Ownership and regulation of fishing
Open-water stocking and ranching have come a long way from the days when they were considered a mere waste of effort and money. Greater knowledge of the behaviour and environmental requirements of the species has contributed considerably to the development of suitable methods. Of special importance have been improvements in techniques of artificial propagation and rearing of fry and fingerlings, accompanied by control of predators and environmental improvements where possible.
In many cases, economic evaluations have been made and these have shown the favourable cost-benefit ratios of the operations. It is, however, obvious that indirect methods have to be adopted to estimate survivals of released stocks, when the fisheries are based on combined stocks of released and resident individuals. Data obtained by experimental marking may not always be accepted as representative of what happens in a commercial fishery. Because of all this, some scepticism is still expressed about the value of certain types of stocking, as, for example, the sea stocking of shrimps in Japan or the continued stocking of reservoirs in some of the South American countries.
Although the subject may be controversial, one of the more important constraints to theexpansion of stocking and ranching is the problem of regulating the fishing of released stocks. The majority of successful stockings described have been undertaken by, or under the auspices of, the State. Exceptions are some of the smaller operations under-taken by sport fishery associations or agencies for the benefit of anglers. Under administrative systems where the State can undertake such work on a continuing basis for the benefit of fisheries, there may not be much difficulty in justifying such programmes. The system may also permit strict adherence to regulations of fishing periods and fishing quota. But in a large majority of cases it is extremely difficult and costly to implement such regulations for cultured stocks in common property waters. It may be possible to allocate ownership rights to the releasing agency for returning spawners to a home stream in the case of anadromous species. But if fishing in the seas cannot be regulated and harmonized with the release operations, the profitability and success of the programme can be adversely affected. It is, therefore, necessary to consider in advance the economic and organizational management of the resulting fishery, before undertaking large-scale stocking or ranching.
The emergence of cage and pen culture has introduced another option for the use of open waters, at least in protected areas. It may well be possible to produce in such areas at least as many fish by such intensive culture methods as could be expected by open-water stocking. No comparative cost/benefit ratios have been worked out, but it is not unlikely that intensive culture would prove to be economically more attractive. Not all species presently used for stocking and ranching may be suitable for such intensive culture, as for example the large sturgeons or species meant for sport fishing, but at least for the species which can be cultured in cages or pens for human consumption, that option has to be considered against release into open waters.