"I saw the baby bison that tourists tried to rescue. Here’s what you don’t know about the story."
The orphaned calf in early May, days before tourists tried to rescue it. The calf remained near this spot, about 35 yards from the road, and soon it began approaching vehicles in the same area. (Deby Dixon)
https://www.washingtonpost.com/news/animalia/wp/2016/06/07/i-saw-the-baby-bison-that-tourists-tried-to-rescue-heres-what-you-dont-know-about-the-story/
Every year in Lamar Valley, we see bison calves by themselves, destined to perish. Their mothers might have died in childbirth, abandoned them or become separated during a river crossing. We watch as the calf runs from cow to cow, looking for its mother. We watch the other cows react with violence, particularly if the calf attempts to nurse. A wild bison cow will not adopt another’s calf. I have seen calves take up with bulls, which sometimes tolerate them. But eventually the calves are too weak to keep up during the daily roaming and are most likely captured by a coyote, wolf or bear.
Earlier this year, I watched a young calf run from herd to herd while a coyote followed behind. The calf did not seem to know that the coyote presented danger and ran right up to it and sniffed its nose. This was a tragic sight to watch: A healthy calf expending so much energy to find a home, and that coyote, always close behind. Before long, calf and coyote disappeared down the hill and onto the valley floor. To my knowledge, the calf was never seen again.
(snip)
The park service, apparently not realizing that the calf had been abandoned or orphaned for several days, attempted to return it to Lamar Valley, but there was no mother waiting for her baby. Rather than let people stand by and watch this creature perish or be killed, or cause an accident by running into the road, the park service ended the calf’s life. If you are in Yellowstone long enough to see animals suffer and die, you will know that when all was said and done, this was a kind ending for the calf that took a ride in a car.
= new reply since forum marked as read
... then leave the carcass for scavengers. 
We certainly interact with nature, and indeed depend on it, to such a degree that finding the seam between humans and the rest of nature is an increasingly difficult task. "Management" is increasingly unavoidable, if for no other reason than to clean up our own mistakes vis-a-vis "nature."
Some here condemn "trophy hunting," when programs like Quality Deer Management, now widely-practiced on both public and private lands, have introduced Antler Restrictions to promote better herd balance and sustainability. In short, QDM REQUIRES a hunter to take only bucks which have good or better antler growth. Times were when Any buck was legal which resulted in gross distortions in a region's deer herds: Most all young bucks start with only a few short tines, so who knows if one never develops a good "rack," and remains a genetically-inferior animal, or if one becomes a real trophy with large antlers? I now pass up young bucks with "forks," or decent but clearly small racks. I have taken a 10-point whitetail with an17" inside spread, and who weighed 154 lbs on the hoof (big for a low-fence deer in the Texas Hill Country). And what of the lost genetics by killing a big buck? The buck I took was maybe 5.5 yrs old, and for four years had generously spewed his genetics alll over the ranch! 
Think:. Humans in the early 1970s disco scene, too busy even to bathe.
A year or two older, and my buck's breeding days would be over, but he would continue to eat prodigiously of land which can barely sustain huge deer herds. And his once grand antlers would begin to shrink and go gnarly.
