Coauthor Irina Rotenko
Recently in Naliboki Forest in the central-western part of Belarus we registered when heavily pregnant female lynx was inspecting the last year burrow-den of wolves plausibly as one of potential sites for her denning.
The question of denning by lynxes we continue to investigate together with Wild Naliboki team, Belgium and Maximilian Hetzer, Germany in Naliboki Forest, the central-western Belarus (Sidorovich et al., 2018).
Before (Sidorovich et al., 2018) there were several our findings on the question, which suggest strongly that female Eurasian lynxes used burrows for denning and raising of small kittens not rarely. We will mention those cases once more in the below. At the same time, our materials on the question that we have got nowadays evidence that burrows are only one of the several types of lynx lairs in Belarus.
The previous materials on the question of lynx denning in burrows is as follow. From 1997 until 2017: long stay (several weeks) of lynx kittens in abandoned badger setts was registered for eight times in late June-July by track inspection. Of course, we cannot rule out that the mothers brought the kittens into the setts after parturition, but we believe it is likely that they were born in the setts and started to appear at the entrances when they were a month old. Remarkably, in Russia, one of the three lynx dens that were discovered by lynx researchers in non-rocky regions was a lair with small kittens in an abandoned badger sett (Matyushkin and Vaisfeld, 2003).
7 May 2003: a recently used lynx den was found in a beaver burrow.
July-August 2016: a lynx mother was photographed with her kittens at a comprehensive burrow network of a former beaver settlement on canals with sandy bank sides with a lot of footprints of the kittens that went into the burrows.
May 2014: a female lynx equipped with a VHF-radiocollar gave birth in an abandoned peatery at the edge with dry forest. Despite inspection of the spot, the kittens were not seen, however, there were three possibilities where the kittens could have been: an abandoned badger sett with two entrances enlarged by wolves (the entrances were clearly used but no clear lynx tracks were found), quite wet beaver burrows and semi-collapsed wolf burrows in peat mounds.
14 May 2017: tracks of 2-3 weeks old kittens were found inside an abandoned beaver burrow, in a canal bank in spruce forest. Later in summer, the lynx family stayed in a spruce tree fall.
May 2015: the raising of kittens at a former wolf burrow, registered by camera trapping. We are not sure if parturition took place inside the burrow.
April 2016 and 2017: camera trapping revealed that pregnant female lynxes visited the same former wolf burrow as in 2015, but finally they did not use it, perhaps, because pregnant female wolves were interested in the burrow, as well. In early July 2017, a lynx mother stayed in this former wolf burrow with her kittens for at least a week.
May-June 2017: a pregnant female was photographed by camera traps on the 13th of May. In late May or early June, the lynx family (mother with small kittens) stayed at a former wolf den (type ‘couch-den’), at the base of a fallen spruce, surrounded by a dense spruce thicket. On a distance of 60 meters, there was a wolf burrow that was visited by the lynx family as well.
Early July 2017: a lynx family stayed in a self-made, shallow burrow in sandy soil, under a root plate of an uprooted tree on a clearcut with many tree remains and early reforestation.
July 2018: mother lynx situated small kittens (about two months old) in badger sett for few days.
Additionally one of our respondents discovered small lynx kittens in inactive badger sett. The kittens were still blind, and the entrance was enlarged by wolves several years ago.