Yellowstone rangers seeking information about a man who helped a bison calf get out of the Lamar River/Hellen Jack via NPS

Yellowstone National Park rangers are seeking a man who tried to help a bison calf that became separated from its mother while crossing the Lamar River, an incident that led rangers to put down the calf because it was abandoned by the herd.

The incident Monday evening was somewhat reminiscent of an incident seven years ago when a Canadian visitor loaded a bison calf into his SUV and took it to the Buffalo Ranch in the park because he was worried it would be hit by a vehicle.

In this case, park staff say an unidentified white male in his 40s-50s, 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, a park release sent Tuesday said. Visitors later observed the calf walk up to and follow cars and people.

Yellowstone staff said human interference "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."

In the 2016 incident, rangers also had to put the calf down as its mother abandoned it and it "was continually approaching visitors and vehicles."

Approaching wild animals can drastically affect their well-being and, in this case, their survival. Park regulations require that 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, you're asked to contact the Yellowstone National Park Tip Line at 307-344-2132 or [email protected].