When a stock of fish moves between the EEZ of more than one country it is clearly desirable that these countries cooperate in the research, management and rational exploitation of that resource. At the same time, there can be problems in achieving that cooperation; it can introduce another layer of administrative machinery into an overloaded system; meetings and travel between countries is expensive, and in particular some countries may be unwilling, in the period after the introduction of EEZs, to take action which might appear as sharing authority over the fisheries in their EEZ.
Cooperation is therefore discussed here in two parts: first in respect of the scientific study of the stocks, and the second in respect of the actual application of management measures. Only the second raises problems of authority. Countries are free to take whatever action they think appropriate in the light of their national objectives, and the scientific evidence. The better the science, the more likely it will be that the action taken will achieve the desired objectives.
The main benefit from international cooperation in research is that it becomes possible to consider all the information concerning a stock of fish, wherever it occurs. In the absence of such information it is very easy for a country to misinterpret what is happening to the stocks in its EEZ, even when it has good information on everything that is happening in that zone. For example, a small increase in national fishing effort could coincide with a large decline in catch rate due to a large increase in fishing on the same stock elsewhere. This might be interpreted as too heavy fishing of a small stock, and lead to the introduction of severe control measures, if the events in the other areas were not taken into account. This is perhaps an extreme example, and in practice scientists in one country should be aware of such gross changes in an adjoining country without the need for formal cooperation. However, there are many more subtle biological events, e.g., changes in migration pattern, which can affect national assessments, but which can easily be over-looked - or if known, cannot be taken fully into account - unless there is close cooperation between all countries in which a stock occurs, or in whose zones events occur that can affect that stock.
Ensuring that cooperation does cover all the countries involved is not necessarily straightforward. As noted in the previous section, the concept of “stock” is not a precise one, and it can be far from clear which countries should be included in considering a group of fish in a particular area -if Papua New Guinea is interested in knowing about the stock of skipjack around its coasts it will need information from the Solomons, but it is not clear whether it will need to have information from the Philippines or from Hawaii. Consideration of the interactions between species make the definition of boundaries and the determination of which countries need to collaborate even more difficult. For example, in some years bluefin tuna have been significant predators on North Sea fish such as herring and a complete understanding of the factors affecting the North Sea herring stocks should include information on the exploitation of the bluefin tuna when they are outside the North Sea, i.e., in the Bay of Biscay or Mediterranean. In practice such a wide scope would lead to an impossible mass of detail and a narrower viewpoint has to be taken. The area covered by any particular cooperative study, and the subjects considered within that area (e.g., one particular species, all species taken by a particular type of gear, or all species that might interact with some target species of primary interest) will therefore have to be chosen in the light of the particular problems being tackled.
This then raises the question of the nature of the scientific advice, and the types of scientific study that have to be carried out if those taking decisions on the management and exploitation of the resources are to be properly advised. This has been reviewed several times (e.g., ICES, 1977; ACMRR, 1974, 1980), and need not be discussed again here. What needs to be stressed is that advice is not simply a matter of calculating a quantity (Total Allowable Catch) that should be taken. Account has to be taken on the one hand of the existence of varied social and economic objectives, and on the other of the complexities of the natural ecosystem.
Social and economic realities need not mean - indeed should not mean - that biologists have to attempt to include economic and other factors in their analyses. It does mean that their advice must be given in sufficient detail that economists or others can determine the economic or other consequences of different actions. In these determinations, matters such as the cost of fishing (as influenced by catch rates, and the abundance of the stock) and the seasonal and spatial distribution of the catches can be as significant as the magnitude of the total catch. The results of the scientific analyses have therefore to be presented in sufficient detail that these characteristics of the fishery, and the effects on them of different management actions are available directly, or can be deduced by economic or social analyses. These last would normally be carried out nationally rather than as part of an international cooperative biological study.
Relevant biological complexities that need to be taken into account in the scientific advice include interactions between species, and natural variations. The fact that the interactions between species greatly widen the geographic area (and hence the number of countries) that might have to be taken into account has already been mentioned. At the present state of scientific knowledge and ability to control fishing some of these extensions are only of theoretical interest. For example, it would be difficult to produce an estimate of the impact on North Sea herring stocks resulting from different patterns of fishing on bluefin tuna and unrealistic to expect that management measures for tuna in the Mediterranean would be modified in order to accelerate the rebuilding of the depleted North Sea herring stocks.
With more restricted areas the interactions are more significant and more likely to be taken into account. Although the existence of interactions between species is well-known, and the need to take account of interactions often acknowledged (FAO, 1978; May et al., 1979), very little is known about the quantitative nature of the interactions between species, and the likely magnitude of some of the important factors (e.g., the amount of food consumed by an individual fish). To build models of how multi-species systems will behave under different patterns of exploitation is heavily dependent upon knowledge about specific sets of food web and energetic processes. In some cases these seem to be approaching sufficiently close to reality to be useful in determining the direction of the effects of management actions, e.g., increased fishing on anchovy will cause some reduction in the growth of predatory fishes. The models and the information used in them however are not yet sufficiently accurate to give reliable quantitative answers, e.g., by how much will the growth of predatory fish (and the catches of these fish) be decreased by a given increase in fishing on anchovy.
The impact of natural variations, e.g., in ocean currents, on fisheries can be of several different kinds. Many fish stocks exhibit great fluctuations in abundance either from year to year or over longer periods. Of particular interest in the present context are changes in distribution. These changes can alter the proportion of a stock that occurs in the EEZ of a particular country, or the degree to which the fisheries in one country are affected by events in other EEZs. For example, the sardine stock off northwest Africa has been extending the limits of its distribution southward so that a stock that was once almost solely of interest to Morocco is now shared to a large extent with its neighbours. Again, the establishment of a cod stock off southern Greenland following the warming of the water in the nineteen thirties has meant that since then a significant proportion of the cod spawning off southwest Iceland have spent the early part of their lives in Greenland waters.
A further complexity in providing scientific advice, which is a direct consequence of the establishment of EEZ, is that much more is now required to be known about the distribution, migration and stock structures of the fish. The discussions in this paper make it clear that the nature of the “shared stock” problem depends on the pattern of movements, and examples are given of the various situations. What is not made clear is that for many, and indeed probably most, fish species throughout the world information on migration, distribution and stock structures is scanty or entirely lacking. Much more information on these subjects is needed to enable countries to determine how they need to collaborate in managing their resources.
All these factors - more details from which economic analyses can be made, greater account of interactions between species, and more detail on distribution and migrations - will add to the work of the scientists. This increases the importance of the other benefit from close cooperation between countries, which is that it increases the effectiveness of the scientific research, and can enable a ‘critical mass’ of expertise to be brought to bear on these difficult problems.
Cooperation in research has always been one of the main functions of the numerous regional fishery bodies, both within and outside the structure of FAO. The structure and methods of operation of these bodies need not be reviewed here, but a few points should be made.
First is the matter of timing. Governments traditionally take action only when it is clear beyond any argument that action is needed. It may be expected therefore that action to establish cooperative research programmes will often be taken only after it is clear that they cannot manage their fisheries without this. On the other hand, experience has shown that it takes time for a group of scientists to get used to working together, and to establish effective cooperative programmes, and that it takes a further period - usually of several years - before the results of these programmes can be analysed and made available to policy makers. To take an obvious example, a tagging experiment to determine migration routes involves, as one part, a minimum period to allow the tagged fish to move from one area to another, which for long-lived fish may be several years. Some of the most interesting recaptures of southern bluefin tuna tagged as juveniles off Australia are only now occurring in the Japanese long-line fishery, some fifteen years after the initial tagging. Therefore, in the cases where arrangements for cooperation in research do not already exist, urgent action is needed to establish them.
A second point concerns the structure of the arrangements, and the responsibilities of the secretariat, if any. The most extensive experience of regional collaboration has been between developed countries, notably ICES in the north-east Atlantic. In these regions the countries concerned have, in aggregate, good expertise, and the essential responsibilities of the secretariat are routine matters such as providing meeting facilities, production of reports, etc., and restricted technical work such as the compilation of statistics reported by national institutions.
The extent of the work involved in data compilation can be quite large. At the minimum it may involve no more than storing and reproducing national statistics. The scientists will soon require more, e.g., summaries of total catches, irrespective of country of capture, usually broken down by categories such as area, gear, or size or age of fish. This requires processing of data, and probably also work with national institutions to achieve the necessary standards in the data reports. Ultimately it may be that the scientific work will benefit from the establishment of an advanced data centre, with large capacities in handling and processing data. How far the central secretariat need advance in relation to particular stocks will depend on the requirements of the scientists, and also the composition of national institutions. In developing areas the immediate requirements may be relatively small, but the work may benefit from the availability to national scientists of better facilities than they have elsewhere.
Where some or all of the countries concerned are developing countries, it cannot be presumed that they will command sufficient expertise, and the secretariat may have to provide considerable professional input. At the same time when decisions about shared stocks (and especially about possible allocation of catches from these stocks) are being taken countries will be most unlikely to rely on advice in which their own national scientists did not take a part. Activities of a scientific secretariat, however well-qualified and independent can complement but not replace the work of national scientists.
In such cases the most useful function of the secretariat may be to help provide the scientific leadership that might otherwise not be forthcoming (the parallel with the possible provision of advanced data handling facilities is obvious).
Professional and technical input from the secretariat is likely to be necessary where there are scientific problems of interpretation, and where these differences are likely to have practical implications, i.e., one interpretation is favourable to the perceived national interests of one country, and another favours a different country. Fish stocks are difficult to study. The information normally available, from surveys, biological studies or records of commercial catches, gives at best indirect information on how many fish are actually present, and how many can be caught to maintain the stock in some desired condition. The draft text for the new Law of the Sea Convention calls on coastal states to take account of the “best scientific evidence available to it” in setting management measures but, because of these scientific difficulties, it cannot be expected that this evidence will necessarily point unequivocally towards a particular action as being the 'right' action to achieve some special objective. Much will depend on the interpretation of this evidence by the scientists concerned. Inevitably this must be to a greater or lesser extent subjective. Almost equally inevitably different scientists will have different interpretations, and further, these interpretations can consciously or unconsciously be biased towards the interests of the country or other groups to which the individual scientist belongs. Differences of interests between groups, and real or suspected tendencies for interpretations to be biased in one direction or another have been one obstacle to reaching 'agreed' scientific advice in respect of whales in recent years. Similar difficulties can easily be imagined for shared stocks. For example, if a stock can be harvested as juveniles in one EEZ, and as adults in another, the location at which the harvest should be taken in order to maximize the weight caught (assuming this to be the preferred objective) will depend, possibly critically, on the value of the natural mortality rate. This is always difficult to measure, and it would not be unreasonable for scientists from the first country to favour a high estimate (which would imply benefits from harvesting juveniles), and those from the second country to favour a low natural mortality (implying that it will be profitable to wait for the fish to grow).
In these circumstances, the value of neutral scientists is great. This not so much that they should attempt to provide a single “correct” estimate, but that they can help spell out where the differences of interpretation lie, and the consequences of one or other interpretations. It would then be a matter of the administration in each country, jointly or individually, to decide what action to take in the light of this evidence.
