Chapter 6:
Characteristics of the Tigers' Movements. Size and Structure of Their Territories
In order to analyze tigers' use of their territories, it is necessary
above all to examine in detail the patterns of travel by individual animals
as revealed by tracking. The complexity of the problem of the structure
and boundaries of territories in large predatory mammals (as well as the
frequent attempts to solve this problem based on a precarious empirical foundation
or based solely upon theory) creates the need for maximally complete disclosure
of factual information. The data from our tracking of male tigers and tigresses
are examined below for each individual in succession.
Male Tigers:
1. The "Emperor" Tiger. The tiger designated by this hypothetical
name had a width of the callused sole pad (or "heel") of the front paw of
10.5 cm. He could be characterized with the following individual behavioral
feature: his "scrapes" were always made to the left side of his walking
path.
The Winter Season of 1970-1971: The travels of this tiger
along the middle course of the Gornaya River and in the region of the divide
between this river and the basin of the Orekhovka River (which lies to
the north) were revealed by means of tracking during the second half of
February-beginning of March of 1971 (Fig. 6).
The animal's path lay at first along the right bank of the Gornaya
River to the westward. Then, with the appearance of mountain spurs, his
path ran to the north and northwest along its tributary, Kolonkovyi Stream.
The animal surmounted the divide, which lies at an elevation here of approximately
600 m above sea level, and descended into the upper reaches of Bol'shoi
Stream (in the basin of the Orekhovka River). Here, after a long stop (with
prey), which was accompanied by a closed looped path (near the kill site),
the tiger's direction of movement changed to the opposite direction: the
animal turned and started back into the basin of the Gornaya River. Here,
he practically repeated his former route, although he almost never walked
over his old tracks.
Figure 6. Schematic map of the movements that we tracked during the
winter seasons of 1970-1973 for the male tiger designated as "Emperor".
1) 1970-1971; 2) 1971-1972; 3) 1972-1973
Having reached the mouth of Kolonkovyi Stream, the tiger moved
along the valley of the Gornaya River in a westerly direction. After walking
a distance of 10.3 km, the tiger once again turned toward north, following
the course of the valley of another right tributary of the Gornaya River:
Kamennyi Stream. Having begun on a path along the mountain slopes of the
left bank of this stream, the tiger descended farther into a valley very
close to its bifurcation. From here, the tiger passed, still going somewhat
toward the north, along a mountain spur, where, shortly after, he abruptly
changed his direction. Walking along the valley of Kamennyi Stream and the
adjacent slopes, the animal once again emerged into the valley of the Gornaya
River at almost exactly the same place where he had begun his route to the
north. Having crossed the valley of the Gornaya River, the tiger moved
toward the southwest, keeping to the slopes of the left bank of Mit'kin Stream,
a left tributary of the river. Tracking was discontinued here.
Summing up, the tracked path of this tiger totaled 79.2 km for the observation
period from February 14 to March 13, 1971. On the map, the travels of this
tiger are depicted as a horseshoe-shaped figure, the basis of which is
formed by the path of the animal along the valley of the Gornaya River.
The "branches" of this horseshoe are oriented in the following directions:
one toward the northwest (9 km in length), and the other toward the north
(with a length of 4.5 km). Changes in the general direction of his movement
that were nearly equal to 90o were observed in two instances near
the convergence of valleys of the tributaries with the valley of the main
river. Turns of close to 180o were observed in the upper courses
of small brooks. The tiger's lines of movement along the valleys of the
Gornaya River and Kamennyi Stream were nearly straight or else were slightly
meandering. The routes near the divide between the two rivers, in contrast,
were distinguished by a significant tendency to meander. It is precisely
along this sector that the path of the male tiger partially coincided with
the travels of a family (a tigress and two cubs).
The initial and final points of the path that we tracked are located
on the right and left slopes of the valley of the Gornaya River and lie
at a distance from each other of 12.5 km (as measured along a straight line).
The tiger moved principally along the lengths of mountain spurs and valleys.
Twice, he surmounted the divide of the main (i.e., of those on the
study site) river basins. He successfully crossed two mountain spurs on
two occasions. This tiger crossed the large valley of the Gornaya River,
and he crossed 16 valleys of large and small streams. A return to a section
of the route that he had walked earlier was noted in one instance. Furthermore,
a crossing of the valley of Kolonkovyi Stream at one and the same place
was observed twice. Due to the lack of coincidence between the paths of
the tiger in a northerly direction and on the return route (these paths forming
the "branches" of the horseshoe), all the routes along Kolonkovyi Stream
across the ridge (and back) and also upward along Kamennyi Stream (and back)
may be considered in practice to be doubled. In not a single instance were
the lines of movement of the animal to the north and on its return route distant
from each other by more than a kilometer.
The Winter Season of 1971-1972: In November, the tracks of male
tiger "Emperor" were followed for a distance of 17 km in the basin of the
Orekhovka River (Fig. 6).
Making a smooth arc in his line of movement, the animal walked
across the upper reaches of Malyi Klyuch Stream and the mountain spurs dividing
the right tributaries of Bol'shoi Stream (which merges lower down in its
course with Malyi Klyuch Stream). Here the general direction of his movements
was from southwest to northeast. The tiger walked across a sector in the
upper reaches of Bol'shoi Stream that he had visited the previous winter.
Along the entire length of this sector, the male followed the tracks of
a tigress. A turn of nearly 90o was observed once, at the end
of the sector.
On December 1, tracking was continued at a significant distance from
the site of our previous encounter with this tiger: in the valley of the
lower course of Pravyi Igristyi Stream (in the basin of the Gornaya River).
The tiger walked upward for a distance of approximately 5 km along the valley
of the stream (i.e., to the southeast). Then he turned to the east
and crossed the interfluve of Pravyi Igristyi and Bol'shoi Streams in this
same direction. Following the course of the valley of Bol'shoi Stream,
the animal again moved toward the southeast. His path from Igristyi Stream
is drawn with a zigzag-shaped line with "curved" turns. The entire sector
that we followed added up to 26.2 km.
The study of the movements of this same
male tiger was continued after more than a month's interruption. Other observers
repeatedly noted passages of tigers through the basin of Malyi Klyuch Stream
during the course of January. The animals came from the side near Bystryi
Stream. Probably, the tracks of the "Emperor" tiger were also among the
tracks that were observed. It was precisely in the valley of the Malyi
Klyuch Stream, near its fork, that we also began to track his footprints
at the end of January. The tiger walked upstream along the slopes of the
right bank, then he went downward along the left bank. Abruptly turning
around, the tiger returned to the area near the fork of Malyi Klyuch Stream.
Thus, the tiger repeated a similarly oriented path along the middle course
of the stream on three occasions. On the whole, his route on the left bank
appears like an elongated loop. There was a long-term resting site (or laying
place) at the extreme northern point of this looped path. From the valley
of Malyi Klyuch Stream, the tiger at first moved toward the east and crossed
onto the slopes of the basin of Bol'shoi Stream. From here, he went toward
the south along the divide between Malyi Klyuch and Bol'shoi Streams. Continuing
in this same direction, he crossed into the basin of the Gornaya River.
In the upper reaches of Bogdanov Stream, he repeated a path that he had walked
the previous winter for a short section of his route (see above). From
the upper reaches of Bogdanov Stream, the tiger walked toward the east and
moved along the right bank of Kolonkovyi Stream. Tracking was discontinued
here. The entire route from the fork of Malyi Klyuch Stream comprised 31.8
km. This route began with a long looped path, and farther on continued
its general outline toward the southeast. On three occasions, the animal
made turns that were nearly 90o.
Tracking was continued at the beginning
of February (Feb. 4, 6, 8-12th). The following section of the animal's path,
which has a length of 66.9 km, begins on the right bank slopes of the Gornaya
River not far from the mouth of Kolonkovyi Stream. With a sharply convex
arched path (of length 17.3 km), the tiger walked along the left bank of
the Gornaya River and returned along the right bank in the neighborhood
of the mouth of Bogdanov Stream. Farther along Bogdanov Stream, the animal
turned toward the north. If the small section where a person disturbed the
tiger is not counted, the tiger's path from the valley of the Gornaya River
was oriented toward north without any significant deviations. By moving
in this way, partially repeating his route more than once, the animal crossed
into the basin of the Orekhovka River and descended to the upper reaches
of Bol'shoi Stream. Here, he once again walked across a site that he had
visited the previous winter. Farther on, the tiger moved toward the northeast,
crossing the right tributaries of Bol'shoi Stream and the mountain spurs
that separate them. Thus, he came out into the valley of Khvoinyi Stream,
a left tributary of the Orekhovka River.
With a smoothly meandering path, the animal, having crossed the
upper reaches of this stream and the slopes of the right bank of this stream,
once again went toward the north. Farther on, he crossed into the basin
of Bystryi Stream and turned to the east, where he continued his route in
the same direction. The complete route (from the Gornaya River) can be depicted
with a weakly arched line (the sole exceptions are the arc along the left
bank of the Gornaya River and the smooth zigzag in the upper reaches of
Khvoinyi Stream). Only in the second case did the tiger undertake turns
that almost equaled 90o. Several smoother turns, from a northerly
direction to a northeasterly direction, were observed during the tiger's
descent into the basin of Bystryi Stream.
Later (February 24), the tracks of male tiger "Emperor", walking now together with a tigress, were encountered along the upper reaches of Khvoinyi Stream. From here, moving principally in southwesterly and southerly directions, the tiger reached the valley of the Gornaya River, traversing a distance of 26.5 km. The male walked together with the tigress over a large portion of this route, with this section of the route differing by its slight curvature. After an interruption, we continued tracking in the basin of Malyi Klyuch Stream. The tiger descended into the valley of Malyi Klyuch Stream from the left shore in the middle part of its course. The tracks of this animal had also been observed here earlier. From here, the predominant direction of his movements became easterly; thus, he crossed the basins of Malyi Klyuch, Bol'shoi, and Khvoinyi Streams. From the ridge between the Bol'shoi and Khvoinyi Streams, the tiger again walked together with the tigress. The animals went along their own old track, which had been laid down in the opposite direction 7-9 days previously, across the mountain spur. From the upper reaches of Khvoinyi Stream, the tigers moved at first to the east, then afterward to the northeast. Having reached Bystryi Stream, they abruptly turned toward the north and soon after came out into the valley of the Orekhovka River. The entire route of the male tiger from the valley of Malyi Klyuch Stream to the river comprised 37.1 km.
Farther on, the animals crossed onto the right bank of the Orekhovka
River. The path of the male along the right bank resembled an irregularly
formed arc with a loop and doubled tracks in the most convex part of this
arc. Both the twinned path and the loop ran along a mountain spur between
Levaya and Pravaya Sobolikha Streams, where the pair of tigers stayed during
their "wedding". The male walked alone from the site of his return to the
left bank of the Orekhovka River. Here, he headed toward the southwest,
crossing the valleys of small left tributaries of the Orekhovka River. Farther
on, he crossed the basin of Bystryi Stream and reached Khvoinyi Stream.
On this sector, the tiger changed his direction of movement to one that was
the opposite of that when he traversed it together with the tigress, but
he went along a somewhat different route. From the upper reaches of Khvoinyi
Stream, he walked again mainly along a path that he had walked earlier. The
animal proceeded across the basin of Bol'shoi Stream and crossed over into
the basin of Bogdanov Stream, where he descended along its right bank slopes
to the Gornaya River.
He went in a southwesterly direction along the valley of the Gornaya
River and reached the mouth of Bol'shoi Stream, which is a left tributary
of the river. From here, the tiger abruptly turned to the southeast, heading
upstream along the valley of Bol'shoi Stream. Here, as in the valley of
the Gornaya River, his route was almost a straight line: the animal mainly
walked along a road. In only one place, near Evseeva Stream, was a deviation
to one side observed where the animal made a small looped path that included
a long rest period. Passing along the valley of Bol'shoi Stream and reaching
the mouth of a small left tributary [Petrov Stream (Yurta Stream)] of this
stream, the animal abruptly changed direction.
He moved toward the west following the course of the valley of Petrov
Stream. Having surmounted the divide between Bol'shoi and Igristyi Streams,
he descended via the small valley of Zvuchnyi Stream (Nikolaev Stream)
to Igristyi Stream. He walked along the valley of Igristyi Stream to the
north (i.e., in a direction opposite to his route along Bol'Shoi
Stream). From the valley of Igristyi Stream, the tiger began gradually
to deviate to the northeast. Then the animal moved off again to the east,
crossing the mountain spurs of the left bank of the Gornaya River. Tracking
was discontinued here.
This time, the entire route of the male tiger "Emperor", which we followed
without interruptions, comprised 152 km. This path intersected the major
part of the long-term study site going in a direction from southwest to
northeast. The middle section of the route that we followed ran as either
straight-line or as a completely arched path: abrupt turns were not present
here. The extreme sections of route, both the northeast and the southwest
sections, are drawn on the map as curves, or arcs.
Here the structure of the animal's route became complicated; it is precisely
here that the most abrupt turns were observed. In a series of instances,
sudden turns were observed when the animal entered a valley lying crosswise
to the direction of his path, or at points where two valleys merge (i.e.,
where a confluence of streams occurred).
Taken as a whole, the movements of male tiger "Emperor" during the course
of the winter season of 1971-1972 cannot be inscribed in any sort of regular
geometric figure. In its external contours, the network of his movements
reminds one more than anything of a very greatly elongated and arched ellipse
(cf., Fig. 6). The apex of this arc coincides,
generally speaking, with the divide between the Gornaya and Orekhovka Rivers.
From here, one of the projections of the ellipse stretches out toward the
south, the other extends to the northeast. The main routes of male tiger
"Emperor" are also oriented along the long axis of the ellipse in question.
These routes mainly extend along the crests of mountain ridges and spurs,
but sometimes they "cut" them almost perpendicularly (e.g., in the upper
reaches of Bol'shoi and Khvoinyi Streams).
From the divide between the Orekhovka and Gornaya Rivers, the animal
moved away to the south for the greatest possible distance (14.5 km.).
Then this tiger moved to the north for a distance of 22.5 km (as measured
along a straight line). The greatest width of the zone enclosing the routes
of this tiger is 14 km, while the minimum width is 2 km. The maximum distance
(as measured along a straight line) between the extreme points of the tiger's
routes in a direction from southwest to northeast comprises approximately
40 km. This tiger's travels during the winter in question encompassed
the basins of two large rivers: from the left tributaries of the Gornaya
River to the right tributaries of the Orekhovka River.
The routes of male tiger "Emperor" that we had tracked the previous winter
lie approximately in the central part of the network of his movements as
these were revealed in 1971-1972. An exact repetition of this tiger's movements
from the previous year was also noted on the following sectors: the road
from Bogdanov Stream to the mouth of Bol'shoi Stream, the crossing point
for the divide between the Orekhovka and Gornaya Rivers, the path along the
wedge of Kolonkovyi Stream near the fork that lies closest to its mouth,
and the path along the slopes of the right bank of the Gornaya River above
Kolonkovyi Stream. The route of this tiger often ran across the upper reaches
of Bol'shoi Stream.
The total length of the travels of the "Emperor" tiger, as established
from tracking during the winter season of 1971-1972, comprises approximately
335 km, which were walked by the animal over the course of 30-35 days.
More than 10% of the total length of the routes is taken up by the travels
of the male tiger walking together with the tigress or else following along
her tracks. For the entire route, the tiger crossed 78 valleys of streams.
This tiger crossed the valley of the Orekhovka River twice, and he crossed
the valley of the Gornaya River four times. The animal surmounted the divide
between the two rivers indicated (i.e., the Orekhovka and the Gornaya)
on four occasions. This tiger crossed 30 mountain spurs (lying mainly at
an elevation of about 500 m above sea level). And he crossed a ridge at
an elevation of approximately 800 m above sea level (the interfluve between
Bol'shoi and Igristyi Streams), where the elevational difference between
the ridge and the stream beds was 400 m.
The Winter Season of 1972-1973: In this season, our tracking
of male tiger "Emperor" began only on January 11. From the valley of Malyi
Klyuch Stream, the animal walked toward the valley of the Gornaya River.
However, he did not go across the valleys of Bol'shoi and Bogdanov Streams
but rather went across Kamennyi Stream, i.e., to the west of his
well-known route (cf., Fig. 6).
His path from Malyi Klyuch Stream was at first directed toward
the west, but soon, after the ascent of the divide, he abruptly turned
toward the south. Thus, the route also generally stretched along to the
Gornaya River. On a spur between Levyi and Pravyi Kammenyi Streams, where
the tiger investigated wild boar dens, a doubled path and a loop were noted.
Along the valley of the Gornaya River, the animal at first moved toward
the east but immediately turned again toward the south. Crossing a spur,
he entered the valley of Bol'shoi Stream. The tiger walked upward along
the valley of Bol'shoi Stream (i.e., toward the southeast) for a
distance of about 2 km after which he abruptly turned toward the northeast.
Going in this same direction, he again soon descended across mountain spurs
into the valley of the Gornaya River. He moved along a road in an easterly
direction. Above the mouth of Kolonkovyi Stream he turned into a narrow
side valley. Here, we noted several long rest stops by this tiger. Here
it was that we followed a doubled path of length 1.5 km. From the "free"
end of the doubled section, the path of the tiger ranged toward the northwest
across Kolonkovyi and Bogdanov Streams and farther into the valley of Bol'shoi
Stream (in the basin of the Orekhovka River). The path of the animal along
the valley of the Gornaya River and its adjacent slopes forms, in this way,
a sort of basis for drawing the routes of the tiger as a rectangle that is
stretched out toward the northwest.
Moving toward the northwest, the tiger walked mainly along those
routes that were known to us from tracking done in prior years. In the
basin of Bol'shoi Stream, before the right tributary that follows (downstream)
after Zimoveinyi Stream, a looped path was observed. From the "loop", the
animal turned toward the west, toward the side nearest Malyi Klyuch Stream.
Tracking was discontinued on the slopes that extend toward Malyi Klyuch
Stream. The 60 km- long path of the animal that we traced forms almost
a closed circuit, reminding us of the outline of a distorted rectangle.
Our continuation of the tracking of this tiger took place during the
second half of March. His footprints were found on a well-known site:
on the road along the valley of the Gornaya River between Kolonkovyi and
Bogdanov Streams. From here, the tiger went up to the mouth of Bol'shoi
Stream (in the basin of the Gornaya River), ascending along it for a distance
of 4.8 km. Then, over a distance of 0.3 km, he descended and moved off
toward the southwest. On the crest of a projecting spur along his route,
which was directed upwards along the valley of Bol'shoi Stream, was found
a long term laying place. Moving in a southwesterly direction, across
the mountain spurs of the left bank of the Gornaya River, the tiger crossed
into the basin of Igristyi Stream, where our tracking was discontinued.
The path of the animal on this sector approximately corresponds to the course
of the valley of the Gornaya River. Two abrupt turns were linked to orographic
"landmarks": the convergence of valleys.
Tracking was continued after a short interruption, beginning
at the mouth of Kammenyi Stream. From here, moving along the course of the
valley of Kammenyi Stream, the tiger went across the divide emerging into
the upper reaches of Razboinik Stream, a right tributary of the Gornaya River.
This section of the path is precisely oriented toward the north. From the
upper reaches of Razboinik Stream, the animal walked to the northeast, and
soon crossed over into the area around Malyi Klyuch Stream. Farther on,
he approximately repeated his route of the previous year, going across Bol'shoi
Stream to Khvoinyi Stream. The most abrupt change in the direction of his
path (an arc toward the side of his path) was caused by an encounter with
a human.
From Khvoinyi Stream, the animal traveled (along a route that we were
unable to completely determine) into the basin of Bystryi Stream, where he
continued his path in the very same easterly direction. The tiger crossed
the valleys of Kazachkov and Srednyi Streams at almost a right angle. Farther
on, in the valley of the Bystryi Stream, the male tiger came to a site where
a tigress with a cub stayed constantly. Here, he was disturbed on several
occasions by a human. On this sector, the tiger's line of movement became
more complicated: from the valley of Bystryi Stream, he headed across mountain
spurs toward the south, but he soon turned toward the west.
The entire long route of male tiger "Emperor" that we tracked during
March is reminiscent in its general orientation of routes of previous years,
but it nevertheless does not completely overlap with them. Once again,
the long axis of his extended travels was oriented from southwest to northeast.
Again, his "curving" of the route toward the southwest coincided with the
left bank of the middle course of the Gornaya River. The northeasterly
"curving" this time occurred not along the right bank of the Orekhovka River
but, rather, somewhat farther to the south, in the basin of Bystryi Stream.
On the whole, male tiger "Emperor" traveled just as widely during the
winter season of 1972-1973 as during the previous winter. Of those sectors
that he had visited in the previous year, he was only absent this year from
the right bank of the Orekhovka River, where he used to walk earlier (i.e.,
the previous year) with the tigress. At the same time, new routes that
had not been observed in previous winters were observed. Such novel paths
include the route between Gornaya River and Malyi Klyuch Stream across the
valley of the Kammenyi Stream, the travels across the mountain spur between
the Gornaya and its tributary, Bol'shoi Stream, and also the journeys that
were confined within a triangle of land between Srednyi and Bystryi Streams.
The longest routes linked the valley of the Gornaya River and the basin of
Malyi Klyuch Stream, Igristyi--Bol'shoi Streams in the basin of the Gornaya
River, and Malyi Klyuch-Bystryi Streams in the basin of the Orekhovka River.
The entire route of the "Emperor" tiger that we had followed during this
season added up to about 126 km. The animal surmounted 25 mountain ridges
and spurs of varying elevations, and he crossed the main divide (between
the Gornaya and Orekhovka Rivers) three times. This tiger crossed 39 streams
and crossed the valley of the Gornaya River three times. The extreme points
of his routes lay at a distance from each other of approximately 30 km (as
measured along a straight line).
Conclusions from Three Winter Seasons: The territory of this
male tiger was rather clearly confined to the central part of the basin
of the Gornaya River and to mountain ridges along the left tributaries of
the Orekhovka River (cf., Fig. 6). The area,
within the limits of which the "Emperor" tiger traveled, is generally reminiscent
of a greatly extended and not entirely regular ellipse. The long axis
of the ellipse is oriented from southwest to northeast and extends for
a distance of approximately 40 km. The greatest width of the ellipse is
about 20 km, and its total area is close to 500 km2. If we
take into account information derived from interviewing people and single
encounters with the tracks of the "Emperor" tiger beyond the limits of the
area indicated, then the territory will be somewhat larger.
The "skeleton" of the territory is formed by a system of constant travels,
the majority of them connecting neighboring river valleys and streams.
These periodically repeated routes were supplemented by those branches of
the main routes that were used rarely or even walked only once. The tiger
traveled between the basins of the Gornaya and Orekhovka Rivers along three
paths. Most often, the animal utilized a route from Bogdanov Stream to
Bol'shoi Stream; more rarely, he followed routes from Kammenyi Stream to
Malyi Klyuch Stream or from Kolonkovyi Stream to Bol'shoi Stream. The "Emperor"
tiger also walked along these same paths in the reverse direction. As an
example, he passed from Malyi Klyuch Stream into Bystryi Stream along one
and the same route.
Apparently, there existed still one more path between the basins of the
Gornaya and Orekhovka Rivers, though it was not followed in its entirety
during tracking. The footprints of the "Emperor" tiger were repeatedly encountered
in the valley of Kostyukovskii Stream (a tributary of the Gornaya River)
and along Srednii Stream [a tributary of Bystryi Stream (in the basin of the
Orekhovka River)]. The direction of movement of the tiger in these instances
allows us to hypothesize that sections of the path can converge along the
sectors indicated. Their unification would indicate the existence of the
shortest possible path from the basin of the Gornaya River into the valley
of the Bystryi Stream. However, the footprints of the "Emperor" tiger were
encountered here principally during autumn; in winter a very deep snow layer
lies on the ridges separating these streams. The travels of the "Emperor"
tiger between the Igristyi and Bol'shoi Streams took place via two different
routes.
The total tracked path of this tiger comprised about 540 km.
2. The "Lazy" Tiger: The tiger that is designated by this name
had a width of the big sole cushion of his front paw equal to 11.5 cm. During
tracking, certain specific behavioral features also appeared: a distinctly
expressed preference for traveling along roads and a very large number of
resting (laying) sites. Later, when the corpse of the "Lazy" tiger was examined,
pathological changes were discovered in the bones of his limbs.
The Winter Season of 1972-1973:
The first footprints of this tiger were encountered on November
25, 1972, on a wedge between the branches of the upper reaches of Bol'shoi
Stream in the basin of the Gornaya River. On November 24, there was a major
snowstorm, which continued for almost the entire day. During the snowstorm,
the animal lay for a long time under a Korean pine tree along the right
bank of Bol'shoi Stream. From here, moving mainly along roads, the "Lazy"
tiger descended into the valley of the Gornaya River and walked upwards
along it to the second (after Kolonkovyi Stream) right tributary of this
river (Fig. 7). He succeeding in covering a distance
of 23 km to get to the site indicated from the upper reaches of Bol'shoi
Stream. From here, we tracked a looped path along a spur-"wedge" of length
2.4 km with a return to the road. The tiger spent the day within the limits
of this "loop". He returned to the road 300 m. lower from the point of ascending
the spur. Moving mainly along the road, the "Lazy" tiger returned to the
lower reaches of Bol'shoi Stream, from which area he had recently come.
Again, he changed his direction to the opposite one and now moved along that
same road upward along the course of the Gornaya River. In this way, he
walked the section of the road between the crossings near the mouths of
Bol'shoi and Bogdanov Streams for the fourth time over the course of a 24-hr
period.
The "shuttle-like" movements of the tiger
along this segment of his route only ceased when, avoiding Kolonkovyi Stream,
he turned from the road to the right at a distance of 3 km from this stream.
Proceeding in a southwesterly direction, the "Lazy" tiger began to ascend
the slope of the mountain ridge that divides the narrow side valley of Kazachkov
Stream from the valley of the Gornaya River. Having surmounted the divide,
he descended along the valley of Kazachkov Stream toward Bol'shoi Stream,
and following the road along it he began moving up the stream. Here, he
once again repeated the route that he had recently walked. Thus he reached
the "wedge" in the upper reaches of Bol'shoi Stream, the location from which
our tracking had begun.
Moving across the upper reaches of the right branch of Bol'shoi Stream,
the "Lazy" tiger ascended the divide between the two relatively large river
basins: the Gornaya and Malinovka Rivers. From here, he moved in the direction
of Levyi Skal'nyi Stream (in the basin of the Malinovka River). Crossing
the stream, he walked along its left bank toward the east. The entire segment
of the path of this tiger that is described here totaled approximately 85
km, which he walked primarily along roads. The animal spent less than three
days on this path.
Tracking was continued when we discovered the footprints of the "Lazy"
tiger along the middle course of the Komsomolka River, a left tributary of
the Malinovka River. He descended from the slopes of the right bank of this
river and emerged onto a road within 7 km from the mouth of this river. This
took place on the night of December 11-12, 1972. The tiger walked upward
along the river channel for several kilometers. Then he turned in a northeasterly
direction on a spur-"spit". Ascending, the "Lazy" tiger reached a ridge
going toward the narrow side valley of a neighboring stream, also a tributary
of the Malinovka: Valun Stream. Coming out into the valley of Valun Stream,
the tiger traveled upward over approximately a kilometer-long segment of
the path along the terrace of this stream, and then descended along a road.
From the site where he had emerged onto the road, he changed direction several
times (his line of movement became abruptly zigzag in its form), but soon
he headed upward along the valley of Valun Stream. After we had followed
approximately 3 km of the tiger's path along the road, tracking was discontinued.
The entire path from the valley of the Komsomolka River amounted to 18 km.
The remaining unknown part of the travels of the "Lazy" tiger obviously
lay along the interfluve of Valun Stream and the Komsomolka River. We succeeded
in continuing our observations on this tiger from the upper course of the
left branch of the valley of the Komsomolka River. The animal walked upward
along the road and turned to the right along its path moving along a small
brook to the southwest. Using this path, the "Lazy" tiger probably ascended
up to the divide between the basins of the Malinovka River and the Otkosnaya
River (a tributary of the Zhuravlevka River). Tracking was discontinued
before we reached the divide. The tiger turned around somewhere in the neighborhood
of the divide and walked back along his own tracks.
Moving downward along the road, he descended almost to the fork
of the Komsomolka River, from which the animal moved away to the left along
its route in a looped path (within the borders of this section was found
a long-term resting site). Passing along the valley of the Komsomolka River,
the tiger approached its mouth, where, going in a northeast direction and
having surmounted a steeply sloping spur, which projected like a promontory
between two merging valleys, he emerged at the Malinovka River. He walked
upward along this river in a northeasterly direction. The animal maneuvered
along a segment between the channel of the river and an exit onto a road
in the neighborhood of Shirokii Stream. Repeatedly lying down, in some cases
for a long rest, he scratched trees, rubbing himself against them. This
all occurred on December 16.
The subsequent path of the "Lazy" tiger lay upward for a distance of about
20 km along the valley of the Malinovka River. At the end of this segment,
he crossed the valley and ascended along the right bank of a steep spur-"spit",
where he laid down for a long time (December 17).
Figure 7. Schematic map of the movements that we tracked during the winter
seasons of 1970-1973 for three tigers.
1) The "Miniature" Tigress in 1970-1971
2) The "Miniature" Tigress in 1972-1973
3) The "Lazy" Male Tiger in 1972-1973
4) The "Powerful" Male Tiger in 1972-1973
From here, he still walked upward for a while along the course
of the river, and then turned to the left in his path, heading generally
toward the north. He ascended, at first along the valley of the right tributary
of the Malinovka River and then along a spur-"spit" onto the very highest
crest of the mountain ridge dividing the valley of the Malinovka River and
its tributary, Skal'nii Stream. In all probability, the "Lazy" tiger was
heading along this path toward the basin of the Gornaya River, but the path
turned out to be too difficult, and he turned around to go back. This crest
reaches an elevation of almost 1000 m. above sea level, and the depth of
the snow cover here was about 65 cm. Having twice made an attempt to force
his way through to the Gornaya River, the "Lazy" tiger turned around for the
last time (over a distance of 50 m) and walked along the ridge in the direction
of Skal'nii Stream.
Smoothly changing his "course", he returned via an almost circular path
to the "wedge" along which he had ascended. Walking for a while along his
own tracks, he descended back into the valley of the Malinovka River. The
length of the entire loop amounted to approximately 10 km.
The tiger moved downward along the valley of the Malinovka River. Upon
reaching Skal'nii Stream, he walked upward along it, keeping to the road.
Having reached the sources of Pravyi Skal'nii Stream, the "Lazy" tiger this
time was able to cross the divide in a northwesterly direction. Thus, he
turned up on a spur between converging narrow valleys in the upper reaches
of Bol'shoi Stream (a tributary of the Gornaya). He spent December 20-21
here. The entire route tracked for this tiger across the basin of the Malinovka
River comprised 97 km.
Heading from here toward the southwest, the tiger crossed the
spur between Bol'shoi Stream and its left tributary, Malya Yurta Stream (Kruglyakov
Stream). Going around the upper reaches of the latter stream, the "Lazy"
tiger changed his direction of movement toward north and, passing across
a spur on the left bank of the stream, reached the mouth of Petrov Stream
(Yurta Stream), where he emerged onto the road. From here, he traveled across
a "wedge" and crossed over onto a road that ran along the valley of Bol'shoi
Stream. This road led him onto a trail running along the valley of the
Gornaya River, where he had previously walked about a great deal. Now,
the tiger walked toward the east along this track. Passing a narrow side
valley of Bogdanov Stream, he turned to the right in his path into Yasenevaya
Pad' (pad':a deep and narrow forested valley). He passed along the road on
December 27. His entire path from the ridge amounted to 32 km.
From Yacenevyaya Pad', the "Lazy" tiger returned across the spur between
the valleys of the Gornaya River and Bol'shoi Stream into the valley of the
latter stream. Here he spent the morning of December 28. He traveled along
a mountain ridge on the left bank of Bol'shoi Stream into the lower reaches
of Petrov Stream, a left tributary of Bol'shoi Stream. He ascended along
a road in the valley of this stream up to its branching point, and farther
along on a spit, he headed toward the divide between the basins of Bol'shoi
and Igristyi Streams. From the divide, he descended into a narrow side
valley of Zvuchnyi Stream (Nikolaev Stream, a tributary of Igristyi Stream)
and got as far as its mouth. From here, the tiger, having abruptly changed
his direction, walked upward along Igristyi Stream. A V-shaped projection
that is turned toward the south depicts his path across the divide between
Pravyi and Levyi Igristyi Streams. Walking in an arc along the right bank
of Levyi Igristyi Stream, he once again began to ascend onto the divide, going
toward Pravyi Igristyi Stream. Tracking was discontinued here. The tiger
had walked a distance of approximately 40 km from the valley of the Gornaya
River to this place.
The "Lazy" tiger traveled by a route that
we did not succeed in determining from here into the basin of Malyi Klyuch
Stream, where he proved to be on the trail of another male tiger: the "Emperor"
tiger, which had walked in the direction of the Gornaya River. In places
departing from the track of the "Emperor" tiger, but mainly adhering to his
track, the "Lazy" tiger descended along a "wedge" into the valley of this
river. Crossing the valley, he emerged onto a road that runs along Bol'shoi
Stream just above its crossing point and proceeded along it up to Petrov
Stream, where he spent the night of January 11-12. The "Lazy" tiger went
upward for a distance of about a kilometer along a road that had been laid
down along the valley of Petrov Stream, farther on heading toward the slopes
of the right bank. He now moved along a track made by wild boar in the direction
of Igristyi Stream. Walking along a slope for approximately 2 km, he abruptly
turned to the left on a hill, emerged onto another wild boar track and made
his way along this track. Within a distance of 300 m, he collided with
another male tiger: the "Powerful" tiger. A fight arose between them in
which the "Lazy" tiger was killed (in Fig. 7, the sites
of the tiger fight and of the death of the "Lazy" tiger are marked with daggers).
The total path that we followed for the male tiger designated with the
hypothetical name "Lazy" amounted to approximately 290 km. Over this distance,
the animal crossed the channels of small streams 40 times, traversed the
largest rivers in our study site 4 times, and surmounted 22 mountain spurs.
The tiger traversed the divide between the Gornaya and Malinovka Rivers three
times, and he crossed the divide between the Gornaya and Orekhovka Rivers
once. The extreme points in his routes (as measured along a straight line)
lie at a distance of 45 km (north-south) or 25 km (west-east) from each other.
Thus, the "Lazy" tiger ranged widely. An attachment to routes passing along
the valleys of rivers and streams (more precisely, to the roads laid down
along them) was especially characteristic of this tiger (cf., Fig. 7). Travels along roads constituted more than a third
of the path of the "Lazy" tiger; often, he would walk along them repeatedly.
The routes of this tiger are distinguished by a lesser degree of orderliness
than the travels of the "Emperor" tiger. It is difficult to visualize the
external boundaries of a territory using these routes. The only thing that
is clear is that he walked within the limits of the territories of the "Emperor"
tiger and of another male (the "Powerful" tiger), a fight with the latter
male costing the "Lazy" tiger his life.
3. The "Powerful" Tiger: The tiger designated by this hypothetical
name had a width of the big heel cushion of his front paw equal to 12 cm.
The path of this tiger was followed only in the neighborhood
of the fight (up until the fight and after it). The "Powerful" tiger descended
from the "wedge" between the branches of Petrov Stream and crossed the right
one in its upper reaches (cf., Fig. 7). Farther
on, he walked downward over the slopes of the right bank into the valley,
and, when he was about opposite the fork of Petrov Stream, he encountered
the "Lazy" tiger on a wild boar track. After the fight, in which he came
out on top, the "Powerful" tiger walked back in the opposite direction (i.e.,
along his own former track). He crossed the stream, which flowed to the
right below the fork of Petrov Stream, and sat down on the track. Blood spots
remained on this site. After going a distance of 500 m after crossing the
stream, he lay down on the wild boar den, where traces of blood were also
found. Farther along, moving along right bank slopes, he crossed into the
upper reaches of the right branch of Petrov Stream. Then, with an arching
path, he headed toward the left, where he soon approached a shelter, which
was situated not far from the divide. The tiger utilized this lair repeatedly.
He spent several days here. From here, he ascended onto the divide and,
having crossed it, descended into the valley of Zvuchnyi Stream. The path
that we tracked for the "Powerful" tiger amounted to 12 km.
Several older tracks of both the "Powerful" tiger and a tigress
were also observed on the slopes of the valley of Petrov Stream. They had
lived here up until the appearance of the "Lazy" tiger. The "Powerful"
tiger primarily inhabited the basin of the Malinovka River and had crossed
over into Igristyi Stream. During August, 1973, his footprints were observed
in the valley of Valun Stream, a tributary of the Malinovka River.
* * *
The length of the routes of the male tigers that we tracked over three
winter seasons added up to about 800 km. All the paths that we followed
lie within the boundaries of an area of 1000-1200 km2 (cf.,
Figs. 6 & 7). The sizes of
the territories of the males were unequal, but, apparently, dimensions on
the order of 35 km x 20 km (i.e., approximately 600-800 km2)
are typical for them.
When traveling about their territories, male tigers use relatively stable
routes, repeating them on individual segments with a high degree of accuracy.
The tigers will reappear on one site or another after a definite interval
of time (from 7-15 days to up to a month). Those sections of the territory
along which tigers travel regularly are covered by a rather uniform network
of routes; but there also remain areas within these sectors where the animal
never goes or where he appears only rarely. The dimensions of such "blank
spaces" are, as a rule, not greater than 4 km2 (sometimes up
to 16 km2). Most often, these sites are adjacent to high mountain
spurs that reach elevations of 1000 m or more above sea level. The maximum
distances covered by the tigers when moving along the long axis of the territory
in a single direction reached 80-110 km.
Tigresses:
1. The "Empress" Tigress: The sex of this animal was established
from the very beginning by the presence of offspring. The width of the
big sole cushion of her front paw was 9.5 cm.
The Winter Season of 1970-1971: Reports of the discovery of tracks
of very small tiger cubs, belonging, without a doubt, to the litter of the
"Empress" tigress, had already reached us by the autumn of 1970. The tracking
of this litter was begun on February 15, 1971, along the right bank of the
slopes of the valley of the Gornaya River between Kolonkovyi and Strel'tsov
Streams (Fig. 8).
Moving along the slopes in a northwesterly direction across the
upper reaches of small right tributaries of the river, the tigers emerged
onto a road in the valley of Kolonkovyi Stream near the fork of this stream
that lay closest to the mouth of the stream. From here, they headed for
the upper reaches of Bol'shoi Stream, their path along this sector being
coincident here with the route of the male "Emperor" tiger that we have previously
described. Before reaching Bol'shoi Stream (where they came upon the remains
of a bear, which had been killed by the male), the tigress with her cubs
had crossed the channels of eight small streams, crossed five mountain spurs,
and traversed the divide between the Gornaya and Orekhovka Rivers. The family
had walked approximately 30 km from the Gornaya River up to the site where
the prey was located. Tracking was continued after five days, when the animals
descended into the valley of Bol'shoi Stream, and then their footprints were
discovered on the divide opposite to the upper reaches of the first right
tributary (going from the mouth) of Kolonkovyi Stream. Observations on the
life of this tiger family were then interrupted and were resumed only in
the middle part of March.
The tracks of a female without cubs were discovered on March
14 on the right bank slope of the valley of Bol'shoi Stream, approximately
2 km from its confluence with Malyi Klyuch Stream. Moving first along the
slopes, then along the bottoms of the valleys, she ascended up to the fork
of the narrow side valleys at the sources of the Bol'shoi Stream. Going
from there downward along the valley, the tigress ascended to a saddle-shaped
spur, which extended between Bol'shoi Stream and Malyi Klyuch Stream; the
tigress descended into the valley of the Malyi Klyuch Stream, heading downward
along it, but she soon turned into a narrow side valley of the right tributary
(the first one from the fork of the Malyi Klyuch). Farther along the right
bank of Kholodnoi Stream, she once again ascended onto the divide between
Malyi Klyuch and the Bol'shoi Streams. This was precisely that crossing
point over which the male "Emperor" tiger had passed on many occasions.
The entire sector of the tigress' route described here is distinguished by
its high degree of arching, but, on the whole, her path line from Bol'shoi
Stream to Malyi Klyuch Stream and back had a horse-shoe shaped trace with
a projection oriented toward the east.
Descending from the ridge, the female went into the valley of Bol'shoi
Stream, crossing it lower down below the mouth of Zimoveinyi Stream, and
moving along the slopes of the right bank downward along the valley. At
a distance of approximately 2 km from the confluence of Bol'shoi and Malyi
Klyuch Streams, tiger cubs tracks appeared along her path. A human frightened
the recently-reunited family away from the kill site on March 16.
Figure 8. Schematic map of the movements that
we tracked in the winter seasons of 1970-1974 for two families of tigers.
Movements of:
1) The "Empress" Tigress with her cubs and without her offspring in 1970-1971
2) The "Empress" Tigress in 1972-1973
3) The "Empress" Tigress with her cub in 1972-1973
4) The "Unknown" Tigress with her offspring
5) The "Empress" Tigress with her cub in 1973-1974
6) Sites Where the Cubs Stayed for Long Periods
The travels of the family that we later tracked, and also the movements
of the tigress and her cubs that have already been described, characterize
their life during the course of the period of our study in the following
way. From the moment of their arrival at the remains of the bear and over
the course of the succeeding 1.5 months the tigers did not leave the basins
of Malyi Klyuch and Bol'shoi Streams. The animals passed across the divide
between these streams by two paths: one of them was indicated above during
the description of the tracking of the tigress, and the other lay along the
valley of Kholodnoi Stream. The footprints of the tigers were traced along
the valley of Malyi Klyuch Stream and along its slopes up to the mouth of
Kholodnoi Stream and a little above the fork, while along the slopes of the
valley of Bol'shoi Stream mainly below the mouth of Zimoveinyi Stream. Within
the limits of the area that we studied, it is possible to distinguish four
areas where the tiger cubs stayed for a long time: 1) the upper reaches of
Bol'shoi Stream, 2) the right-bank slopes of the valley of Bol'shoi Stream
below the mouth of the tributary that lies just beyond Zimoveinyi Stream,
3) the left bank slopes of Malyi Klyuch Stream opposite the outfall of Kholodnoi
Stream, and 4) the region around the fork of Malyi Klyuch Stream (cf.,
Fig. 8). In the latter instance, tigers cubs tracks
were distributed over an area that was up to 1 km in length and up to 200
m in width.
The path of the tigers that we tracked during the second half of this
winter added up to a distance of approximately 140 km. Over half of this
distance is taken up by the travels of the female without her cubs. All
the routes of the offspring in the basins of Malyi Klyuch and Bol'shoi Streams
can be inscribed within a rectangle of dimensions 7 km x 8 km. In other
words, over the course of one and a half months, the animals did not go beyond
the borders of an area of about 60 km2. Their passage from the
slopes of the Gornaya River into the upper reaches of Bol'shoi Stream was
the only movement tracked by us that lay outside of this sector. Traveling
about in this area, they repeatedly utilized their own tramped tracks and
the tracks of the male. In the majority of cases, the female walked about
the territory without the tiger cubs. The cubs kept to the neighborhood
of the lair during this time or stayed near an animal that had been killed
by the tigress. After a successful hunt and the return of the female, the
family traveled to the new kill site.
The Winter Season of 1971-1972: During this winter, the tracks
of the female with her offspring were first encountered on a mountain spur,
which stretched along the left bank of Malyi Klyuch Stream (cf., Fig. 8).
The animals emerged onto the spur opposite to the source of Rybakovskii
Stream, having ascended from the valley of Malyi Klyuch Stream. From there,
the female (without the cubs) headed along a spur toward the south. Her path
ran across the upper reaches of Razboinik Stream and the valley of Pravyi
Kammenyi Stream; from where she started toward the northeast. The male "Emperor"
tiger followed on the trail of the tigress in the upper reaches of Malyi Klyuch
Stream. They went along an identical route until reaching the mountain spur
on the right bank of Zimoveinyi Stream. Farther on, the tigress descended
along a spur into the valley of Bol'shoi Stream and traveled along the slopes
of its left bank. Going primarily downstream from here, she reached the valley
of the Orekhovka River. The female headed upward along the channel of the
stream toward the east. The tigress appeared on the Orekhovka River on November
19; beginning from the place where the southerly direction of her movements
changed to a northeasterly one, she covered a distance of 35 km.
After she followed her route along the valley(in part along a
road) up to Khvoinyi Stream, the female turned into the valley of this stream;
but, farther on, across a ridge in the upper reaches of the first (from the
mouth) left bank tributary of Khvoinyi Stream, she returned to the valley
of Bol'shoi Stream. She descended toward the channel of the latter stream
near the first (from the mouth) tributary on the right. In this way, the
"Empress" tigress completed a circular route, the length of which comprised
25 km. Crossing the valley of Bol'shoi Stream and the "wedge" between the
latter and Malyi Klyuch Stream, the tigress headed off toward the right bank,
then moved off toward the slopes of the left bank, going upstream. She found
her cubs on a spur in the upper reaches of Rybakovskii Stream.
The entire path described for this female, which in its outline is reminiscent
of a figure-eight pattern, comprised about 70 km. Then the footprints of
the offspring were observed on the right bank of Malyi Klyuch Stream just
above Kholodnoi Stream. Here, observations on the tigress and her cubs were
interrupted. We succeeded in renewing our observations of this family only
after an interruption of two months. During the course of this two-month
period, repeated transits by the tigress from the Bystryi Stream side to the
left side of Malyi Klyuch Stream and back occurred. The paths across the
valley of Malyi Klyuch Stream ran near the mouth of Kholodnoi Stream, and
those across Bol'shoi Stream lay in the region beyond the right tributary
that followed after Zimoveinyi Stream.
Tracking was continued when on January 22, 1972 (after noon), the
tigress crossed the valley of Bol'shoi Stream exactly in the neighborhood
of the tributary that was mentioned previously. From here, she moved in
a generally easterly direction. The tigress traversed the basin of Khvoinyi
Stream, and then, having surmounted still another spur, she emerged into
the upper reaches of a left tributary of the Bystryi Stream (the first one
beyond the mouth of this stream). From here, the "Empress" tigress returned
to the saddle-shaped "wedge" between the branches of Khvoinyi Stream along
her old track (or parallel to it). Then she turned for the third time back
along her previous path, from which she descended into the valley of Bol'shoi
Stream near the site where she had walked on January 22. The tigress returned
here during the morning of January 26, walking in a looped path that was
approximately 30 km in length. From the valley of Bol'shoi Stream, we tracked
her 13-kilometer route along Malyi Klyuch Stream and then across Kholodnoi
Stream, after which tracking was discontinued.
Observations were continued beginning on February 11 from a site
where day-old tracks of the "Empress" tigress were discovered near the mouth
of Yurta Stream (in the basin of the Orekhovka River). From here, her route
lay across the valley of the Orekhovka River and a mountain spur into a narrow
side valley of Bystryi Stream along which she walked quite far upstream, in
places making use of a road. Here, the tracks of a male tiger ran together
with the tracks of the "Empress" tigress. Together, they turned to the left
in their path, onto steep southern slopes where tracking was interrupted.
The tigress walked for a distance of 17 km from the valley of the Orekhovka
River.
The tracked segment of the path that followed after the interruption began
from the left branch of Khvoinyi Stream (along its upper reaches), where the
tigers had walked approximately 10 days later. The "Empress" tigress walked
together with the male from Khvoinyi Stream across the ridge and along a
spur on the right bank of Bogdanov Stream. The tigers moved one after another
taking turns leading up to the ridge near Bol'shoi Stream, then the male
occupied the position of "leader" for a long time. The tigress left the
path of the male on a spur opposite the fork of Bogdanov Stream (i.e.
when she was already in the basin of the Gornaya River). In this basin, she
walked across the upper reaches of Levyi Kamennyi Stream; from here, she
returned to Malyi Klyuch Stream, in the upper reaches of a right branch of
the latter stream. The tigress crossed over a spur into the upper reaches
of Razboinik Stream (in the basin of the Gornaya River). On this segment
of the route, which had a total length approximately 40 km, the direction
of her movements changed from a southerly one to westerly, northerly, and
then northwesterly. With a route of complex outline, she twice crossed the
divide between the Gornaya and Orekhovka Rivers.
Her path also remained curved later on. The path ran from Razboinik
Stream across the divide between it and Rybakovskii Stream in its middle course,
then across the upper reaches of Rybakovskii Stream onto Malyi Klyuch Stream,
Bol'shoi Stream, and, by then already running along the track of the male
that she had encountered, to Khvoinyi Stream. The animals walked across
the ridge to Khvoinyi Stream along their old tracks, which they had left
7-9 days earlier when traveling in the opposite direction. From the ridge,
the tracks of the male and female again ran together all the way up to the
road along the valley of the Orekhovka River. The tigress took about 3 days
to cover the entire route from Razboinik Stream up to the Orekhovka River,
a distance of about 40 km.
Both tigers crossed the Orekhovka River and ascended along its right bank
onto a mountain spur between Pravaya Sobolikha and Levaya Sobolikha Streams.
It was precisely here along this mountain spur that their "wedding" occurred
on March 2-6. From here, the animals, moving in a generally southeast direction
and already using a new path, returned to the road that ran along the valley
of the Orekhovka River, where their tracks separated. The tigress walked
along the road toward the east. After walking for 8 km in this direction,
passing Semkin Stream (which flows into the Orekhovka River on the right),
she turned along the slope to the left in her path (i.e. toward the
north). Here, she made a complex loop along spurs that enclosed the valley
of Semkin Stream on the left and on the right, and then she walked in a northerly
direction along the valley of the Podgornaya River (which flows into the Orekhovka
River below Semkin Stream). Moving mainly along the left bank of the Podgornaya
River, she walked up to its upper reaches, where observations were discontinued.
The tigress had walked 27 km from the site where the two tigers emerged onto
the road (where their tracks separated), and the entire path of the "Empress"
tigress from Razboinik Stream totaled approximately 95 km. The tigress needed
no more than 9 days to make this journey.
hThe picture of the movements of this tigress in the winter season of 1971-1972
differs in many respects from that observed in the previous winter. Moreover,
it underwent a substantial change over the course of just one particular
winter (cf., Fig. 8). At the beginning, her offspring
remained as before in the basins of Malyi and Bol'shoi Streams, although
the female began to travel more widely than she had in the previous year.
The dimensions of her territory approached 100 km2. The extreme
points of her travels lay at a distance from each other of 15 km (along the
long axis of the figure, the region marked in outline) and of 8 km (in width).
In the second half of the winter, the tigress began to travel over an ever-wider
area. The cause of this consisted, apparently, in the loss of the offspring:
the tiger cubs, as we later learned, had been shot by poachers in the valley
of Khvoinyi Stream.
The entire route that we followed over the course of the winter for this
tigress added up to about 280 km. Of this, about 200 km were walked after
the death of her cubs. More than a third of this 200 km was spent on joint
travel with the male. In total, the extreme points of her travels for this
season lay at a distance of 35 km from each other (as measured along a straight
line). The longest routes were oriented along a southwest-northeast line.
For the entire route that we tracked for her, the tigress surmounted 41 orographic
barriers (mountain ridges and their spurs), four times crossed over major
divides, 71 times crossed the channels of streams, and twice crossed a large
river. Abrupt changes in the direction of her path, which determined the
path of the animal for many kilometers, were observed in the following places:
1) on the slopes of the basin of the Gornaya River, the valley of which the
tigress did not enter even once during the period of observation, 2) in the
basin of Sobolikha River after the period she spent there together with the
male during her estrus, and 3) in the upper reaches of the Orekhovka River,
where she turned around before reaching the divide and remained in the basin
mentioned.
The Winter of 1972-1973: The tracks of this tigress, once again
with a litter [consisting of one cub (the width of its big sole cushion was
8.5 cm)] were first encountered only at the beginning of April along the
right bank of Srednii Stream near its confluence with Bystryi Stream (cf.,
Fig. 8). Tracking showed that the tigers had lived
for a long time (probably from January up until April) within a very limited
area that was not more than 15 km2. This sector was situated
as if it were enclosed within a triangle of land between Srednii and Bystryi
Streams (near their confluence). The animals kept mainly to the valleys
of these streams. While making observations during April, A. G. Yudakov
had several direct encounters with tigers from this family. The tracks of
another tigress (the "Unknown" tigress, with two cubs) were discovered on
the right bank of Kolyuchyi Stream (a right tributary of Srednii Stream that
is the third one from the mouth of this stream). A male also stayed on the
relatively limited area, where the two tigresses lived with their cubs.
At the end of November, 1973, the tracks of the two females with cubs and
the tracks of the male were discovered at the exact same site where they
had stayed during the previous spring. The tigress, on which we conducted
multi-year observations (the "Empress" tigress), descended along a tiger
path between Srednii and Bystryi Streams, and went farther along on the road
to the mouth of Srednii Stream. The tiger cub joined the female prior to
her emergence onto the road. Together, they crossed into the valley of Bystryi
Stream, crossing it and heading toward the slopes of its right bank. Tracks
of the female with the two cubs were also observed at this time in the upper
reaches of the Orekhovka River in the district around Podgornyi Stream.
Although the observations were broken off in late autumn of 1973, it is possible
to judge from them that, comparison with the previous spring, the litters
of cubs were already traveling more widely.
For the entire period of our observations, the tracked footprints of the
"Empress" tigress (with offspring or without them) added up to a distance
of 430 km. The travels of this tigress can be inscribed in an area on the
order of 300-400 km2. The maximum length and width that characterize
her territory are 35 km and 12 km, respectively.
2. The "Miniature" Tigress: The width of the big sole cushion
of this tigress was also 9.5 cm. She lived in an entirely separate territory,
and her routes did not intersect the movements of the "Empress" tigress even
once during the study period.
The Winter Season of 1970-1971: Her tracks were first encountered
on March 12, 1971, on a road in the valley of Pravyi Igristyi Stream (cf.
Fig. 7).
She came from the left bank of this valley at a distance of 2 km
above its confluence with Levyi Igristyi Stream. Having made a small loop
on the right bank of Pravoi Igristyi Stream, she walked upward along the
valley of this stream, using the road that had been laid down here. Avoiding
the mouth of Grustnyi Stream (Vorozhbitov Stream), the tigress changed from
a southeasterly direction to a southwesterly direction and crossed over a
spur into the valley of a tributary of Levyi Igristyi Stream. Going across
the upper reaches of Levyi Igristyi Stream, she headed toward the basin of
the Malinovka River, where she also crossed over the divide and had begun
to descend into Mineralnyi Stream. The section of her path that we followed
equaled 34 km.
The Winter Season of 1972-1973: On January
12, the tracks of the "Miniature" tigress were discovered at the mouth of
Petrov Stream (cf., Fig. 7).
The tigress descended into the valley opposite the site of the fight
between the two large males. She did not approach the location of the fight.
From the mouth of Petrov Stream, she headed upward along the course of Bol'shoi
Stream up to its tributary, Bol'shaya Yurta Stream (Samosenkin Stream).
Moving along a narrow side valley of the latter stream, she reached the divide
between the Gornaya and Malinovka Rivers. Going in the direction of the
Malinovka River, the tigress began to descend along one of the left tributaries
of Shirokii Stream. Tracking was discontinued here.
On March 2, the tracks of this tigress were encountered in the
valley of the Komsomolka River, at a right tributary of this river that was
first from the mouth of the river. Keeping to the slopes, the "Miniature"
tigress headed toward the Malinovka River. She moved along the road downward
alongside the river but soon turned into the valley of a right tributary
of the Malinovka River: Pechenyi Stream. The tigress walked along the road
during the night of February 24-25. Farther on, she reached the upper section
of Pechenyi Stream, walking over a part of the route along the tracks of
a male. From here, she crossed into the upper reaches of the next tributary
(downstream from Pechenyi Stream) of the Malinovka River; in this case, the
highest point of her ascent brought the tigress to the top belt. The "Miniature"
tigress then crossed over this stream, and afterwards she crossed a spur
that had a large number of sheer rocks. She emerged onto the slopes of the
left bank of Mineralnyi Stream in its middle course. Farther on, keeping
to a generally northwest direction, the tigress went across the upper reaches
of several streams, which are right tributaries of the Malinovka River.
Near the sources of Zolotoi Stream, she approached the divide, beyond which
lay the valley of Levyi Igristyi Stream (a tributary of the Gornaya River).
This was the final point in our tracking. Up until this point, this tigress
had covered a distance of approximately 50 km from the valley of the Komsomolka
River.
In total, we walked a distance of about 100 km (cf., Fig 7) following the tracks of the "Miniature" tigress.
Over this distance, she surmounted 18 spurs, twice crossed a major divide,
and 24 times crossed the channels of streams and brooks. The extreme points
in her travels lay at a distance of 27 km from each other (as measured along
a straight line).
* * *
In its totality, we walked a distance of approximately 530 km following tigresses
over the course of three winters. It is more difficult to estimate the dimensions
of the territories of females than of males, since the territory sizes of
females can change a great deal depending on the presence of offspring and
on the age of the cubs. Thus, in the winter of 1970-1971, the movements
of the offspring of the "Empress" tigress were limited to an area of 60 km2
over the course of 1.5 months, but, from January to April in the 1972-1973
season, the tigress was already living with another litter of offspring on
an area of not more than 15 km2. The "Empress" tigress traveled
within the limits of a territory of up to 100 km2 with her second-year
offspring during the winter of 1971-1972. After the loss of her offspring,
she began to walk over an even wider area. The area that encompassed her
total territory approximated 300-400 km2. The cross-section of
the territory where a single tigress lived reached 27-35 km (data for two
individuals). This size slightly exceeds the cross-sectional length for
territories of male tigers. However, the area of the territories of the
latter, on average as well as maximally, is approximately twice as large.
Tigresses, like the males, lay down a network of permanent crossings within
the limits of their territories, although numerous repetitions of one and
the same route are observed to occur less often for tigresses. The intervals
between successive appearances of the animals at previous locations are shorter,
often only 3-5 days. On territory that has been taken over by offspring,
the tiger cubs keep for long time within defined, but periodically changing,
locations, the cross-sections of which do not exceed 1 km.
General Conclusions on the Structure of Tiger Territories: The use
of their territories by two adult tigers (the male "Emperor" tiger and female
"Empress" tigress) can be characterized in detail with observations made
over the course of three winter seasons (cf., Figs. 6 & 8). Less complete information
was collected on the movements of two more males and another tigress (cf.,
Fig. 7). Systematic tracking of the "Emperor" tiger
and the "Empress" tigress allowed us to determine in the case of each of
them the core area of the territory, where the animals appeared especially
often and where they spent the greatest amount of time. It is precisely
here that regularly repeated routes and constant tracks are concentrated,
while these are more distinctly expressed in the case of males than for females.
Even the core area of the territory is utilized unequally, or selectively,
by tigers: seldom visited or almost unvisited sites remain here. In the
case of the "Emperor" tiger, such sites include, for example, the axial part
of the divide between Bogdanov and Kolonkovyi Streams and the mountain slopes,
encircling the upper reaches of Kammenyi Stream.
The inequality in the utilization of the territory abruptly increases from
the core of the territory to its periphery. The latter does not present
itself as some sort of integral zone spanning the core area. The more distant
travels of tigers are not oriented outward from the core in all possible
directions, but rather only in certain directions. These journeys often
serve, in both their direction and character, as direct continuations of
routes that cross the center of the territory. The differentiation between
the core and the periphery of the territories is generally accomplished primarily
according to the tigers' frequency of visitation of them. Thus, in the winter
of 1971-1972, the male "Emperor" tiger walked across the upper reaches of
Bol'shoi Stream (Orekhovka River basin) five times, but he visited the narrow
side valleys of Igristyi and Sobolikha Streams only once in the case of each
valley.
The lowest degree of orderliness distinguishes the routes of the second male
that we had under observation (the "Lazy" tiger), which provides a basis
for considering this tiger as non-territorial (i.e., as nomadic).
His numerous repetitions of routes along the roads in the valleys of Bol'shoi
Stream and the Gornaya River, which, it might be thought, contradict such
a conclusion, followed each other in series without any sort of intervals
between them.
According to the data that we have analyzed, territories of individual animals
do not have clear-cut external outlines. Their boundaries cannot be expressed
as straight lines in even a rough, schematic form. Changes in the intensity
of the use of territories, as traced from the core of the territory to its
periphery, are very gradual. Moreover, the system of routes for each animal
acquires new features from year to year. The possibility of the existence
of linear borders is generally doubtful. In any case, situations, in some
degree corresponding to our ideas about them, can be fitted only locally
within defined "narrow" sites on the periphery of the territories (on the
territory of the "Emperor" tiger, this was observed, for example, on the
mountain slopes of the right bank of the Gornaya River).