Movement behavior, space use and intraspecific interactions of cattle and horses: their role as mobile links in grassland restoration

Abstract Background Temperate grasslands and heathlands undergo degradation due to abandonment. Large grazers play a vital role in the restoration of these habitats, acting as mobile links that connect intact with degraded sites in space and time. Improved knowledge of grazers’ movement patterns and space use is required to understand movement in relation to ecological changes and management plans for optimal restoration success. Methods Our study took place in the former military training area Oranienbaumer Heide, central Germany, where cattle and horses were used to counteract abandonment through grazing. We analyzed a 15-year GPS-tracking dataset with high temporal and spatial resolution to explore the year-round movement behavior, space use, and intraspecific interactions of grazers. We used hidden Markov models to classify behavior, which was analyzed in relation to species, seasons, and distance to water sources. We further analyzed space use in terms of movement distance, diffusion rate and home range size using continuous-time stochastic movement models. Lastly, we quantified intraspecific interactions within cattle and horse populations, especially in relation to the separation and consolidation of management units within our study area. Results We showed that cattle were more selective in choosing resting and grazing areas compared to horses. Grazers’ space use revealed that cattle displayed more extensive movement, with greater distances covered, more exploration, and larger home ranges. Both species presented clear seasonal movement patterns. Thereby, cattle remained closer to water sources than horses, especially during summer. Intraspecific interactions differed between species and likely limited mobile link function in horses, as horse herds remained largely separated after fences between management units were removed, while cattle herds consolidated into a single group. Conclusions Both cattle and horses serve as effective mobile links in ecosystems. However, interspecific differences in grazing behavior, space use, and intraspecific interactions can lead to distinct outcomes in grassland restoration. To harness the complementary strengths of each species, mixed-grazing management should be favored whenever possible to maximize restoration benefits.