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.
Jackson Hole Herd
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.
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).
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.
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.
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).
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.
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.