Yellowstone's Northern Range - Greater Yellowstone Science ...

THE NORTHERN RANGE
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activity (95 percent) occurs in confined escape
terrain (steep cliffs) or areas within 1,000 feet of
that terrain confirms observations of others (Figure
7.12) (Oldemeyer et al. 1971, Van Dyke et al.
1983). Elk or bison are rarely found in the kind of
escape telTain defined by Smith (1991). Interspecific
diet data, then, has limited usefulness in
interpreting competition unless the terrain that the
diet items were obtained from in has been factored
into the equation.
RESEARCH
RECOMMENDATIONS:
BIGHORN SHEEP
Even with previous studies of Yellowstone's
bighorns, and with information made available
from other populations in the west, we lack basic
information on bighorn sheep: 1) the seasonal
movements and habitat use of wild sheep, factors
limiting their population growth, and interchange
with other sheep populations in the Gallatin­
Absaroka-Beartooth Mountains; 2) as docile as
bighorns appear to the public in the park, we still
have no definitive data on the effects of people,
trails, and roads on their well-being; and finally 3)
it is vital that we determine the effects of introduced
domestic cattle and sheep diseases tlley are
frequently exposed to on their winter and summer
ranges to determine if that factor is significant in
the well-being of the bighorn sheep. A new study
beginning in 1997 will contribute to our understanding
of the first two items (L. Irby, Montana
State Univ., pers. commun.)
WHITE-TAILED DEER
Many observers have used Skinner's (1929)
repOlt of a decline in white-tailed deer numbers to
suggest that the white-tailed deer were a casualty
of elk overpopulation (Chase 1986, Wagner et al.
1995a). Historical records, however, suggest that
Skinner'S reported population of 100 white-tailed
deer on the northern range around 1890 was a
short-term increase in the presence of that species
(Houston 1982). Schullery and Whittlesey (1992),
in their analysis of 168 pre-1882 accounts of
Yellowstone National Park-area wildlife, found ten
statements about the presence (unspecified
location) of white-tailed deer (in the entire park
and surrounding area), but only one actual sighting
of white-tailed deer in the park, and concluded that
white-tailed deer appeared "not to have been
common in the park area during the period we
studied." Murie (1940), Barmore (1980), and
Houston (1982) agreed that the park was "the
extreme upper limit of marginal winter range" for
white-tailed deer. Houston (1982), noting that this
increase in white-tailed deer presence in and near
the park around 1900 occurred "in the presence of
very high elk numbers" and in a human-altered
habitat, thought it "unlikely that interspecific
competition with elk for food was the primary
cause of the decline" in their numbers. He suggested
that "a combination of land clearing,
livestock grazing, and human predation outside the
park," along with "fire suppression and artificial
concentrations of elk in the boundary area of the
park," caused the disappearance of this small
group. Others have noted that white-tailed deer
increased around the turn of the century when hay
was being set out for elk and other ungulates. For
these reasons, it does not seem that past alarms
raised about a "decline" in white-tailed deer in the
park were either accurate or justified. Finally it
must be noted that white-tailed deer are not absent
from the park. Rare animal sighting reports
collated by the park in the 1980s and 1990s
continue to show this species as an uncommon
resident of the northern range and an occasional
inhabitant throughout the remainder of the park. It
is interesting that the does are frequently accompanied
by fawns.
RESEARCH
RECOMMENDATIONS:
WHITE-TAILED DEER
It is recommended the park continue to
monitor white-tailed deer as it has for many years
using the "Rare Animal Observation Monitoring
System." Given the low numbers of the species in
the park, yet the robust popUlations in other parts
of the greater Yellowstone ecosystem, especially its