Protected habitats support bats in Mediterranean dry grasslands.

The replacement of natural habitats by urbanization and agricultural land reclamation is one of the main drivers of biodiversity loss. Among European habitat types, natural grasslands are particularly prone to anthropogenic pressures, being also recognized as conservation priorities within the Habitats Directive. Nonetheless, little is known on the relationship between grasslands, their conservation quality, and most animals' taxa that may rely upon them. Here we focus on the role of Mediterranean dry grasslands protected by the EU legislation in sustaining bat populations, setting our study in the biodiversity hotspot of Mediterranean Italy. By conducting acoustic surveillance at 48 sites within a protected area devoted to conserve natural and semi-natural grasslands, we found that all the bat species found in the area are regular exploiters of such open environments. Grassland conservation quality, in terms of extent of high-diversity protected habitats, was the key factor shaping the use of grasslands by bats of all the considered guilds, together with several terrain and landscape features, which showed more guild-specific effects. Moreover, our results indicate that bat assemblages are functionally shifted along an ecological gradient from highly modified to well-conserved grassland sites, indicating a prevalence of opportunistic taxa in the former, and higher abundance of species of conservation concern in the latter. Overall, we demonstrate that the effects of EU-listed habitats may extend also onto bats in the case of Mediterranean dry grasslands, highlighting the importance of preserving such habitats as a tool for conserving highly mobile species.

Presence of humans and domestic cats affects bat behaviour in an urban nursery of greater horseshoe bats (Rhinolophus ferrumequinum).

Proximity to humans is a primary stressor for wildlife, especially in urban habitats where frequent disturbance may occur. Several bat species often roost in buildings but while the effects of disturbance inside the roost are well documented, little is known about those occurring in the proximity of roosts. We tested the effects of anthropogenic stressors on bats by monitoring reactions to disturbance in a colony of greater horseshoe bats (Rhinolophus ferrumequinum). We assessed disturbance by recording and quantifying the presence of people, domestic cats and noise sources near the roost. Disturbance outside the roost caused the disruption of roosting clusters; when cats entered the roost, bats decreased indoor flight activity. Emergence timing was delayed when people were close to the roost exit, and the delay increased along with the number of people. The occurrence of a cat increased the degree of group clustering during emergence. Cats entered the roost especially when young bats were present, and bat remains occurred in 30% of the cat scats we examined. We show that the occurence of human activities near roosts and free-ranging domestic cats are important albeit overlooked sources of disturbance.

Environmental drivers of parasite load and species richness in introduced parakeets in an urban landscape.

Introduced species represent a threat to native wildlife worldwide, due to predation, competition, and disease transmission. Concurrent introduction of parasites may also add a new dimension of competition, i.e. parasite-mediated competition, through spillover and spillback dynamics. Urban areas are major hotspots of introduced species, but little is known about the effects of urban habitat structure on the parasite load and diversity of introduced species. Here, we investigated such environmental effects on the ectoparasite load, richness, and occurrence of spillback in two widespread invasive parakeets, Psittacula krameri and Myiopsitta monachus, in the metropolitan area of Rome, central Italy. We tested 231 parakeets and found that in both species parasite load was positively influenced by host abundance at local scale, while environmental features such as the amount of natural or urban habitats, as well as richness of native birds, influenced parasite occurrence, load, and richness differently in the two host species. Therefore, we highlight the importance of host population density and habitat composition in shaping the role of introduced parakeets in the spread of both native and introduced parasites, recommending the monitoring of urban populations of birds and their parasites to assess and manage the potential occurrence of parasite-mediated competition dynamics as well as potential spread of vector-borne diseases.

Extraordinary range expansion in a common bat: the potential roles of climate change and urbanisation.

Urbanisation and climate change are two global change processes that affect animal distributions, posing critical threats to biodiversity. Due to its versatile ecology and synurbic habits, Kuhl's pipistrelle (Pipistrellus kuhlii) offers a unique opportunity to explore the relative effects of climate change and urbanisation on species distributions. In a climate change scenario, this typically Mediterranean species is expected to expand its range in response to increasing temperatures. We collected 25,132 high-resolution occurrence records from P. kuhlii European range between 1980 and 2013 and modelled the species' distribution with a multi-temporal approach, using three bioclimatic variables and one proxy of urbanisation. Temperature in the coldest quarter of the year was the most important factor predicting the presence of P. kuhlii and showed an increasing trend in the study period; mean annual precipitation and precipitation seasonality were also relevant, but to a lower extent. Although urbanisation increased in recently colonised areas, it had little effect on the species' presence predictability. P. kuhlii expanded its geographical range by about 394 % in the last four decades, a process that can be interpreted as a response to climate change.