Aspects of Human Settlement
An ecosystem includes not only the biological components
of a particular environment, like plant and animal species, but
also abiotic (nonliving) processes, like nutrient and energy cycles. The health of all species living in the
Yellowstone area depends on the proper functioning of these processes.
It is hard to define the boundaries of any ecosystem. An ecosystem can be as small as a forest
patch, or as large as the entire planet.
For management purposes, however, the National Park Service
and the United States Forest Service have designated 18 million
acres of land in Idaho, Montana, and Wyoming, as the “Greater Yellowstone
Ecosystem” (GYE). These lands include not only the national
park itself, but also surrounding areas that provide critical habitat
for wildlife species, or support important ecological processes,
such as portions of the region’s many river systems. For more information about the Greater
Yellowstone Ecosystem, please refer to the Greater Yellowstone Coalition’s web
Nineteen percent of land in the GYE
is privately owned. Some
of these areas are already facing rapid exurban development, especially
around Jackson, Wyoming and in the so-called “Paradise Valley” south
of Livingston, Montana. Most of the private landholdings in the
GYE are located in prime low-elevation habitat such as river valleys
and the surrounding wetlands (Hansen and Rotella 2000). These areas have a more equitable climate
and higher primary productivity than the surrounding uplands, and
thus are preferred habitat for many wildlife
species (Hansen and Rotella 2000).
Over 1 million acres of rangeland in the GYE was subdivided
into smaller “ranchette” parcels as of 1990 (Witkowsy and Lawlor
1995). These developments not only introduce
humans and potentially predatory pets into areas previously disturbed
only by grazing livestock, but they necessitate the construction
of roads. Roads pose numerous threats to wildlife,
including acting as “filters” which only some species are able or
willing to cross, as invasion corridors for exotic species, and
heighten the chances that an animal will be run down by a car or
truck (Theobald et al 1996). Roads also cause polluted runoff to enter
nearby rivers, lakes, and streams, degrading habitat even further.
Because private lands in the GYE are widely dispersed,
there is a large interface between the public and private holdings,
and thus a high potential for conflict between individual citizens
and government agencies. One of the most volatile issues is how
to manage natural disturbances like fires and floods. The GYE is an arid area, and fire was
historically a very important ecological process here. Frequent fires maintained the region’s
grasslands and lodgepole pine forests, and local animal species
(like grazing bison) evolved to live in these habitats.
Although fires were suppressed in the national park in the
early part of this century, the recent policy of the National Park
Service is to let fires burn naturally (Knight 1991).
However, fires here are usually initiated in the dry, valley-bottom
grasslands, where most of the exurban development has taken place,
and thus are extinguished by residents or local fire departments
before they have a chance to spread into the publicly owned upland
areas (Hansen and Rotella 2000). This change
in the fire regime has the potential to affect plant communities,
and the animal species that live in them, on a large scale.
In recent years, many conflicts have centered on
controlling floods on the Yellowstone River. The “Paradise Valley”
of the Upper Yellowstone River is one of the fastest growing regions
of Montana, and people want to live along the beautiful riverbank.
Unfortunately, they are not willing to face the consequences
of living near a large and unpredictable river. At 670 miles, the
Yellowstone is the longest undammed river in the lower 48 states,
but it is far from free-flowing.
In 1996 and 1997,
“100 year” floods hit the Yellowstone
two years in a row (Kesselheim 2000).
During the following two years,
the Army Corps of Engineers issued 82 permits for Yellowstone River
flood control projects in Park County (Kesselheim 2000).
Most of these projects called for the
installation of “riprap” – stones or concrete blocks laid along
the riverbank to prevent erosion (Kesselheim 2000).
These projects went ahead despite warnings from the Fish
and Wildlife Service that the riprap and levees could threaten trout
In May, 1999, six Montana conservation
groups sued the Army Corps of Engineers for failing to consider
the cumulative impacts of river armoring on fish and wildlife habitat
and hydrological processes (see www.greateryellowstone.org/yellowstone_river_news.html
for more details).
May, 2000, a judge ruled against the Corps, but the effects of this
ruling are uncertain.
proponents of flood control are wealthy and politically powerful,
like the owners of the famous fishing streams called “spring streams”
which flow into the Yellowstone.
These landowners are well represented
on Governor Marc Racicot’s Upper Yellowstone River Task Force, and
conservation groups worry that the group may oppose scientific
monitoring of the area
Hansen, Andrew J. and Jay J. Rotella. 2000. Nature reserves and land use: implications
In Applying Ecological Principles to Land Management,
Dale and Haeuber. New
York: Springer New York.
Kesselheim, Alan S.
2000. The last
wild river. Retrieved
April 15, 2001 on the world wide
Knight, Dennis H.
1991. The Yellowstone
fire controversy. In
The Greater Yellowstone
ecosystem: redefining America’s wilderness heritage,
edited by Robert B. Keiter and
Mark S. Boyce. New
Haven: Yale University Press.
Theobald, D. M., H. Gosnell, and W.E.
Riebsame. 1996. Land use and landscape change in the
Colorado mountains II: a case study of the East River valley. Mountain Research and
Development 16: 407-418.
Witkowsky, Kathy and James Lawlor. 1995. Montana under the gun. Planning 61: 4-10.