International Baltic Sea Fishery Commission | |||||||||||||||||||||||||||||||||||||||||||||||||||||||||
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AquacultureAquaculture is the raising of fish under managed conditions. The products, live fish, can be used directly for human consumption or for releases. These releases can be for, e.g. enhancement, for sea ranching or for put-and-take fisheries in ponds and lakes. The production takes place both in private and public owned enterprises. A particular production around the Baltic is the production of fish (particularly salmon and trout) for stocking. A significant proportion of the salmon stockings is legally required as compensations for blocking of rivers.IBSFC requested member states to provide comprehensive information on all aquaculture production independent of the usage, however more information is needed for the sustainable development of aquaculture. The aquaculture production in the Baltic area is from a global perspective rather low because of the infavourable natural conditions. The huge salmon farming activity in Norway has had a negative impact on prices and the market for, especially, reared salmonids. The major production in the Baltic area therefore often takes place in relatively small farming sites, in many cases combined with either a fishery or further processing, e.g. smoking of the fish. The products are mainly distributed locally more or less directly to the consumer. Interactions with the Environment Fish kept in net pens or ponds impact neighbouring areas of the pens and the recipients of the water from the ponds by excess feed and by nutrient outputs. These problems are of a local character. For the Baltic sea these outputs are of less importance compared to other harmful inputs from human activities. Some inland aquaculture activities may have significant adverse effects on their surroundings however traditional warm water fish farming connected with water retentioning could improve water quality by sedimentation and selfpirification process. HELCOM Recommendation (18/3) concerning measures aimed at the reduction of discharges from marine fish farming was adopted by the Commission in 1997. This Recommendation does not apply to natural fish cultured for re-stocking purposes. Through this Recommendation phosphorus and nitrogen discharges from marine fishfarms are expected to be reduced. Furthermore the quality of best environmental practice and best available technology in the field of aquaculture (which is below common standards compared with other food industry sections) should be improved. All possible effects and environmental changes including synergistic effects and ecological loops arising from aquaculture should be considered before permissions for new production sites are granted. In EU fish farming can be included in national plans such as water protection plans. Larger scale fish farming needs a special permit from an independent institution. Special projects to decrease nutrient discharges are being carried out. Fish farming is developing methods to meet the requirements of sustainable development. Locally reared and adopted fish stocks should be preferred as smolts, rather than those from abroad, in order to avoid, as far as possible, risks of spreading diseases especially for fish in high concentrations. Fish farming in the Baltic area is in that perspective no exception and a number of fish diseases have been reported. Furunculosis is, in coastal areas, the most serious threat. The production in the farms could be secured by the use of prophylactic measures or, in acute outbreaks, with proper medical treatment. Even if no evidence has been shown for a spreading of the diseases to fish migrating through the rearing areas (e.g. salmon and sea trout), concerns have been expressed. As already determined in the IBSFC Salmon Action Plan 1997-2010 the protection of the genetical safety of wild stocks from the influence of cultivated fish should be ensured. Aquaculture production for Human Consumption The production by country and main species in the Baltic area in 1996 is given below together with proportion of total production by country..
Other species of importance are silver carp, arctic char, eel and crayfish. Rainbow trout is by far the most farmed species in the Baltic area. In Finland, farming of rainbow trout mostly occurs in coastal areas, especially in the archipelago areas. The production of carp takes place in inland ponds. The production of eel is so far comparatively low, but experiments to improve the technology is going on. In northern Sweden some promising results with arctic char has resulted in increased interest for the species and the production is likely to increase in coming years. In Estonia, the main limiting factor in aquaculture sector are the marketing problems and as a consequence of that the lack of investments. Aquaculture does not belong to the priorities of economy. The natural conditions are also not favourable - the water supply, quality, temperature regime etc. being insufficient for intensive fish farming. The domestic market is saturated with competing cheaper aquaculture production of neighbouring countries and fish caught from natural waters. In the last years demand for aquaculture seems to be rising. One of the prospectives of development is the combination of fish farming with ranching in natural waters. There are some signs of recovery of fish farming: the owners of small ponds or lakes at the farmsteads show rised interest in fish farming trying to restore abandoned fish ponds. In Latvia the common carp is the main species in commercial farming and mainly farmed in open air ponds by an extensive method. The rainbow trout is grown in farms as complementary product in indoors facilities only. In 80s it was popular to grow the rainbow trout in cages in sea or lakes, but this method is not applied in Latvia anymore. The transition period to a market economy had a dramatically negative impact on farmed fish production, which during the last years has decreased 12 to 20 times as compared to the end of the 80-s. In Lithuania 20 private carp farms are operating about 10,000 ha of ponds. The farms have yearly produced up to 6,000 tonnes of commercial size carp in previous years. Production of carp was reduced to 1,500 - 2,000 tonnes per year in most recent years because of market problems. Two state owned hatcheries and some small private farms produce up tp 20 tonnes of rainbow trout per year. In the Russian Federation (in the North-Western zone) there are at present five state rearing plants and several plants operating on commercial basis to produce consumer fish. Aquaculture production for enhancement, stocking and put-and-take fisheries The documented activity of this type of aquaculture activity around the Baltic Sea is the production of smolts for releases. These releases are partly releases to compensate for the blocking of rivers for the purpose of producing hydroelectric power. In Finland and in Sweden these compensatory releases are paid for by the electricity producing firms and based on water court decisions. There is also production of landlocked salmon for enhancement releases in the rivers. IBSFC obtains information from all Contracting Parties on their restocking plans and the number of salmon smolts released. In Denmark, Finland and Sweden there is a production of both brown and sea trout, for releases in lakes, rivers and in coastal waters. The objective of these releases are often to improve the recreational fisheries and the production are paid for by interested parties or through a license fee. In Finland there is also a large production of whitefish and pike-perch. Stocking natural waters in Germany is done for compensating blocking of the rivers (i.e. eel), and enhancement in rivers and lakes (eel, salmonids, cyprinids, pike, pike-perch) to the benefit of both, recreational and professional fishery. In Germany „put-and-take fishery" is the fishery based on stocking fish of edible size, which are caught more or less immediately (within few days) after stocking. This preferably was done in artificial gravel digging ponds. This type of fishery is not in accordance with animal protection legislation and is now strictly forbidden. In Estonia restocking is mostly carried out by local county governments and financed by Estonian Fisheries Fund or by Vortsjrve Fishermen association (eel). Main species stocked to inland waters are pike, eel ,pike-perch , (because in most waterbodies the balance between predatory and nonpredatory fish is out of balance)and brown-trout . Other species are carp and crayfish . Sea trout and white fish are the main species stocked to the coastal waters and salmon to the rivers. Age of stocking material is different: pike-perch, brown trout, whitefish and crayfish are one summer old; salmon and sea trout are two years old; carp is usually two summers old. The efficiency of restocking activities has been estimated very poorly. In Latvia 4,6 mill juveniles of salmon, seatrout, pikeperch, vimba and bream of different age and 13,6 mill. alevins and fry of pike and lamprey were released in 1997 in coastal and inland waters. Additionally evaluating the returns of reared fish releases from coastal and inland fishery it could be assessed that the fish stockings may benefit approximately 420 t of catch, including 325 t of salmon catch. Releasing of Baltic salmon smolts has been carried out to compensate the river damages and to increase sea ranching possibilities, providing additional resources for fishery in the coastal zone and Baltic Sea. Also stocks and catches of seatrout, pikeperch and vimba are supported by release of juveniles in the coastal zone. The pikeperch, river lamprey, bream and pike are stocked in rivers and lakes. In 80-s the eel juveniles were stocked in about 16 lakes, but at present these releases are stopped due to lack of financial means. Taking into account that the production of juveniles for stockings and farmed fish is of small quantities, it does not have any serious impact on the environment. The national fish resources restocking programme of Latvia is a part of the National Programme of Fisheries Development for years 1995-2010 where the release of fish juveniles and alevins of about 11.4 mill. pieces per year is planned. The restocking of reared salmon, seatrout, pikeperch, etc., will remain the leading branch of aquaculture. Modernisation of fish farms and methods could lead to some increase of culture of rainbow trout for local market. There is need for restructuring of aquaculture sector by using high-tech and introducing new fish species in culture, for example - whitefish, arctic char as well as crayfish. In Lithuania artificial spawning of pike, burbot, peled, rainbow trout, pikeperch, tench, carp, european whitefish, sea trout is carried out for stocking of natural water. White fish from lake Plateliu whitefish has been successfully introduced in other lakes. Glass and juvenile eels are being purchased for stocking. In 1995-1997 5.75 ha of spawning grounds were established or renovated in order to improve spawning conditions for salmonides. During the same period 12,45 ha of artificial spawning grounds for vimba were established. Some 320,49 thousand juvenile sea trout of various ages were stocked in inland waters in 1995-97. Technology of artificial spawning of broadclaws crayfish is implemented in the Simnas hatchery. Some lakes in the south of Lithuania have been stocked with 70,000 one summer old crayfish reared in its hatchery in 1997. The Danish contribution to restocking to the Baltic Sea is mainly consisting of releasing of juvenile salmon reared in a plant on the island of Bornholm and by the method „delayed release". The Government of the Russian Federation has adopted the Federal Programme for the development of the fishery industry „Fish". It includes a programme for aquaculture which also covers the Baltic area. In the Baltic area of Russia there are five fish rearing plants (Lugskiy, Nevskiy, Narviskiy and Svirskiy for salmon and Volkhovskiy plant for white fish). Besides of salmonids, such fish species as river lamprey, pike, bream etc. are reared at all fish rearing plants. Reared young fish is for restocking of rivers in the Baltic Sea basin and Ladoga Lake, as well as local basins.
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