Population Trends of Cave-Dwelling Bats in the Eastern Iberian Peninsula and the Effect of Protecting Their Roosts

Abstract

Populations trends of cave-dwelling bats in the Eastern Iberian Peninsula and the effect of placing a perimeter fencing around their roosts (to avoid human disturbance on breeding colonies) were evaluated from 1997 to 2014. The species with the highest relative abundance was Miniopterus schreibersii (62.4%), followed by Myotis myotis/blythii (18%), and both populations showed positive trends. On the other hand, Myotis capaccinii (6.2%), M. escalerai (4.8%) and M. emarginatus (0.9%) showed significant, but minor increases, particularly in recent years. Rhinolophus mehelyi (0.2%) displayed no significant trends, while a moderate population decline was recorded for R. euryale (5.1%). Rhinolophus ferrumequinum (2.2%) and R. hipposideros (0.1%) showed positive growth trends. The main assemblages in the evaluated roosts were formed by Myotis myotis/blythii, Miniopterus schreibersii and R. ferrumequinum. This denotes their less specific requirements or greater flexibility when selecting roosts, compared with oth...