Bison reintroduction to Central Russia

Russian scientists are investigating the opportunity to bring wisents (Bison bonasus) back to the forests of Central Russia. Their effort has been funded by the Russian Foundation for Basic Research and the Federal Target Scientific and Technical Program called “Conservation of Rare Species”.

The story of rescuing wisents (Bison bonasus) which had been practically on the verge of extinction became classical and was included in schoolbooks. However, this does not mean that wisents are thriving. These animals’ position is still so unstable that they will perish without people’s constant care. In the meantime, the scientists are planning to bring wisents back to the forests of Central Russia. The specialists from the Severtsov Institute of Ecology and Evolution Problems (Russian Academy of Sciences) believe that this is feasible, but requires a competent wisent reproduction policy.

An all-sufficient stable wisent population should have the quantity of at least 500 head. Specialists of the International wisent group recommend a larger population of at least 1,000 animals. In Russia, it is possible to create such a totality of herds living at large in the territory of the Kaluga and the Briansk Regions and in the North-West of the Orel Region. It is there, in the National Park called “Orel Marshy Woodlands” and in adjacent territories, the first phase of the project is implemented to establish a large stable wisent population in the central part of Russia. This program has been supported by the World Wildlife Fund (WWF) and the Global Ecological Fund, it is also sponsored by E.S. Stroyev, governor of the Orel Region.

So far, the park territory of 36 thousand hectares is inhabited by only 68 wisents, out of which only 26 animals breed actively. The wisents are divided into 4 isolated groups, containing from three to twenty head. Forecasting the fate of the future population, the specialists carried out field observations in the park, studied archival materials, and even applied computer simulation of demographic and genetic processes.

Wisents are polygamic animals. Females start to reproduce at the age of 4 and bring posterity within 12 to 14 years. Childbearing age of male is even less – from 5 through 12 years, although some males may become fathers at the age of 15. Researchers’ estimations have proved that the largest group of the Orel Region wisents has good chances to reproduce themselves up to 100 head in 12 to 15 years given the lack of natural calamities, general epidemics and poaching: should the 100 head quantity is reached, the wisents will not be threatened by extinction from casual fertility fluctuations. Along with that, the group will preserve initial genetic diversity and will be able to avoid degeneration. The rest of the groups will remain in the demographic and genetic instability zone for the next 20 years, unless urgent measures are undertaken. The scientists suggest that the quantity of each of these groups should be increased up to 20 to 25 animals at the expense of bringing in new wisents. The Orel Region population possesses a sufficient level of genetic diversity for further stable development. For successful inhabiting of the National Park, it is very important to preserve each group of the Orel population, to promote stable and quick reproduction of the animals and continuous exchange of animals between the groups. For the time being, such a small herd lives in isolation, but the researchers hope that when the animals get more numerous, the groups will start contacting. That is quite possible as there are no hindrances in the territories inhabited by the wisents. Along with that, keeping in mind the previous experience in establishing wisent populations at large and the territory conservatism inherent in the species, the researchers should not expect these animals to disperse by themselves in the forests of the Kaluga and Briansk Regions. Six to eight similar populations are to be established to ensure bringing wisents back to the forests of Central Russia.