Greater Yellowstone Ecosystem

The Greater Yellowstone Ecosystem, with Yellowstone at its core, is one of the largest nearly intact temperate zone ecosystems on Earth.

NPS / Jacob Frank

 

The Greater Yellowstone Ecosystem. Description of an ecosystem's size, boundaries, and characteristics can vary greatly.

At 3,437.5 square miles (8,903 km2),Yellowstone National Park forms the core of the Greater Yellowstone Ecosystem—one of the largest nearly intact temperate-zone ecosystems on Earth. Greater Yellowstone’s diversity of natural wealth includes hydrothermal features, wildlife, vegetation, lakes, and geologic wonders like the Grand Canyon of the Yellowstone River.

Heart of an Ecosystem

Yellowstone National Park was established in 1872 primarily to protect geothermal areas that contain about half the world’s active geysers. At that time, the natural state of the park was largely taken for granted. As development throughout the West increased, the 2.2 million acres (8,903 km2) of habitat that now compose Yellowstone National Park became an important sanctuary for the largest concentration of wildlife in the lower 48 states.

The abundance and distribution of these animal species depend on their interactions with each other and on the quality of their habitats, which in turn is the result of thousands of years of volcanic activity, forest fires, changes in climate, and more recent natural and human influences. Most of the park is above 7,500 feet (2,286 m) in elevation and underlain by volcanic bedrock. The terrain is covered with snow for much of the year and supports forests dominated by lodgepole pine and interspersed with alpine meadows. Sagebrush steppe and grasslands on the park’s lower-elevation ranges provide essential winter forage for elk, bison, and bighorn sheep.

 

Space and Ownership

• 12–22 million acres; 18,750–34,375 square miles (Sizes, boundaries, and descriptions of any ecosystem can vary.)
• States: Wyoming, Montana, Idaho
• Encompasses state lands, two national parks, portions of five national forests, three national wildlife refuges, Bureau of Land Management holdings, private and tribal lands.
• Managed by state, federal, and tribal governments, and private individuals

Wildlife

• One of the largest elk herds in North America
• Largest free-roaming, wild herd of bison in United States
• One of few grizzly populations in contiguous United States
• Rare wolverine and lynx sightings

Management Challenges

• Climate change
• Invasive species
• Managing an ecosystem across political boundaries
• Land use change
• Conservation of migration corridors 
• Increasing visitation 
• Wildlife diseases
• In Yellowstone:

  – Bison management
  – Grizzly bear management
  – Native fish conservation
  – High Visitation

 

Influence of Geology

Geological characteristics form the foundation of an ecosystem.

Air Quality

Yellowstone National Park is a Class I airshed. The largest source of particulate matter in Greater Yellowstone is smoke from wildland fire.

Soundscapes

Sounds have an important ecological function for reproduction and survival. Together they form a soundscape.

Water

Learn about the role of water in Yellowstone and beyond.

Cycles and Processes

Many animals migrate seasonally, following the new growth of grasses and other food sources.

Winter Ecology

Winter in Yellowstone is a place of magic and vulnerability.

Beyond Boundaries

Managers from local, state, and federal agencies across the Greater Yellowstone Ecosystem coordinate efforts around resource issues.

Land Use

How land is used outside the park can disrupt ecological processes within the park.

Wilderness

More than 2 million acres of Yellowstone are recommended for federal wilderness designation and managed as such.

Winter Use

The winter use debate spans more than 80 years, with each participant asking: should the park be accessible in winter?

Nature

Discover the natural wonder of Yellowstone and our role in the conservation of wildlife.