After an unidentified Yellowstone National Park visitor interfered with a bison calf Saturday attempting to cross the Lamar River, park officials were forced to euthanize the calf.

Now law enforcement officers are asking the public for information about the incident. An unidentified white male in his 40s or 50s, wearing a blue shirt and black pants, approached the newborn calf in the northeast section of the park near Soda Butte Creek. The calf had been separated from its mother when the herd crossed the 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,” said park officials in a Wednesday press release. “The unfortunate incident where the man intentionally disturbed the calf resulted in the death of the calf.”

Interference by people can cause wildlife to reject their offspring. In this case, park rangers tried repeatedly to reunite the calf with the herd, but the 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,” the park said.

Approaching wild animals can drastically affect their well-being and, in this case, their survival. Regulations require people stay at least 25 yards away from all wildlife and at least 100 yards away from large predators. 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,” the park advised.

The death of wildlife is a necessary part of sustaining our populations of predators, scavengers, decomposers and, eventually, herbivores once the nutrient cycle comes full circle, according to park officials. It may be hard to watch the death of an animal, but that is part of the natural cycle of life that helps keep Yellowstone wild.

Every year, hundreds of animals are injured or separated from their mothers or groups for various reasons. Yellowstone preserves one of the largest, temperate-zone ecosystems on Earth, according to a report prepared to answer questions after several social media posts went viral showing the unfortunate deaths of bear cubs and other species after being attacked by predators or injured.

About 99% of the park is managed as wilderness and our focus is on sustaining viable populations of native wildlife species, rather than protecting individual animals, according to the report.

“Animals roam freely on a landscape not dominated by humans. An animal’s survival depends on its own daily decisions and natural selection. Animals with traits that make them better adapted to the environment will tend to survive, reproduce and pass on their genetic characteristics more than animals without those traits. Through this process, natural selection shapes the behavior of wildlife,” it reads.

Actions like feeding, husbandry and rehabilitation contradict the National Park Service mission by shielding animals from the forces of natural selection and creating a zoo-like atmosphere where animals require assistance or protection from people. Rehabilitation itself is a difficult task with an uncertain outcome. These activities are expensive and divert funds that could otherwise be used on more widespread conservation and restoration efforts.

Simply said; in the wilderness of Yellowstone, animals that are vulnerable or make bad decisions become food for others. It is nature’s way.

The National Park Service policy recommends against intervention in natural biological or physical processes except when directed by Congress, in emergencies in which human life and property are at stake, when a park plan has identified the intervention as necessary to protect other park resources, human health and safety, or facilities and to restore natural ecosystem functioning that has been disrupted by past or ongoing human activities.

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