History of Wolves

Gallatin County is often viewed as a basecamp to Yellowstone, attracting thousands of park
tourists each year. Visitors worldwide flock to the Greater Yellowstone area to view the
park’s bubbling pools, scenic trails, active geysers, and roaming wildlife. Park visitors may
be fortunate enough to observe the spectacular wildlife throughout the park. However, few
visitors are familiar with the fascinating history of one animal that helped shape the
Greater Yellowstone Ecosystem: wolves.

Gray wolves were nearly hunted to extinction in the 1920s, with the final wolf in
Yellowstone National Park eradicated by 1926. The removal of gray wolves within the park
fostered unexpected changes throughout the ecosystem and landscape. Lack of predation
from wolves led to escalated elk and deer populations. Elk and deer munched on aspens
and willows with reduced vegetation from overgrazing. Subsequently, bird populations
began to dwindle as their habitat was minimized. Not only did the absence of this
vegetation affect wildlife, but the banks of the rivers also began to erode from the lack of
plant stabilization. Countless adverse effects occurred throughout the park. Yellowstone
experienced a significant adverse chain reaction due to the removal of the ecosystem’s
apex predator.

In 1987, the U.S Fish and Wildlife Service proposed reintroducing an “experimental
population” of wolves into the park. This controversial proposal was finally accepted in
1995. 31 gray wolves from Western Canada were relocated to Yellowstone by the Fish and
Wildlife Service. Remarkable and lasting impacts were felt within the park due to this
crucial predator’s reintroduction.

Initial Impacts

Wolves began to prey on elk, coyotes, deer, and other small mammals. This predation, in
turn, helped regulate the over-grazing and allowed previously degraded vegetation to grow.
The massive elk population was forced to migrate and browse less intensely due to strain
from wolf predation. Willows, cottonwoods, and other plant species flourished, supporting
grazing animals with a more reliable food source.
Countless animal populations rose due to beneficial changes in their healing environment.
While wolves preyed on coyotes, mouse and rabbit populations skyrocketed, bringing more
hawks and bald eagles to the area. These scavengers also had an abundance of remains to
pick from after wolves began hunting coyotes. Bears benefited from leftovers of the wolf
kills as well. Moreover, the healthier wolf population began to pursue more elk, which
improved balance and equilibrium throughout the food chain.

Changing Geography
Tree growth increased tremendously, which provided stability in the soil and along river
banks. The stability of the trees reduced the amount of soil erosion. Less erosion along the
river caused small pools to form, generating habitat for wildlife. River channels also
deepened and began to meander less over time, becoming more fixed in their course.
The incredible history of these beasts demonstrates how connected and dependent species
in this area are to one another. As of 2021, around 90 wolves were documented in the park.
This population has declined substantially in the past 15 years. Wolves are managed by the
appropriate agency in each state surrounding the park. Wolves are fully protected within
park boundaries. Outside of the park, the hunting of wolves is regulated by specific
agencies. For more information about current regulations regarding the protection of these
creatures, visit fws.gov.