European bison (Bison bonasus) in the Chornobyl exclusion zone (Ukraine) and prospects for its revival

In 2012–2016 a European bison adult bull was observed (by camera traps) in the Chornobyl Exclusion Zone (CEZ, Ukraine), west of Tovstyi Lis village. This is the first record of wild bison in Kyiv Polissya for over 300 years. The animal must have come from the Paliessie State Radioecological Reserve (PSRER, Belarus), having crossed the Pripyat river. The site where he was observed is 30–40 km from the locality where bison were introduced into the PSRER in 1996. The total area over which the bull has been observed is ca. 30–50 km2, and includes deciduous (oak, hornbeam, aspen) and mixed woodlands, and former grassy meadows now overgrown with birch, alder, aspen, pine. This constitutes the most favourable habitat type for bison available in the CEZ. The animal was only observed in February–March and August–October. Currently we are not able to judge how permanently the animal stays on this territory. Taking into account the amount of appropriate habitat in the region, size of the CEZ, protection regime and the fact that bison was a native species in the past, the CEZ could be the best area in Ukraine where a large free population of the European bison could be established.