FINLAND

by

Outi Heikinheimo-Schmid, Markku Pursiainen, Kai Westman,
Pekka Tuunainen and Aimo Järvinen ¹

Introduction

Finland's inland waters cover 31 000 km², which is about 9.4 % of the country's total area. There are over 60 000 lakes, 17 of which have a surface area of more than 200 km² each. The lakes are shallow, the average depth being 7 m; their total volume is 220 km³. Together they have a total shore length of 130 000 km. Nearly one hectare of lake area and about 30 m of shoreline are available per capita of the population (4.9 million in 1984). The total length of the rivers exceeds 20 000 km.

The new fishing law (1983) expanded fisheries administration to include eleven districts, each headed by a fisheries biologist. Each district is divided into uniform fishing areas in order to facilitate regional planning of the fisheries and their management.

In 1984 some 541 000 people were engaged in fishing in inland waters. About 2 500 of them were professional or semiprofessional fishermen and the rest fished for recreation and their own use.

The total catch from inland waters was estimated at about 30 000 tons in 1984. This was about 20 % of the total catch for the country (Appendix 1).

The commercial catch in 1984 was 5 400 tons (Appendix 1). The main species in the catch are perch, pike, vendace and roach.

Damming of rivers and water level regulation of lakes and reservoirs, mainly for hydro-electric power generation, have created severe problems in fisheries management. Due to extensive water protection measures, pollution of waters has strongly diminished. About 130 km² of the lake area in Finland, i.e. 0.4 %, is badly polluted by industry or sewage, and in 20 % of the lake area the water quality is classified at satisfactory or passable.

Extensive fish stocking programs form the main part of the management of economically important fish stocks. The total number of fish released in 1984 was 45 million (excluding newly hatched fish), more than 75 % of these were whitefish. During 1982–1984 the number of fish used for stocking rose by nearly 30 %, mainly due to increased whiteüfish stocking (Appendix 2).

Production of rainbow trout for human consumption has grown by 50 % since 1982, being 9 500 tons in 1984 (Appendix 2 ).

The EIFAC National Committee, chaired by the EIFAC correspondent for Finland, is responsible for liaison between EIFAC and Finland and works on subjects of current interest to EIFAC.

¹ Finnish Game and Fisheries Research Institute, Fisheries Division, P.O. Box 193, SF-00131 Helsinki 13, Finland.

I FISHERIES BIOLOGY AND MANAGEMENT

1. Economic aspects of commercial and recreational fisheries

In 1984, the value of the total catch from inland waters (30 000 tons) was 183 million FIM (30 million USD). This was 43 % of the value of the total catch in Finland in the same year.

The value of the total catch from inland waters taken by professional fishermen (5 400 tons) was 33.2 million FIM (5.5 million USD) in 1984, two thirds of which was due to the vendace catch.

Vendace is the most important fish species in the catch of the commercial fishery in inland waters, with annual catches of about 4 000 tons during the 1980s. As regards other species, the Lokka and Porttipahta reservoirs in northern Finland have become to remarkable professional fishing areas for e.g. whitefish and pike.

The annual profitability of commercial fisheries is studied by means of daily records kept by some 70 fishing households or enterprises in inland waters.

A study on the use of the professional fish catch was published in 1984. About half of the domestic fish used as human food is processed, but the fish from inland waters is mostly used fresh. The proportion of inland fish used as animal feed is insignificant (62).

Subsistence and recreational fishing is of great economic and social significance in Finland. Perch and pike are the most important species in the catch of subsistence and recreational fishermen. More than half of the catch is taken with gill nets. In 1984, the value of the catch (24 400 tons) was 149 million FIM (25 million USD).

A personal fishing licence (19 FIM from 1.1.1985) and the permission of the water owner are generally required for every kind of fishing, but district licences enable angling with natural bait and ice fishing with rods without the permission of the water owner.

In 1984, the annual catch of the native crayfish (Astacus astacus) was estimated at about 2.5 million individuals, the value of which was 17.5 million FIM (2.9 million USD).

The inquiry concerning subsistence and recreational fishing made in 1984 will give the first more accurate estimate of the crayfish catch, because in 1983 a general fishing licence became obligatory for crayfish fishing as well.

The lamprey catch in 1983 was 2.3–2.4 million individuals, which is about 100 tons. The value of the catch was estimated at 4.3 million FIM (800 000 USD).

The number in brackets (   ) refers to the number in the bibliography.

2. Survey and appraisal of inland waters

So far fish stock assessments have been published from eight Finnish lakes and the coastal area, the main species assessed being vendace, whitefish, perch and pike. In five lakes studies were continued on the population dynamics and causes of year class fluctuations in the vendace (Coregonus albula), which is the most important species for the commercial fisheries in lakes. A research program was continued by the University of Turku with the support of the Academy of Finland, on the ecosystem in Lake Pyhäjärvi, Säkylä, which is the most productive vendace lake in Finland (annual catch 20–40 kg/ha). A study on the present state of the fisheries in Lake Saimaa, East Finland, was published in 1984 (51).

The echocounting method for estimating fish numbers, developed within EIFAC, has been used in seven lakes in Finland during 1984 and 1985. Finland also participated in the echocounting experiment on Lake Tegel, which was a part of the EIFAC program, International Intercalibration Exercise on Fish Sampling Methods in Lakes.

During the intersessional period, extensive research programs for planning regional fisheries management have been in progress. The report on a three-year investigation of the fisheries system in Lake Oulujärvi was published in 1985 (52, 53).

3. Management of inland waters

3.1 Restoration of waters

Restorative measures have been carried out in about 30 rivers in order to increase fish and crayfish production and improve the fisheries. At the same time follow-up research programs have been continued, to study the results of the restorations.

3.2 Stocking

Fish stocking is the most common management method used in Finland. In 1984 the number of salmonids (Salmo and Salvelinus sp.) released at the age of one summer or more was 6.3 million. The corresponding number for whitefish species (Coregonus sp.) in 1984 was 34.8 million and for other fish and crayfish species 4.0 million. These last two groups are mostly stocked as 1-summer-old fingerlings (See also Appendix 2). It has lately been estimated that the value of the yearly input of whitefish, salmon and brown trout is about 40 million FIM (7 million USD). This stocking gives a yearly catch of 3.5 million kg of these fish species. The value of the catch is about 80 million FIM (13 million USD), i.e. about double the value of the stockings.

A number of transfer stockings have also been done with some fish species other than those mentioned in Appendix 2 and also with crayfish (Astacus astacus) and lamprey (Lampetra fluviatilis).

3.3 Marking and tagging

To evaluate the stocking results, and for research purposes, some 87 500 salmonids were tagged with Carlin tags in 1984 and about 125 200 in 1985. The corresponding numbers for other fish are 10 400 and 4 800. In addition, about 311 500 salmonids and 578 200 other fish, mostly whitefish, were marked with microtags (“nose tags”) in the two years.

The Finnish Game and Fisheries Research Institute handles all the returns of Finnish tags. Computers are used to store the data, deal with correspondence and payment orders, and compute the tagging results (yield, etc.). The number of tags handled annually is around 10 000. In 1985 the recovery register contained 75 000 records.

3.4 Introductions

No new fish or crayfish species were introduced into Finland during 1984–1985. Elver introductions will propably begin in 1986, which means that the continuously decreasing eel catch may be expected to improve in future years. Before introduction the elvers will be kept in quarantine, to prevent the spread of fish diseases.

4. Research programs shared with other countries

Cooperation has been continued between Finland and the neighbouring countries. In the Tenojoki (Tana) River on the Finnish-Norwegian border, the yearly studies on the Atlantic salmon (Salmo salar) stock include preparation of catch statistics, catch sampling, and assessments of parr densities. In 1984, the joint studies on salmon were extended to the Näätämöjoki (Neiden) River.

The Finnish-Soviet Border Water Commission has continued its work on questions concerning the fisheries of the waters in the border region, chiefly Lake Inari and Lake Pyhäjärvi (Karelia). In Lake Pyhäjärvi, comparisons were made between the fish stocks on the Finnish side, which are under heavy and constant fishing pressure, and those in the Soviet area, where fishing pressure is insignificant. A final report on the results from Lake Pyhäjärvi will be given in 1986, and monitoring will continue. Finnish-Soviet cooperation was continued in investigations on salmonid smolt production in Finnish and Soviet Karelian rivers. Finland also participates in the research program on Lake Säämäjärvi and the Rybinsk Reservoir in the Volga River, in which echocounting is used.

Research on the fish stocks and fisheries in the Tornionjoki (Torneå) River was continued in cooperation with the Finnish-Swedish Border River Commission and the Swedish fisheries authorities. A report on the Finnish investigations was published in 1985 (38).

Liaison has been continued with inland fisheries researchers in Poland, the main subjects being fish culture, and research on whitefish, vendace and sea trout.

5. Other subjects

The report of the Working Group on Enhancement of Migrating Fish Stocks was given in 1985. The foremost measures should be construction and improvment of suitable habitats for migrating fish. The working group gave a list of the areas which need restoration, ranked in order of urgency, and both short-term and long-term programs for restoration measures (59).

II FISH CULTURE AND DISEASES

1. Fish culture

1.1 Fish farms and the production

The rainbow trout is practically the only fish species farmed for food in Finland. In 1984, 335 farms produced 9 500 tons of fish for human consumption. More than half the total amount is produced in brackish water in net cages (See Appendix 2).

Fish for stocking purposes are reared either by intensive methods in artificial tanks or earth ponds (mostly salmonids) or by extensive methods in large ponds with a natural food supply. Many of the farms that produce rainbow trout also produce other salmonids for stocking. In 1984, the number of salmonids produced for stocking purposes, excluding newly hatched juveniles, was 6.3 million (41 % for inland waters). The total area of the natural-food ponds in that year was 8 500 hectares and their production was 38.7 million (Appendix 2).

In 1984, the state fish farms (10 in operation and 4 in the construction and planning phase) belonging to the Finnish Game and Fisheries Research Institute produced some 139 million whitefish eggs, 11 million salmon eggs, 16.2 million brown trout eggs and 1.0 million char eggs for rearing juveniles for stocking. The production of pike-perch fry increased rapidly in the 1980s, exceeding 6 million in 1985.

1.2 Economic evaluation of aquaculture

If producer prices are used, the total value of the aquaculture products in 1984 was 269 million FIM (45 million USD), of which 204 million FIM (34 million USD) consists of rainbow trout for human consumption and the rest of stocking material. Since 1982 the value of aquacultural products has increased by over 60 %.

1.3 Fish nutrition research

The dry fish feeds used in 1984 amounted to almost 23 000 tons. Low value fish and Baltic herring form a fairly important part of the fish feeds, especially in brackish-water net-cage farming.

Fish feed development is continuously researched in cooperation with feed producers and farmers. The main goals are to improve fish growth and feed conversion, to reduce the waste nutrients originating from feeds, and to examine the effects of the feeds on the quality of fish for human consumption and on the quality of stocking material. New types of fish feeds are also needed for intensive cultivation of non-salmonid species.

1.4 Development of aquaculture technology

In recent years the research in aquaculture technology has concentrated on comparative testing of the physiology of stocking material reared under different conditions. The main factors examined at the fish farms have been rearing basin shape and current conditions, feeding technology (development of automatic feeders and feeder processors), illumination and use of warm water and heated effluents.

To avoid selection caused by cultivation from generation to generation, brood stocks are primarily based on the natural spawn of known native or released fish stocks. On the other hand, a rainbow trout breeding program has already been planned and a new fish farm will be built especially for this purpose (55).

The problems caused by long distances between fish farms and stocking sites are nowadays partly avoided by better transportation techniques and by using release ponds in the most important stocking sites. In these ponds or basins, fish are able to recover safely from transportation before they are released (39).

2. Fish and crayfish diseases

The official fish health programme maintained by the National Veterinary Institute has continued, and by the end of 1985 the number of fish farms belonging to it has risen to 117.

Vaccination has significantly reduced outbreaks of vibriosis (Vibrio anquillarum) and the need for antibiotics in 1984–1985, in spite of the large increase in fish farming production. However, outbreaks of contagious dermatitis (Aeromonas salmonicida var. achromogenes) are occurring increasingly frequently in coastal rainbow trout farms.

Two pathogens were recognized for the first time in Finland in 1984. The virus for IPN (infectious pancreatic necrosis) was isolated from a one-year-old rainbow trout suffering from vibriosis on the southern coast. However, no clinical symptoms specific to the infection could be observed. A mild outbreak of enteric redmouth disease (Yersinia ruckeri) was diagnosed in salmon and whitefish in northern Finland and caused some mortality (50).

In natural fish stocks, lymphoma of pike is the most prevalent disease in coastal waters. The information accumulated indicates that the prevalence is not connected with pollution but is highest in areas where the pike is living at the extreme limit of its salinity tolerance.

Some new cases of crayfish plague appeared in 1984–1985. Research on plague resistant signal crayfish as plague spreaders has continued. In fact, under culture conditions, juvenile signal crayfish have shown rather high plague mortality. Haemolymph studies on Aphanomyces -infected crayfish and signal crayfish have continued (17).

The number of finds of the parasite Psorospermium haeckeli has risen to five in southern Finland. The haemolymph values of infected crayfish are under study.

III FISH AND POLLUTED WATER

1. Fish farm effluents

The most serious factor limiting the expansion of aquaculture in Finland is the eutrophication caused by the fish farm effluents, especially the phosphorus. The total phosphorus loading from fish farms in 1982 is calculated to be 90 tons. For comparison, the phosphorus load originating from industrial waste waters is 644 tons a year.

An effective method of reducing the amount of waste phosphorus is to minimize the phosphorus content of the dry feeds. At its best, the present level is about 0.9 %. Removal of waste solids by using self-purifying rearing basins and a whirling separator gives a further marked reduction of waste phosphorus. Even better results can be achieved by using industrial sieving equipment and flotation, but this method is rather expensive at present.

2. Biological monitoring

Toxicological and physiological methods of evaluating the effects of effluents on fish at different stages of development are available for administrative use. Biological monitoring is playing an increasing role in environmental protection in Finland.

Standard national methods are available for using fish and the cladoceran Daphnia in acute toxicity testing. Long-term toxicity testing methods are being delevoped.

Water quality criteria have been prepared for fishing waters and will be evaluated over a period of some years.

International cooperation with the Helsinki Commission, ICES and OECD continues in this field.

3. Bioaccumulation of toxic substances in fish

A national program for monitoring the concentrations of chlorinated hydrocarbons and heavy metals in fish has been in progress since 1978. More is now known about the presence of chlordanes, toxaphenes and polychlorinated dioxines and dibenzofuranes in fish. Extensive research carried out during the last three years has revealed that air-borne pollutants may be the main reason for the high mercury concentrations in fish in waters unaffected by discharge of wastes.

Although the direct release of mercury into the water has been greatly reduced since the late 1960s, the mercury contents in fish are still a severe problem in Finland. In almost half of the Finnish lakes the mean mercury concentration of predatory fish (pike and burbot) exceeds 0.5 mg/kg, which means that consumption of these fish should not exceed 0.5 kg/week (27, 61).

4. Acidification of inland waters

At the beginning of 1985 the Finnish government initiated a 5-year research project on acidification due to air pollution. The fisheries part of this project is conducted by the Finnish Game and Fisheries Research Institute in cooperation with the University of Helsinki. Data on fish populations and water quality were collected from 75 small lakes in different parts of Finland. According to preliminary results, the fish populations of several small acidified lakes in the southern coastal area of the country are sparse. The effects of acidification on fish, including the effects of heavy metals in precipitation, are being examined in both laboratory and field experiments, special attention being paid to the reproduction of fish (46, 47).

5. Physical habitat modification

Methods have been developed for evaluating the effects of habitat modification on fish stocks and the results of management measures. In 1985, guidelines were published in order to unify the procedures (7, 37, 70).

In 1984 a report was published on a three-year research program concerning the effects of the dredging and land-drainage in the Kyrönjoki River on the fish and crayfish stocks and the fisheries in the river estuary and in the sea area outside the river mouth (9, 15, 40).

Acknowledgements

The information for this country report was obtained from the members of the EIFAC National Committee for Finland and many other specialists in different fields. We wish to thank all of them for their contribution, and Mrs. A. Damström for checking the English language.

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APPENDIX 1

FISHING IN 1984,     Catch 1 000 kg

APPENDIX 2

KALANVILJELY VUONNA 1984 — FISKODLING ÅR 1984 — FISH CULTURE IN 1984

1) Tuotannosta kirjolohta 99 %. Jäännös lohta ja taimenta. - Av produktionen 99% regnbågslax.
Resten lax och öring. - 99 % of production rainbow trout. The rest salmon and brown trout.

2) Tuotantoluvut perkaamatonta painoa. - Produktionssiffrorna som orensad fisk. Production in kg ungutted fish.

3) Lohi-, taimen- ja nieriälajien osalta syömäänoppineita, vapaasti uivia poikasia. - Beträffande lax, öring och röding, yngel som börjat äta och simmar fritt.- Salmonids free-swimming fries.

4) Hauen osalta esikesäisiä, muutaman viikon ikäisiä poikasia. - Beträffande gäddan nykläckta, några veckor gamla yngel. - Pikes a few veeks weeks old younglings.

Istutustuotannon arvo 1984 M mk 65,0
Utsättningsproduktionens värde 1984 M Fmk 65,0
Value of stocking-production 1984 M Fmk 65,0