Shifts in habitat associations of dung beetles in northern Spain: climate change implications

We examined whether dung beetle species shift their habitat associations (vegetation types) with different climatic conditions, using altitudinal and seasonal gradients as analogues of future climate change scenarios. Dung beetle assemblages in Picos de Europa (northern Spain) were monitored by dung-baited pitfall trapping in three vegetation types (woodland, heathland, and pasture), three altitudinal zones (520-600 m, 950-963 m, and 1,230-1,275 m) and during two different seasons (summer and autumn) in 1994. Most species shifted their habitat use on the altitudinal and seasonal gradient in response to changes in microclimatic conditions (temperature). They were generally associated with heathland and woodland (shaded habitats) at lower altitudes, but they were increasingly associated with pastures (open habitat) as altitude increased. There was also a greater association with pastures in the coldest season (autumn) and with heathland and woodland in the warmest season (summer). These results suggest that climate change could be a major factor influencing habitat selection in dung beetles. The magnitude of habitat shifts was species specific, so climate warming also has the potential to generate new or different species interactions. The research presented here supports the feasibility of using microclimatic gradients within a region to study the potential effects of future climate change on both species and communities.