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Better data collection in shark fisheries – Learning from practice












FAO. 2021. Better data collection in shark fisheries – Learning from practice. FAO Fisheries and Aquaculture Circular No. 1227. Rome. 




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    Book (series)
    Management techniques for elasmobranch fisheries. 2005
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    This publication describes the scientific principles and techniques used for resource management of elasmobranch fisheries with emphasis on the particular context of elasmobranchs. The management characteristics of these fishes are described – their common bycatch character and their biological constraints on productivity (low growth rate, late maturity and low fecundity). Stock assessment of elasmobranchs is described in the context of management objectives in a wide management contex t. Special attention is given to accurate species identification given the prevalent aggregating of landings data across species, genera and often families in this group. Techniques and experiences for tagging elasmobranchs for population estimation are described as well as methods of genetic techniques for stock identification. Methods and problems involved in determining age, growth, fecundity and mortality rates are described and their use in age-structured models within the conte xt of the reproductive biology of these fishes. Demographic models to determine the productivity of elasmobranch resources are described. Use of surveys to complement information derived from fisheries is described together with management measures. Last, practices of shark utilization are noted.
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    Book (series)
    Elasmobranchs of the mediterranean and black sea: status, ecology and biology, biographic analysis 2012
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    The authors have compiled published information on taxonomy, distribution, status, statistics, fisheries, bycatch, biologic and ecologic parameters on age and growth, food and feeding habits, reproductive biology and stock assessment of elasmobranchs in the Mediterranean and Black Sea. This bibliographic analysis, through 661 papers dealing with elasmobranchs in the GFCM area, shows that cartilaginous species, including sharks, rays and chimaeras, are by far the most endangered group of marine fish in the Mediterranean Sea, with 31 species (40 percent of all) critically endangered, endangered or vulnerable. The biological characteristics of elasmobranchs (low fecundity, late maturity, slow growth) make them more vulnerable to fishing pressure than most teleost fish. Overfishing, wide use of non-selective fishing practices and habitat degradation are leading to dramatic declines of these species in the Mediterranean Sea. In general, elasmobranchs are not targeted but are caught incidentally. In many fisheries they are, however, often landed and marketed. The study also highlights the following points: – Works are concentrated mainly in the western Mediterranean. Few works concern endangered species and those of the GFCM priority list; – Much systematic confusion persists for some species and some others are doubtful; – The IUCN red list shows clearly the vulnerability of elasmobranchs and the lack of data; – A decline in cartilaginous fish speci es landings has been observed while fishing effort has generally increased; – A standardization of methods and expression of results on the biology should be generalized in the whole Mediterranean; – Papers on biologic parameters concern few species primarily in the occidental and central Mediterranean areas. Therefore, recommendations to fill gaps in order to protect and manage elasmobranchs stocks are proposed in this document. In fact, better understanding of the composition of incidental and targeted catches of sharks by commercial fisheries and biological and ecological parameters are fundamentally important for the conservation of these populations. Moreover, problems encountered by elasmobranchs in the GFCM area are highlighted and conservation measures are suggested.
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    Meeting
    Report of the Ninth Session of the IOTC Working Party on Ecosystems and Bycatch 2013
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    The Ninth Session of the Indian Ocean Tu Commission‘s (IOTC) Working Party on Ecosystems and Bycatch (WPEB) was held in La Reunion, France, from 12 to 16 September 2013. A total of 32 participants (48 in 2012) attended the Session. The meeting was opened by Mr Ludovic Courtois, Secrétaire général du Comité régiol des pêches maritimes et des élevages marins (CRPMEM) de La Réunion, who welcomed participants to La Reunion and formally opened the Ninth Session of the IOTC Working Party on Ecosystems and Bycatch. The Chair, Dr. Charles Anderson also subsequently welcomed participants to La Reunion, including the Invited Expert, Dr. Ronel Nel, from the Nelson Mandela Metropolitan University, Port Elizabeth, South Africa. Employment of a Fisheries Officer NOTING the rapidly increasing scientific workload at the IOTC Secretariat, including a wide range of additiol duties on ecosystems and bycatch assigned to it by the SC and the Commission, and that the new Fishery Officer (Science) supporting the IOTC scientific activities has not been given a mandate by the Commission to work on ecosystems and bycatch matters, the WPEB strongly RECOMMENDED that the Commission approve the hiring of a Fishery Officer (Bycatch) to work on bycatch matters in support of the scientific process. (para.12) Regiol observer scheme The WPEB RECOMMENDED that the Compliance Committee and Commission consider how to address the lack of implementation of regiol observer schemes by CPCs for their fleets and reporti ng to the IOTC Secretariat as per the provision of Resolution 11/04 on a Regiol Observer Scheme, noting the update provided in Appendix VI. (para.35) The WPEB RECOMMENDED that as a priority, the IOTC Secretariat should immediately commence work with CPCs that are yet to develop and implement a Regiol Observer Scheme that would meet the requirements contained in Resolution 11/04, and provide an update at the next session of the WPEB. (para.37) Training for CPCs having gillnet fleets on species id entification, bycatch mitigation and data collection methods and also to identify other potential sources of assistance – Development of plans of action The WPEB RECOMMENDED that the Commission allocate funds in its 2014 and 2015 budgets for the IOTC Secretariat to carry out training for CPCs having gillnet fleets on bycatch mitigation methods, species identification, and data collection methods (budget estimate: Table 4). (para.64) Ecological Risk Assessment: review of current knowledge and pot ential magement implications The WPEB RECOMMENDED that the Commission note the list of the 10 most vulnerable shark species to longline gear (Table 7) and purse seine gear (Table 8) in the Indian Ocean, as determined by a productivity susceptibility alysis, compared to the list of shark species/groups required to be recorded for each gear, contained in Resolution 13/03 on the recording of catch and effort by fishing vessels in the IOTC area of competence. At the next revision to Resolution 13/03 , the Commission may wish to add the missing species/groups of sharks and rays. (para.123) Review of data needs and way forward for the evaluation of shark stocks NOTING that Resolution 10/02 mandatory statistical requirements for IOTC Members and Cooperating Non- Contracting Parties (CPC's), makes provision for data to be reported to the IOTC on ?the most commonly caught shark species and, where possible, to the less common shark species?, without giving any list defining the most common and le ss common species, and recognising the general lack of shark data being recorded and reported to the IOTC Secretariat, the WPEB RECOMMENDED that Resolution 10/02 is revised in order to include the list of most commonly caught elasmobranch species (Table 10) for which nomil catch data shall be reported as part of the statistical requirement for IOTC CPCs. (para.138) Review of Resolution 12/04 on the conservation of marine turtles The WPEB RECOMMENDED that at the next revision of IOTC Resolution 1 2/04 on the conservation of marine turtles, the measure is strengthened to ensure that where possible, CPCs report annually on the total estimated level of incidental catches of marine turtles, by species, as provided at Table 12. (para.168) Resolution 10/02 Mandatory statistical [reporting] requirements for IOTC Members and Cooperating Non- Contracting Parties (CPCs) NOTING that Resolution 10/02 does not make provisions for data to be reported to the IOTC on marine turtles, the WPEB RECOMMENDED that Resolution 10/02 is revised in order to make the reporting requirements coherent with those stated in Resolution 12/04 on the conservation of marine turtles and Resolution 13/03 on On the recording of catch and effort by fishing vessels in the IOTC area of competence. (para.169) Format of future WPEB Sessions The WPEB RECOMMENDED that the SC note the following: (para.253) ? The WPEB DISCUSSED the future format in order to focus the efforts of scientists working on different groups of bycat ch species to address more efficiently, the mandate of the group. ? The WPEB CONSIDERED a range of options which the SC is asked to consider: o Option 1: The current WPEB be split into two; A dedicated Working Party on Sharks (WPS) and a Working Party on Ecosystems and Bycatch (WPEB). o Option 2: Retaining the WPEB in its current form, with alterting focus of sharks in one year, followed by other ecosystem and bycatch issues in the next year. o Option 3: Maintaining the WPEB with clear guideline s to deal with sharks every year, as well as other issues and bycatch groups in alterte years or as required. ? The WPEB AGREED that shark issues were important to address on a yearly basis. Election of a Chairperson and Vice-Chairperson for the next biennium The WPEB RECOMMENDED that the SC note the new Chairperson, Dr. Rui Coelho (EU,Portugal) and Vice- Chairperson, Dr. Evgeny Romanov (La Réunion), of the WPEB for the next biennium. (para.263) Report of the Ninth Session of the Working Party o n Ecosystems and Bycatch The WPEB RECOMMENDED that the Scientific Committee consider the consolidated set of recommendations arising from WPEB09, provided at Appendix XXI, as well as the magement advice provided in the draft resource stock status summary for each of the seven shark species, as well of those for marine turtles and seabirds: (para.265) Sharks o Blue sharks (Prioce glauca) – Appendix X o Oceanic whitetip sharks (Carcharhinus longimanus) – Appendix XI o Scalloped hammerhead sharks ( Sphyr lewini) – Appendix XII o Shortfin mako sharks (Isurus oxyrinchus) – Appendix XIII o Silky sharks (Carcharhinus falciformis) – Appendix XIV o Bigeye thresher sharks (Alopias superciliosus) – Appendix XV o Pelagic thresher sharks (Alopias pelagicus) – Appendix XVI Other species/groups o Marine turtles – Appendix XVII o Seabirds – Appendix XVIII A summary of the stock status for some of the most commonly caught shark species caught in association with IOTC fisheries for tu and tu-like species is provided in Table 1.

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