It's been 16 months now since Rocky Mountain elk wearing radio telemetry
transmitters appeared in Great Basin National Park. So far we have
recorded 82 locations for these elk, providing us with information
on the elk herd's home range, habitat use, population size, and population
growth. This is all critical information needed to properly implement
the White Pine County Elk Management Plan.
The elks' overall home range covers approximately 33,000 acres
of the Weaver Creek, Strawberry Creek and west slope of the south
Snake Range. The park comprises just 22 percent of their home range.
This home range estimate only reflects the main herd found here,
mostly cows, calves and yearlings. Bulls and some yearling cow elk
tend to wander more and can cover extensive area. For example, this
was a banner year for elk sightings. Elk, mostly bulls, were seen
in every major drainage on the east side of the park. We even caught
elk on film (see photo).
The most surprising information we have found is the almost exclusive
use of pinyon, juniper and mahogany habitats. Of 82 locations obtained,
67 locations or 80 percent were found in or adjacent to pinyon and
juniper or mahogany. The remaining locations were in mountain shrub
or mixed conifer habitats. In all cases sagebrush and native bunchgrasses
were either in the understory or nearby. This was expected in the
winter, but not the summer when we thought they would use the higher
elevation aspen and mountain meadows found in the park.
Obtaining the exact number of elk that range in the woodlands on
the south Snake Range is a daunting task. Even with elk wearing
radio telemetry transmitters, seeing every elk as they walk through
a pinyon forest is impossible. Even if they cross an opening, elk
tend to bunch together and that makes it difficult to get an accurate
count. We are using the home range and seasonal distribution information
we gather to develop a strategy to survey for a population estimate.
In the meantime, the highest number we have counted in a single
sighting was 74, and there were more! This number is certainly more
than the 25 estimated to be here in 1999.
Whenever we see the elk we try to get a classification count. In
other words we count them by cow, calf, and bull. By knowing the
number of calves and cow elk we can gauge population growth. So
far we have averaged 41 percent calves in our counts, which indicates
excellent recruitment and a growing herd. By knowing the number
of bulls and cows we can understand the impact of predation on the
herd. So far, the numbers of bulls have averaged 25 percent of cows.
This number indicates that hunting or any other mortality on bulls
is not enough to negatively affect the herd. If bulls were 15 percent
or less of the number of cows this would be considered detrimental
for population health. Elk are definitely here to stay.
Neal Darby is the park's wildlife biologist.
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