Understanding animal movement behaviour in dynamic agricultural landscapes – Agricultural disturbances

Agricultural landscapes cover significant areas across ecosystems worldwide. These spatially and temporally dynamic areas force wildlife to interact with agricultural machinery, and with sudden changes in resource availability during harvests and mowing events. Animals may avoid agricultural machinery and the changed habitat after management events to search for undisturbed habitat. Whether this search is successful depends on the landscape structure, which can influence the animals’ movement behaviour. Here we study how agricultural management events affect animal movement behaviour in two contrastingly structured agricultural landscapes. In 2014 and 2015 we collared 36 European brown hares (Lepus europaeus) with GPS-tags and accelerometers in a simple (large fields, few landscape elements) and a complex (small fields, many landscape elements) landscape in Germany. We recorded hares’ movement behaviour for 4 days before and after agricultural management events with (harvest and mowing) and without resource changes (e.g. application of fertilizer). We used four proxies for movement behaviour: the number of GPS points on the focal field, utilization range shift, utilization range size, and energy expenditure (measured as overall dynamic body acceleration). The results show that hares adjust their behaviour in relation to crop type, management type and landscape structure. We found more GPS locations on the focal field after the harvest of maize, rape seed and wheat, but not on grasslands. Hares showed longer utilization range shifts after management with and without resource changes. Utilization range size was only affected in wheat fields in the simple landscape. It increased after harvest and decreased after agricultural management without resource changes. Energy expenditure was unaffected by agricultural management. Hares profit from harvested fields, as they find food in form of fallen grains and improve their predator detection probability. The reaction to agricultural management events without resource change might depend on the precise type of management, as inorganic fertilizer can foster different movement reactions than liquid manure. Landscape structure plays an important role as utilization range sizes increase due to the necessity to reach distant alternative habitats. The provision of high crop diversity and set-asides with high quality forage throughout the year will help to increase hare and other farmland animal populations.