Read Specifically about: Bison,
|The National Elk Refuge (NER) and Grand Teton National Park (GTNP)
are adjacent to one
another and are located just north of Jackson, Wyoming. They are situated at the southern end of
the Greater Yellowstone Ecosystem. The NER is approximately 25,000 acres and GTNP is about
304,000 acres. The elk and bison that inhabit the NER and GTNP are part of the Jackson elk and
bison herds, which comprise one of the largest concentrations of free-ranging elk and bison in
North America—approximately 13,000 elk and 1,000 bison. The Jackson elk and bison herds
migrate across several jurisdictional boundaries including the NER, GTNP, Yellowstone National
Park, Bridger-Teton National Forest, Bureau of Land Management resource areas, and state and
private lands. Because of the wide range of authorities and interests, the FWS and NPS are
seeking a cooperative approach to management planning involving all of the associated federal
and state agencies and a broad range of organized and private interests.
|The need to begin managing the Jackson bison population is to address
the increased competition
between bison and elk and other wildlife for forage, and the increased risk of habitat degradation,
disease transmission, and property damage resulting from a rapidly growing bison population.
These concerns have resulted from the following factors.
The once fenced (1948 - 1968), then free-ranging and naturally regulated
(1969 - 1980) Jackson
Increased competition with elk and other wildlife for forage and increased
As a result of a lawsuit filed in 1998, the court ordered that no destruction of bison occur on the NER or GTNP for population control purposes until the FWS and NPS analyze bison management in combination with the winter feeding program. The court further ordered that NEPA analysis of the winter feeding program be conducted.
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|Winter feeding of elk, which began in 1910 in Jackson Hole, was originally
initiated to reduce
winter mortality of elk, thereby avoiding marked reductions in a population of animals important
to local residents and interest groups, as well as to minimize depredation of ranchers’ hay.
Although these immediate factors prompted the initiation of winter feeding, the need for the
NER’s winter feeding program can be traced back to reduced access to significant parts of their
native winter range. Historically, elk that summered in the area now inhabited by the “Jackson elk
herd” wintered in the southern portion of Jackson Hole (present location of the NER and the
town of Jackson) and areas outside of Jackson Hole, including the Green River and Wind River
basins to the south and east, respectively, and the Snake River basin to the southwest in what is
now eastern Idaho. Migration to these wintering areas probably varied significantly from year to year but little actual evidence remains to document that process. Migrations to these wintering areas, except to southern Jackson Hole, were eventually abandoned due to settlement and other human activities outside of the Jackson Hole area.
Because of the considerable amount of snow that can accumulate in Jackson
Hole in winter,
The winter feeding program on the NER has allowed the Jackson elk herd
to be sustained at a
The feeding of elk on the NER has not come without cost, however.
Nearly 100 years of
The removal of the natural effects of harsh winters (i.e. "winter kill") on the elk population, and the difficulty in reaching adequate harvest quotas through hunting have made it difficult for managers to maintain optimum population size. If natural herd mortality effects of weather are continually displaced through winter feeding, more effective hunting programs will likely be necessary to maintain the Jackson elk herd within the summer carrying capacity of its available range.
A potential influence on this situation may come from increased elk predation - loss to wolves, bears, and mountain lions. As predator numbers increase, it is likely their effects on elk population size may eventually become significantly additive to the harvest reduction. Though estimates of maximum predator population sizes and predation rates have been developed through modeling, it is critical to monitor this situation over time to thoroughly understand the combined effects of predation and harvest on the elk population.
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