Wednesday, February 19, 2014, saw 17 bison shipped off to a slaughterhouse. They were sent to slaughter for the unpardonable offense of having stepped outside of Yellowstone National Park’s invisible borders. Last week, another 25 bison were shipped off to their fates, 20 to be slaughtered and another five bison being sent to a research and animal testing facility. Yellowstone National Park is the site of some of the only remaining wild bison left today. While these wild bison are considered to be rarities, Yellowstone National Park is now caught between allowing the herds to roam freely and catering to Montana’s agribusiness which believes that these wild bison may infect their cattle herds with a disease known as brucellosis.
Ironically, brucellosis was transferred to the wild Yellowstone bison in 1917 from domestic cattle which were grazing in the park. It appears that the wild Yellowstone bison have developed natural resistance and immunity to brucellosis as they typically do not show any symptoms of the disease. In response to their exposure, their bodies have managed to create immunities against it and have cleared the disease out of their systems. To date, there are no known cases where a wild bison has been found to have infected domesticated cattle.
Brucellosis is a disease which may cause cattle to spontaneously abort and may cause male reproductive lesions, arthritis, and bursitis. Humans have symptom which include recurrent fever, flu-like symptoms, joint pain, and arthritis. The disease has been almost eliminated from domestic cattle herds in the United States. One of the few remaining pockets of the disease is still in the Greater Yellowstone Area. The disease has been found in livestock, elk, and bison. There is a consideration that the disease located in the Yellowstone bison is non-transferrable and that it is simply a marker that the animal has already contracted the disease and become immune. This would be similar to humans having a testable and identifiable marker for a disease they once suffered through but no longer have. This might include such things as childhood diseases where the patient no longer has symptoms, nor can they pass this disease on to others.
In fact, if a wild bison should contract the disease brucellosis, it is extremely unlikely that they either would, or even can, pass it on. One of the largest possible means of infection occurs when an animal ingests infected byproducts from a either a live birth or abortion. Additionally, when the pregnant female is infected with brucellosis, she sheds the bacteria with her first pregnancy. Her uterus will thereafter protect itself from shedding any additional bacteria with subsequent calves even if she is infected again. Also, the brucellosis bacteria will not survive in warmer temperatures or in direct exposure to sunlight and so the ability to transmit this disease is of an extremely low possibility. Because of the boundaries of the park, the typical grazing areas, and the seasonal movement of both bison and livestock cattle, there is almost no contact between the wild bison and the ranchers’ livestock herds, especially at those critical points in the year.
The Yellowstone National Park area is caught in the battle between where cattle ranchers graze their livestock and protected areas where wild bison live and graze. A number of smaller ranchers have allowed wild bison to roam their properties and there has not been any occurrence of disease transmission between the wild animals and rancher’s stock.
While the wild bison appear to have developed immunity to brucellosis but still show markers for the disease, it may actually be counter-productive to slaughter them in an effort to keep brucellosis at bay. Because the bacteria may be spread through bodily fluids, those people who are working in the slaughterhouse or veterinarians are at greater risk for contracting the disease. The hunters themselves are at a heightened risk as they may be exposing themselves by inhaling the bacteria while dressing the animal, coming into contact with the bacteria through an open wound, or even eating undercooked or raw meat from the infected animal.
All of these would be of greater concern if the wild bison were infected and able to pass the bacteria to others. This does not seem to be likely. Caught between the needs 0f bison and agribusiness, the Yellowstone National Park wild bison are one of the major triumphs of American conservationism. Once, American bison population was down to approximately two dozen animals. From those last remaining few, the bison became protected and the numbers rose to the periodically changing population of 2,300-5,000 animals. Bison are not considered either endangered or threatened. What makes the Yellowstone bison unique is that they are one of the last remaining vestiges of the wild plains bison still in existence.
Notwithstanding this unique accomplishment, in the middle of February, 2014, Yellowstone officials began to round up these wild bison for slaughter. All in all, approximately 600 animals will be sent to the slaughterhouses based on the recently passed $956 billion farm bill. Montana’s agribusiness, including cattle ranchers and Montana’s Department of Livestock, believe that these wild bison are one of the major threats to the $3 billion annual cattle business.
Some biology experts believe that the wild plains bison roaming in Yellowstone are an irreplaceable and unique resource. The arguments for and against these killing measures generally come down to two types of opinions.
Wildlife advocates and environmentalists support the idea that any brucellosis transfer between wild bison and domestic cattle is extremely unlikely. The cattle ranchers, among others, argue this idea with the belief that, however improbable, there is still the possibility.
Meanwhile, this year’s bison slaughter continues and will not stop until the casualty count reaches in the hundreds. Yellowstone National Park, founded in 1872 to become America’s first national park, appears to be caught between caring for the wild bison and catering to Montana’s cattle agribusiness. This issue seems to be just another division between two of American’s largest factions, agribusiness and environmentalists.
By Dee Mueller