Small, scattered, but resident, populations of Golden Jackal Canis aureus occur along the coasts of the Balkan Peninsula. The bulk of these European Jackals is concentrated in the eastern parts of the Peninsula, mainly in Bulgaria. The northern border of the resident population lies along the Danube in the Walachian Plain of Romania, and in Srem (Yugoslavia). Vagrants may appear far outside the Balkans in north‐eastern Italy, Slovenia, Austria, Hungary and Slovakia. Whilst the species is in decline in Greece, it has expanded its area in Bulgaria from = 2400 km2 in 1962 to 80 000 km2 in 1985, i.e. a 33‐fold range increase within 23 years.

In the present study, we analyzed 58 samples of the lesser white-toothed shrew group (Crocidura suaveolens) from eastern Europe and Turkey, where, according to previous publications, three different mitochondrial and nuclear lineages are present. We sequenced 799 bp of the nuclear BRCA1 gene and 400 bp of the mitochondrial cytochrome b gene to: (1) determine a potential contact zone between the lineages; (2) detect hybridizations and introgressions between them; and (3) comment on the level of reproductive isolation of the different lineages. We revealed two zones of hybridization in Turkey, of which the first occurred west of the Bosphorus Straits (three hybrids) and the second in Anatolia (twelve hybrids). In the latter, the nuclear markers revealed a large zone of hybridization, of approximately 600 km. It also revealed that hybrids of first, second, and later generations are present within the populations, and therefore that the reproductive isolation between the different lineages is weak.