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The bat fauna of a 60 km2 wide area representing the typical rural landscape of inland Sicily and including the small “Rocche di Entella” karstic plateau (Natural Reserve and SAC) was surveyed between May 2006 and September 2007. Sampling was carried out at 95 sites, distributed proportionally in six main habitats. Bat calls were time-expanded with a D980 bat detector and then identified to species level by a Discriminant Function Analysis. We recorded 305 bat passes and identified 96.4% of recorded calls. Moon phase, cloud cover and their interaction did not affect total bat activity, nor did the sampling period. Aquatic and riparian habitats were preferred, whilst Eucalyptus plantations and vineyards were avoided. At species level, all bats selected the former habitats, except H. savii, and avoided field crops, except Myotis sp. Thermo-Mediterranean shrub formations showed the highest species richness, whereas vineyards had the lowest. Our study emphasizes the value of riparian habitats and low-intensity farming for bat conservation. Riassunto Preferenze ambientali dei chirotteri in un’area rurale della Sicilia. Il presente lavoro espone i risultati di un’analisi di selezione del habitat da parte della chirotterofauna in un’area di 60 km2 rappresentativa del tipico paesaggio rurale dell’entroterra siciliano e comprensiva del plateau carsico "Rocche di Entella" (Riserva Naturale e SIC). Da maggio a settembre 2006 e 2007, abbiamo effettuato campionamenti mediante bat detector (Pettersson D980) in 95 stazioni distribuite proporzionalmente alla disponibilità di habitat. I segnali sono stati identificati mediante Analisi della Funzione Discriminante. Abbiamo re- gistrato 305 passaggi, identificandone il 96.4% a livello di specie. Né la fase lunare, né la nuvolosità o l’interazione tra queste hanno influenzato significativamente l’attività di foraggiamento; nessuna influenza è stata inoltre rilevata rispetto al periodo di campionamento. Nel complesso la chirotterofauna ha evidenziato una preferenza per gli habitat acquatici e ripari, mentre le piantagioni di eucalipto e i vigneti sono stati evitati. A livello di singole specie, tutte hanno selezionato il primo habitat, con l’eccezione di H. savii, ed evitato i coltivi, con l’eccezione di Myotis sp. La più elevata ricchezza in specie è stata registrata nelle formazioni arbustive termo-mediterranee, la più bassa nei vigneti. Il nostro studio rimarca l’importanza della tutela degli habitat ripari e di un’agricoltura condotta a bassa intensità per la conservazione della chirotterofauna. doi:10.4404/hystrix-20.2-4444

Human-induced alterations of ecosystems and environmental conditions often lead to changes in the geographical range of plants and animals. While modelling exercises may contribute to understanding such dynamics at large spatial scales, they rarely offer insights into the mechanisms that prompt the process at a local scale. Savi’s pipistrelle (Hypsugo savii) is a vespertilionid bat widespread throughout the Mediterranean region. The species’ recent range expansion towards northeastern Europe is thought to be induced by urbanization, yet no study actually tested this hypothesis, and climate change is a potential alternative driver. In this radio-telemetry study, set in the Vesuvius National Park (Campania region, Southern Italy) we provide insights into the species’ thermal physiology and foraging ecology and investigate their relationships with potential large-scale responses to climate, and land use changes. Specifically, we test whether H. savii i) exploits urbanisation by selecting urban areas for roosting and foraging, and ii) tolerates heatwaves (a proxy for thermophily) through a plastic use of thermoregulation. Tolerance to heatwaves would be consistent with the observation that the species’ geographic range is not shifting but expanding northwards. Tracked bats roosted mainly in buildings but avoided urban habitats while foraging, actively selecting non-intensive farmland and natural wooded areas. Hypsugo H. savii showed tolerance to heat, reaching the highest body temperature ever recorded for a free-ranging bat (46.5 °C), and performing long periods of overheating. We conclude that H. savii is not a strictly synurbic species because it exploits urban areas mainly for roosting, and avoids them for foraging: this questions the role of synurbization as a range expansion driver. On the other hand, the species’ extreme heat tolerance and plastic thermoregulatory behaviour represent winning traits to cope with heatwaves typical of climate change-related weather fluctuations.

Intra-sexual segregation is a form of social segregation widespread among vertebrates. In the bat Myotis daubentonii, males are disproportionately abundant at higher elevations, while females are restricted to lower altitude. Intra-male segregation is also known to occur yet its ecological and behavioural determinants are unclear. We studied male segregation along a river in Central Italy where we tested the following predictions: 1. Upstream ( > 1000 m a.s.l.) males will rely on scarcer prey; 2. To deal with this limitation and exploit a cooler roosting environment, they will employ more prolonged and deeper torpor than downstream (< 900 m a.s.l.) males; 3. Body condition will be better in downstream males as they forage in more productive areas; 4. To cope with less predictable foraging opportunities, upstream males will use more habitat types. Consistent with our predictions, we found that prey were less common at higher altitudes, where bats exhibited prolonged and deeper torpor. Body condition was better in downstream males than in upstream males but not in all summer months. This result reflected a decrease in downstream males’ body condition over the season, perhaps due to the energy costs of reduced opportunities to use torpor and/or intraspecific competition. Downstream males mainly foraged over selected riparian vegetation whereas upstream males used a greater variety of habitats. One controversial issue is whether upstream males are excluded from lower elevations by resident bats. We tested this by translocating 10 upstream males to a downstream roost: eight returned to the high elevation site in 1-2 nights, two persisted at low altitude but did not roost with resident bats. These results are consistent with the idea of segregation due to competition. Living at high altitude allows for more effective heterothermy and may thus be not detrimental for survival, but by staying at lower altitude males increase proximity to females and potentially benefit from summer mating opportunities.