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GRTE-N-1
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Research Report GRTE-N-1
The Elk of Grand Teton and Southern Yellowstone National Parks
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THE ELK POPULATION
The elk that winter on lands within the Jackson Hole, Buffalo River,
and Gros Ventre River valleys are collectively called the Jackson Hole
herd. A division of this herd into its north and south segments, major
winter herds, summer segments and groups is shown in Table 3. The elk
that summer in Grand Teton and southern Yellowstone Parks are shown to
be part of the refuge winter herd as well as the northern herd.
The period before the winter of 1955-56 is considered the past; since
this date, the present. Comparisons of past and present numbers that
start from the fur trade period could only be made by using records for
the entire Jackson Hole herd. Records of elk numbers on and adjacent to
the area that became the National Elk Refuge start from the winter of
1911-12.
Table 3.Division of Jackson Hole Elk Herd into major population
segments, winter herds, summer segments and groups
Major population segments |
Winter herds |
Summer herd segments |
Summer groups |
Migratory segments |
NORTHERN HERD |
Refuge |
Refuge |
Valley |
Nonmigratory |
Grand Teton Park |
Valley
Mountain |
Grand Teton |
Southern Yellowstone Park |
Pitchstone Plateau
Central Mountain
Two Ocean Plateau |
North |
Teton National Forest |
Glade Creek
Pilgrim Creek
Pacific Creek
Ditch Creek
Sheep Mountain |
Gros Ventre |
Two Ocean Plateau
Buffalo Fork
Gros Ventre |
Gros Ventre |
SOUTHERN HERD |
South Park-Hoback |
Hoback
Lower Snake |
South |
Jackson Hole Herd
Numbers
Records before 1900 are limited to general narrative accounts.
Osborne Russell kept a detailed journal on his trips through the Jackson
Hole and Yellowstone areas during 1834 and 1843 (Haines, 1965). In the
Jackson Hole area during July he made such comments as: "This valley,
like all other parts of the country, abounds with game." and "Game is
plenty and the river and lake abounds with fish." He specifically
reported that the valley on the west side of the Teton Range ". . .
abounds with Buffalo Elk Deer antelope etc. . . ." Reports of killing
these animals for food were made by Russell and others traveling through
the Jackson Hole area. In the Yellowstone Lake area during August,
Russell wrote ". . . we found the whole country swarming with Elk . . ."
Other general summer observations of abundant elk and other wildlife in
southern Yellowstone from 1870 through 1876 expedition reports have been
reviewed by Murie (1940). These strongly refudiate opinions that elk and
other wildlife were originally scarce in the mountains. Sheldon (1927)
cited an 1887 account of a Jackson Hole trapper reporting that 15,000
elk wintered in the valleys of the Shoshone and Snake. This should
probably read Shoshone or Snake. Evermann (1892) reports that early maps
labeled the Snake River as the Shoshone. A presettlement account of elk
wintering along the Snake River bottoms in the 1870's with greater
numbers near the south end of the Jackson Hole valley is related by
Murie (1951).
Records of elk numbers between 1900 and 1910 are mainly from
estimates by Nowlin (1904 and 1909) and Preble (1911). These varied from
20,000 to 25,000 animals. Kneipp (1915) used a partial ground count of
over 13,500 animals to estimate that at least 17,000 elk were present
during the winter of 1911-12.
Records of numbers in winter herds from 1915-16 on are from periodic
ground and/or aerial counts (after 1927). Ground counts were made by
crews of Federal agency and State game commission personnel. A
tabulation of counts obtained over the 40-year period up to the 1955-56
winter is presented by Anderson (1958). An average winter count of about
20,000 elk (19,238 to 22,035) was obtained during five winters within
the first 20-year period from 1915 to 1935. An average of 16,300 elk per
winter (15,014 to 17,902) was counted during six winters within the next
19-year period. An average winter count of about 14,000 elk (11,057 to
17,924) was obtained during six of the winters since 1955-56 (Yorgason,
writ. comm., 1968). The counts since 1955 did not always include
scattered groups off main wintering areas and the actual average may be
slightly higher than shown.
Winter Distributions
A map of Jackson Hole valley wintering areas (Figure 6) shows elk
originally wintered on bottomlands and slopes in the Buffalo River
valley along the east side of the Jackson Hole valley and south from
Ditch Creek through the valley floor into the adjoining Hoback drainage.
Increasing human settlement, agriculture, hunting, and the development
of elk feed grounds progressively changed winter elk distributions after
1910. The proportion of the herd wintering on established feed grounds
increased to about 48 percent by 1935 and 86 percent by 1956 (Anderson,
1958).
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Fig. 6. Boundaries of historical
elk winter range showing the main portion of Jackson Hole valley lands
(shaded) where the animals are excluded because of human settlement or
conflicts with agriculture. (click on image for an enlargement in a
new window) |
Small bands of elk still use historical winter ranges north of Ditch
Creek (Figure 6). South of this creek the greater portion of the herd
now winters on or adjacent to feed grounds within the National Elk
Refuge or other State feed grounds scattered through the south half of
the Jackson Hole valley. The present Gros Ventre herd winters within the
area mapped as their original range, but livestock grazing occurs on
bottomlands and some slopes.
Relations to Green River Herd
Most literature on the Jackson Hole area relates a confusing story on
the relationships between the Jackson Hole and the Green River elk
herds. A review of this literature suggested how this may have occurred.
Preble (1911) begins his report by stating that "Jackson Hole has long
been the principal winter range for large numbers of elk." He later
wrote, "In former years, large numbers, possibly the great majority of
those that summer in the high ranges of northwestern Wyoming, wintered
in the Red Desert." Graves and Nelson (1919) were probably influenced by
this general statement when they reported, without supporting evidence,
that "In early days elk passed through Jackson Valley to the plains
beyond," Sheldon (1927) also did not present sources or evidence for his
statement that: "Formerly herds of elk from the southern part of
Yellowstone National Park . . . passed Jackson on their autumn migration
and wintered in the Green River basin."
From this point on, a series of writers refer to some of this early
literature as establishing that elk originally migrated through the
Jackson Hole area to the Green River basin (Allred, 1950; Murie, 1951;
Craighead, 1952; Anderson, 1958), Supporting evidence for this migration
is limited to observations of elk trails crossing divide areas between
the Gros Ventre, Hoback, and Green River drainages and reports of large
numbers of elk wintering in the Green River basin during the 1880's.
Market hunting and starvation were reported to have greatly reduced the
Green River winter herd by about 1913.
Barnes (1912) appears to be the first to specifically report that
there were distinct Jackson Hole and Green River winter herds. This was
based upon interviews with local Forest Service personnel and field
observations. Brown (1947) reviewed some of the early literature and
states that the "Green River migration (from Jackson Hole) is not
established beyond dispute." Craighead (1952) and Anderson (1958)
considered it unlikely that large numbers of Jackson Hole elk would
suddenly cease to migrate because of settlement and hunting pressure in
the distant Green River basin.
The confusion undoubtedly results from early unsupported statements
being accepted as facts and some writers not being aware that summer
segments from different winter herds may intermingle across drainage
divides. It is this writer's judgment that summer herd segments from the
Jackson Hole and Green River winter herds were intermingled on both
sides of mountain divides between the Hoback, Gros Ventre, and Green
River drainages. Except for minor interchanges, the animals returned to
their respective wintering areas. This migration and intermingling
pattern occurs between animals from at least six different winter herds
in southern Yellowstone Park today (see Intermingling between
Herds.)
Past confusion concerning the relationships between the Jackson Hole
and Green River herds has led to a general belief that Jackson Hole
areas were not natural or historical winter ranges for any appreciable
numbers of elk. It has also been suggested that the elk may have
migrated out of Jackson Hole areas to a greater extent during severe
winters. This would be difficult because mountain passes out of Jackson
Hole would usually be blocked by the time snow depths finally force
large numbers of elk into the valley. Migrations in anticipation of
severe winters would be unlikely.
The 1887 to 1911 estimates of 15,000 to 25,000 elk in the Jackson
Hole herd, with highest numbers reported during severe winters, should
establish that the Jackson Hole and Gros Ventre valleys were historical
winter areas. The first organized censuses, which accounted for
approximately 20,000 animals, also seem to confirm that large numbers of
elk were present historically.
Refuge Winter Herd
The average winter count of this herd was about 7,500 elk (4,233 to
9,804) during 13 of the winters from 1912 to 1954 (Anderson, 1958). An
average of about 7,200 (5,746 to 11,017) was counted during 11 winters
from 1955-56 to 1966-67 (Yorgason, writ. comm., 1968). Figure 7 shows
the estimated summer distribution of elk from the refuge winter herd
during 1964. The 1963-64 winter herd of approximately 8,000 animals was
assumed to increase by 23 percent and number about 9,800 during the
summer.
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Fig. 7. Summer elk distribution
by area and track count transects (|---|). Burnt Ridge, 1; Snake River,
2; Pacific Creek, 3; Buffalo River, 4; Park Boundary, 5; Blackrock, 6;
Four Mile Meadow, 7; Togwotee Pass, 8. (click on image for an enlargement in a
new window) |
Distribution estimates for south Yellowstone Park and adjoining
Forest Service areas were primarily from counts of elk tracks crossing a
45-mile migration route transect. Migration trails in the snow were
backtracked from an airplane to determine animal origins. Relative
distributions within portions of the area were projected from repeated
summer ground or aerial counts on sample areas.
Distribution estimates for Grand Teton mountain areas were obtained
from track counts during fall migrations or as projections from ground,
aerial, or photoelectric eye counts (on migration trails) within sample
areas. Martinka (1965) obtained estimates for Grand Teton and refuge
valley areas from ground counts and calculations that used sex and age
or marked to unmarked animal ratios.
The estimates of 200 and 250 elk for Forest Service lands off the
northeast corner of Grand Teton and the east side of the refuge were
arbitrarily assigned. Repeated ground and aerial observations indicated
that comparatively few elk summered in this area. The estimate of 400
elk for the Forest Service area east of Grand Teton was obtained from
ground and aerial observations.
The estimation methods applied over such an extensive area are
admittedly rough. However, because unusually ideal fall track count
conditions coincided with the greatest observed concentrations of elk on
open subalpine summer ranges in 1964, they were the most complete
measure of distributions obtained during the study.
National Park Elk
Figure 7 shows that about 70 percent of the elk originating from the
refuge winter herd used summer ranges in the two national parks. As will
be shown later, most of the animals migrating to and from the refuge
also traveled over and used Grand Teton lands during spring and fall.
Thus, the refuge winter herd was for the most part a national park herd
during other seasons. This study therefore extended over the seasonal
ranges and migratory routes used by the elk within the area shown on
Figure 1.
Grand Teton
Figure 7 shows about 2,800 elk or 29 percent of the animals
originating from the refuge winter herd summered on Grand Teton in 1964.
About half of these summered on valley lands. Other elk from the refuge
moved onto Grand Teton lands in late summer. Martinka's (1965) estimates
of summer numbers in refuge and Grand Teton valley herds for 1963 and
1964 with subsequent estimates by the author and Houston (1968) are
shown in Table 4. The comparatively low numbers in valley herds during
1965 and 1966 appeared to result from local shifts of elk in response to
high levels of disturbance associated with a forest insect control
program (Cole, 1966 and 1967).
Table 4.Maximum late July or early August counts of elk on
refuge and Grand Teton valley areas with calculations of probable numbers.
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Year |
Refuge Maximum count |
Grand Teton Valley |
Maximum count | Probable number |
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1963 | 365 | 643 | 1,4301 |
1964 | 346 | 632 | 1,400 |
1965 | 119 | 371 | 8201 |
1966 | 101 | 401 | 8901 |
1967 | 233 | 513 | 1,1401 |
1 Expanded using 1964 marked animal and sex ratio data (Martinka, 1965)
that showed about 45 percent of the Grand Teton Valley Herd was observed
by direct maximum counts.
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Osborne Russell's accounts from his 1834-1843 trips (Haines, 1965)
suggest that appreciable numbers of elk originally summered in Jackson
Hole valley areas. Between 1900 and about 1960, persons reporting on elk
distributions either failed to mention valley summer herds in Grand
Teton or stated that only small groups were present. McLaren (1966 pers.
comm.), who has been a park ranger in Grand Teton since 1952, reported
that he first noticed large groups of 100 or more elk summering in the
park in 1960. An August 1962 aerial flight which only sampled valley
areas accounted for 595 animals. A later October flight, which caught
over 2,500 elk in the process of migrating from Grand Teton areas to the
refuge, established that large numbers of elk were summering within the
park and led to studies on valley and mountain herd segments.
Southern Yellowstone
Figure 7 shows about 4,100 elk, or 42 percent of the animals
originating from the refuge winter herd, summered in southern
Yellowstone. Preble (1911) estimated that approximately 4,000 summered
in this region. The southern Yellowstone area shown to contain an
estimated 2,500 elk in 1964 was the remote central mountain region where
the greatest concentrations of summering elk were observed. It was
chosen for intensive study because it appeared to afford the best
opportunity to assess the effects of large numbers of elk on high
elevation summer ranges.
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