RESTORING SALMON INTO OULURIVER Main results of the project OuLo,

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1 RESTORING SALMON INTO OULURIVER Main results of the project OuLo, Background The idea of restoring migratory fish upstream of the dams in the River Oulujoki has been raised since the successful completion of the Merikoski fishway at the river mouth in Preconditions for salmon migration and reproduction in this former salmon river have been surveyed in the project "Restoring salmon runs into Oulu and Lososinka Rivers", OuLo. The main target area has been the River Oulujoki but studies have also been made in the River Lososinka which runs through the city of Petrozavodsk into the Lake Onego in Russian Carelia. Salmon passage has been blocked in this small river for a long time period. The main aim was to survey the preconditions and possible means of restoring migratory fish runs into these two former salmon rivers. Another main aim was to create close co operation between Finnish and Russian experts, research institutes and authorities and to develop forms for action in realizing large projects in the different planning cultures of the two countries involved. The project got financial funding from Euregio Carelia Neighbourhood Program. Other funding was provided by the Council of Oulu Region, the Federation of Municipalities and Province of Kainuu, Fortum Power and Heat corp., the municipalities of Muhos, Utajärvi, Vaala and Paltamo and the City of Oulu. The project was part Oulu Kajaani Regional Development Zone. The project was coordinated by North Ostrobothnia Regional Environment Centre. The Finnish partners were Game and Fisheries Research Institute, University of Oulu, Finnish Environment Institute and Kainuu Regional Environment Centre. The Russian partners were Northern Fisheries Research Institute and Laboratory on the Problems of the Scandinavian Countries and Finland at the Petrozavodsk State University, and the Institute of Ecology and Evolution in the Russian Academy of Sciences together with Research laboratory "Hydroecology" in the Tver Technical University. Main results at the Oulujoki river Habitat surveys The focus of the habitat surveys in 2007 was in the tributaries Utosjoki, Kutujoki and Poikajoki. In the whole area, including the main river Oulujoki, a maximum of ca. 100 hectares of good or at least moderate quality habitats, suitable for salmon and trout juveniles, were found. In high discharges (>120 m 3 /s), the main river offers some hectares of flowing habitats with proper bed quality and velocity conditions. However, in low discharges, the flow ceases at the potential sites almost totally. The tributaries offer hectares of potentially suitable areas. The tributaries are not affected by the water level and discharge variation but their environments are somewhat deteriorated by the dredging of the river beds and the nutrient and suspended matter load originating from the catchment area. The potential habitats are shown in Figure 1 with more details in Figure 2.

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5 The results of salmon survival in general give support of continuation of the stocking to the tributaries, where grayling and brown trout reproduce already in the present state. In the main reach, the survival was poor and the availability of benthic invertebrates was also considerably poorer than in the tributaries (see Figure 5). Altogether 14 fish species were found in the electrofishing study in the main river study areas. Of salmonids, grayling, vendace and rainbow trout were caught. Egg incubation Tests measuring salmon egg survival were arranged in the tributaries of the River Oulujoki during the winter using both traditional equipment and the equipment developed by the experts in the Severtsov institute in Russia. Due to exceptionally high winter flood, silt was gathered into the boxes already in the beginning of the winter, which suffocated most of the eggs. Also a number of boxes were lost. The experiment is being replicated in Behaviour of adult salmon By means of radiotagging, the behaviour of adult salmon entering the river was examined in the lower reach of the river. Altogether 51 % of tagged adults entered the river through the Merikoski fishway, which indicates the stocking procedure; only a third of fish is stocked into the river area. Two male strayers were observed entering the River Muhosjoki. The individuals that most probably originated from stocking into the river from Montta, ascended in 1 2 days to the Montta dam and stayed there till spawning (Figure 7, blue line). Another type of searching behaviour was characteristical to some individuals, most probably originating from stockings to the Oulujoki delta area (Figure 7, red line). In Montta, most fish observations were made in the vicinity of the Montta hatchery (Figure 8). Figure 7. Two typical ascent patterns of adult salmon between the release site at the Merikoski fishway and the Montta dam upstream.

6 Figure 8. The observations of radiotagged salmon in Muhos in The percentages are shown for each year separately (kalanviljelylaitos = hatchery, Montan voimalaitos = Montta hydropower station). By changing the stocking practice, the behavior pattern of salmon could be changed. Observations of spawning salmon were made in Montta area and in the lower parts of the Merikoski fishway. Eggs were found e.g. in spawning nests found in the small brook at the Montta hatchery. Telemetry studies of smolts In 2007, three sets of radiotagged smolts were released into the river from Montta. Based on the results, the timing of the release has a great effect on the migration speed and the survival of the smolts (Table 1). Most of the smolts that did not reach the river mouth were most probably taken by pikes. The pikes, tagged with radiotransmitters, moved relatively short distances in general, and there was no time related difference within the summer season. They usually preferred to stay close to the river shores or shallow areas. Date of release (water temperature) Mean swimming speed km/day (min max) Survival percentage % (5,2 C) 1,8 (1,2 3,4) (6,3 C) 9,0 (2,5 22,2) (9,4 C) 25,9 (6,2 52,4) 95 Table 1. Survival and migration speed of three sets of smolts released into the river at different dates in May 2007.

7 Restorations and fishery infrastructure It is possible to compensate for the lacking habitats in the main river channel by taking into use the potential in the tributaries. Restorations have been made in Kutujoki and Muhosjoki during this project, and a restoration plan was made to Utosjoki. Pilot restorations were made in the main channel. In the electrofishings, no observations were made of adult salmon using them as spawning areas or of juvenile salmon using them as nursing areas. Habitat modelling showed that in the Iso Kauvansaari area of the main river, restoration measures would increase velocities and the flowing water areas significantly compared to the existing situation. The structures would create reproduction areas for both grayling and salmon. The amount of suitable habitats decrease as a function of decreasing discharge and increasing water level (Figure 9). Figure 9. The suitability of habitats in the Iso Kauvansaari modelling area for small salmon juveniles (<10cm) in various discharges and water levels. Upper graphs: discharge 50 m 3 /s, lower graphs: discharge 200 m 3 /s. Graphs on the left: water level 121,35 m, graphs on the right: water level 122,5 m. Since the amount of spawning and nursing habitats in the river area is much lower than before damming, the natural bypasses migh be usable in offering also good quality habitats. If they were constructed to all power plants, the total length would be 7.5 km. The amount and quality of existing fishery service structures and possible needs for their developent were surveyed in As a summary, it can be stated that near the city of Oulu there is pressure for recreational fishing and a growing demand for the infrastructure. Improving the existing struc

8 tures was suggested. There seems to be also a need for boat landing sites and restoring the areas of flowing water. As for Lake Oulujärvi region, the morphological state of the small rivers running into it seems to be poor and the areas suitable for juveniles are not effectively in use. By restorations, it is possible to improve these rivers and streams considerably. Plans for fish passage General plans for technical fishway solutions and transporting fish were created by EnviroCentre and for natural bypasses by the department of expert services in the division of water resources of Finnish Environment Institute, SYKE. The work was done under the guidance of the fishway work group. Three reports, one of them a joint report were produced. International experts, some of whom visited the area, gave their statements to earlier drafts of the reports. An international fishway conference was held in Rovaniemi in May 2007 in cooperation with the Council of Lapland. There are various solutions for fish passage at each of the dams. For each dam, the route for a natural bypass and the prioritized solution for a technical fishway were suggested in the summary report, see also Figure 10 for proposed locations of the bypass and technical fishway at each of the dams. Montta Pyhäkoski Pälli Utanen Nuojua Jylhämä Figure 10. Suggestions for proposed locations of the bypass (light blue) with technical sections at the entrance and exit (red), and technical fishway (dark blue) at each of the dams in the main reach of the River Oulujoki.

9 The advantage of natural bypasses is that they could offer also additional reproduction and nursery areas for the River Oulujoki. The technical solutions vary from vertical slot fishways to fish locks and lifts, depending on the dam. Transfering fish above the dams is suggested for some of the dams as one solution, but also to the first steps in restoring the salmon runs. A longer bypass is suggested to Montta Pyhäkoski as an option creating a maximum amount of habitats (Figure 11). Figure 11. Preliminary suggestion for Montta Pyhäkoski bypass. Blue represents the main alternative, red as an other possible option. Mortality during the downstream migration is not seen as a problem at the powerhouses of the main river reach, whereas the small Francis turbine at the Ala Utos powerstation is a threat for downstream migrating smolts. Therefore, a bypass for downstream migration is needed at this specific dam. Legislative preconditions and effects The legislative preconditions of fishway constructing, including the existing licences, were surveyed in The simpliest way to realize the fishways in the Ouluriver would be on a volunteer basis. A new organization would be required and agreements should be made on the areas and the discharge needed for the structures. This would not cause any changes to the existing obligations.

10 It would also be possible to change the fishery obligations of the power company, considering that there is an essential change in the circumstances or if the present obligation can be seen as inappropriate. The present obligations can be changed also by an agreement between the state and the power company. A third option is to change the fishery obligation partly to a fishery fee during a restricted time period. The fee could then be used as cofinancing the fishway constructing. All the latter options are more laborious than the first one, voluntariness. One possibility is, naturally, transporting fish upstream either temporarily or permanently. The permanent option is not recommended alone, since the reproduction areas are located between various dams and it is impossible to know where the fish should be transferred to. The risk for fish diseases in Oulujoki area is small if the number of ascending or transferred fish is small or the fish are transferred further away from the Montta hatchery. Social preconditions and impacts Social preconditions and a common wish were found in this subproject. There are also some doubts, e.g. reaching the natural life cycle. Restoring migratory fish runs into the Ouluriver is above all seen as act of justice and also part of environmental work in a wider scale. The inhabitants expect that the disadvantages of power production are diminished in all possible ways. Along with increasing leasure time, the value of the watershed for recreational use is growing. Restoring migratory fish into a heavily constructed river is action towards raising the river status and valuation. The improvement in the ecological state will raise the recreational value of the river, the attraction of the municipalities and the river area both as living, as holiday and as business environment, and, in the long run, also touristic attraction. In the long time scale, discussion is needed on the relation of creating fishery possibilities and the objectives of natural production of the migratory fish. Dissemination and future work The results of the project have been widely disseminated in local, regional, national and international scale. Together with the Council of Lapland, an international conference on fish passage was arranged in Rovaniemi in May The project final seminar was held in December 2007 and the final report publication will be published in the publication series of Finnish Environmental administration: Finnish Environment in late February More information in project Internet pages: The second phase of restoring the migratory fish into the River Oulujoki will be started as part of OuLu Kajaani development zone. The first step is drafting an agreement, in which the parties will commit themselves into the future work and in which the objectives, principles and time scale will be defined. The research done in the project has created basis for successive projects in Finland and in Russia. New networks will improve the possibilities for starting new joint projects in the future EU's program period. A stable network encourages other comparable projects in future and will also aid in changing information about current issues between the countries and different actors. Oulu, , Anne Laine, OuLo project leader

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