Shark Depredation and Unwanted Bycatch in Pelagic Longline

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Shark Depredation and Unwanted Bycatch in Pelagic Longline Fisheries were provided on the life status of sharks caught subsequent to the 1991 requirement that for finning to be practiced, the whole carcass had to be retained. If, as is reported, the 1991 requirement ‘effectively prevented them (the vessels) from retaining shark fins whilst in Australian waters’, then the high survival prospects (Moyes et al 2006) of post release sharks would obviously have contributed to there having been no apparent trend in abundance as a consequence of fishery impact (based on observed catch rate data in the five years subsequent to 1991). And in New Zealand where similar amounts of the same species were being caught and actually processed for their fins throughout the 10-year period, impact of this is thought to not have had a serious effect on shark stocks (Francis et al 2001). Over a period of approximately 10 years (1990s) Australia’s domestic longline fishery had the unrestricted option of utilizing all sharks, even just for their fins. Whether this has had any bearing upon present day shark catch rates is not known. Five species, great white, grey nurse, megamouth, green sawfish and Herbert’s nurse shark are prohibited take and of these there have been 5 grey nurse and one great white interaction recorded in pelagic longline fisheries in Australia. A1.6. Influence of International Initiatives on Domestic Shark Management Various international fisheries management initiatives have been influential or instrumental in subsequent national initiatives in Australia for improved fisheries management, including the management of shark bycatch. For example, the United Nations Food and Agriculture Organization produced the ‘Code of Conduct for Responsible Fishing’. In 1999, Australia ratified the United Nations Agreement for the Conservation and Management of Straddling Fish Stocks and Highly Migratory Fish Stocks, and became a party to the United Nations Convention on the Law of the Sea. Australia is a signatory to the Convention on International Trade in Endangered Species (CITES), which can mean an obligation in relation to particular shark species. Australia has produced a Shark Assessment Report (SAR), a requirement of member nations in response to the Food and Agriculture Organization of the United Nation’s International Plan of Action on sharks. The SAR identifies conservation and management issues associated with shark catch, the most significant of which are those including target, by product and bycatch. There were 24 priority requirements identified. They included better recording of all shark catches, protection of species with poor conservation status, cross jurisdictional management of stocks, national controls on shark finning, the need to develop shark bycatch reduction methods, handling practices of returned catch, ecosystem effects of shark management practices (specifically trophic cascade), impact of increased shark populations, impact of prey removal and the impact of market demand on shark populations. Australia’s management of the practice of shark finning is also consistent with its obligation to the United Nations Food and Agriculture Organizations Code of Conduct for Responsible Fisheries to fully utilize bycatch and by product species. This practice is reiterated to signatory nations to the FAO IPOA sharks, in that incidental shark capture should not result in waste, and capture of non-utilized species should be minimized. Australia is also a member of Regional Fisheries Management Organizations such as the Indian Ocean Tuna Commission (IOTC) and the Commission for the Conservation of Southern Bluefin Tuna (CCSBT) under which shark bycatch management specifically can be further addressed. For instance, within such processes, Australia entered into a Bilateral Shark Bycatch Code of Practice agreement with Japan, the objective being to ensure all sharks taken are either: released alive and undamaged (i.e. not mutilated or cut prior to release), or retained whole, not just fins and killed first before being processed. A1.7. National Management Processes for Sharks in Australia Commonwealth fisheries bycatch is managed by several procedures such as by a direction and/or a specific inclusion within a statutory Management Plan, as a condition or a bycatch regulation prescription of a fishing permit, through an urgent temporary order or as a prohibition against the take of a particular species in the Fisheries Act. Increasing catches of sharks and the inherently low productivity of sharks are the reasons for concern, not just in Australia but also worldwide for populations of some shark species. But, the relatively low market value of sharks is considered to have been the reason why few countries have managed shark catch in the past (SAG and Lack, 2004). Without appropriate management in place to prevent or at least contain increased exploitation potential, today’s bycatch (discarded sharks) can become a by-product tomorrow as determined by a changing market demand. From a scientific perspective, management of pelagic sharks is complicated by the unknown effects on the oceanic ecosystems of removing large number of these top predators. Also, because sharks have historically been of low economic value in most countries, data quality has been poor. The above situation precipitated development of the International Plan of Action for the Conservation and Management of Sharks (FAO 1999), to which Australia responded by establishing a Shark Advisory Group in 2000 for the purpose of developing a shark assessment report which was released in 2001 (Rose and SAG 2001). This report highlighted the necessity for development of an Australian Shark-plan (SAG and Lack 2004) ‘to ensure the conservation and management of shark resources and their ecologically sustainable use’. Specifically related to fisheries impacts, the main objectives of the plan were to ensure sustainability of target and non-target catches, to minimize incidental catches of sharks that are not being utilized and for those that are utilized, minimize waste such as when fins only from the shark are retained, in accordance with article 7.2.2 of the Code of Conduct for Responsible Fishing (FAO 1995). The NPOA–sharks provides a guide to incorporating shark conservation and management issues into the various fisheries management plans. It recommends examining the methods used to manage and reduce shark by-catch. The pelagic longline fishery was identified as a potential source of significant shark catches and attempts have been made to evaluate 40
Australia Longline Tuna and Billfish Fishery this in order to develop a management response. Hobday et al (2004) undertook an ecological risk assessment of the main portion of this fishery in Australia. The fishery now operates under management plans, the performance of which must be assessed at least every 5 years (AFMA 2005). Under the management plan, a bycatch action plan (AFMA 2004) must be prepared, and implemented and for as long as it is in force it must be reviewed at least once every second year. The management plan also stipulates that ecological sustainability of each primary species and secondary species in the fishery be assessed and reference points established (precautionary limits must otherwise be set) within 24 months of the plan’s commencement day. This is consistent with the primary objective of fisheries management here (in Australia): to maintain an ecologically sustainable harvest rate of target, by-product and by-catch species. After the policy mandate for management of fishing impact on non-target species (MCFFA 1999) a bycatch policy was adopted (commonwealth of Australia 2000). Sharks under the management plan are referred to as secondary species where they are considered by-product with a 20 carcasses per trip limit, after which they are bycatch and any subsequently caught must not be retained. This trip limit was imposed as a precautionary response under the Fisheries Management Regulations 1992 to high market value of shark fins and the largely unknown status of shark stocks. The measures in the Management Plan aim to minimize the impact of the fishery on sharks by reducing the levels of bycatch and the incentive for targeting of shark species generally, including on the high seas by Australian vessels. Shark bycatch issues highlighted by SAG and Lack (2004) that are most relevant to pelagic longline fisheries were the need to reduce or eliminate shark by-catch, shark handling practices, the necessity for all dead sharks to be fully utilized and reliable assessment made of catch rates and the extent of utilization (fate of bycatch). Barker and Schluessel (2004) highlight the complications of managing oceanic, highly migratory species, an issue also identified in SAG and Lack (2004) with some initiatives proposed whereby shark stock shared with other nations may be managed. The Southern Shark and South East Non-trawl Fishery Bycatch Action Plan (2001) and The Commonwealth Policy on Fisheries Bycatch Commonwealth of Australia (2000) both refer to bycatch being that part of the catch which is discarded, or which interacts with the fishing gear but does not reach the deck but the Commonwealth Policy on Fisheries Bycatch does not include by-product under its definition of bycatch. By-product is the part of catch kept or sold that was not a prime target species. This is managed in a similar manner to target catches under various management plans, fishing permit conditions etc. Such fisheries-specific management processes can be, and have been dictated by broader processes such as Australia’s Oceans Policy (Commonwealth of Australia 1998) as well as its Environment Protection and Biodiversity Conservation Act 1999 (EPBC Act). The EPBC Act for instance dictates that if a species of shark is nationally threatened then apart from the requirement that a recovery plan is prepared for that species, assessment and approval of the impacting process is required. The Oceans Policy provides a framework for marine planning and management including that of bycatch. All Commonwealth fisheries are being strategically assessed under the EPBC Act, supposedly by 2005 and will include bycatch, which for any shark species that is protected will require that a suitable data collection scheme be in place to allow for risk assessment to be undertaken (Rose and SAG 2001). Of 47 species currently identified as species of concern (through the processes of the International Union for the Convention of Nature (IUCN) Red List, the EPBC Act, and the Endangered Species Scientific Sub-committee (ESSS), eleven of these are known to be caught in non-shark targeted fisheries. There are nine shark species specifically protected under legislation and a conservation status has been assigned to approximately 70 species. For two species, Grey Nurse and White Shark, Recovery Plans that have been prepared (Environment Australia 2000) and 2000a), do not identify pelagic longline fisheries as a problem. Of direct relevance to the actions and objectives of the current study SAG and Lack (2004) proposed that shark-bycatch reduction measures be assessed for effectiveness and or developed, and that adoption be encouraged of those that are effective. Australia’s tuna and billfish longline and minor line fisheries bycatch action plan (2004), reiterates the relevant management guidelines contained in the nations bycatch in fisheries policy (commonwealth of Australia 2000) and provides specific time-line related processes to ensure effective ongoing management of bycatch. Tools to facilitate management under such plans include specific gear usage and changes in fishing practices, move-on provisions, as well as seasonal and temporal closures (AFMA 2004). But in an Environmental assessment of Commonwealth fisheries, there is more generally a requirement that data collection, assessment and management responses are in place for target and by product species, bycatch, and the broader environment. These must be adequate to demonstrate that a commercial fishery is managed in an ecologically sustainable manner, and, a guiding principle for the ecological sustainable management of fisheries is for there to be no over-fishing, so that catch levels maintain ecologically viable stock levels. All the above processes have been necessary if only, in the absence of reliable shark catch rate and population dynamics data, to uphold the legislative objective that optimum utilization of living resources shall be achieved whilst ensuring adherence to the principles of ecological sustainability and the exercise of the precautionary principle. The eastern Tuna Billfish Fishery Industry Code of Practice for Responsible Fishing (Jusseit and Robinson 2003), as do similar Codes of Practice that have been developed for other sectors of the fishery, gives specific voluntary mitigation advice in relation to sharks. This includes not targeting them for fins, ensuring they are dead by severing the backbone behind the head before processing, utilizing all shark products by pursuing markets for these and for those that are released, to do this carefully so as to maximize their survival prospects including by removal of hooks and line when possible. The code also encourages fishers to provide comprehensive and accurate logbook information, an element lacking and one perhaps exacerbating concerns over the extent of shark bycatch and the species composition of this. 41
Page 3 and 4: Shark Depredation and Unwanted Byca
Page 5: Shark Depredation and Unwanted Byca
Page 9 and 10: Contents Summary and Conclusions 1
Page 11 and 12: Contents Appendix 3. Fiji Pelagic L
Page 13: Contents Appendix 8. USA Hawaii Lon
Page 19 and 20: Chapter 1 Introduction and Methods
Page 21 and 22: Introduction and Methods 1.2. Metho
Page 23 and 24: Fishing Gear and Operational Charac
Page 25 and 26: Fishing Gear and Operational Charac
Page 27 and 28: Shark Catch Rates and Disposition T
Page 29 and 30: Chapter 4 National and Internationa
Page 31 and 32: National and International Measures
Page 33 and 34: Economic, Practical, Ecological and
Page 35 and 36: Economic, Practical, Ecological and
Page 37 and 38: Chapter 6 Industry Attitudes and Pr
Page 39 and 40: Industry Attitudes and Practices Lo
Page 41 and 42: Industry Attitudes and Practices Fi
Page 43 and 44: Chapter 7 Potential of Deterrents,
Page 45 and 46: Potential of Deterrents, Hotspot Av
Page 47 and 48: References Campana, S.E., L. Marks,
Page 49: References Neves dos Santos, M., Ga
Page 99 and 100: Appendix 5 Japan Pelagic Longline F
Page 101 and 102: Japan Pelagic Longline Fisheries Fi
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Japan Pelagic Longline Fisheries Ta
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Japan Pelagic Longline Fisheries is
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Japan Pelagic Longline Fisheries ta
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Japan Pelagic Longline Fisheries In
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Japan Pelagic Longline Fisheries A5
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Appendix 6 Peru Artisanal Mahimahi
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Peru Artisanal Mahimahi And Shark L
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Appendix 7 South Africa Pelagic Lon
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South Africa Pelagic Longline Tuna
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Appendix 8 USA Hawaii-based Pelagic
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USA Hawaii-based Pelagic Longline S
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Appendix 9 USA Atlantic, Gulf of Me
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USA Atlantic, Gulf of Mexico and Ca
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Shark Depredation and Unwanted Bycatch in Pelagic Longline

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