Successful species protection on the Inn River: Near-natural dam maintenance boosts population of red-backed shrikes

The ecological maintenance of the VERBUND power plant dams on the lower Inn River is showing impressive results: the number of red-backed shrikes has quadrupled since the start of scientific monitoring in 2022. The number of nesting grounds has risen from 10 to 38, and the total number of individuals has risen from 28 to 125 birds.

The red-backed shrike—also known as the "butcher bird" or "nine killer” because it impales its prey on thorns to create food caches—has found ideal conditions on the Inn River dams. "By taking targeted maintenance measures, we have created a perfect mix of individual groups of bushes and species-rich dry grasslands," explains VERBUND ecologist Barbara Grüner. "The bird uses bushes as a lookout and nesting area, while the open areas offer it a high density of insects as a food base."

Elaborate maintenance makes biodiversity possible

VERBUND is implementing numerous environmental measures to improve the riverside landscape in the context of the EU-funded LIFE project "Riverscape Lower Inn River". This includes the development of high-quality meadows on the dams, which not only serve as technical facilities for retaining dams, but also offer important habitats for rare and protected species. Twice a year, over 100 hectares of grasslands—an area of more than 140 football fields—are mown over a length of around 40 kilometres. The removal of the mowed material ensures the necessary nutrient removal, while unmown sections of meadow serve as a refuge for insects.

This maintenance doesn’t just benefit the red-backed shrike: 57 species of wild bees were counted on the Simbacher Damm, including numerous butterflies and grasshoppers. The Inn River dams now form a flourishing ribbon along the river. There, species from the Alpine region such as alpine toadflax, coastal small-reed, fringed gentian and Swiss clubmoss grow. The intensive maintenance of the dams turns out to be a win-win situation: it serves to ensure stability and to promote biodiversity.

Although still relatively widespread in Bavaria and Upper Austria, the red-backed shrike is already on the ”near threatened” list of endangered species. In nesting areas, the primary threat to its survival is intensifying agriculture, which reduces its food supply of large insects. The project, which will continue until 2027, is not only monitoring the red-backed shrike but also other characteristic bird species, such as common sandpipers and little ringed plovers.

About the LIFE Riverscape Lower Inn River project

Under the Natura 2000 programme, the VERBUND-funded LIFE Riverscape Lower Inn River project aims to achieve the material nature conservation objectives of the Habitat Directive and the Birds Directive in the Lower Inn European Reserve.