheries

Accuracy in reporting captures is a key element to achieve fisheries sustainability. However, identification of the catches might be a challenge when two or more species are morphologically similar and caught jointly, like the mixed fisheries of black hakes in East Atlantic African waters. Black hakes (Merluccius senegalensis and M. polli) are tough to differentiate without previous training due to their high morphological resemblance. The two species are managed as a single stock, although the biological differences between them suggest the need of a separate management. In this study, a total of 806 black hakes were visually identified by fishers on deck of fishing vessels operating in Mauritania and Senegal waters, then assigned to a species by sequencing 450bp of the Mitochondrial Control Region. Comparing the results with visual identification we found 31.4% of the total catch were incorrectly labelled on board by the fishermen. The accuracy of the fishers' identification depended on the depth of capture and on fish size, larger individuals caught from deeper waters being more correctly assigned to M. polli. Mislabelling biased to M. polli suggests that M. senegalensis, already catalogued as endangered, is being underreported, which could endanger the conservation of this species and threaten the sustainability of black hake fisheries. Our results highlight the need for separate evaluation of the stocks in mixed fisheries for morphologically similar fish. Thus, monitoring through DNA barcoding in the very first step of the seafood chain surveys would improve accurate species delimitation and reduce its impact on the correct assessment of the stocks.info:eu-repo/semantics/publishedVersio

Assessing mackerel scad, Decapterus macarellus, in Cape Verde: using a Bayesian approach to biomass dynamic modelling in a data-limited situation

The fisheries for mackerel scad, Decapterus macarellus, are particularly important in Cape Verde, constituting almost 40% of total catches at the peak of the fishery in 1997 and 1998 ( 3700 tonnes). Catches have been stable at a much lower level of about 2 100 tonnes in recent years. Given the importance of mackerel scad in terms of catch weight and local food security, there is an urgent need for updated assessment. Stock assessment was carried out using a Bayesian approach to biomass dynamic modelling. In order to tackle the problem of a non-informative CPUE series, the intrinsic rate of increase, r, was estimated separately, and the ratio B-0/X, initial biomass relative to carrying capacity, was assumed based on available information. The results indicated that the current level of fishing is sustainable. The probability of collapse is low, particularly in the short-term, and it is likely that biomass may increase further above B-msy, indicating a healthy stock level. It would appear that it is relatively safe to increase catches even up to 4000 tonnes. However, the marginal posterior of r was almost identical to the prior, indicating that there is relatively low information content in CPUE. This was also the case in relation to B-0/X There have been substantial increases in fishing efficiency, which have not been adequately captured by the measure used for effort (days or trips), implying that the results may be overly optimistic and should be considered preliminary. (c) 2006 Elsevier B.V. All rights reserved

Potential economic impacts of achieving good environmental status in Black Sea fisheries

The Marine Strategy Framework Directive (MSFD) mandates that European Union (EU) member states achieve Good Environmental Status (GEnS) based on an ecosystem-based approach to management. For commercial fisheries, the primary target under the MSFD is one of maximum sustainable yield. Of Black Sea riparian nations, only Romania and Bulgaria are EU member states. Focusing at the supranational level, we review institutions and instruments relevant to management of the Black Sea. The economic values of current fish catches are assessed, and the results of a recent analytical assessment of fish stocks are used to estimate potential future values based on maximum sustainable yields. In the Black Sea region, despite long-standing attempts to improve fisheries management, there remains a lack of effective regional cooperation. Evidence from the scenario analysis suggests that achieving GEnS would not have an undue negative impact on overall fishery sector incomes, and could, with appropriate investments in processing and marketing, deliver increased economic benefits for Black Sea countries. The ongoing policy debate between and within Black Sea coastal states needs to be extended to include recognition of the potential economic and social benefits of effective fisheries management. More work is required to assess returns on investment in interim management measures to deliver GEnS

Life history strategies of the squid,Illex illecebrosus,in the Northwest Atlantic

Time series (1965-1985) of Illex illecebrosus catch and morphometric data from the Northwest Atlantic were analysed to describe geographic variability in population structure. The areas studied were NAFO sub-areas 3 to 6, which range from Newfoundland to the northeastern USA shelf. Population components, reflecting seasonal spawning groups, were identified based on analysis of length frequency data. Components 3 and 4 represent two prominent life cycles: the summer spawners and winter spawners respectively. Components 1, 2, and 5 do not represent different life cycles, but result from the capacity to shift between life cycles by prolonging (or shortening) the life span. The presence of up to five components in the southern area illustrates a life history strategy involving protracted spawning and complex population structure. There was clear geographic variability in annual catch, with fluctuations being most extreme in the most northern area. Annual catch levels in all areas were significantly correlated with the abundance of the winter-spawning component, as represented by the number of squid within samples which belong to component 4. Population structure in the most northem area was simplest and catch levels therefore were most dependent on the highly migratory winter-spawning component. This leads to greater catch variability in the most northern area than in the other areas. The advantages of good feeding conditions may compensate for the risks associated with long-range migrations, especially recruitment failure. Life history strategies involving migratory and non-migratory population components limit the risk of recruitment failure. The overall resultant life history strategy for Illex illecebrosus is one that ensures survival of the species by stabilizing recruitment in at least one (southern) area through protracted spawning, complex population structure and interaction of spawning components. Time series (1965-1985) of Illex illecebrosus catch and morphometric data from the Northwest Atlantic were analysed to describe geographic variability in population structure. The areas studied were NAFO sub-areas 3 to 6, which range from Newfoundland to the northeastern USA shelf. Population components, reflecting seasonal spawning groups, were identified based on analysis of length frequency data. Components 3 and 4 represent two prominent life cycles: the summer spawners and winter spawners respectively. Components 1, 2, and 5 do not represent different life cycles, but result from the capacity to shift between life cycles by prolonging (or shortening) the life span. The presence of up to five components in the southern area illustrates a life history strategy involving protracted spawning and complex population structure. There was clear geographic variability in annual catch, with fluctuations being most extreme in the most northern area. Annual catch levels in all areas were significantly correlated with the abundance of the winter-spawning component, as represented by the number of squid within samples which belong to component 4. Population structure in the most northem area was simplest and catch levels therefore were most dependent on the highly migratory winter-spawning component. This leads to greater catch variability in the most northern area than in the other areas. The advantages of good feeding conditions may compensate for the risks associated with long-range migrations, especially recruitment failure. Life history strategies involving migratory and non-migratory population components limit the risk of recruitment failure. The overall resultant life history strategy for Illex illecebrosus is one that ensures survival of the species by stabilizing recruitment in at least one (southern) area through protracted spawning, complex population structure and interaction of spawning components