25.11.2025
A comprehensive restocking programme for small juveniles of salmon and sea trout has been drawn up in the Iijoki river basin. The programme gathered up-to-date information on the suitability of different sites for the planting of small juveniles. With the help of restocking, salmon fish stocks stigmatised in the Iijoki River and its tributaries are formed in the area.
Extensive surveys were carried out for the planting programme in Iijoki, Livojoki, Pärjänjoki and Loukusanjoki. In addition, expert and literary knowledge was utilized. For each site, the location, the size of the nursery area, an estimate of the nursery production and accessibility by different means of transport are presented. The programme also determines flow rates, hail sizes and depth variations of river beds, and assesses shading, coastal vegetation, benthic fauna and aquatic vegetation.
“The Iijoki main channel surprised positively, as did most of the tributaries. Locally, challenges were identified in the Livojoki river in terms of solid load. In part: potential for increasing juvenile production through current water remediation was identified in the surveyed sites. Estimates of planting rates for newly hatched, pre-summer and one-year-old chicks were prepared for the sites, based on the areas of the sites surveyed, the results obtained and previous survey data.’, According to an environmental expert Marleena Isomaa Eurofins Ahma Oy.
Fisheries Specialist with good knowledge of the Iijoki river basin Eero Hartikainen Metsähallitus states: ‘The restocking of juveniles has hitherto been carefully planned, but the restocking programme now completed will make it possible to restock small juveniles of salmon and sea trout with greater precision. The planting programme is a visually and substantively clear entity, which facilitates the planning and targeting of plantings.’
The planting programme was prepared by Eurofins Ahma Oy. The consultant was supported by a planning team consisting of experts from the Regional Council of Northern Ostrobothnia, Natural Resources Institute Finland, Metsähallitus, PVO-Vesivoima Oy and Voimalohi Oy.
The young planting programme is part of the Lohi Iijoki 2 project. Other measures in the project include, for example, a smolt monitoring study in Livojoki/Iijoki Haapakoski, underwater camera monitoring of smolts in Haapakoski, the development of the downward migration route of smolts in Haapakoski, over-transfers of rising fish and smolts, and the restocking of small juveniles.
The Lohi Iijoki 2 project is implemented by PVO-Vesivoima Oy, the Lapland ELY Centre, the Ministry of Agriculture and Forestry, Ii, Oulu, Pudasjärvi, Taivalkoski, Kuusamo, the Regional Council of Northern Ostrobothnia, the Iijoki fishing area, Metsähallitus, Voimalohi Oy, the North Ostrobothnia ELY Centre and the Natural Resources Institute Finland. The project is managed by the Regional Council of Northern Ostrobothnia. The project will run from 9 January 2024 to 31 October 2026. In addition, the Natural Resources Institute Finland participates in smolt monitoring studies with separate project funding from the Ministry of Agriculture and Forestry.
The Lohi Iijoki 2 project has received funding from the NOUSU programme of the Ministry of Agriculture and Forestry. The programme improves the living conditions of migratory fish and aims to restore the natural reproduction of migratory fish stocks in Finland's current waters.
Additional information:
Mirko Laakkonen, Project Manager, Lohi Iijoki 2 project, Regional Council of Northern Ostrobothnia, tel. +358 40 685 4036, mirko.laakkonen(at)pohjois-pohjanmaa.fi
Link: The young planting programme is available for download the Lohi Iijoki 2 project.
