Posted on 08 July 2020
The first new bison calf of 2020 has been spotted by rangers at Bison Hillock.
Large numbers of free roaming bison in the Southern Carpathians sculpt the environment and maintain the necessary and fragile balance so important for biodiversity, and for the well-being of us all. The success of a rewilding programme depends on many factors, but one of the key ones is new life being born in the wild. At least 20 bison calves have been born in the wild in the Southern Carpathians since the beginning of Rewilding Europe and WWF-Romania
’s rewilding initiative in 2014.
The wildlings of Bison Hillock
In addition to the calve just spotted, this spring, Life Bison rangers have identified about 8 baby bison born last year in the Țarcu Mountains. 8+ calves is the highest number yet to be seen in the Bison Hillock and we hope this year we will see even more claves being born and surviving to become the strong adults.
“There could be more calves. Counting them is not easy as they quickly disappear in the forest under the watchful gaze of the protective group that keeps them hidden behind massive bodies
.” says ranger Daniel Hurduzeu.
The calves are still too young and too far away to determine their age or gender. Since suckling calves are a rare sight, rangers cannot be sure which calf belongs to which female. Mothers are always on the watch and alert, and a group will move on when it catches a scent of human presence.
The main threats to the calves are old bulls which can, in their quarrels, trample the little ones. Young males can easily lose battles with experienced bulls. Stray dogs from nearby villages or sheepdogs from nearby sheepfolds can also chase and injure calves if they can get them separated from the bison herd. Weak calves can be attacked by bears or wolves.
A danger for all bison is overgrazing, especially with cattle. Cattle can change the composition of meadows or grasslands, leaving plants less valuable for biodiversity and less nutritious for bison. The change in diet can affect a bison mother’s milk and the diet of the entire herd. Poaching of other species can also disturb the environment, and thus the balance essential for the development of new generations of bison.
Birth and growth
Bison calves are usually born between May and July, giving them enough time to become strong and ready before winter. However, there are exceptions when females give birth in winter. Pregnancy lasts about nine months.
On average, male calves weigh approximately 27 kg at birth, and females around 24 kg. The calves have reddish fur at birth, but after a few months, the fur begins to change to chocolate- brown and they start to moult like adults. The colour and density of bison fur varies with the season. After six months, a calf can weigh about 100 kg. While females experience a greater increase in body mass in their first year, their growth rate is comparatively slower than that of males by the age of 3–5. At maturity, female bison can reach over 500 kg while males are known to surpass 800 kg. Bulls reach sexual maturity at the age of two, while cows do so in their third year.
First steps in the wild
Female bison leave the herd to give birth in a quiet and safe place in order to make sure the baby is safe from the huge adult bison and other threats. A bison calf follows its mother closely, especially in the first week after birth. Cows that have given birth are very caring and alert. When bison calves are slightly older they show playful behaviour and grow up together in the herd. Calves suckle for several months; however they also start eating vegetation within a few weeks.
Power in numbers
Mixed groups consist of adult females, calves, young aged 2–3 years, and young adult bulls. The animals have really adapted to the wild and are more cautious than they would have ever been in a reserve or breeding centre. The mothers will teach these behaviours to their young - helping future generations thrive. The project is clearly on the right path.
, the largest land mammal in Europe, is a key species for preserving wilderness strongholds. The bison’s browsing ability in the search of food helps maintain a mosaic of forested areas and grasslands, a landscape which is highly valuable from for its biodiversity and natural resilience in the face of climate challenges. Moreover, the bison is a species that, if successfully re-introduced and its habitat actively preserved across the entire Carpathian Mountains, will help maintain ecological corridors on a large scale, allowing for species migration, be it the bison itself or other large carnivores such as the brown bear, the wolf or lynx. The European bison is one of the most threatened large mammals in the world, and it is protected at the European level. WWF Central and Eastern Europe
’s and Rewilding Europe
’s Life Bison Project
aims to establish a wild bison population that is demographically and genetically viable, by reintroducing 100 individuals in south-western Romania, where one of the largest wilderness areas in Europe survives. The rewilding initiative is having a beneficial impact on the landscape and people.
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