Yellowstone’s Wonders: Bison Missing Tails

The large bison meandered down the road. We didn’t have much choice but to wait patiently until he moved off the edge of the pavement. No matter. We weren’t rushed on this trip through Yellowstone – our annual Mother’s Day weekend through the Park. Then Mom noticed it. Oh!
“He doesn’t have a tail!”

This was the second tail-less bison we’d seen that day. Only a smooth stub protruded from the point where there is usually a meaty tail with a lengthy whisk reaching to the animals’ hocks. This animal just had an insignificant knob.

“What do you think?” Mom mused. What was the cause of this aberration?

A unique magic exists in Yellowstone Park in May. Life is abundant and full of beginnings. The first flowers dot the meadows while bird song floats through every glen and glade as the migrants return and claim their territory. On a lake still wrapped in ice, we watched an eared grebe floating on the only stretch of open water, his great black crown rising over a tawny flare of ear tufts. Sparks of brilliant white on distant hills marked herds of antelope, and a small group of bighorn sheep grazed peacefully near our lunch stop.

IMG_2504May is when bison calves romp through bright green spring grass, every sight and scent a new discovery. We were gifted with the sight of a bison who had just given birth repeatedly charging a persistent raven looking to grab the afterbirth, even as the red calf wobbled in circles, trying to get a suckle of milk.
The bison seemed especially numerous on this trip. Herds stretched along the road, and on our hikes (for Mom and I can’t be confined to a car for too long), we never went far without encountering more of the burly beasts. After seeing the two stub-tailed bison, we were somewhat obsessed and always looking, wondering: “Are any of them missing their tails?”

We almost asked a ranger about this tail-less bison phenomenon, but he was occupied with bear-jam control. We came up with our own hypotheses: genetics, a manx bison strain; disease, don’t think so; wolves, well probably, but how? Not until later – after a lengthy search with the key words “bison missing tails” – did the internet provide an answer.

Apparently, wolves can and do bite the tails off hapless bison calves. Furthermore, wolves can castrate bison – leaving them to grow to full size, minus a few parts. Thus, the tail-less bison.

Yellowstone Park is an exceptional place, a haven where people can glimpse a bit of the incredible world that lies beyond the realm of our human society. Yes, there is an element of the Wildlife Zoo in Yellowstone, and I worry that tourists view it as a Disneyland, where it’s all for our entertainment (it was, after all, created in 1872 as a “pleasuring-ground for the benefit and enjoyment of the people.”). Yet, people from across the globe visit Yellowstone, and many must come away with a new appreciation for the wildlife, the flora, the land itself. That appreciation may translate into a desire to contribute towards responsible stewardship of such places, as the chance to see a hint of the complex life interwoven into a magnificent landscape – to witness such things as a bison mother beating off a raven – opens up new ways of thinking, new perspectives. It also provides a new understanding of some of what goes on in that vibrant, wild community.

Such as the fact that there are bison without tails, and wolves who sometimes get only a tidbit of a meal when they are looking for more. 

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