Yellowstone law enforcement investigate incident of man intentionally disturbing bison calf that results in calf’s death

MAMMOTH HOT SPRINGS, Wyo. (KIFI) – Yellowstone National Park law enforcement officers are asking the public for information about an incident that occurred on the evening of May 20, 2023, between an unidentified man and a newborn bison calf in the park’s northeast corner. The unfortunate incident where the man intentionally disturbed the calf resulted in the death of the calf.

An unidentified white male in his 40-50's, wearing a blue shirt and black pants, approached a newborn bison calf in Lamar Valley near the confluence of the Lamar River and Soda Butte Creek. The calf had been separated from its mother when the herd crossed the Lamar River. As the calf struggled, the man pushed the calf up from the river and onto the roadway. Visitors later observed the calf walk up to and follow cars and people.

Interference by people can cause wildlife to reject their offspring. In this case, park rangers tried repeatedly to reunite the calf with the herd. These efforts failed. The calf was later killed by park staff because it was abandoned by the herd and causing a hazardous situation by approaching cars and people along the roadway.

Approaching wild animals can drastically affect their well-being and, in this case, their survival. Park regulations require people stay at least 25 yards (23 m) away from all wildlife (including bison, elk and deer) and at least 100 yards (91 m) away from bears and wolves. Disregarding these regulations can result in fines, injury and even death. The safety of these animals, as well as human safety, depends on everyone using good judgment and following these simple rules.

If you were in Lamar Valley on the evening of May 20, 2023 and have information that could help this investigation, contact the Yellowstone National Park Tip Line at 307-344-2132 or YELL_Tip@nps.gov.

This incident is under investigation.

Visit a webpage about when Yellowstone staff intervene in a natural process and why for more information.