Local habitat management and landscape-scale restoration influence small-mammal communities in grasslands

Ecosystem/habitat restoration has become a major goal of international biodiversity policy. However, restorations are often limited in space or time, and we know little on whether and how restoration and management affect vertebrates. Here we assessed the local and landscape-scale effects of habitat restoration and management on small-mammal communities in the Egyek-Pusztakocs marsh system (Hortobagy National Park, Hungary), site of the largest active restoration of grasslands on former croplands in Europe. We live-trapped mice, voles and shrews in spring and autumn in 2 years (four sampling periods) at two sites in six habitat types: croplands, grasslands restored 3-6 years earlier and natural grasslands. Data on 421 individuals of 12 species showed that restored grasslands were similar to croplands and natural grasslands in species richness, abundance and composition. At the local scale, management influenced abundance because there were more small mammals in unmanaged and early-mown grasslands with taller vegetation than in late-mown or grazed grasslands with lower vegetation, or in ploughed croplands. Elevation was also important because sites at higher elevation provided refuges during spring floods or summer droughts. At the landscape scale, the proportion of restored and natural grasslands positively affected the abundance of small mammals, whereas the proportion of linear habitats (roads, canals) had a negative effect on abundance. Our results show that management is more important than restoration per se at the local scale, which is expected for habitat generalists such as small mammals in contrast to specialists such as plant-feeding invertebrates. However, restoration provides landscape-scale benefits by increasing the area of grasslands that can serve as refuges for small mammals in unfavourable periods. We thus conclude that a mosaic of restored and appropriately managed grasslands with tall vegetation will provide the best chances for the persistence of small-mammal communities in dynamic landscapes.