MAMMOTH HOT SPRINGS, Wyoming — Yellowstone National Park rangers are seeking information about an incident that indirectly led to the death of a bison calf.

Park officials say on Saturday, May 20, an unidentified man in his 40s or 50s, wearing a blue shirt and black pants, approached a newborn bison calf in the Lamar Valley near the confluence of the Lamar River and Soda Butte Creek in the northeast corner of the park.

The calf had been separated from its mother when the herd crossed the Lamar River, according to a news release. Park rangers say 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.

This is not the first time a bison calf was killed after interacting with humans. In 2016, several tourists put a bison calf inside their vehicle and transported it to a park facility after concern about its wellbeing. The calf had to be killed in that situation as well. Read more about that incident here.

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Park rangers warn approaching wild animals can drastically affect their well-being and, in this case, their survival. Park regulations require people stay at least 25 yards away from all wildlife (including bison, elk and deer) and at least 100 yards 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.

Rangers are asking anyone that was in the Lamar Valley on the evening of May 20, and has information that could help this investigation, to contact the Yellowstone National Park Tip Line at (307) 344-2132 or YELL_Tip@nps.gov.