Co-author Irina Rotenko
This year we studied the question of wolf reproduction in Naliboki Forest in the area of about one thousand square kilometres. In the spring of 2022, there were present two breeding groups of wolves in the study area: a couple and an adult male with two pregnant females. All five adult wolves were recognisable, and we knew them from the previous years.
First about reproduction of the three breeding wolves. In the late March one of the females gave birth in a burrow-den. In the 20th of April there were at least three pups with her (we saw them at the burrow entrance). Another female gave birth in the late April on the distance around 1.8 km from the den of the first female, and in the mid-May she had 4 pups of about 3 weeks old in her burrow-den, which we investigated. The father wolf served for both breeding females. They visited denning area and dens of each other. All the three wolves were numerically registered walking together in April and May.
Plausibly the litter of the first female was extirpated by lynx adult male, which was registered visiting the burrow-den with pups. After this visit of the lynx, the mother wolf was not registered with her pups anymore.
In the below footage you will see preparing of several dens by pregnant female wolf and four pups of the three breeding wolves. A total, at least 34 such prepared dens in kinds of either a burrow or a cavity or only a pit there were found in the denning area of these three breeders. You see the four pups in an outlier of badgers that was enlarged by the breeding wolves. The litter was inside this burrow 4-6 days.
In the early June there were alive only two out of the four pups (see video below), which you may see with the mother at another burrow-den. In November only one of the four pups was still alive.
Concerning the breeding couple of wolves, they were very early breeders. The female gave birth approximately in early March or even in the late February. The couple den was hidden in drainage canal bank that was covered by dense reed stand in the centre of a huge meadow. In the late May the wolf family stayed within forest habitats in a treefall. There were four surprisingly big pups. Only one of them was alive in the beginning of November.
So, in our material on wolf reproduction in Naliboki Forest in 2022 (three litters were investigated) the mortality of pups till November was following: (1) 100%; (2) 75%; (3) at least 75%.
Zoology by Vadim Sidorovich 
interesting that one pair bred so early , I wonder if this is down to the changing Winter weather patterns I have noticed in recent years in Belarus, informative post , thank you for sharing
As lynx, wolves like also walk on the trunk of fallen trees, how to explain the small number of pups in each pair ?
Dear Jean-Claude, yes, wolves and even pups sometimes walk on fallen tree trunks, but that happens not so often as in lynxes, and young wolves are not able to climb trees and to be safe there as lynx kittens do. Additionally, walking by wolves on fallen tree trunks happens on a rather small height as 0.5-1.5 meters.
Hello Mr. Sidorovich, I would like to ask a question about mange. do wolves in the Naliboki forest suffer from mange more often? and what about other animals? And I remember the wolf that was filmed fighting with the lynx Kazimir, it looked like it had a very thin tail and very little hair and messy fur, does it look like it has mange? I have this question because I have seen a video of a wolf suffering from mange in Italy and it might look a bit like this one. Thank you and I am very much looking forward to your reply.
Thanks for the question. Yes, some years the mange disease is a real problem for canids in Naliboki Forest. In 2013-2015 there was the last outbreak of mange here, but every year a canid with mange may be registered.
Interesting article, thanks for sharing. Still problems of high mortality pups in Naliboki forest.
Thank you for your work. How do you explain this very high mortality rate? lynx predation? poaching? others ?
Thanks for the question. Actually, I have numerically analysed why. Please, see in the special chapter of the book (Sidorovich & Rotenko, 2019) ” Reproduction biology in grey wolves……..” – free to download in the Research Gate. Also, see the several special posts in the research blog.
Very interesting book. I recommend to all fans. It solves many doubts and perplexities about the life of wolves. Thanks so much for sharing.
Thank you. Roger MATHIEU