Yellowstone National Park officials made a difficult decision to kill a baby bison after a visitor helped the animal cross a river, but its herd rejected the calf.

According to NBC News, Yellowstone said in a press release that the calf had been separated from its mother when the herd crossed the Lamar River in the park's northern section in Wyoming on Saturday.

As he saw the newborn bison struggle to cross the river, the park visitor intervened by pushing the animal from the river and onto a roadway. Visitors then reported seeing the calf walk up and approach cars and humans.

The statement said park rangers repeatedly tried to reunite the animal with the herd. However, those efforts failed as human interference can cause wildlife to reject their offspring. 

The release noted that the park staff had to euthanize the baby bison after the failed reunification efforts because "it was abandoned by the herd and causing a hazardous situation by approaching cars and people along the roadway."

"We made the choice we did because national parks preserve natural processes," Yellowstone National Park officials said in the statement.

Responding to questions about why the baby bison was not sent to a sanctuary or zoo, the park tweeted that "this is a conversation that is difficult to have on social media." 

The park's website has a section explaining why it does not rescue animals after they become separated from their mothers or are injured.

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Yellowstone National Park Visitor to Face Charges If Found Guilty

Officials at Yellowstone National Park said the park regulations require visitors to stay at least 25 yards from bison, elk, and deer and 100 yards from bears and wolves.

They noted that approaching these wild animals can affect their well-being and survival. In the press release, the park also released an image of the man who lifted the calf from the river.

CNN reported that if the unidentified visitor was found guilty of any wrongdoing, he could be charged with a Class B misdemeanor, facing up to six months in jail and a $5,000 fine.

Yellowstone National Park told the outlet that the charge would include approaching and disturbing wildlife and disorderly conduct. The park has established a tip line in connection with its investigation and urged anyone in the area on May 20 to call here for any information.

This incident is not an isolated occurrence. At least three incidents occurred in May and June last year when three park visitors interacted with bison and were injured severely.

In one instance, a 71-year-old woman was attacked and gored by a bison a day after a different calf hurt another visitor.

Why Did the Herd Reject the Baby Bison?

According to Dr. Jeff Martin, director of South Dakota State University's Center of Excellence for Bison Studies, humans have historically been bison's primary predators, shaping their behavior towards human interaction. 

The bison's keen sense of smell allows them to detect the odor of a human on a calf's fur, leading them to reject the calf as a potential threat, KELOLAND reported.

Martin explained that bison are naturally wary of humans and prioritize the entire herd's safety. Despite their seemingly calm demeanor, he said bison are still wild animals and one of "the largest land mammals on this continent."

Martin noted that bulls can weigh up to a ton or 1,000 kilos, while calves can weigh up to 500 kilos. He reminded visitors of national and state parks to always remember that these wild animals are not domesticated and should be treated cautiously.

He warned against intervening or approaching them, especially without proper training, as such actions can be dangerous for humans as well as animals.

For example, he said interfering between a mother and her calf could provoke an aggressive response from the mother.

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This article is owned by Latin Post.

Written by: Bert Hoover

WATCH: YNP Officials Search for Man Who Disturbed Bison Calf Resulting in its Death - From NBC Montana