Introduction of the wood bison (Bison bison athabascae rhoads, 1897) in Central Yakutia

In April 2006, 30 wood bison from the Elk Island National Park (Canada) were brought to Central Yakutia. The group comprised 15 females and 15 males; 27 of them were underyearlings and two females and one male were over 1 year old. The animals started reproducing at the age of 2–3 years. Six calves were born in 2008; seven, in 2009; and nine (one calf died), in 2010. In 2008, the herd grew by 23.1%; in 2009, by 26.9%; and in 2010, by 30.8%. A comparatively high reproduction rate demonstrates their normal naturalization. In summer, bison feed on pasture forage and are provided with hay, haylage, and mixed feed in winter. Currently, the wood bison are successfully adapting to new environmental conditions with a short summer, extended winter season, and extremely low air temperatures in winter as the major factors. Their total population increased to 47 individuals, including 26 adults (55.3%) and 21 calves (44.7%) with a male to female ratio of 24 (51.1%) to 23 (48.9%). An extended reproduction of the bison stock in animal nurseries will contribute to their further natural settling in wildlife. In March 2011, a new batch of bison comprising 30 calves born in 2010 was brought to Yakutia, elevating their total population there to 77 individuals.