Recurring fires in Mediterranean habitats and their impact on bats

Abstract

The pyrodiversity begets biodiversity hypothesis suggests that wildfires drive habitat diversification, allowing species with different niches to coexist and increasing biodiversity. However, despite numerous wildfires studies, limited research has addressed species-specific effects of fire recurrence. We radio-tracked grey long-eared bats (Plecotus austriacus) from the largest maternity roost (a historical monastery) in an area of the Mediterranean coastal belt with one of the highest fire recurrence rates. Although shrublands cover over 80% of the surroundings and P. austriacus is known to forage in a wide range of habitats, the tracked bats barely used this habitat. They spent 92% of their flight time in scattered small Aleppo pine forest fragments, and never visited any habitat patches that burnt more than three times in the last 30 years. We also report some of the longest foraging and commuting distances (9.95 and 10.5 km) from the roost described for the species in the literature. These results showcase how P. austriacus essentially forage in small forest fragments avoiding recurrently burnt areas, and highlight the colonies’ dependence on the monastery, probably due to limited alternative roost availability. This knowledge needs to be built on and accounted for in biodiversity conservation policies to ensure that species-specific responses to recurring fires in the Mediterranean are addressed.