Tampere to Deploy Fyke Nets in April to Clear Iidesjärvi and Boost Birdlife

According to the City of Tampere, Tampere will resume fyke net fishing in Iidesjärvi this April to remove large numbers of rough fish and reduce internal nutrient loading and turbidity. Fyke nets will be set at predetermined sites to avoid disturbing nesting waterbirds and checked several times a week. Catches are used beneficially, and larger predatory fish are released.

City monitoring shows spring fyke catches have ranged from 3,150 to 8,430 kg, and the cumulative harvest since 2020 totals nearly 37.6 tonnes (578 kg/ha). That's a substantial haul for a lake this size.

Bird surveys indicate an increase in breeding pairs of water and shoreline species since management began, with 2025 recording the highest number of breeding waterbird pairs in the lake's monitoring history. Species showing clear increases include the great crested grebe, coot, common goldeneye and wigeon. Floating nesting rafts have supported a growing black-headed gull colony, with up to 120 incubating pairs.

Long-term nutrient trends are improving, but plankton, vegetation, fish communities and water quality still reflect an overall eutrophic — at times very eutrophic — condition. Tampere funds the measures and has applied for environmental authority grant support; the lake and its shore are proposed as a nature reserve in the city's 2026–2040 conservation programme. The city is also tackling stormwater at its source and monitoring effects with water sampling and continuous instruments.