GARDINER, Mont. (AP) — Yellowstone National Park started shipping many of its famous wild bison to slaughter Wednesday to drive down the size of the park’s herds and respond to concerns by the livestock industry over a disease carried by the animals.

Thirty animals have been shipped to slaughterhouses, and officials plan to send an additional 63 in the next few days. The bison were weighed and tested for disease for research purposes, and the remaining animals were crowded into holding pens to await shipment.

The park’s actions are driven by an agreement in 2000 with Montana officials that requires it to control its bison herds. The meat will be distributed to American Indian tribes that traditionally subsisted on bison.

“Nobody here wants to be doing this,” park spokeswoman Jody Lyle said after the bison were prodded into trailers for shipment. “It’s time for a change.”

https://apnews.com/article/1f9c4b3648914236bc25d9479beff9b6

Herds of beautiful, massive bison move amongst the plains of their protector, Yellowstone National Park. These gentle giants are the last-known wild bison population in the entire world. This means that their DNA has not been tainted by breeding with cattle and domesticated bison. The Yellowstone bison stem from an original population of 25 that survived in Yellowstone during the mass bison killings of the 1800s and early 1900s. Yet, every year for the past 17 years, Yellowstone bison have been sent to the slaughterhouse. In 2017, more than 1,200 bison were slaughtered, the second most number of bison culled in the park’s history.

At the root of the culling is a disease called brucellosis. “In part why bison are being killed and captured is because the state of Montana does not have a tolerance for bison in the state,” says Morgan Warthin, Yellowstone’s public affairs specialist. “That is driven by the fear of brucellosis.”

Brucellosis is a bacterial disease that is highly contagious for cattle, bison, elk and deer. It is transmitted by way of aborted fetuses, although there has never been a documented case of brucellosis being transmitted from bison to cattle. The bacterial disease, mostly carried by females, can cause infertility, abortions and scarce milk production, making it a very terrifying illness for those who depend on livestock for their livelihood. Cattle livestock makes up two-thirds of Montana’s agriculture industry, the largest industry in the state.

(emphasis mine)

https://www.yellowstonepark.com/park/conservation/culling-last-wild-herd-bison/