Solar park on rewetted peatland records more bird species than nearby fields

A solar farm built on rewetted peatland in northern Germany hosts more types of birds than two nearby fields that are mown for hay, according to audio recordings collected at the site. The 30-hectare installation began construction in 2020 when the operator laid sand-and-gravel roads that blocked existing drainage ditches, allowing the former agricultural field to re-accumulate water and restore peat-forming conditions.

Researchers placed audio recorders across the solar park and the two comparison fields. Species richness was similar, yet the solar park recorded both wetland species such as white wagtails, reed buntings and grey herons and woodland species such as tree pipits and Eurasian tree sparrows.

Bird use of panels Meadow pipits, a grassland species listed as threatened in Germany, were photographed on the panels themselves. Birds of prey including buzzards and kestrels perched on the arrays while hunting mice in the grass below. The panels appear to substitute for shrubs and small trees, providing perches that are otherwise scarce in regularly mown hay fields.

Research context Hanna Rae Martens at the University of Greifswald said the combination of rewetted peat, reduced mowing and added perching structures contributed to the observed bird diversity. She noted that habitat was created for some endangered and wetland species.

Catherine Waite at the University of Cambridge said further studies are required to compare biodiversity at rewetted peatland sites with and without solar arrays. She added that incentives may be needed for wider adoption of the approach. The study is the first to examine bird communities at solar installations on rewetted peatland and was published in the journal Ecological Solutions and Evidence.