European bison in the Uzhanskyi National Park (Ukrainian Carpathians): formation of a new local population

The history of the disappearance from natural habitats of the European bison (Bison bonasus) and restoration of its populations in the Ukrainian Carpathians is described. The appearance of the European bison in the territory of the Uzhanskyi National Nature Park, which is part of the international biosphere reserve ‘Eastern Carpathians’, is considered. The area where the bison appeared is adjacent to Poland and Slovakia, and its migration routes cross the Ukrainian–Polish–Slovak border. The paper describes and summarises all cases of observation known to the author to date of individuals of the European bison and traces of their presence in the biotopes of Uzhanskyi National Nature Park, as well as the results of monitoring using camera traps from 2021 to winter 2025. Photographic evidence of bison individuals was obtained, which became indisputable proof of the presence of this species in the Park. The migration routes of these animals pass in two directions: in the south-east—from the Slovak National Park ‘Poloniny’; and in the northwest—from the Polish National Park ‘Bieszczady’. There is a trend of the bison returning to the forests of the Uzhanskyi NNP. Cases of observations have become more frequent not only of their traces but also of the animals themselves. At present, bison enter the Park’s territory in different seasons: in summer, autumn, and in winter of 2025; some individuals remained to winter. Due to favourable climatic conditions, sufficient food reserves, and low anthropogenic load, there is a high potential for the settlement of the European bison and the formation of its stable transboundary Uzhanskyi subpopulation. The bison can play an important role in the functioning and maintenance of the diversity of natural ecosystems of the Uzhanskyi NNP, and its appearance has further raised the conservation significance of the territory of the Park. At this stage, it will be important to continue to monitor the spatial distribution of animals, to establish the age and sex structure of the emerging population (if the process of bison acclimatisation continues), as well as its numbers, and to establish its transboundary migration routes in adjacent territories.