Chapter 7:
Spatial Distribution of Territories
It is advisable first to consider data characterizing the territorial distributions of individuals relative to those of other tigers separately for males and females, since individual differences exist within each sex, successively comparing data for each winter season.š Only with the support of such an analysis is it possible to pass on to the next stage: visualization of the basic characteristics of the spatial structure of the population as a whole.š š
Male Tigers:
The Winter of 1970-1971:š During this season, observations of
tracks were conducted on one male: "Emperor", whose movements were followed
within a small area along the middle course of the Gornaya River northward
up to the upper reaches of Malyi Klyuch Stream [in the basin of the Orekhovka
River (cf., Fig. 6)].š We probably tracked
this same animal on the following sector: from Shirokii Stream (in the Malinovka
River basin) to the narrow side valleys of Evseev and Kazachkov Streams (both
in the basin of the Gornaya River).š Data were not obtained on interactions
between male tigers during the first winter of work in the long-term study
site.
The Winter of 1971-1972:š The movements of the "Emperor" tiger,
which were revealed by a long period of tracking, included a large area: from
the narrow side valleys of streams along the left banks of the Gornaya River
to mountain spurs on the right banks of the upper reaches of the Orekhovka
River (cf., Fig. 6).š With respect to
almost all of the area in question, contacts between the "Emperor" tiger and
other male tigers were never observed.š The footprints of a large tiger, possibly
a male neighbor, were found on March 13 along Petrov Stream (Yurta Stream)
and also on March 16 in the upper reaches of Pravyi Igristyi Stream.š The
extreme southern points in the travels of the "Emperor" tiger lay at precisely
these sites.š Therefore, it is possible to assume that boundary interactions
between individuals took place in this instance.š Here a neighboring male
tiger, after emerging from the south onto the left bank slopes of Petrov Stream,
encountered the footprints of the "Emperor" tiger, walked along the slope
in a closed looped path, and then moved off in a southerly direction.
The Winter of 1972-1973:š According to data collected during this
season, the "Emperor" tiger stayed primarily within the confines of the valley
of Pravyi Igristyi Stream (along its middle course) and the basin of Bystryi
Stream (a left tributary of the Orekhovka River), also along its middle course
(cf., Fig. 6). The routes of another
male, the "Lazy" tiger, repeatedly ran across a significant part of the area
in question (cf., Fig. 7).š The space
where their paths intersected or coincided, is approximately defined by the
following border lines: the valley of Bol'shoi Stream and its tributaries
in its lower course--the narrow side valleys of streams along the right banks
of the Gornaya River from Medvezhii Stream to Kammenyi Stream; northward,
both male tigers reached the middle course of Malyi Klyuch Stream.
Their routes were especially closely intertwined at the confluence of Bol'shoi
Stream and the Gornaya River, i.e., within the limits of the "core" area of
the territory of the "Emperor" tiger.š The "Lazy" tiger moved along the tracks
of the "Emperor" tiger on particular segments of his path: it was in precisely
this manner that he went from the upper reaches of Malyi Klyuch Stream up
to the valley of the Gornaya River, a distance of over 20 km, of which only
0.8 km lay outside of a track that had been laid down previously (by the
"Emperor" tiger).š Direct encounters between these individuals did not occur
during the period of time that was characterized by our tracking.š In one
location, the "Lazy" tiger walked along the footprints of the "Emperor" tiger
both there and back (i.e., he made a doubled path), as if he were
examining the path of the tiger that had preceded him.š Not far from here,
he used laying places made by the "Emperor" tiger for a long rest.
According to the data that we possess, the "Lazy" tiger did not visit
that part of the territory of the "Emperor" tiger that included the basins
of Bol'shoi and Bystryi Streams (along the left banks of the Orekhovka River).š
Furthermore, his travels extended in a southerly direction for tens of kilometers
beyond the travels of the "Emperor" tiger: he regularly traveled not only
along the valley of the Malinovka River, but also along the basins of its
left tributaries, the Komsomolka River and Valun Stream.
In addition to the two males that have already been mentioned, we noted
the tracks of still another large (male) tiger, which we named the "Powerful"
tiger, within the area that we had under observation (cf., Fig. 7).š He visited sites that lay in direct
contact with the extreme southern points of the travels of the "Emperor" tiger:
the basins of Zvuchnyi and Petrov Streams.š This animal's territory covered
mainly the upper part of the Malinovka River basin.š We did not observe any
direct contacts between the "Emperor" tiger and the "Powerful" tiger; their
routes did not intersect during this winter.
When the "Lazy" tiger, coming from the side nearest the territory of
the "Emperor" tiger, headed in the direction of the Malinovka River and encountered
the "Powerful" tiger in the valley of Petrov Stream, a fight took place between
them.š As far it is possible to judge from tracking data, the "Lazy" tiger
did not possess his own territory.š For this reason, it is all the more remarkable
that his fight with the "Powerful" tiger took place exactly in the zone of
contact between the territories of the latter tiger and the "Emperor" tiger.š
Apparently, the encounter between the two males was nevertheless similar in
nature to a boundary conflict.š Having discovered a stranger on his path,
the "Powerful" tiger immediately manifested the most extreme aggressiveness
toward him (it is necessary to take into account the fact that the "Miniature"
tigress, with which the "Powerful" tiger constantly remained in contact, remained
nearby during this period).
The encounter between the tigers took place along a mountain slope on
a track made by wild boar.š For a distance of 70 m, the "Powerful" tiger pressed
the "Lazy" tiger backward along the track, along the sides of which there
remained continuous impressions made by their torsos and tails.š Then, having
shoved the "Lazy" tiger onto a small sector of land that lacked trees, the
"Powerful" tiger knocked him down off the track.š Here a zone of whipped up,
bloody snow extended over a distance of 20 m; wisps of fur remained on the
bushes.š The mortally-wounded "Lazy" tiger crossed over a knotted fallen tree,
which was hidden by snow, but the "Powerful" tiger, which had prevailed over
his opponent, swung about and, approaching the top of this fallen tree, headed
back over his own tracks.
The "Lazy" tiger lay for a long time beyond the fallen tree, then he
raised himself up, emerged onto the boar track and moved along it following
the "Powerful" tiger, i.e., in the same direction as the "Lazy" tiger
had been moving up until the fight.š The entire track was drenched in blood
for the first tens of meters.š The animal lay down quite frequently, leaving
spots of blood behind him.š From the site of the fight, these rest sites followed
one after another over distances of 30, 15, 20, 70, 150, and 30 m.š The last
laying place was used for a long time and was especially heavily permeated
with blood.š From here, the tiger turned to the left and walked along the
right narrow side valley of Petrov Stream.š One hundred meters further on,
bloody laying sites (two in a row) again appeared along his path.š Then he
crossed a large right narrow side valley lying to the right of Petrov Stream,
and, on the side opposite this valley, he approached a Korean pine tree at
the base of which was located a den made by wild boar.š He perished at this
den site (Fig. 9), having walked a distance of about
a kilometer from the site of the fight.š He lived for 12 days after the fight,
a fact that was established by the impressions of his still-moving tail on
freshly fallen snow.š The entire upper sides of the front paws of the dead
tiger had deep, longitudinal wounds that had been inflicted by claws.š Large
bruises were later discovered on the muscles of the front part of his torso.š
The "Lazy" tiger weighed 192 kg, and he was 9-10 years old.
š
Figure 9.š The "Lazy" male tiger after his death from a fight with another
male tiger.
š
The winter of 1973-1974:š We have only occasional observations
for this season.š The tracks of the "Emperor" tiger were observed on November
22 on spurs between Bystryi Stream and its tributary, Srednii Stream (in the
basin of the Orekhovka River). š
* * *
The results of three years of winter observations allowed us to visualize with sufficient clarity the regularly-used territory of only one male, the "Emperor" tiger.š The tracking data are insufficient to allow us to be able to judge with certainty how the territory of this tiger correlates with the territories of other males living in the neighborhood.š One of the neighbors, the "Powerful" tiger, is known; his tracks lay mainly along the upper part of the basin of the Malinovka River.š But even in the case of this tiger, his territory was not contiguous with the territory of the "Emperor" tiger over a broad area.š A continuous and sufficiently extensive boundary line did not exist between them. The routes of the two males only approached each other closely at one site along the fringes of the system of travels of the "Emperor" tiger: this is the narrow interfluve between the Igristyi and Bol'shoi Streams (with their tributaries, Zvuchnyi and Petrov Streams).š The length of the zone of overlap between the territories did not exceed 10 kilometers, and the width of the zone of overlap did not exceed 1-2 km.š In this way, the territories of the two male tigers that we could individually recognize remained practically isolated from each other.
With regard to the third male, the "Lazy" tiger, which traveled widely
within the territories of both the "Emperor" tiger and also the "Powerful"
tiger, this animal, as we have already said, apparently did not possess stable
territorial bonds.š The pathological changes in the bones of his extremities
give a probable explanation of the reason why the "Lazy" could not take up
and keep his own individual territory.š Nomadism inevitably led to his death
in a fight with one of the territorial males, the "Powerful" tiger.
Tigresses:
The Winter Season of 1970-1971:š The travels of the "Empress"
tigress with the small tiger cubs were localized to a very limited area along
Bol'shoi and Malyi Streams.š During the period of observation, only once
did she visit the right bank of the Gornaya River and cross the divide between
this river and the Orekhovka River (cf., Fig. 8).š Another of the tigresses that was
discovered within the boundaries of our study area, the "Miniature" tigress,
lived along the left bank of the Gornaya River during this winter: we tracked
her footprints along Igristyi Stream, a tributary of the Gornaya River (cf.,
Fig. 7).š No interactions of any sort were
observed between the "Empress" tigress and the "Miniature" tigress; in essence,
they were not even immediate neighbors.š The territories where these individuals
mainly stayed did not have clearly-defined common borders.š Neither of the
tigresses walked along the valley of the Gornaya River, which lay between
their territories.š
The Winter of 1971-1972:š Even if we do not take into account
an occasional long-distance entry of the "Empress" tigress into the area
along the right bank of the Orekhovka River (Sobolikha Stream), it is possible
to consider that her territory has essentially been enlarged while retaining
its previous core area (cf., Fig. 8).š
Now her travels included almost the entire interfluve of the Orekhovka and
Gornaya Rivers near the confluence of these rivers.š No tracking of the "Miniature"
tigress took place during this season.
The Winter of 1972-1973:š The "Empress" tigress, which already had
a new litter (consisting of one cub), remained on a very small area between
Srednii and Bystryi Streams near their confluence (cf., Fig. 8).š The footprints of another female,
on which we did not conduct regular observations (the "Unknown" tigress),
were observed on November 1-2, 1972, in the upper reaches of Strel'tsov Stream
on the right bank of the Gornaya River.š Apparently, it was her tracks that
were discovered at the end of winter along Kolyuchii Stream, a tributary
of Srednii Stream.š This female had two first-year cubs.š It is difficult
to form a judgment about the territorial relationships between the "Unknown"
tigress and the "Empress" tigress, since the first of these tigresses entered
the field of view of the authors for only a short period of time.š At any
event, the territories of the two tigresses lay in close proximity to each
other during this winter and were very small.š
The "Miniature" tigress, as before, principally kept to the upper part
of the basin of the Malinovka River (cf., Fig. 7).š During this year she apparently had
two tiger cubs (a litter that drew the attention of the tiger catchers, who
caught tiger cubs that undoubtedly belonged to the "Miniature" tigress at
the end of December in a narrow side valley of one of the left tributaries
of the Malinovka River).š Having lost her cubs, she began to travel widely,
from the left bank tributaries of the Malinovka River up to Bol'shoi and
Igristyi Streams in the basin of the Gornaya River.š In March, we tracked
her movements across high mountain spurs, where she crossed an area of strongly
differentiated topography.š Nevertheless, the routes of the "Miniature" tigress
remained far to one side of the living sites of the "Empress" tigress and
the "Unknown" tigress, which had settled in close proximity to the "Empress"
tigress.
Thus, the two females, upon which we conducted regular observations over
the course of three winter seasons, lived completely isolated from each other.š
One issue remains unclear: were these individuals "acquainted" with each
other, since during our tracking not one case of contact between their routes
was observed.š Although remaining clearly isolated from each other, their
territories were nevertheless situated in the same neighborhood.š In contrast
to the "Miniature" tigress, the "Unknown" tigress, along with her cubs, stayed
for some time in the immediate vicinity of the place where the "Empress"
tigress lived during this same winter.
Judging from the data that we possess, the territorial relationships
between tigresses are established in their overall form in the same way as
those of the male tigers, except that the females are more flexible in this
regard.š The more adaptable ways of partitioning and utilizing their territories
that are characteristic of tigresses, obviously, stand in a direct connection
with the dynamic nature of the dimensions of their territories caused by
the dependence of territory size on the presence and age of the tiger cubs.
Interrelationships Between the Territories of Males and Females:
The Winter of 1970-1971:š The travel paths of the male "Emperor"
tiger and the "Empress" tigress lay in the region from Medvezhii and Kolonkovyi
Streams (in the basin of the Gornaya River) up to the upper reaches of Bol'shoi
Stream (in the basin of the Orekhovka River).š Using this path, the tigress
and her cubs came upon the remains of prey that had been killed by the male.š
Twenty-six percent of the movements of the family that were tracked during
this winter relate to travels on routes that were shared with the male.š
Furthermore, the footprints of the male were not observed during this season
on a significant part of the territory possessed by the tigress (the mountain
spurs between Bol'shoi and Malyi Streams near their confluence).
The Winter of 1971-1972:š The observations from this year revealed
much closer interactions between the two tigers that were already known to
us.š The routes of the "Emperor" tiger and the "Empress" tigress intersected
or were shared over a large part of the area where the latter animal lived.š
The routes of the male overlapped with all but a few of the sites that the
tigress had visited.š These sites were the valley of the Orekhovka River
between Khvoinyi and Bol'shoi Streams, the narrow side valleys of Semkin
Stream and Podgornaya Brook on the right bank of the Orekhovka River.š In
general, the routes of the male covered no less than 70% of the area that
the female had taken over as her territory.š The core areas of their territories
overlapped to a still greater degree.
More than a third of the distance walked during the tracking of the "Empress"
tigress relates to her movements together with the male or along a path where
she is following his tracks.š In the case of the male, the proportion of
the routes that are shared with the female is less, only 10%.š This is explained
by the fact that, beyond the limits of the areas where their routes are closely
intertwined, the male traveled more widely: to the south up to Igristyi and
Petrov Streams on the left bank of the Gornaya River.š When estrus began
in the "Empress" tigress, she traveled together with the male along the right
bank of the Orekhovka River in the basin of Sobolikha Stream.š Here, on a
poorly-defined spur between two narrow side valleys, which are oriented generally
from north to south, their "wedding" took place.š This entire spur was covered
by tracks and the shared paths of the two tigers.š We often encountered "scrapes",
urine marking, and paired laying places along the tracks.š On a nearby slope,
we found the remains of a wild boar, which had been killed by the female,
but which had been eaten jointly by both tigers.š In total, the animals spent
about 5 days in this area.
The Winter of 1972-1973:š During this season, the nature of the travels
of the male "Emperor" tiger changed little, but the mobility of the female
"Empress", which had a cub, decreased quite abruptly.š The small territory
where the "Empress" tigress had settled down was completely covered over
by the routes of the male.š These routes also stretched farther, up to Kolyuchii
Stream, where we discovered the tracks of another tigress with a litter,
the "Unknown" tigress, in April of 1973.š Thus, two tigresses lived within
the limits of the territory of the "Emperor" tiger during this winter.
The sections of the tracks of the "Miniature" tigress and "Powerful" tiger
that we followed allow us to assume that the territories of these individuals
also broadly overlapped each other.š The "Miniature" tigress, which had lost
her cubs in December, had apparently already paired with the "Powerful" tiger
in January.
The Winter of 1973-1974:š In November, 1973, the tracks of the
"Emperor" tiger and the "Empress" tigress were observed in the same place
where they had stayed together during the previous winter: on the interfluve
of Srednii and Bystryi Streams near their confluence.
* * *
As is clear from the information that we have examined, the territories
of males and females overlap extensively.š This overlap is expressed not
only in an attachment to one and the same territory.š Constant contacts are
kept up between individuals of opposite sex; they often use common trails
with which they also define the degree of overlap of the "cores" of their
territories.š Together with paths, and also "key points" on their travels,
there are also shelters, which are used at different times by the male and
the tigress or by the offspring.š The female and the young often feed on
the remains of prey killed by the male (there are also cases of the opposite
situation).š In particular instances of direct encounters between the male
tiger and a human, the behavior of the animal is clearly that of a protector
of the nearby offspring from a possible enemy (observations of A. G. Yudakov).š
These facts provide a basis for the conclusion that tigers are characterized
by stable family groups and by familial territoriality (Yudakov 1974).
The "skeleton" (or framework) of the family's territory is formed, above
all, by the travel routes of the male.š These routes serve as a sort of reference
network for the movements of the tigress.š It is significant that we often
succeeded in searching out the tracks of the tigress by following the tracks
of males.š The sites where tigresses stayed with their offspring, and even
more so, the places where they left the cubs, temporarily abandoning them,
changed over the course of a single winter; but these places were not located
outside the limits of the system of travels of the male.š The territory that
has been taken up by a given male can include the territory of not one, but
two tigresses (e.g., the "Emperor" tiger with both the "Empress" tigress
and the "Unknown" tigress).š Monogamous families or the union of a male with
two (possibly several) females, which are precisely localized on a distinct
territory, apparently also create the spatial structure of the Amur tiger
population.
š