Distribution patterns and habitat combinations inhabited by lynx in Belarus

Planning to write a book about the lynx in Belarus, we first of all aimed to investigate aspects of the species’ population ecology which were insufficiently studied across its range. At the same time, we want to present the main regional characters of lynx ecology in the main types of habitat combinations related to soil, climate and relief: diet and distribution patterns.

We consider only three main types of habitat combinations that are mostly by lynxes in Belarus. All three types are forested landscapes. In Belarus lynxes avoid large openings without or with few woody cover. We assume that such a preference for forest biotopes in lynxes has its origins in the strong interference with wolves. On open terrain lynxes are vulnerable to attacks of wolf packs, whereas in forested terrain lynxes can easily escape from wolves by climbing in trees, or use trees during a fight with a wolf. Forests are not only safer for lynxes, it gives them such an advantage that adult lynxes can even kill adult wolves that are walking alone.

The first habitat combination, which may be inhabited by a local lynx population, is mixed forest that consists of coniferous (spruce, pine) and small-leaved deciduous trees (mostly aspen, birch spp. and alder spp.) on richer or poorer soils (high or low clay content). This near-boreal type of forest habitat combination is widely spread in the northern part and in most of the central part of Belarus. In these regions eolic sand dune massifs with homogenous pine stands are usually less than 400 km² in size: not vast enough to support a local lynx population independent of the surrounding richer habitats.  These poor habitats are only rarely inhabited by lynxes, only in places of capercaillie concentrations (overwintering places, leks and nesting areas).

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The second forest habitat combination, which may be inhabited by a local lynx population, is similar to the first one, but it is ecologically richer with a more nemoral character. This forest habitat combination is again a mixed forest that consists of coniferous and deciduous trees on richer or poorer soils with higher or lower clay content. The difference between the first and second forest habitat combinations is that in the second one the forest floor is richer and the forests also contain broad-leaved deciduous trees (lime, oak, maple, ash), resulting in a higher biomass of seed crop.

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These features and milder winter conditions result in higher habitat carrying capacity for lynxes with richer food base and easier survival during winter, particularly for subadults. This more nemoral type of forest is widely spread in a part of central Belarus (particularly central west) and in a part of southern Belarus (northwards of the Prypiats’ valley). Again, as in the first type, sand dune massifs with homogenous pine stands are usually less than 400 km² in size: not vast enough to support a local lynx population independent of the surrounding richer habitats.

A local lynx population can be defined as a territory-neighboring group of lynxes of minimally 12-15 individuals. Within 12-15 lynxes there are, at least, 3 sexually matured females. Such a territory-neighboring group of lynxes is more or less stable during mating season. When there are less than 12-15 lynxes, being a polygamous species, adult males tend to spread widely during mating season in search of mates. The next years, having no or shortage  of adult males, breeding females tend to spread far away as well, and such a territory-neighboring  group of lynxes gradually disappears. In the case of a minimal local population in the first and second types of lynx habitat combinations, lynxes live in proximity of each other. At the same time, other areas with very similar habitat carrying capacity can be unpopulated by lynxes, creating a patchwork in the spatial structure of the whole unsaturated lynx population.

The third forest habitat combination which may be inhabited by a local lynx population in Belarus, is situated southwards of the Prypiats’ valley. It is a vast mosaic of pine forest, deciduous forest, grassy marshlands and hypereutrophic bogs on very poor sand or peat soils. There pine stands on sand or boggy soils largely prevail and there are pine stand massifs of about 400 km2 and much larger. This forest massif southwards of the Prypiats’ valley is populated by lynxes, but with a low density due to the low habitat carrying capacity. The ecologically rich Prypiats’ valley is mostly unpopulated by lynxes because of the large and long-lasting spring flood. Results from several research expeditions undertaken to this area indicate that lynxes are not able to populate this area with a density higher than 2 individuals per 100 km² because of the low food base (actual and potential). Perhaps, this indicates another pattern of distribution in lynxes. A patchy distribution with individuals living in a close proximity, which was defined above for the other two lynx-related habitat combinations, seems impossible in this continuous, almost barren terrain, where lynxes need to roam widely to supply in their food demands.

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As it was described above we consider three main types of habitat combinations (hereafter called ‘environments’) inhabited by lynx in Belarus. We wanted to investigate the main ecological characters (distribution pattern, habitat use and diet) of the lynx populations in all three environments.

We finished these studies in the first environment (Paazierrie Forest; Sidorovich, 2011) and are finishing in the second environment (Naliboki Forest, Sidorovich, 2016). However we still have insufficient knowledge about lynxes in the third environment: the Paliessie region in southern Belarus.

From the late 1980’s till 2014 eleven expeditions were  undertaken in the region. The fieldwork during these expeditions was mostly targeted on otter and European mink. It was also part of the studies on vertebrate predator-prey relations. Only three expeditions focused specifically on lynxes and wolves. In August and September 2017 we carried out two more short but specific lynx expeditions in the region.

So far we learned that the local lynx population is characterized by a low density: in 2008-2014 about 0.4-1 lynxes/100 km²; in 2017 about 0.1-0.3 lynxes/100 km² (one lynx in the inspected area of 700 km²). Perhaps, this indicates a local distribution pattern different from that in the first and second environments. A patchy distribution pattern seems impossible in this continuous, almost barren terrain where lynxes need to roam wide to supply in their food demands.

32 scats were analysed between 2008 and 2014. Frequency of occurrence of undigested prey remains: hares 14, roe deer 13,  beaver 8, and 13 of diverse other prey (1 wild boar, 1 red fox, 2 red squirrel, 9 rodents).

In 2017 we only found 5 scats containing the remains of hares in four and one with beaver remains. Here it is worthwhile to mention that in 2017 roe deer was not found at all in the inspected 700 km².

In 2018 and 2019 we are going to undertake several more lynx-targeted expeditions to learn more.