2.1 General Considerations in the Collection and Provision of Data and Information for Fisheries Management (7.4.2; 7.4.4)
2.2 Data Requirements and Use in the Formulation of Fisheries Policy
2.3 Data Requirements and Use in the Formulation of Management Plans
2.4 Data Requirements and Use in the Determination of Management Actions and Monitoring Performance
(i) The collection of data and information is not an end in itself but is essential for informed decision-making. It is therefore important for the management authority to ensure that the data collected are analysed correctly, disseminated to where they can best be used, and used appropriately in decision-making. Information is also needed to assure the public at large that resources are managed responsibly and that the objectives are being reached.
(ii) It must be recognized that data and information are required at the three levels, policy formulation, formulation of management plans, and the determination of management actions to implement the policy and plans. These will overlap considerably and each of the three steps will be influenced by what has happened or is happening at the other two levels. Nevertheless, the three processes are distinct, occur on different time scales and require different information to different levels of detail. Where necessary, differences in methods and approaches between, e.g., artisanal and commercial fisheries and at different time scales need to be emphasised.
2.1.1 Data requirements for different management scales
2.1.2 Verification or validation of data
2.1.3 Standardization of data collection (7.4.6)
2.1.4 Timely distribution
2.1.5 Confidentiality of data (7.4.7)
2.1.6 Costs of collection and collation of data
(i) In general, as the locality and scope of decisions moves from management implementation to management planning to policy formulation, the degree of synthesis and aggregation of information required will increase. At the level of management implementation, details on the current biomass and the age structure and distribution of a stock may be extremely important. However, at the other end of the spectrum, the policy-makers may need to focus mainly on the options for potential annual yield, provided by technical experts, the fisheries' national socio-economic role and their interactions with other macro-economic or macro-policy considerations. These distinctions are discussed in more detail in 2.2 to 2.4.
(ii) The management authority should be responsible for setting-up and overseeing the structures and mechanisms for routine collection and analysis of the necessary data.
(i) Approaches to collecting data for fisheries management vary substantially, depending on, for example, the nature of the fishery, the staff and facilities available, and the social and economic importance of the fishery. Whatever methods are used, the quantity and quality of the data collected will have a direct influence on the quality of the management which can be exercised, and so the most effective use must be made of personnel and facilities available for data collection.
(ii) The verification or validation of data is essential to ensure that it is accurate, complete and gives a true indication of the state or value of the factors under consideration. The problems associated with the collection of fisheries data mean that the risks of collecting erroneous or inappropriate data are very high without careful and statistically valid design and monitoring of sampling approaches.
(iii) Different types of data will need to be verified in different ways. Some examples of methods to validate data include:
(iv) Adequate training and supervision of staff involved in monitoring are essential if the data collected are to be valid. Staff involved in data collection are frequently relatively junior in organizational hierarchies. However, they are also frequently expected to work in remote areas or as the sole observers aboard ships, often with no contact with their supervisors or colleagues for lengthy periods. It is important that they are prepared for this with adequate training and that every effort is made to maintain morale and an awareness of the role of their task within the broader fisheries agency. Regular site visits, incorporating quality control, should be made by supervisory staff to data collection points and regular in-service training sessions held.
(i) Many stocks, and possibly most marine stocks, are not found exclusively within the areas of national jurisdiction of a single State but are distributed across international boundaries. As stated in 1.3.1, stocks must be managed as units or the management actions will almost certainly fail to achieve the desired objectives. Where this requires cooperation between management authorities of different countries, provinces or local agencies, the task of cooperative management is made much easier and more effective if the different partners in the cooperative management all collect data according to common definitions, classifications and methodologies and in a pre-agreed, standardized format, enabling all data to be combined and compared as required.
(ii) Collection of data in a standardized manner will require that the cooperating partners meet periodically to agree on the data requirements, the methods to collect the data, the amount of data to be collected and to review the sample design within each independent jurisdiction. In addition, joint training of staff involved in data collection will almost certainly be advantageous.
(i) The prompt provision of data in time for appropriate decisions and action to be taken is essential for effective fisheries management. Regular and frequent, typically annual, assessments of fisheries and resources, and a review of appropriate management options in response to changes are essential, and these can only be effective if they incorporate reliable and up-to-date data and information. With due regard for confidentiality requirements (see Section 2.1.5), management authorities should participate in and encourage sharing of information and data amongst different agencies and interest groups with genuine needs for these (7.4.6; 7.4.7).
(ii) Collection of appropriate and high quality data can be complex and costly but, in view of the above, fisheries management authorities must ensure, through the provision of adequate support, that the necessary data collection and analysis systems exist and function effectively.
(iii) Particularly where distances between sampling points are great as, for example, with highly migratory or straddling stocks, the potential role of data transmission by radio, fax, Email and satellites or transponders installed on commercial fishing vessels should be considered.
(i) It is usually important to the fishing industry and to individual fishers to know that aspects of the information which they supply to fisheries management authorities are kept confidential, in particular that information or those data which could be used by their commercial competitors to gain an advantage. In view of this, fisheries management authorities must implement policies and strategies which ensure confidentiality of data falling into this category. While aggregated catch data are generally not regarded as being confidential, data relating to the fishing activity of individual vessels or company specific catch rates, fishing localities and fishing strategies are frequently seen as being of potential interest to competitors and therefore need to be kept confidential.
(ii) Fisheries management authorities need to liaise with all providers of data to establish which data should be kept confidential. Failure to do this could result in future problems in obtaining data from companies, falsification of data or similar problems related to or stemming from a lack of trust in the management authority.
(iii) Related to commercial confidentiality, it is usually desirable to ensure that the data collection tasks and structures of a management authority are kept totally separate from the enforcement tasks and structures. Failure to do this will generate a fear amongst fishers that the data they supply to the management authority to facilitate monitoring and assessment of the stocks and fishery will be used against them by the enforcement arm. Again, this could lead to difficulties obtaining data or to falsified or incomplete data.
(i) The collection, collation and dissemination of data should be carried out in the most cost-effective manner possible so as to minimize costs while acquiring the required information. Collection and analysis systems should be based on appropriate statistical designs to ensure that sufficient but only necessary data are collected.
(ii) Duplication in data collection and analysis should be avoided unless deliberately intended for validation purposes or for other reasons related to maintaining quality. Unnecessary duplication is most likely to occur where there are straddling or shared stocks with multiple authorities having common responsibilities.
2.2.1 Types of fisheries, the stocks they depend on and their ecological and environmental context
2.2.2 Fisheries characteristics
2.2.3 Social and economic information
2.2.4 Monitoring, control and surveillance (7.7.3)
(i) The role of fisheries in the regional, national or local economy must be understood before the best policy decisions can be made. Therefore, there must be a clear understanding of the position and status of fishing in the national economic and social interest.
(ii) Fisheries usually generate benefits in terms of economic return, employment and food production and in terms of recreational opportunities. However, they also generate costs to the community or State which may arise through meeting management requirements, provision of facilities or subsidies, interference with or prevention of other activities in the same area and other causes. Proper policy decisions require up-to-date and accurate information on these factors.
(iii) A summary of the types of data required in the formulation of policy is provided in Table 1.
(i) The structure of fisheries, both within areas of national jurisdiction and beyond, may be complex, targeting on a range of species with different gears, involving different scales of operation and different fishing zones and landing sites. Fisheries may range from a commercial focus to subsistence to recreational. At the level of policy-making, information on the potential magnitude, possibly measured in terms of potential catch, economic value and employment opportunities for each fishery or each stock should be provided. Failure to do this could result in policies which lead to unrealistic social or economic expectations and hence encourage over-exploitation.
(ii) There is frequently interaction between fisheries for different resources in an area, and, as mentioned in 1.3.1, fishery activities on one stock or biological community may impact others. Therefore, fisheries management authorities need to advise policy-makers on the potential implications for other fisheries of any changes in policy for a given fishery (7.2.3).
(iii) Fish stocks depend on their environment, and the nature of this dependence may differ for different life-stages. National policy decisions which have implications for the environment of stocks important to fisheries, even if the decisions do not directly involve fisheries, need to be made taking cognizance of their implications for affected fisheries (7.2.3; 7.3.5; Fishing operations. FAO Technical Guidelines for Responsible Fisheries. No. 1. Rome, FAO. 1996. 26p.).
(iv) Lessons can frequently be learnt from the successes and failures of the past, and fisheries management authorities should provide policy-makers with concise histories of the fisheries under consideration, with particular emphasis on problems experienced, previous management strategies followed and their consequences.
(v) The importance of integrated coastal area management (ICAM) and specifically the integration of fisheries into coastal area management is now widely recognized (Article 10 of the Code of Conduct for Responsible Fisheries; Integration of fisheries into coastal area management. FAO Technical Guidelines for Responsible Fisheries. No.3. Rome, FAO. 1996. 17p.). These principles have been developed with an awareness that many coastal areas are subject to open access and frequently to multiple use. The fact that many coastal areas are suffering from increased population pressure exacerbates the problem. Similar problems of multiple use occur in inland waters, necessitating a similar concept of integrated basin management. Fisheries management authorities should be playing an active, and proactive, role in encouraging policy makers to develop integrated policies and plans for the terrestrial and aquatic environments.
(i) Policy decisions on regional, national or local fisheries should be formulated and made in the full knowledge of the nature of the fisheries under consideration, including the different fishing groups or fleets and their composition, as well as the fishing grounds they use or propose to use.
(ii) Fisheries policy should recognize the potential biological, technical, social and economic interactions between fleets within a specific fishery and between fisheries. Policy should endeavour to minimize negative interactions which could lead to conflict or to poor performance by one or more fishery.
(iii) Policy should take cognizance of the impact of fishing operations on the environment and hence encourage practices which are sustainable and do not result in avoidable damage (7.2.2f) and g); 7.6.9, and Fishing operations. FAO Technical Guidelines for Responsible Fisheries. No.1. Rome, FAO. 1996. 26p.)
(i) Humans are an integral part of fisheries systems and fisheries systems cannot be understood unless the social and cultural features and the economic characteristics of the people and communities within the system are understood. Any fisheries management decision is likely to have an impact on peoples' livelihoods and way of life and the purpose of collecting and analyzing social and economic information is to be able to anticipate the nature and extent of these impacts and to make decisions so as to optimize them. Collection and analysis of data on relevant social, economic and institutional factors is therefore essential for responsible fisheries management (7.4.5).
(ii) At the level of policy, the decision-makers should have information on the following:, the interest groups, their features and their interests in the fishery;
(iii) The economic role and performance of fisheries is influenced by the whole regional, national or local economy, and information on these influences is required for wise and responsible policy development. Hence information is required on the main factors contributing to the broader economy, the main factors driving or hindering development within this broader economy and the influences or potential influences of any development on the fisheries sector.
(iv) Social, economic and even institutional characteristics are as dynamic as biological features and tend to change with time. It is therefore important to monitor and provide information on trends in these factors, including on issues such as demographic changes, movements of people, trends in the markets and issues related to costs in order to assist in the development of policies which will not rapidly become obsolete.
(v) Fisheries are frequently marked by conflicts between different sectors or within sectors, and an important role of policy is frequently to determine a fisheries environment in which conflict or the potential for conflict is minimized. Information is therefore required on historical and existing conflicts and their causes, as well as on possible solutions to such conflicts.
(i) The successful implementation of policy is dependent, inter alia, on the effectiveness of monitoring, control and surveillance. Aspects related to this are discussed particularly in Section 4.3.3 and Fishing operations. FAO Technical Guidelines for Responsible Fisheries. No.1. Rome, FAO. 1996. 26p. These provide comprehensive information on the requirements for monitoring, control and surveillance of fishing operations, with particular emphasis on larger vessels.
(ii) In setting fisheries policy, the previous records of success and failure in monitoring, control and surveillance in the fisheries of the region, State or local area are important in evaluating the likelihood of success of the approaches proposed in any new policy.
(iii) The costs of monitoring, control and surveillance to a fisheries management authority can be substantial and need to be considered in setting policy. In some cases, the value of the fishery to the users or society may not be sufficient to justify the costs of a proposed monitoring, control and surveillance system and cheaper alternatives may need to be developed. Only approaches which are feasible with the personnel and facilities available to an agency should be considered. Implementing a management plan which cannot be enforced will damage the credibility of an authority, with repercussions possibly spreading to other fisheries.
(iv) Generally fishers and other interest groups will only support legislation and regulations which they consider legitimate. In setting policy, it is important to consult with all recognized interest groups, and to secure their cooperation and participation, to ensure such legitimacy. In addition, the management system should attempt, where possible, to provide appropriate incentives for compliance as well as penalties for non-compliance.
2.3.1 The target stock, or stocks, and its environment
2.3.2 Fishery characteristics
2.3.3 Social and economic information
2.3.4 Monitoring, control and surveillance
(i) The formulation of a fisheries management plan is discussed in detail in Section 4.1. A fisheries management plan is an explicit arrangement between a fishery management authority and the recognized interested parties. It should identify these parties and clarify their respective roles, rights and responsibilities. It should list the objectives agreed on for the fishery and the harvesting strategy, rules and regulations applied to realize those objectives. It should also describe the mechanisms for on-going consultations, the arrangements to ensure compliance and any other information relevant to the management of the fishery.
(ii) The formulation of a management plan should include iterative consultation between the management authority or authorities and the user groups. Stock assessment and modelling approaches, where feasible and appropriate, should be used to investigate the biological, social and economic implications of different harvesting strategies and management options, and the results used to assist in the selection of the most appropriate plan. A summary of data and information essential or desirable in the formulation of management plans is provided in Table 2.
(I) The potential yield from a stock or community is dependent not only on the biological characteristics of the stock and on the environment, but also on the harvesting strategy used, in particular the age structure and species and sex composition of catches, and the timing of fishing in relation to maturity and spawning. These characteristics of the catch can also affect the social and economic benefits derived from the fishery. For example, smaller animals may command a higher price per unit mass than larger animals in some markets while in others, the opposite situation may apply.
(ii) In the formulation of management plans, the management authority, with the participation of the interest groups, should investigate and provide information on the biological, social and economic implications of different harvesting strategies and management options. For biological assessments, data will be required on historical catch and effort in the fishery, the size composition of the catch (translated into age composition, if possible) and the sex and sexual maturity characteristics of the catches.
(iii) While it is sometimes possible to undertake reliable stock assessments using fisheries information alone, independent estimates, or indices, of stock biomass with time generally provide very useful supplementary data on stocks. Where the value of the fisheries being managed justifies it, management authorities should attempt to collect, annually or biennially, fishery-independent estimates of stock biomass or abundance.
(iv) Stocks and ecological communities are influenced by other stocks and ecological communities with which they interact, and changes in their population structure induced by fishing can, in turn, influence these interacting stocks or communities. Where possible, information should be collected, even if only qualitative, on the nature and strength of such relationships to allow the implications of different management plans on non-target species or communities to be evaluated. Basic data for this would normally include information on trophic interactions through studies on diets of interacting species and on the relative abundances of interacting species.
(v) Information on environments critical in the life history of the stocks or communities should be considered in the development of management plans, particularly for inland waters’ species or for marine species where one or more life stage occurs inshore. This will enable consideration, and inclusion, of the possible impacts of other uses of these environments or habitats in the management plan.
(i) Generally, management plans are developed on fisheries which already exist and may have existed for many decades. The fishery on any given stock may be simple, consisting of a single, relatively homogenous fleet, or may be complex, consisting of several different fleet types ranging from, for example, sophisticated factory ships to fleets of artisanal vessels, each fleet using distinct gear with distinct selectivity patterns or fishing different fishing grounds. A management plan needs to consider each of these fleets in terms of their impact on the resources and, in turn, the impact of a management plan on them.
(ii) This requires that data and information be collected and analysed on each fleet such as: the number of vessels or units; their gear characteristics and the selectivity of the gear; any seasonality in fishing; the locality of fishing in relation to the distribution of the stock and other fleets; any navigational or technological aids which assist in fishing; and related factors.
(iii) Systems for sampling landings need to be designed to ensure that the weight of landings and the biological characteristics of the catch, as well as effort, are accurately determined for each fleet. Where there is reason to suspect that discarding of unwanted portions of the catch occurs before landings are recorded, the quantity, species composition and biological characteristics of the discarded portion should be estimated. Observers during fishing operations, or simulated commercial fishing with chartered commercial vessels, are generally the most reliable means of obtaining these estimates.
This section should be read in conjunction with the information provided in Section 2.2.3, as there is considerable overlap in the data requirements at the level of policy and of the formulation of the management plan. The details provided in these sections should not be taken to be encouraging major involvement of the management authority in the commercial operations of the various interest groups. In most cases, these interest groups will be in possession of the best information on the economic details and trends necessary for successful operation of their fishery interests. Under such circumstances, the role of the fishery management authority will be more to provide advice where necessary and to consider, or facilitate consideration of, issues of common interest between different fisheries interest groups, and between fisheries interest groups and others whose activities interact with the fisheries. This may frequently require capabilities in multi-criteria decision-making and conflict resolution (see Sections 4.1 and 4.2).
(i) Fisheries may also be aggregated into production units, which may not coincide with the interest groups. For example, a production unit may consist of a boat with its associated crew, a single net such as a seine net and those required to operate it or a factory and its management and labour. The impacts of management decisions must be considered in terms of production units as well as in terms of the interest groups. It is therefore essential to identify the types and number of production units in a fishery and to consider the impacts of production units on the fishery and the impacts of management decisions on production units in formulating a management plan. Fishing effort is normally a function of production units and management actions may involve direct action on these units, either altering the number or influencing their mode of operation.
(ii) Interest groups will generally be heterogeneous in structure, and management action may have a different impact on one sub-group within an interest group than on another. For example, the role of women in an artisanal fishery will frequently be different from that of the men. Children may also have a distinct function. Decision-makers, particularly at community level, may be dominated by older men. Information on these differences needs to be collected and analysed to enable evaluation of the impacts of a management plan on all the distinct sub-groups within an interest group. Failure to do this may result in the failure of a management plan because of unexpected social or economic consequences.
(iii) The information necessary to forecast the economic impact of fisheries management actions needs to be collected and analysed for use in the formulation of a management plan. Any action is likely to have different economic implications for the different interest groups, sub-groups and on the fishery as a whole, and these implications need to be estimated and considered. The economic importance of fisheries involves not only people and transactions related to the capture and processing of the fish but also, more generally, the dynamics of investments and markets, and this broader importance must also be considered. For example, in remote coastal areas whole towns or villages may be ultimately dependent on fisheries and hence affected by fisheries management decisions and plans.
(iv) Economic factors which need to be taken into account for each interest group, and their sub-groups, include:
(v) The contribution of the fishery to employment should be quantified. Fisheries management decisions frequently have an impact on formal or informal employment, and the impact of a specific decision, or plan, on this should be considered. Labour in fisheries is frequently seasonal in nature and this should also be explicitly considered. For example, management decisions that ignore the seasonality of fish or labour availability are likely to fail.
(vi) It is important in the formulation of a management plan to have information on the existing institutional structures pertinent to that fishery (7.4.5). This requires that information is available on:
Again, this information should be used to assist in ensuring that the opinions and interests of all groups and sub-groups are genuinely considered in the management plan and that the probable impacts on and responses of these groups and sub-groups have been considered and appropriately covered within the plan. Failure to do this will increase the risks of failure of the management plan to achieve its objectives, or result in inappropriate objectives being selected.
(vii) Where there are appropriate institutions in existence, such as traditional structures, these should be used as a part of the fisheries management system. For example, if a community has an accepted and functional system for determining access to a fishery or regulating fishing seasons, this should be incorporated into the fisheries management plan to facilitate both acceptability and implementation. However, care needs to be taken that the institution is appropriate for the function or functions being delegated to it. Institutions which have a customary role may not be appropriate for other non-customary functions and their decisions and actions may not be accepted by the community if they are beyond the normal jurisdiction of the institution. Information is therefore required on the customary roles of existing institutions and on roles which can successfully be transferred to them.
(viii) Finally, social, economic and institutional factors are dynamic and are subject to change. Cultural and political factors may also lead to changes in access distribution or changes in pressures for access. Changes in the market, whether local or international, may result in substantial shifts in fishing behaviour or strategies. All of these may mean that the objectives initially identified for a management plan become rapidly obsolete. Therefore, trends in such important factors need to be described and the information on their implications for a management approach or plan collected and evaluated. Failure to do this may result in a management plan becoming unworkable in a short space of time.
(i) Monitoring, control and surveillance of fisheries is critical to their successful management, and the widespread failure of fisheries management on a global scale has, in large part, been a result of the inability of regional authorities, States or local authorities to enforce successfully or otherwise ensure compliance with their management regulations and to monitor accurately the behaviour and performance of the fishers. Responsible fishing requires effective monitoring, control and surveillance, which is dependent on the collection, collation and analysis of accurate and relevant data and information.
(ii) Because of the importance of monitoring and control, the implications for it of alternative management plans must be seriously considered by management authorities in selecting the most appropriate plan. Management plans should not be adopted where their implementation cannot be adequately monitored and controlled. Some examples are listed here.
The most appropriate combination of control measures will depend on the nature of the resource, the fishery and the capacity of the management authority.
2.4.1 The target stock, or stocks, and its environment
2.4.2 Fishery characteristics
2.4.3 Social and economic information
2.4.4 Monitoring, control and surveillance
(i) An integral part of a management plan should be a management procedure. A management procedure specifies how management actions should be determined and implemented, by describing which data should be collected, how they should be analysed and exactly what management action should be taken according to the results of the analyses. Management actions and the means by which they may be adjusted for changing circumstances, such as biomass fluctuations, should be determined by pre-negotiated management procedures. The specific actions can then be implemented by the management authority without the need for additional consultation and negotiation. A management procedure may also include contingency plans, also reviewed in advance with interested parties, enabling the management authority to undertake speedy and effective action in cases where the stock falls to levels requiring emergency action. If circumstances change before a review of the management plan is due, to the point where the management plan and procedure need to be revised, the requirements become those of 2.3.
(ii) Except under exceptional circumstances of either very high catch or very low biomass, valid and scientifically defensible estimates of the risk to a stock induced by a particular fishing strategy can only be obtained by looking at projections over the medium to long term, typically ten years or more. Such studies should underlie the development of management plans and their associated management procedures. It is not possible to estimate reliably the impact on a stock or community in the medium to long-term of a single ad hoc decision on allowable catch or effort. Therefore, management decisions should be made on the basis of a pre-negotiated management plan and procedure, the impact of which has been tested over a suitably long projection period.
(iii) The data required to implement a management plan, usually based on monitoring a stock or fish community and the fishery, are shown in Table 3.
(i) Invariably, an estimate or index of stock size will be required for the adjustment, typically annually, of those control measures included within a management plan. If the management procedure includes a requirement that there should be an annual or seasonal adjustment to, for example, the TAC, total effort, length of a closed season or other measure to regulate fishing mortality, this adjustment will almost certainly need to be made on the basis of the best estimate of the status of the stock. Hence the management authority must ensure that it collects, collates and analyses the data necessary to determine as precisely and accurately as possible this index or estimate, in time for the decision to be made. Probably the most commonly used index of abundance is a mean commercial CPUE figure for the period under review for the fishery or for a representative sub-section of the fleet. The precision of such an index should be commensurate with the risk involved and the possibility of an over-estimation of stock size should be covered under the precautionary approach.
(ii) The spatial distribution of living aquatic resources is dynamic, changing seasonally and sometimes markedly from year to year. Changes in distribution can cause changes in catchability by the fishery or by survey gear. These could be interpreted as changes in abundance, leading to incorrect decisions on management action being taken. Therefore, CPUE data should not be used alone without some additional information on geographic distribution and trends in stock distribution. The best approaches to this are not well defined, but a relatively simple approach that can be taken to incorporating geographic trends is to stratify the area or areas in which a stock is fished into sub-areas, and to analyse each sub-area separately. This will enable evaluation of the CPUE, or survey index, in a variety of localities and thus increase the probability of picking up changes in CPUE in parts of the range brought about by changes in distribution.
(iii) As with data for the development of a management plan, if the value of the fishery can justify it, a valid fisheries-independent estimate of stock abundance provides extremely useful supplementary information. For fisheries which are highly dependent on recruiting age-classes (such as most short-lived species), a survey directed on pre-recruits may be most useful. Surveys should use standard fishing techniques which must remain constant, or be calibrated to each other, for valid estimates of trends or changes in stock abundance to be made from one survey to the next. Experience has shown that it is frequently difficult to avoid changes in fishing technique, and care must be taken in interpreting data where this is suspected to have occurred.
(iv) The Code of Conduct calls for emergency action in the event of natural phenomena having substantial actual or potential negative impact on living aquatic resources (7.5.5). Therefore, at least rudimentary information on the status of the key environmental parameters, such as sea surface temperature, climatic conditions (such as wind strength and direction, rainfall, river outflows, etc.) should be routinely collected and analysed to assist in the detection of abnormal phenomena and their influence on the stock which may require particular management measures. Other factors which could be considered include, for example, the water level or seasonal flow patterns in inland waters, changing chlorophyll abundance and distribution, unusual seasonality, oxygen concentrations in low oxygen areas, and the status of key predators and prey on the stocks. Remote sensing has a potentially important role to play in this area.
(i) The nature of the fishery, and the fleets comprising it, here considered to be not only discrete groups of vessels but also of land-based fishers (see Definitions), should have been considered in the development of the management plan. In implementation of the management plan, as with the resources, the role of information on fishery characteristics would be limited to those types of data required by the management procedure to support control decisions.
(ii) The most common use of fishery-related data in implementation of a management procedure is in the use of effort statistics to facilitate estimates of catch-per-unit-effort (CPUE). Again, the method of collection and analysis of catch and effort data should be carefully specified in the management plan. This would normally involve obtaining estimates of the total catch per fleet comprising the fishery and of the total fishing effort, in appropriate units, exerted by each fleet. These would then be interpreted collectively to provide an index of stock abundance, taking note of the considerations discussed under 2.4.1. It may also be possible to use representative sub-sets of a specified fleet component for these calculations where data for the whole fleet are not available. Care must also be taken in this connection in deciding on vessel categories by size, gear type and fishing behaviour. In special cases, for example where one or more fleets are fishing on the same age component of the stock in the same area and with gears of equivalent selectivity, it may be possible to use the data from only one of the fleets for assessment of an abundance index.
(iii) The characteristics and behaviour of the fleet should be monitored to facilitate correct interpretation of CPUE trends. Any changes in fishing grounds, seasonal distribution of effort, gear type or other factors which could influence efficiency of the fishery need to be considered in interpretation of the catch and effort data.
(i) In general, the social and economic features of the fishery should have been considered early in the development of the management plan, and the agreed needs and preferences of the various interest groups should have been incorporated into it. Hence, implementation of the pre-negotiated management plan should be in the best interests of the different interest groups, including important sub-groups within the groups. Therefore, social and economic considerations would not normally be a major input into the management procedure used to determine annual or seasonal control measures.
(ii) Nevertheless, social and economic forces and dynamics can influence the fishery, inter alia giving rise to changes in the behaviour of the fishers (see Section 2.3.3). For example, changes in market preference for size could result in changes in the fishing strategy of the fishery and resulting in changes in CPUE which are independent of stock abundance. On-going liaison with the different interest groups, and monitoring of appropriate social and economic indicators to detect such changes, should be carried out. Where necessary such changes will need to be reflected in the calculations or implementation of the management procedure.
(iii) The management plan should include explicit statement of objectives and these will normally include social and economic objectives. The degree to which the management plan is succeeding in attaining such objectives should be monitored continually and the reasons for and implications of any marked failures in achieving objectives evaluated. Serious failures in performance of a management plan could lead to a decrease in compliance with its provisions or strong pressure to revise the plan without waiting for the scheduled routine review. However, it must be accepted that the natural variability in fish abundance and productivity means that social and economic benefits are likely to be similarly variable from year to year. Therefore, performance of a management plan must be evaluated over a number of years and not abandoned whenever returns fall below the expected average return.
(iv) Notwithstanding the existence of a pre-negotiated and agreed management plan, experience has shown that the interest groups will tend to try and depart from the management plan when it results in decisions that they perceive are not in their immediate best interests, for example if it leads to substantial declines in TAC. In such cases, social and economic arguments are normally used to support a requested departure from the management plan. The management authority should be in possession of the data and information necessary to evaluate these claims of social or economic hardship and, therefore, to be able to weigh them up objectively against negative impacts such as an increased risk to the stock. In general, for the reasons given in 2.4 above, departures from a management plan should only be considered in exceptional circumstances.
(i) Monitoring involves the collection, measurement and analysis of data and information on fishing activities and is therefore largely covered in the preceding sections. In addition to collecting the data necessary for implementation of a management plan (see Section 2.4), fisheries management authorities must ensure that they are collecting on a regular and continuous basis the data necessary for the next revision of that plan (see Section 2.3).
(ii) Control refers to specifying the terms and conditions under which resources can be harvested and surveillance involves checking and supervising fishing activities to ensure all applicable laws and regulations are being observed by the participants in the fishery.
(iii) Monitoring, control and surveillance needs and approaches will vary substantially from fishery to fishery and even fleet to fleet. For example, the approaches are likely to be very different for small-scale artisanal fisheries fishing in diverse, tropical ecosystems and large-scale industrial fisheries utilizing essentially single stocks.
(iv) Monitoring, control and surveillance require a knowledge of the details of the fishers, the gear they are using, and the port or ports of registry and landing. Such information could, for example, be obtained from a comprehensive frame survey undertaken every two to three years.
(v) Thereafter, at the simplest level, acquiring the data required for monitoring, control and surveillance may involve simply collecting catch and effort information at landing points and encouraging fishers to report any infringements in regulations they observe. However, at the other end of the spectrum, monitoring, control and surveillance may involve the use of dedicated patrol craft and aircraft supported by effective administrative and legal structures. In this case, operations of surface craft and aircraft used for this purpose should be closely coordinated, and patrols should be based on an historical understanding of fishery or fleet operations.
