Solar Panels as Novel Nest Sites for the European Paper Wasp Polistes dominula

Solar energy facilities are rapidly expanding in their land-use footprint worldwide, with significant implications for biodiversity. Although the impacts of conventional solar development are often negative for biodiversity, it is possible for some species to take advantage of the novel anthropogenic structures and microhabitats provided by solar facilities. We describe the frequent nesting of non-native European paper wasps (Polistes dominula) at two solar facilities in the Central Valley of California (USA), conducting nest censuses to further investigate population density and nest siting behaviour. Active nests were found to occur at a density of 10-23 per hectare of solar facility, and paper wasps had a preference for nesting in sheltered metal torque tubes compared with the more exposed undersides of photovoltaic panels. Our study shows that P. dominula might benefit from the construction of solar energy facilities, which could have a variety of impacts on native species and surrounding agriculture that warrant further study. The European paper wasp therefore provides an example to illustrate the potential for a varied and relatively unpredictable set of ecological outcomes to follow land-use change resulting from solar energy development.