Status of Savi's pipistrelle Hypsugo savii (Chiroptera) and range expansion in Central and south‐eastern Europe: a review

Savi's pipistrelle Hypsugo savii is a Mediterranean faunal element among the bats; it occurs in southern Europe, the Canary Islands, north‐western Africa, most of the Mediterranean islands, in the northern part of the Middle East, in the Crimea, Caucasus, West Turkestan, and northern Afghanistan. The northern margin of its geographical range in Europe reaches the Pyrenees, Massif Central, southern Alps, Dalmatia, Balkan Mountains and southern Crimea, like that of other similar biogeographical elements. Since the 1990s, Hypsugo savii started to be found in inland areas of south‐eastern Europe and in Central Europe as far northwards as in central Bohemia and southern Poland. These numerous new occurrences seem to be either 1) connected to environmental changes caused by the current climate change; 2) evidence of an intrinsic expansion process powered by the species' synanthropic tendency, including passive human‐mediated transport; or 3) a reflection of the increase in field survey efforts. Distributional data on Hypsugo savii from central and south‐eastern parts of Europe were gathered and evaluated. We provide a detailed review of all records available by the end of 2013. The assessment of temporal distribution of the data clearly shows an ongoing and relatively fast expansion of Hypsugo savii from southern to Central Europe, which represents a shift of almost 800 km northwards in the last 20–25 years. Most of the records (65%) originate from urban habitats. This suggests that the synanthropic habits of the species are the most plausible explanation for the northwards shift of the range limits of Hypsugo savii.