Early denning behaviour and raising of pups after weaning in wolves

I would like to share our knowledge on the early denning behaviour and raising pups after weaning in wolves basing on the information that was gained in Belarus mostly in Naliboki Forest and Paazierre Forest.

The information is divided into two items: the first  item is early denning behaviour in wolves; and the second one is raising of pups after weaning.

Early denning behaviour in wolves

Here it is important to define that under the wolf breeders at the denning stage we mean one or several pregnant females with an adult male or sometimes several males. Additionally, it may be a non-pregnant female amongst the mentioned breeders. Mech & Boitani (2003) called such an extra individual at denning an ‘adoptee’. However, as the adoptees role and origin is still ambiguous and disputable, we avoid this term. We definitely know that besides of the breeding pair (i.e. a pregnant female and its male (perhaps, the father of the coming pups) there may be other allowable individuals, both relative or non-relative ones. We are certain that they help with foraging and protecting pups at the den. Hence, when we say ‘wolf breeders at the denning stage’, it means either a breeding pair or such a larger breeding group. Usually the breeders send the rest of the pack members (mostly yearlings) away.

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An interesting question to answer now is how far from the breeders this ‘non-breeder part’ of the pack stays. To our findings, it is quite rare that they stay in the proximity from the actual denning site, nevertheless, both situations were revealed in our experience. According to our information that is based on tracking, marking of pups and camera-trapping, usually this distance between breeders at denning and yearlings varied between 3 and 8 km.

The above-mentioned behavioural switch of breeding wolves for denning happens usually about 10-15 days before parturition.  The breeders start staying in a rather small area up to 20 km2, usually 8-12 km2only.  In this pre-denning period, the pregnant females begin staying a lot in the denning site chosen, walking less and less with shorter and shorter radius of   0.6-2.2 km. This time i.e. 10-15 days before parturition breeders begin to dig a lot. It looks different. It may be a small pit, deepened couch, enlarged entrances of badger sett or red fox-earth, self-made burrow or just some try to create a burrow like an entrance only etc.

The pregnant female prefers to walk slowly leaving wavy track trail like a dog. It is heavy due to the pregnancy. On soft substratum (sand or peat) heavily pregnant female leaves unusually deep footprints.

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Tracks of heavily pregnant female wolf

The tracks of male breeders demonstrate busy. In this pre-denning period as well as during denning male breeders never walks slowly on forest roads for more than several hundred meters, usually it runs.

On the other hand, during the wolf denning period yearling wolves stay on a small area (up to about 70 km2, usually 10-20 kmonly), too. Appeared alone they got shy and walk slowly, location and trajectory of their track trails are characterized by not much sense, looks like that of loitering individuals, they carry and leave stupid things such rubber boots and plastic bottles,  they collect and gnaw ungulate bones and antlers. All the above help a lot to distinguish tracks of breeding wolf pair from yearlings and other non-breeders.

Here it should be pointed out that parent wolves may carry such “stupid things” too while bringing them for their pups to play. Such a toy is bitten by small thin canines of small pups and lies about dens, while toys of yearlings are forgotten by the at roads usually. In Belarus at two-thirds of the inspected wolf denning sites there were found pup toys. About a half of them was small things of man-made origin, others were mammalian bones and antlers.

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Concerning wolf breeder marking behavior in pre-denning and denning periods; they mark their currently occupied territory, but mostly not a lot. In this context, marking covers both urinating and scratching. Being at denning, the male breeder renews several marking points (1–7, mostly two or three) that are mainly situated on the terrain roads not far away, but not nearby the denning area — usually about 2 km away. Only rarely we saw the parent wolf scratching close to the active denning area. So in general, there is a low rate of marking and a ‘hidden wolf life’ in the area of 1–2 km around the den, lasting at least a month after parturition. The exception is the female’s scats and its urinating, which is done within the denning area because all the time it has to guard and take care of pups of few days old. As to yearlings that stay alone, they do not mark or only rarely do some marking. In the wolf breeding period the packs without a litter tend to continue marking intensively and mark their own territory, i.e. the home range widely (much bigger area than a denning area).
Also, it is worthwhile to notice that 2–5 days before the parturition, it looks like the marking behavior of the breeding wolves suddenly nearly stops. While actually, the parent wolves continue some marking in a few spots.

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In Naliboki Forest and Paazierre Forest in Belarus, wolves use the following denning habitats: thickets with many uprooted trees, especially spruces; thickets in logging areas with a lot of tree remnants and timber left-off; abandoned peatory with peat mounds left-off; and small sand-dunes with young pines and small openings at the border with boggy habitats having dense ledum and bilberry shrubs.

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In Naliboki Forest there are large meadows on drained lands surrounded by dense forest habitats. Such a meadow may be used by wolves as a denning habitat, when the height of the grass stand is about 40 cm and taller. Within grassy openings pups may be placed either nearby the opening center or at its edge at the border with the forest. Closely located terrain roads are not avoided by such families, if the grass thicket is sheltered enough. In grassy openings wolf parents evidently prefer to place pups at drainage canals, if they are present there. Sometimes, there wolf parents dig burrows preferably in canal banks or on relatively higher plots with a sand layer. The evident benefit of such a denning habitat is as follows: rather low abundance of mosquitoes, easy watching of surroundings, well-sheltered environments for pups and quite often for parents as well. During too rainy weather, pups may be temporarily replaced to the neighboring forest or they stay in burrows. If nobody disturbs the wolf family, they may stay in such large meadows until mid-October.

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Usually wolves locate their den not far away from the main road in the area that they have chosen for breeding. Parent wolves need to know what people do in the area by monitoring human-related situations from the den or not far from the den. On the other hand, it is convenient for parent wolves to walk by the road, when they go for hunting and come back with food. Marking of borders of the denning area at the road seems to be also important for the parent wolves, and on such a road it can be done faster in this very busy time. Moreover, just along such a road alien wolves may come into the denning area. So, such terrain roads are very essential for wolves at breeding. Nevertheless, that does not mean that wolves like breeding close to a busy road. Such a road nearby the denning area may be quite small and rarely used by people, but anyway at the same time it is still the main road, which humans use to get to the wild area. Really big roads with intensive traffic and their adjoining areas are normally avoided by wolves (however, not always, we recorded once pups staying 7–10 days in the pipe under a busy road). In most cases, wolves choose a rather calm terrain road (approximately up to 60 visits per day) by which people come into the area. Having a lot of data on wolf denning in Belarus, we learnt that in most cases (76%) a wolf den was situated on the distance of 0.4–1.0 km from the main road in the terrain fragment that was chosen by breeding wolves for denning. Moreover, in many cases the denning area was situated on the distance of only 0.4–0.7 km from the main terrain road.

There is the wide-spread belief that wolf pups should be located at a stream or another source of drinking water. Actually, it is hard to reveal such a relation in our data on the wolf denning. In Belarus and adjoining regions, there are 0.4–0.7 km of water courses per one km2 on average. Moreover, in the areas, where draining was conducted, the stream density is several fold (locally more than tenfold) higher than it used to be. Additionally, usually there are numbers of other sources of drinking water. Thus, there is so much water for wolves to drink that the mentioned feature of plausible den location is not useful, because water is actually available everywhere. The only exception are extensive sand dune areas with pine stands, where wolves breed rarely inside, but not rarely at the border. In a sand dune massif, breeding wolves indeed create dens not far from a stream or glacial lake, but it does not mean that such a den is situated one or two hundred meters from the water source. Parent wolves evidently avoid to situate pups in the close proximity of any waterbodies, because the surrounding is usually full of wild ungulates and people frequently visit these places. Both wild ungulates and people are dangerous for pups, and parent wolves know that very well.

While analyzing the ecological situation in the denning sites, we found that wolves prefer to situate their den in places where wild ungulates are not very active. These animals are a real danger for small pups (see Chapter 6), and parent wolves know that very well. Usually wolves follow this tactic quite strictly. Nevertheless, there may be exceptions. Once we discovered an open den at the roots of uprooted huge oak among swamped logging area, and there were many wild ungulates. The den was placed so high that it was unreachable even for an elk.

Despite of the fact that wolves avoid places with many ungulates for denning, at the same time, places with rich a prey supply(beavers and/or wild ungulates) need to be located close, optimally on the distance of 1–2 km.

Usually, during denning the breeding wolves avoid the places were brown bear or lynx are present frequently, at least, for the majority of cases. However, there may be some exceptions. For instance, once in Naliboki Forest we faced with the location of a brown bear hibernation den in the same 2 km2 plot, where a couple of wolves placed their pups. This denning area was still used by the brown bear family until 25th of May, at least, whereas wolf pups were placed there since the last days of April till the mid-May. The distance between the centers of the denning area of the wolves and the brown bear family was about one km only. As to lynx presence, formulating general rules are quite complicated. When wolf pups and lynx kits are of early days, and both the mothers stay nearby the dens, the wolf den and lynx den may be very close. In one case we found that lynx kits were placed in a former wolf burrow on an island in a black alder swamp, and the distance between this lynx den and the nearest wolf denning site with two litters (a case of pack double breeding) was only about 500 meters. When pups and kits are older than 10 days and the mothers leave the litters alone for hunting, such a proximity of lynx den and wolf den is not characteristic.

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As to denning itself, we would like to state that usually there are wolf denning sites including many dens (in our experience, it was up to 79), whereas a single den can exist from several hours to several days after giving birth. Parents relocate their pups from one den to a newly created one all the time, especially when there are too many mosquitos or the weather is rainy. Moreover, parent wolves worry all the time, and plausibly this nervousness also pushes parents to move their pups. Otherwise, it is hard to explain the many displacements of the litter. Normally, the new den, to where the parents move the pups (that is motivated by the above reasons, but not because people scared the wolves), is situated fairly close to the previous den — from 3 m to 1.3 km, on average about 50 m (more often 10–30 m only). There are two basic types of wolf dens: an open couch-den and a burrow (see the various photos given). The burrow-dens of wolves is reasonable to divide on two subtypes as a cavity-den and burrow-den. A cavity-den has merely a denning chamber, whereas a passage from the entrance to the denning chamber is absent or almost absent. In the case of a couch-den, the smaller pups are, the deeper and narrower such a den is. Such a narrow couch-den for early days pups may be called a ‘pit-den’. So, again couch-dens may be divided into two subtypes of a pit-den and a couch-den. A deep pit-den of 25–40 cm in the diameter keeps the pups together, saving their warmth and prevents them from creeping around. Sometimes even in the beginning of their denning breeding wolves do not create such a pit-den, whereas they make a larger den (some kind of a couch) with scratched floor. It is approximately 60–100 cm long by 40–70 cm wide. Quite often breeding wolves create a burrow by enlarging a badger sett or red fox earth, or sometimes a beaver burrow. The ‘wolf part’ of such an enlarged burrow extends for up to 5.2 m and in case of a relatively long wolf burrow it ends by a chamber of 45–70 cm in diameter. The diameter of the wolf burrow passage is usually 30–40 cm. From the denning chamber of wolves, a markedly smaller initial passage goes up (i.e. from former badger sett or red fox earth), where pups can hide. In peat and sand, fairly often wolves dig entirely their own burrow, usually 1–3 m long with a chamber in it. All breeding wolves use open dens, but not all of them dig burrows. Some of them produce many burrows (30–50 burrows, in particular, if they stay in abandoned peatory), whereas others only dig some entrances in badger setts and burrows of red foxes. Both members of the breeding couple (i.e. the male and female) create dens. The digging activity of the breeding wolves begins 5–21 days before parturition, whereas in most cases it happens about ten days before that. So, finding a wolf burrow does not mean that there are already pups nearby. Small open dens in kind of small pits suggest either there are already pups or they will appear in a few days maximum. However, such a pit with a worn down look says about the presence of pups. Fairly often parent wolves do not use the created burrows in May and the first half of June. Only later in July–August, such burrows may be used a lot; in particular if it is either too rainy or too hot, or if there are too many mosquitoes. Sometimes in June–August, wolf litters stay for many days in and around badger setts with enlarged entrances.

Another important question is what the possible distance between neighboring denning areas with different litters. It makes sense to consider this parameter, if the neighboring packs overlap in their home ranges. Otherwise, in the conditions of a low population density in wolves, neighboring packs may be too remote from each other, and it means merely that the wolf number is too low, i.e. markedly lower than the potential level at the habitat carrying capacity. In our experience in Belarus, litters of actually neighboring packs were for 6–24, mean 16.7 km apart from each other. However, it may happen that in the neighboring pack there is no litter at all. One of the reasons for that may be that the dominant female is sterile. Another cause may be that the pregnant female was killed after the mating season, for instance in March, which frequently happens. On the other hand, there may be two or even three litters in one pack, for instance when the dominant male (the father) mated also with daughters. In this situation, the litters may be situated within a smaller distance of 0.4–4.2, mean 1.2 km apart.

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While investigating the effect of several external factors on the wolf denning behaviour, we found that the number of mosquitos, rainy weather and human presence drive the complexity of denning behaviour in wolves. Increasing in these factors leads to the higher number of dens that were used by parent  wolves. Besides, the disturbance by people (mostly indirect disturbance like logging activity) leads to more used denning plots  and longer distance between the denning plots.

One of the interesting behavioral features of breeding wolves is that parents deliberately abandoned some pups to die, while relocating the litter from one den to another one. During our long-term experience of searching for wolf pups, we discovered several times such abandoned pups on the recent den: one abandoned pup (n=5), two pups (n=2), and once there were four abandoned pups. In most cases, the abandoned pups were dead. In one case one pup was killed by one of the parents. For all these 8 cases of leaving some pups on the former den, the parent wolves still had other pups alive that were tended by them. Normally this deliberate left of a few pups to die happened, when the litter was large (consisted of more than 7 pups), perhaps, too large for the wolf breeders. We recorded this in 5 out of 6 cases, whereas in 2 cases the number of pups was unknown. So, perhaps, this strange behavior of parent wolves having many pups (e.g. 8-12) is motivated by their feeling of inability to raise so many of them.

There is suggested by Mech & Boitani (2003) that a young mother may abandon her litter, first of all, in case of a multiple breeding in the wolf pack. In our experience with wolf breeding we did not face with this feature. In the above-mentioned 8 cases of a deliberate abandoning a part of the pups by the parents, for 7 cases we know the mother’s age approximately: only one mother was young (two years old). The other six mothers were older than 3 years; two of them were killed by hunters later during the next winter, and we determined their ages precisely (4+ and 6+).

The above-mentioned cases of left pups without care to die relate to early days pups. This is a more or less common phenomenon for breeding wolves. However, even older wolf pups may be abandoned by their parents. In the mid and late summer of 2013 in Naliboki Forest we faced with that for several times. The stories were as follows. During the quite long period of 1999 till the spring 2013, the wolves lived in the conditions of a high density of medium-sized (and thus not risky) prey: roe deer – on average 398 inds per 100 km2; wild boars – on average 234 km2; and beavers – 847 inds per 100 km2. It seemed that they were ‘spoiled’, being able to only foraging these relatively easy-catching prey, and they almost did not hunt bigger (and thus more risky) elks and even red deer (Sidorovich, 2016). Perhaps, at that time the local wolf population in Naliboki Forest even lost good skills to hunt this bigger prey as an elk. During February-July of 2013, these medium-sized preys declined greatly. An extremely long-lasting and abnormally snowy end of winter in 2013 impacted the populations of the wild boar and roe deer dramatically. More than 80% of the wild boars and more than 90% of the roe deer died in March and April. Then in June and July most wild boars, which survived through the harsh early spring, died from a hard disease. The summer of 2013 was rainy and beavers were not so easily available to hunt as usually. In these conditions, the efficiency of foraging by parent wolves declined strongly and therefore they refused their litters even so their pups were already 2-4 months old. We guess that 7 out of 11 present litters were abandoned to die during that summer of 2013 in Naliboki Forest (Sidorovich, 2016).

However, we could only learn the stories of two such litters precisely. One of the litters, which in May consisted of 5 pups, was left to die in the beginning of August, when still there were 3 or 4 pups. These pups starved, but persisted 15-20 days (at least, 1-2 of them survived so long), then they died. Another wolf litter, in which initially there were 7 pups, was abandoned late August. The pups were already big enough to forage something small themselves, and they hunted small rodents on the large grassy opening, where they stayed. By the lucky chance, the late summer and early autumn of 2013 were characterized by a high abundance of voles of the genus Microtus on the grassy openings, and 3 pups survived themselves for long till the beginning of October, when they were accepted by their parents again. Nevertheless, the food shortage suppressed their growing, and even in March of 2014 they were rather small compared to a normal almost yearling wolf.

On the other hand, some parent wolves tend about already dead pups (even decayed ones), by carrying them from one den to another, together with alive pups. Such a behavior by parent wolves was recorded by us for three times. These three litters on the moment of their finding consisted of 5 alive pups and one dead pup, 7 alive pups and one dead pup (already bad smelling), and 3 alive pups and 4 dead pups.

Stealing pups by mothers from each other in a case of pack multiple breading is another pattern of unusual denning behavior in wolves. They steal not all the pups; usually only 1-3 pups are taken from another litter. In our research experience and the practice of three other wolf pup searchers (altogether about 160 wolf litters that were looked through) such a denning behavior was registered for six time. In the respective litters, we recorded normally developed pups of clearly different ages. These mixed litters consisted of 3 and 4 pups of distinctive ages; 4 and 1; 5 and 1; 3 and 2; 7 and 1; 5 and 4. So it is clear that in such a case the wolf litter consists of bigger and smaller pups. Sometimes, this size difference may be too big, and bigger pups suppress the smaller ones. Such a suppressed small pup dies somehow, finally being trampled in the den bedding materials. Twice we faced with such a case of dead pups in the mixed litters. In one of those wolf dens we found 2 small alive ones, one small dead pup and 4 markedly bigger pups; whereas in another case – 3 small alive, 2 small dead and 4 markedly bigger pups.

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Differently aged pups from one mixed litter in the case of multiple breeding in wolf pack

One of the common behavioral patterns of denning wolves is the persecution of red foxes. Particularly wolf breeders kill vixens at their denning earths. Usually one of them is digging the red fox earth, while the other one is lying in an ambuscade in a close proximity. This deep digging into the burrow disturbs the vixen greatly, and finally it tries to escape. The wolf waiting in ambuscade overtakes the escaping fox and kills it. Usually the vixen carcass remains 30-100 meters from the destroyed burrow. As to the badger and raccoon dog, killing of them during denning period at their dens similarly as in the case of the red fox is not so common.

One of the specific features of the wolf denning behavior is finding a new partner very fast, when one of the mates died (or was killed). We learnt this by several anecdotal stories, but four of them we know in a very detailed way and were partial evidences. These stories may be briefly told as follows.

Story 1. In early June, still a bit lactating female wolf was trampled by six caws in a grassland at a homestead in Naliboki Forest; the pups survived somehow, and locals from the homestead registered presence of wolf pups on the distance of 1-2 km away during the whole warm season (pup howling, footprints etc.); in early November just in that same place a wolf pack was killed; the pack consisted of three pups of the year (one of them was markedly bigger than the other two pups); two big males (one of them, perhaps, was the pups’ father) and one adult female (‘step-mother’). Perhaps, the step-mother appeared quite soon, otherwise so small pups could not survive. We think that it was a case of multiple breeding in the wolf pack, and the step-mother was the mother of another litter, because the killed pups were much distinctive in their sizes.

Story 2. In Paazierre Forest in the mid-June a big male bringing food for its mate with pups was killed at a pathway to the denning site; the mother was slightly wounded in the hind leg, and it begun crippling; in 5-7 days a new big male appeared with the crippling mother; in the early July this step-father was killed; the female was still crippling; it got the new mate within 10 days; in December all of them i.e. the pair of the mother and second step-father and 4 pups of the year were killed more or less in the same area.

Story 3. In the late May in Paazierre Forest a big male wolf and a lactating female wolf were killed; then in about 3 days several adult wolves walked there again; in the mid-August in the same place (wolf pathway) five wolves were killed; the killed wolves were an adult female and 4 normally developed pups of the year of greatly different sizes; the next night at the same pathway a big male wolf and a pup were killed again. Afterwards in 9 days an adult female and male wolves and three pups were observed in the place proximity again. We guess that it was a case of double breeding in the wolf pack with quite fast getting of a new mate, when the previous partner was killed.

Story 4. In Paazierre Forest in the early August two adult wolves with 5 pups of the year were observed; one big adult male and one pup were killed, while the others escaped; in 10-15 days the two adult wolves and 4 pups were seen, while walking more or less in the same area; in early December a pack of 6 wolves was eliminated there; there were 2 pups of the year, one adult female (perhaps, the mother), big male (step-father) and two more males that look like yearlings.

At the end of this item, we would like to conclude with the main results of the denning studies. Defining under the wolf breeders at the denning stage one or several pregnant females with an adult male or sometimes several males, our results suggest that for the most of the investigated situations during the denning periods breeders send away the rest members of the pack (mostly yearlings), at least, for two months. In this case yearlings stay on the distance of 3 to 8 km from the breeders.

Denning in wolves takes place in several denning sites (up to four) that are situated on the distance of 2 to 7 km from each other. In each denning site there are usually from 10 to 30 dens (mostly open couches and few burrows), between which pups are relocated by the parents. Usage of each den is not long and lasts from several hours up to 3 days mostly. The choice of the denning site is determined by sheltering features of habitats, presence of wild ungulates as few as possible, absence of aggressive lynxes, good habitats for foraging not far away and proximity of the main road in the area chosen for denning. The number of mosquitos, rainy weather and human presence drive the complexity of denning behavior in wolves. The increasing of these factors leads to higher number of dens that are used by parent wolves.

 

Raising of pups after weaning

After the busy period of denning, when early days pups mostly eat the mother milk, a new and markedly different situation in the wolf family starts. The pups need milk less and less and begin to consume some solid food, mostly meat brought by the parents in their stomachs. The pups become more and more mobile and that increases the mobility of the parents.

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At this situation some interesting questions need to be raised. At which age of the pups does the lactation start to decline? At which age do pups begin to eat solid food? At which age of pups does the weaning happens? We did not find any substantial publication related to the questions for wild-living wolves in the European forest zone.
Of course, there are many published articles on the questions in relation to wolves in captivity, but those may only suggest some hypotheses for the wild animals. So, these answers still need to be answered for wolves in the wild.

Of course, there are a lot of studies conducted on these questions in North America (Mech & Boitani, 2003 and references therein), but the American and European wolves are greatly different. They are like different species in many of their characteristics, particularly behavioral traits. Again, it may suggest something, first of all, to establish hypotheses to study on the questions in Eurasia.

How is it possible to investigate such complicated questions in the wild? Telemetry? We did radiotracking (both VHF and GPS GSM) on twelve predator species and know very well, what the method can, but also what it can not. We disagree, when researchers read too much from the telemetry signal sequences with some inspection in the wild. Perhaps, here in Europe, where wolves are so shy, it is possible mostly doing study on sporadically gained carcasses of recently killed adult wolves and pups in the respective seasonal period, by gathering data long-term, what we actually did.

Thus, we would like to conclude that these quite important questions of the wolf reproduction are still poorly known in the European forest zone. We gathered not a lot of data on the questions and mostly it is sporadic data. Anyway, nevertheless this something is worthwhile to describe.

We used two kinds of gathered data. First, for seven times in the period of the mid-May-June we faced with situations, when pups of known age (they were found by us at dens before) ate solid food, mostly meat brought by parents in their stomachs. Another source of information were the carcasses of wolf mothers (n=6) and pups (n=89), which were killed by hunters in the period of May till the mid-July. In half of these cases we knew more or less the age of the pups (e.g. before the pups were killed by a hunter we found the den with the pups of early days) .

These irregular data suggest that the duration and importance of the lactation depends on the food base. While comparing a few cases in the conditions of very rich and poor prey supply, the duration the of lactation by wolf mothers was almost double different: for pups of about 40 days old the mother’s milk was already not so important in the conditions of rich food base and the mother secreted milk only a little bit; but, when prey were scarce, pups of almost 70 days old were nursed and the mother was still strongly milk-secreting. The killed pups had meat in the stomach since the age of 20-25 days old, and the stomachs of pups of 40-60 days old rarely contained milk and were filled with meat.

With finishing the lactation phase, a wolf family starts moving markedly more i.e. more often and on longer distances each time. While adverting to this period in wolf families, researches frequently use the term of a ‘rendezvous site’ and distinguished this from a resting site (e.g. Theuerkauf et al., 2003). The authors defined ‘rendezvous sites’ as places, where young wolves stayed for several days and to which the adults returned regularly, and resting sites as places, where wolves rested once for an hour or longer. We evaluate these different definitions as too sophisticated, and avoid to use them. In our quite big dataset (44 wolf families were more or less followed during summer) we faced with the following. Sometimes, wolf parents left the pups shortly in a particular place, came back and picked the pups up. It is something negligible, and it does not mean that it should be named somehow with a particular term. Indeed, nobody terms a random place, where a wolf defecated once. We think that such a short stay of pups in a particular place means that something was wrong with the choice or the family was making a too long displacement. Other places, where parents leave their pups, were used longer and in such a place parents spend much time (hours) every day. Fairly often parents rest few hundred meters away from this pup locations, controlling the situation around the litter and avoiding disturbance from too active pups. Well trampled resting couches of parents indicated this habit many times. So, both rendezvous and resting sites occur altogether, and we assume that it is quite reasonable. We call such a place the wolf family homesite or just homesite.

In July-September we found the wolf family homesites (n=135) in the following habitats or microhabitats:
(1) High grass stands with some bushes or without any bush usually on abandoned drained lands (mainly at drainage canals with wolf burrows in canal banks) – 18 (15) times, 13(11)%;
(2) Willow bush thickets – 7 times, 5%;
(3) Large treefalls – 15 times, 11%;
(4) Some treefalls in an old spruce forests – 24 times, 18%;
(5) Fern stands in young forests – 9 times, 7%;
(6) Wolf burrow sites, i.e. where several wolf burrows are situated in a small area up to 10 ha, it includes former badger setts with enlarged entrances; usually such wolf burrows were created in sheltered biotopes (quite often that was in abandoned peatories) – 19 (11) times, 14(8)%;
(7) Logging areas with a lot of tree remnants and early reforestation – 23 times, 17%;
(8) Rye fields – 2 times, 1%;
(9) Big haystacks (in that single case the big (about 30 meters long and 7 meters wide) haystack from the last year that was situated at the forest edge) – one time, 1%;
(10) Thickets of grass and dead tree material in abandoned beaver settlements; there were many beaver burrows in such places – 17 times, 13%.

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Taking into account possible factors and wolf demands for a family homesite, we noticed that all of them were well sheltered somehow. When there were plenty of mosquitos, the homesites of 1, 6, 8, 9 and 10 were mainly used by wolf families. During rainy weather the homesites of 3, 4, 6 and 10 were used more frequently. In the pup raising period after the weaning phase, the distance from the wolf family homesite to the nearest road and the frequency of wild ungulate presence in the homesite were not important in contrast to the denning period. As to presence of people (e.g. collectors of mushrooms or berries), we noticed that the influence was a particular family-related, because we found so different patterns of homesite location in relation to human disturbance. Once, parents immediately reacted on our visiting of their homesite by escaping with pups during the first night, whereas the others persistently stayed in the same well-sheltered homesite despite of the repeated visits of us and mushroom collectors. Actually, the first pattern of such a response was usual, while the second one was registered for three times only. In two situations there were young spruce thickets with some fallen trees and several wolf burrows, and in one case it was an extended treefall.

It is interesting to know how long a wolf family may stay in a given homesite. Checking that with howling, we are sure that it may be quite long. In one case, the wolf family stayed in a few hectares plot within tall grass stands at drainage canals for two months, at least. Another similar case, but this time in the mosaic of grass stands and willow bush thickets at drainage canals, the wolf family stayed about 40 days. Another long stay of a wolf family was detected in an extended treefall (five neighboring treefalls in the area of about 40 hectares), where the family lived from the denning in the late April till the end of September, i.e. five months. However, usually (more than for half of the cases) wolf families used homesites for 5-10 days only.

We analyzed pup diet compared to their parents diet in the period from mid-July till mid-September. We could not collect scats of pups earlier than from the mid-July onwards, even when we knew the particular place of their stay. In June and quite often till the mid-July the majority, (sometimes all) scats of pups are collected by their mother, and perhaps by both parents. Parents carry the pup scats in their stomachs (like in a bag) away, where they drop all of them by vomiting. We occasionally learnt this in Paazierre Forest in the late June of 2003, when a mother wolf was killed by a hunter from a hide in the proximity of the den. There were pup’s excrements in its stomach. We immediately realized that was the reason, why we could only find some scats at the wolf homesite with pups. Later in Naliboki Forest, we discovered wolf vomiting twice with many scats of pups, and we easily recognized it.

Such comparative dietary studies were carried out for 13 litters and their parents in 2004-2012 in Naliboki Forest in the localities of Hala Balota, Kupalishcha, Shubin, Kaliuhi, Sviaty Kalodziezh. It should be noticed that in those years, food base for wolves in Naliboki Forest was very rich. Looking at the data, the most distinctive feature of the pup diet is the markedly higher portion of beavers compared to that in the parents diet – in 1.2-2.9, mean 1.9 fold. Also, pups ate quite a lot small rodents, catching them themselves. Therefore, the small rodent portion in the pup diet was essential for 6 out of 13 litters studied.

Approximately, in the beginning of October pups start walking with their parents most of the time, however, still may be left for some time in a sheltered place. Since late October or early November pups follow their parents all the time.

 

 

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