How many wolves were killed in Yellowstone between 1883 and 1917?

Yellowstone National Park is widely celebrated for its remarkable natural beauty and ecological diversity. Among its most iconic species were the gray wolves, apex predators that played a crucial role in maintaining ecological balance. However, the late 19th and early 20th centuries were a period of intense human intervention in Yellowstone’s wildlife populations, particularly targeting wolves. 

Between 1883 and 1917, wolves faced systematic eradication driven by fears of livestock predation, declining game populations, and changing attitudes toward predators. Understanding how many wolves were killed, the authorities responsible, and the broader ecological context provides insight into both the history of wildlife management in the United States and the long-term consequences of predator removal.

Quick Reference: Wolves Killed in Yellowstone (1883–1917)

Time Period	Management Authority	Documented Wolf Killings Inside Yellowstone	Key Notes
1883–1886	Early civilian administration	No reliable records	Recordkeeping was inconsistent; wolf control occurred but was rarely documented in detail
1886–1916	U.S. Army administration	14 wolves (reported total)	Army reports later cited that 14 wolves were officially killed during military management of the park
1915	Early predator control phase	7 wolves	Marks the beginning of systematic, well-documented wolf eradication efforts
1916	National Park Service formed	14 wolves	Predator control intensified as wolves were seen as threats to elk and deer populations
1917	National Park Service	4 wolves	Continued removals under formal NPS predator-control policy
Total (documented minimum)	1883–1917	Approximately 39–45 wolves	Represents only confirmed, recorded kills inside park boundaries

Early Civilian Administration (1883–1886)

During the earliest years of Yellowstone’s management, the park was overseen primarily by civilian administrators. These officials had limited resources, little formal training in wildlife management, and inconsistent enforcement authority. The park had already been subject to incursions by hunters and settlers who viewed wolves as vermin, but recordkeeping during this period was sporadic at best.

Between 1883 and 1886, there is no reliable documentation of wolf killings. Wolves were undoubtedly killed by humans, whether for bounties, sport, or protection of livestock, but official records are largely absent. Anecdotal accounts and historical reconstructions suggest that wolf populations were already under pressure, yet the exact numbers remain unknown. The lack of systematic recordkeeping makes it impossible to determine precise mortality rates for this period. Nevertheless, it is clear that human activity was beginning to significantly impact wolf populations even before formal predator control programs were implemented.

U.S. Army Administration (1886–1916)

In 1886, the U.S. Army was given administrative control over Yellowstone, following widespread problems with poaching, vandalism, and unregulated hunting. The Army’s presence marked a shift toward more structured management, including the beginnings of wildlife regulation. Under the Army, some official records were kept, though they were still incomplete.

Historical reports indicate that at least 14 wolves were documented as killed during the Army administration of Yellowstone. This figure represents a minimum number, as informal killings, unreported incidents, and losses due to unrecorded hunting are not included. The Army targeted wolves primarily because of their perceived threat to elk and deer, which were themselves valued for sport hunting and later, conservation interest. Wolves were considered nuisances that interfered with game populations and sometimes preyed upon livestock in surrounding areas.

The Army’s management policies were paternalistic and utilitarian. Wolves were not yet the focus of comprehensive predator control programs, but the precedent for active removal had been established. This period also laid the groundwork for later, more aggressive eradication efforts that would unfold under the National Park Service.

Early Predator Control Phase (1915)

By 1915, Yellowstone had entered a new era in predator management. Although the National Park Service (NPS) had not yet fully taken control, early predator control initiatives were underway. This period marked the beginning of more systematic and well-documented wolf eradication efforts.

In 1915, 7 wolves were officially recorded as killed inside the park. These killings were part of a deliberate attempt to reduce predation on elk, deer, and other wildlife, which were increasingly valued for hunting and tourism. Wolves were seen as antagonists to human interests, rather than integral components of the ecosystem. The methods employed ranged from shooting to trapping, reflecting a broader societal attitude toward predators as pests to be eliminated.

The killings in 1915 also illustrate the increasing sophistication of wildlife management, in that records were kept with specific dates, locations, and sometimes even the identities of the hunters. This level of documentation represents a shift from the anecdotal and incomplete records of earlier decades.

National Park Service and Intensified Predator Control (1916–1917)

The formation of the National Park Service in 1916 brought formalized management to Yellowstone, including the institutionalization of predator control. Wolves were now explicitly targeted under park policies designed to protect game species and maintain perceived ecological balance.

In 1916, 14 wolves were documented as killed under NPS authority. This marked a significant escalation from prior years, reflecting both the new administrative capacity and a more aggressive stance toward predator removal. Wolves were seen as a threat to elk and deer populations, which were considered vital to the park’s appeal to hunters and tourists. Methods included organized hunting, poisoning, and trapping, all conducted with official sanction.

By 1917, an additional 4 wolves were killed under NPS predator-control policies. Though the number appears smaller than in 1916, it reflects the continuation of a targeted, systematic effort to reduce wolf numbers. These early NPS programs established the precedent for decades of predator management that would eventually lead to the near-extirpation of wolves in Yellowstone by the mid-20th century.

Total Wolves Killed (1883–1917)

Compiling the documented killings from 1883 to 1917, historians estimate that approximately 39 to 45 wolves were confirmed killed inside Yellowstone National Park. This total includes the Army’s documented 14 wolves, the seven from the early predator control phase, the fourteen killed in 1916, and the four in 1917.

It is important to note that this figure represents only confirmed, recorded kills. Many more wolves were likely killed by poachers, settlers, and hunters whose activities went unrecorded. In some years, wolves may have also been driven out of the park, captured, or otherwise removed without formal documentation. Therefore, the true impact of human activity on Yellowstone’s wolf population during this period was likely far greater than the official records suggest.