January
High winter. Bisons are gathered near the feeding sites. The food is prepared by the workers of Białowieża National Park and it is put at special, the most convenient places for bisons. During winters bisons have problems with satisfying their thirst because the water reservoirs are often frozen. Animals solve this problem breaking the ice with their bodies. Apart from walking to look for water, bisons don’t walk much at that time.

February
Herds of about dozens bisons stay near the feeding sites but some of them make smaller groups to gather at different places or walk around the forest.

March
Gradually, winter herds of bisons divide into smaller groups and look for natural food. Unfortunately, it is hard to find this kind of food so they return to the previous places with prepared food. When the days are warmer, bisons eat the bark of trees creating a threat to saplings growing near the places where bisons gather.

April
Only some of the bisons stay still near the feeding sites. Most of them move dividing into smaller groups of about 15 individuals. The smaller groups consist of bisons of different age and sex, from the very young to old ones. Number of bisons in a group changes often and it depends on many reasons influencing bisons’ life, such as birth, mixing with other members of herds, etc. Order in a herd is changeable. The leader of a herd of bisons is generally old cow leading a calf.

May
High spring. Period of procreation begins and lasts until July, although it happens that it prolongs even till October. Pregnant cow leaves the herd for a few days and gives birth to her calf. The pregnancy lasts for 9 months, usually a single calf is born, twins are rare cases. Female bisons are very caring mothers, they feed their babies for at least a year and they can be aggressive when strangers come closer to their babies. Bisons can run at 40 km/ hour on a short distance.

June
The forest is growing. Animals can easily find the necessary food. Flora of the lowest parts of the forest is the basic ingredient of bisons feed.
Bison is the least choosy animal living in Białowieża National Park but it can only exists in a forest which has plentiful supply of food in various seasons of the year. The period of procreation still lasts.

July
Summer. Young bisons are still being born but the adoration season is coming. Because of numerous insects, attacking the herd at that time, animals protect themselves in dense young forest and go out to look for food in the evenings or early in the mornings.

August
The adoration begins. Bulls appear in herds of cows and young stock. They adore selected females for 2-3 days to fertilize them. After that they change the herd to look for other cows having rut. Female bisons don’t moo but they give a typical sound called ‘wheezing’. Generally, there is no fighting among bisons. If it happens, only strong animals fight with each other and the weaker individuals give the fighting up.

September
The summer ends. Adoration still lasts. Bulls are more excited at that time and they can be even dangerous. The period of full sexuality among male bisons maintains for only 6 years, from the age of 6 to 12. Young and old bulls compete among themselves to participate in reproduction. Cows can give birth to their babies to the end of their life. Bulls live about 20 years and cows about 25 years.

October
Autumn begins. Bisons find food in the forest but they check their feeding sites more often and often. Some cows have rut, some give births but generally animals prepare for the difficult period of winter.

November
More and more bisons group themselves near the feeding sites to have an access to the food, consisting mainly of hay. Some individuals leave the forest to prey on cultivated areas doing damage to the field.

December
The winter begins. Most bisons stay near the feeding sites using prepared provisions. On the warmer days they try to find food themselves, mainly they look for bark of trees and sprouts. Prepared food in the feeding sites allows and helps bisons to survive winters.