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A fishing fleet in a harbour in Chile
A fishing fleet in a harbour in Chile


Shared stocks are stocks of fish that migrate across the boundaries of adjacent Exclusive Economic Zones (EEZs) of two or more coastal states. Such sharing could happen simply through random dispersion (e.g. the stocks permanently covers and area that expands over more than one EEZ), actual migration (e.g. during its life cycle, stocks may follow migration routes that cross from one EEZ to another) or both.

There are more than 500 maritime boundaries in the world between adjacent EEZs). Significant proportions of the world's fish stocks lie across these boundaries and are fished by two or more nations. The four major stocks in the Baltic - salmon, cod, herring and sprat - which are shared among the nine Baltic states, are good examples. Other well-known shared stocks are: hake (Argentina, Uruguay); North Sea herring (the Faeroe Islands, Iceland, Norway); Pacific salmon (Canada, the United States); pilchard (Angola, Namibia); and sardinella (Côte d'Ivoire, Ghana, Togo). Most shared stocks are still not managed jointly by neighbouring states, despite increasing fishing pressure on them.

Effective management

The effective management of shared stocks requires negotiations and agreement between the States concerned in order to settle some key issues such a resources access allocation, application of compatible management measures, etc. It is essential that the shared stocks be managed as unit populations. Isolated stock assessments, carried out for only part of the stock, and incompatible management measures have little value, especially where the resources are migratory or have a high rate of mix or exchange between EEZs. Thus, one priority consists in joint stock assessment and the sharing of resource data among all states within whose jurisdictions the stock is fished.

Allocation mechanisms and the negotiation of shares need to be determined directly by the parties with clear rules established through negotiation, if necessary with the help of an independent arbitrator. Parties should be willing to review and update sharing arrangements regularly, irrespective of their investments in the fisheries sector to take account of the evolution of the resource. Recognizing the trade-offs between fisheries and other sectors may be integral to a successful negotiation. A negotiated solution may be achieved more easily if it is favourable to the state placing the highest valuation on the fishery, in return for some form of compensation to its neighbours.

Development of management schemes

The development and implementation of joint management of shared stocks generally proceed stepwise. An appropriate start is cooperation in research and data-gathering, leading to cooperative management, first through technical measures, and then through agreements regarding access to and allocations of resources. This provides the basis for bargaining over management strategies and harmonized regulations.The conclusion of agreements over surveillance and control completes the process.

States may wish to negotiate an agreement specifying matters such as the standardization of data collection and cooperation in research and stock assessment. Joint training of personnel in standard management procedures, common marking of vessels, the use of standard radio call signs and the exchange of registries of vessels authorized to fish the resource should follow shortly. Such an agreement could lead to defining standard procedures to follow in the case of infringements by fishers of the other party.

Even if an initial agreement does not lead to a fully effective mechanism for management of common stocks, there are advantages in going at least part of the way towards such a goal. The information exchange can result in each party making management decisions in the light of full knowledge of the situation of the fishery exploiting the shared stock in the other country.

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