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What information is needed to judge the basic health of a stock?

SESSION I: Comments on ‘Basic tools, Indicators, and Best Practices’ in the Bioeconomic context John F. Caddy (Consultant to WWF). What information is needed to judge the basic health of a stock?.

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What information is needed to judge the basic health of a stock?

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  1. SESSION I:Comments on ‘Basic tools, Indicators, and Best Practices’ in the Bioeconomic contextJohn F. Caddy(Consultant to WWF)

  2. What information is needed to judge the basic health of a stock? Sustaining exploitation rates near MSY depends on active management if a continuously productive resource is to be maintained. Improved fleet technology, high market demand, and environmental fluctuations make management very difficult if fleet capacity is already high! Achieving ‘sustainability’ is far from automatic! For example, my recent studies have demonstrated that: a) N. Atlantic landing trends for many species have shown ‘boom and bust’ characteristics (Caddy and Surette 2006); b) Restoring depleted fish stocks is painful and costly. Successful restoration plans so far have been rendered difficult by the harvest needs of high capacity fleets (Caddy and Agnew 2005) – i.e., don’t assume that stock depletion resulting from excess capacity is going to be easily reversible!

  3. The UN Summit’s Plan of Implementation (Article 30) stated that in order to achieve sustainable fisheries, it is necessary to set concrete objectives: viz: “Maintain or restore stocks to levels that can produce the maximum sustainable yield with the aim of achieving these goals for depleted stocks on an urgent basis and where possible not later than 2015.” (United Nations, 2002). A global review of stock recovery plans (Caddy and Agnew, 2004), found 58 cases in which a recovery effort had achieved some success – mainly in North American waters. Most recovery efforts have been very recent, and recovery times were between 4-8 years to 14-22 years – i.e., without a major effort towards conservation in the following decade, it will be difficult to achieve the UN objective.

  4. What are the best existing sources of data on stock abundance and fleet capacity? • A/ Data on stock abundance has been derived in two main ways: • indirectly from commercial catches (catch rate, size/age composition) • (more reliably?) by fishery surveys from at-sea platforms (e.g. research vessels). • - In either case, data must be collected and analysed by dedicated personnel following statistical procedures, and must include data from all fleets fishing the same stock, whatever nationality. • B/ A fleet registry is required, containing numbers of actively fishing/licensed vessels, & their characteristics (tonnage, hold capacity and fishing methodology). For shared stocks and international resources, the capacity of all fleets fishing the resource should be monitored. • To calibrate the ‘fishing power’ of commercial vessels against the harvest rate, a measure of fishing mortality is needed (from A/). Typically, such calibrations show that the experience accumulated by skippers, plus the effects of new technologies, increase the fishing power of a fleet by some 2-4%annually. The key problem for fishery management then, is how to keep fleet fishing power in check, since: • C/ For ‘mature’ fisheries, the fleet size often exceeds that needed to harvest the resource – in order to stay below or at MSY, a system of limited quotas means that vessels spend a significant part of a season tied up in port in order to avoid overfishing. • D/ Given a steady growth in fishing power, license replacement proceduresneed to be rigorously enforced, so that an old vessel of a given fishing power leaving the fleet is replaced by one of the same or lower fishing power.

  5. A science-based fisheries management system is information-intensive – it must measure inputs to the fishery as well as outputs. The classical developed -country approach is similar to the following figure:

  6. Advisable and usually achievable criteria for management? Criteria for collecting info are only adequateif: a) A long term management plan with objectives was decided and discussed with industry;b) Adequate funds are set aside for monitoring, assessment, MCS and management; c) Ideally, a management control rule should be in place which establishes what actions to take promptly if LRPs are overshot;d) Trained personnel are available to collect data, analyse it, and make management recommendations; e) The managers are able to understand the advice, and have in place a suitable regulatory framework and funds to enforce it.

  7. What global data bases on fisheries exist? • The FAO capture database, published in the FAO Yearbook of Fishery Statistics or its electronic equivalent (See FAO.org), is the most complete and widely used source on global catch trends, but low in resolution. Its accuracy depends on the quality (and impartiality!) of national data reporting to FAO: • FAO fishing areas are large and may include several stocks; i.e., its analysis may not be stock-specific; • - Catches of some species are included under the genus or higher taxonomic category; • deteriorating economic conditions, social unrest, famine, tsunamis etc, will result in a corresponding decline in monitoring capabilities; • Despite these points, the FAO biennial evaluation has proved consistent. • But it is debatable whether it is adequate on a stock-by-stock basis for WTO monitoring purposes, without substantial extra funding.

  8. How many fisheries are currently assessed? FAO (2006) reported on some 441 stocks for which the state of exploitation has been estimated, and some others where catch trends have been analysed. While this list includes most of the major stocks, many smaller resources are not regularly assessed; either by countries or fishery commissions. The situation cannot be too different world-wide – for example, the small tunas and tuna-like species of tropical areas are not usually assessed by tuna Commissions, even though these species are taken incidentally by industrial vessels, and are of key importance to inshore fleets.

  9. Can we use economic data to identify whether subsidies will be damaging? In theory, the balance sheet on costs and earnings of boats already in a fishery could be used to identify overfishing, and the need to avoid subsidies. However, low interest loans and their later write-offs are not uncommon and difficult to identify from the outside. If earnings are not being set aside for vessel replacement, perhaps this may diagnose a reliance on subsidies?

  10. Two main management options exist - almost always the second is chosen: • 1/ Harvest at significantly below the MSY level. To To keep spawning biomasses high and let slow-growing species replace themselves. Ancillary measures (e.g. closures, MPAs) may be used to protect critical habitats/ life history stages. • The information needs here are much less than for the next option: • 2/ Aim for a harvest rate close to, or at MSY. • Feed-back from indicators of biomass, spawning potential and annual recruitment is needed annually to regulate harvest rates. • Vessel fishing power may grow 2-4%/year (often undetected), hence fleet capacity must be controlled by strict vessel replacement rules; • A Management Control Rule must be quickly implemented when Limit Reference Points (LRPs) are infringed; • A management plan should set LRP’s; long-term limits for stocks and fleets; • The plan should include a stock recovery strategy once LRPs are infringed. • Option 2 is very information intensive!

  11. Are small-scale fisheries exempt from a responsibility for stock collapses? The assumption that small scale fisheries do not lead to overexploitation is not justified by the facts in several parts of the world. Evidence suggests that uncontrolled small-scale fishing/inappropriate gear, can result in ecological disasters – e.g. the trap fisheries in some Caribbean countries; the gill-net fishery in the northern Gulf of California (supposedly leading to dolphin by-catch and potentially their extinction), and a variety of inshore fisheries in Asian countries. (Subsidies to convert to less damaging, small scale methods are needed) In some coastal communities informal rules dictate local access rights, in a system of resource sharing. Such rules can be rendered ineffective if subsidies allow larger vessels to enter, and quota shares based on ‘historical performance’ ignore historical access rights of locals to local resources – Can subsidies be used to counteract ‘unfair?’ historical allocations?

  12. What are current trends in the availability of fishery data? Technological and ecological changes have made stock assessment procedures more complex (e.g. adding ecosystem criteria), and less precise since fishing power changes are costly and difficult to measure. Often this has has led to neglecting measurement of fleet fishing effort . Collecting biological data is also manpower intensive and costly if a dedicated research vessel is required, and current concerns with ‘ecosystem effects’ have added new burdens to research institutes. We should ask therefore, if we can measure the ability of a fisheries managers to keep effort in check, without necessarily carrying out an independent stock assessment?

  13. Is a broader approach to judging the health of a fishery available? • The WTO, or other interested bodies, cannot expect to duplicate the fish stock assessments by national research laboratories. They will have to develop approaches to monitoring (e.g. questionnaires) which do not need to specify the exact state of the fishery. • These should aim at estimating the level of risk current management approaches are incurring. The evaluation should use readily available data, and judge it against an acceptable standard (e.g. the FAO Code of Conduct for Responsible Fisheries). • The key task is to ensure that national institutions are living up to their responsibility for safe management of marine resources, and not using subsidies to ‘hide’ managerial deficiencies!

  14. Taking a higher level perspective based on the Code of Conduct, a questionnaire approach might be considered. Results can be displayed using the ‘traffic light’ approach to evaluate management performance.

  15. Can questionnaires provide reliable indicators of fishery status? It will likely be impossible for WTO to obtain formal assessments for many fisheries. If so, indicators of precautionary behaviour have to be largely based on the management measures that apply, and to a lesser extent, on their effectiveness in terms of fishery outputs. Questionnaires, such as those based on FAO’s Code of Conduct, provide one approach to judging compliance with responsible procedures (Caddy, FISHCODE, FAO, in press). A tentative example of such a questionnaire is given in the following slides, that should be completed by independent authority(ies) – see e.g. MSC for possible procedures?

  16. Such a questionnaire approach will of course require further elaboration, but:- The score on such a questionnaire could be the basis for corrective action by fisheries managers.- Achieving a minimum scoring (level to be specified) could be one criterion for judging the risks to the resource and livelihoods of those already in the fishery of introducing a subsidy to construct further capacity.

  17. Thank You

  18. Successful fisheries keep costs below revenues, but this possibility rapidly evaporates as effort rises and catch rates and biomass decline. Locating the optimal effort level is information-intensive! Adding subsidies reduces costs (fleet B), but drives the point when costs = earnings to still lower stock sizes (from point A to point B).

  19. Using subsidies to add capacity/effort is rarely necessary given a flourishing international market for fish products. However, if there is a cap on capacity, a subsidy could be considered: • Following natural disasters affecting inshore fleets (e.g. tsunamis); • For the same harvest, to convert large capacity units (e.g. large-scale foreign fishing in the zone) to small-scale domestic units, so as to enhance employment or provide local food resources,; • To move to safer harvest methods, or increase ‘add-on’ local value by improving methods; • To retrain fishers to enter other sectors of the economy; • To encourage fishers/fleet to move to less heavily fished resources; • To finance fleet buy-backs to eliminate over-capacity; • To compensate for loss of local fishing rights in setting up a MPA; • To restore coastal habitats of importance to fisheries damaged by natural disasters or anthropogenic impacts; • To set up mechanisms of international cooperation on shared resources

  20. Is there a distinction between subsidies for construction and subsidies for supplementing running costs? • Legitimate national aspirations may lead to construction of a fleet to harvest resources in its zone, even if these resources are shared, straddling, or highly migratory stocks fished elsewhere in the species range. • There is a significant risk of course, that combined with existing (foreign?) effort, the new capacity will lead to stock declines and economic hardship for the owners of the new fleet. • If this leads to the call for subsidies to reduce running costs, concern should be raised by other users that such subsidies are affecting fair competition with others sharing the same resource. • If this perspective is commonly shared, there seems a motive for distinguishing between subsidies for construction, and those used to run fleet operations. While the first may be seen as legitimate, the second may not. • Incidentally, subsidies to aidfleet replacement raise another question – if operations to date did not allow returns adequateto replace vessels, could these subsidies be seens as aiding running costs rather than just construction?

  21. To what extent do answers to the above questions differ for ‘small-scale artisanal fisheries’? Perhaps the key factors that have made the small scale sector a potential means of overexploiting, and even depleted stocks, are at least fourfold: 1) Improved technologies (fish finders, engines, monofilament gear) or inappropriate gear (gill nets, and in some cases fish traps that take important herbivorous fish that keep coral reefs free of algae); 2) A changeover from local marketing with inadequate fish storage methods (i.e. surpluses to day-to-day needs were unmarketable), to systems using ice and onshore freezers for marketing ‘offshore’; 3) The use of the small-scale sector, deliberately or by default, as an employment of last resort. This makes putting a cap on small scale capacity socially impractical; 4) The inability of many countries, for budgetary and manpower reasons, to monitor activities of the small scale sector or assess their fisheries. A subsidy programme is defensible where small scale fleets have been destroyed by natural disasters, but should not be an occasion for increasing fleet fishing power. AXIOM: A ‘boom and bust’ subsidy programme where excess fleet development is followed by an emergency programme to counter the effects of overexploitation on local livelihoods, is not a rational strategy!

  22. Can we rely on regional fishery management organizations (RFMOs) to provide reliable data on stock status? Some reasons why the work of RFMOs is frequently hampered are given in FAO 2001), namely: 1) Conservation measures may be undermined by fishing of non-parties, illegal fishing and reflagged vessels; 2) Failure of members to provide adequate information on their fisheries; 3) Political pressures related to sovereignty and national interests; 4) Poor MCS capability; 5) Poor links between science and implementation; 6) Lack of financial support;

  23. How precautionary should criteria be? - Very! (but using ‘precaution’ is not a substitute for data gathering!) Precautionary criteria are needed given inadequate data and our poor understanding of marine ecology, and our limited ability to measure the impacts of fishing. Ecosystem management’ is supposed to be precautionary, and some governments are now starting to apply ‘ecosystem principles’ in fisheries management. - however, our practical experience in ecosystem management in the sea is very limited. The only precautionary measure we can be fairly sure will be effective for conservation is one that limits or reduces fishing effort!

  24. Monitoring fisheries nowadays looks at a broader range of indicators, including ecosystem factors, environment, and economic performance. ADD Fig 5. from Caddy (1999) showing key factors (inside the rectangle) affecting fisheries production, and some important ‘extrinsics’ outside, that could be monitored by indicators.

  25. Conventional assessment-based management is expensive! • Conventional single-species assessments off developed countries are often based on surveys, or commercial catches may be sampled for more detailed data, or secondary indicator deduced from analysis, such as: • - Population biomass, and biomass/numbers of spawners (mature fish). • - Age or size structure of the population and mean sizes. • - Age or size at maturity. • - Indices of recruitment or year class strength. • - Condition factor and growth rate. • - Egg or larval surveys. • - Length-weight relationship or information on the condition factor. • - Abundance of main prey items • The reproductive potential of the adult population or its population fecundity. • Substantial expenditures are involved in this process!

  26. Can the potential effectiveness of management be estimated from budgetary expenditures? In general, qualitative or semi-quantitative indicators using the questionnaire approach may be feasible (e.g. Caddy 1999b; 2000). This should could measure inputs to the management process, such as costs of facilities (capital value and annual upkeep), personnel (numbers and salaries), and expenditures on necessary activities. The total cost of management in toto, should be a small proportion of the landed value of the product, but can rent be extracted from the fishery to pay for this? Monitoring the outputs from the management process (e.g., indicators of the successful application of inputs in terms of healthy populations), is perhaps even more important than inputs since it measures the rate of success, but requires a more intensive sampling approach.

  27. Does adding an ecosystem dimension help? The recent scrambling to add an ecosystem dimension to the techniques of assessment currently used has not yet provided a simple practical and cost-effective replacement for ‘single species assessment’. Given that doubts on some conventional assessment procedures are becoming common in the scientific literature, we should not be embarrassed to use qualitative approaches, or (in moderation) employ the precautionary approach (e.g., FAO 1995b; Anon 1997). We should consider empirical methods of judging the risk to a resource due to the management approach currently applied, as a possible basis for judging the applicability of subsidies. Above all, we could use more diverse, indicators than in classical assessment approaches and aim for the simpler objective of warning of ecological unsustainability or risk of collapse, as opposed to attempting to assess the current demography of the fished population.

  28. Data on capacity What is urgently needed in addition to catch data is a regularly updated national fleet registry, with details on licenses to fish, vessel characteristics and fishing gear in operation AND evidence that fishing license replacement is on the basis that the new vessel is no more powerful (and perhaps less so) than the one it replaces! If the resource is approaching full exploitation and fleet subsidies exist, this control mechanism on Capacity emerges as more important than ever!

  29. Readily available empirical information may not be useful for stock assessment, but may provide an indication of changing levels of risk to the population. The recent development of empirical approaches for following fisheries developments seems to arise from the following perceptions: A shortage of comprehensive data prevents full stock assessment procedures being applied to many species, and this shortage is likely to persist into the foreseeable future. 2) A wider range of qualitative indicators may be available, that while these might not directly measure biomass or mortality rates, might help signal changes in the risk to resources and environments. 3) The general acceptance of a ‘limit reference approach’ encourages judgements as to the point in any indicator series when an unacceptable risk of stock collapse exists. 4)Simultaneously displaying a large number of indicators in a ‘traffic light approach’ (Caddy 1999; Halliday et al. 2001), or a PS(I)R approach (Malkina-Pykh, 2000), facilitates visual identification of ecosystem change in a way that should precede specific investigation or modelling.

  30. What information is needed to judge the appropriate level of capacity of a fleet? There are several definitions of capacity in current use: where biological impacts are concerned, the capacity measure should reflect the number of standard days fished, or the death rate of stock due to fishing (F), so that a management measure can be linked to a fish stock assessment or the state of a resource. A measure of fishing capacity (such as fleet tonnage or engine horsepower, days fished, or investment in fleets and plant), measures an ‘input’ to the fishery, and will have to be related to some ‘outputs’ from the fishery in order to determine its biological impact.

  31. What might be considered ‘minimally acceptable levels of information?’ • For proper assessments, there is a need to monitor inputs to the fishery (effort, capacity, fuel, technology = fishing power, investments) and a range of outputs from the fishery (including: catches, catch rates, remaining biomass, species composition, spawning potential, annual recruitment, bycatch and discards, mortality exerted by fishing). • Adequate monitoring of BOTH inputs and outputs in a balanced fashion seems a prerequisite for a managed fishery, and is provided for in the Code of Conduct. Questionnaires based on the Code are now available (Caddy, in press). • To monitor risk, simpler but broader indicators may be used, such as a decline in mean size, the proportion of mature fish; biodiversity; a rise in market prices, or increasing impacts of fishing on associated species such as marine mammals.

  32. The high costs of monitoring and assessment Shortage of funding for data collectors in ports or at landing places, and for analysis of fisheries samples thus present problems. Adequate numbers of trained personnel in methods of population analysis, and budgets/equipment to allow them to work, are rarely available in developing countries. This makes annually-repeated stock assessments infrequent in most developing countries. However, some means of directly measuring the impact of different levels of fleet capacity is a priority before MSY conditions are approached.

  33. A possible procedure which places the burden of doubt on the exploiting parties Although the reality of the situation is that formal annual stock assessments are still performed for a minority of resources, my opinion is that establishing which stocks are seriously depleted or 'at risk' could be done fairly simply in a 2-3 stage process, in which the burden of proof is required from the parties fishing, and would not have to be provided at the expense of WTO or its associated organizations; as suggested by the following. A first listing of stocks that may be 'at risk' could even be done by WWF using the procedures described for analysing data reported to FAO The second stage would be to post a list of these internationally, and ask for further information from parties exploiting these resources; not just on their status, but also a list of vessels by size/fishing power categories which are exploiting these stocks. The third stage would be to find funding to send experts to make an evaluation. Since this process is precautionary however, after posting a list of stocks and coastal states/DWFNs exploiting them, and not receiving a reply from the relevant authorities, this would be reason enough to consider that there is a problem, even if other evidence is unavailable. i.e., for a WTO panel to establish that a fishery is at risk begins with a relatively simple process, which gets more complex and costly if further more refined assessments are needed. The next step however should be at the expense of the country(ies) exploiting the stock - if they do not respond adequately to a first appeal based on broad but imprecise evidence such as a drastic drop in catches and evidence of excessive demand, rising prices and excessive effort, then the stock is indeed at risk. At that point, a rough analysis based on some aspect of species vulnerability (such as biological characteristics stored in FISHBASE and the basic species biology which is usually known), may establish whether the life history is especially vulnerable.

  34. The aspect emphasized in the text then, is that both input and output data should be available. For developing countries to satisfy a ‘science-based’ assessment will be difficult, but clearly a questionnaire could establish what they are doing to ensure that: Infrastructure for data gathering and assessment exists; Management, control and surveillance infrastructure and a system of fisheries regulations is in place which bears in mind scientific principles; They collect data on effort/capacity operating on the stock and control the fleet capacity by licensing and vessel replacement criteria; They collect some biological and catch data; Ideally, some closed areas protect critical habitats for demersal species; They attempt some sort of stock assessments – if so for which species; which methods? They discuss joint management with other parties sharing resources? If they certify foreign fleets in their zone (or foreign fleets fish the same stock outside of their zone), have they considered the impact of their catches on their domestic fisheries/food security? If they are able to answer most of these questions positively, (even if they do not assess the resource, but do collect data allowing an outside expert to do this for them), the WTO should be satisfied.

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