A made-in-Montana alternative to Yellowstone bison slaughter

March 29, 2016

Guest opinion by Patricia M. Fazio, PhD.

A better solution for managing the American bison of Yellowstone National Park has Montana roots.

The immunocontraceptive vaccine porcine zona pellucida (native PZP) was first used 30 years ago by the late Billings’ reproductive physiologist Jay F. Kirkpatrick, Ph.D., for population control in wild horse herds and is now used in federal and tribal herds throughout the West, on East Coast barrier islands and in private sanctuaries.

It has been conclusively shown, more recently, that native PZP also works on bison in the Catalina Island herd off the coast of southern California. The British Broadcasting Corporation, National Public Radio and the Los Angeles Times have all reported on this project, which helps demonstrate that PZP could be used in Yellowstone National Park and anywhere else where there is a population surplus of bison, including zoos.

On Catalina Island, the 2010 calving rate for bison was 67.4 percent (29 calves from 43 cows). Through the use of native PZP, the calving rate was reduced to 10.4 percent by 2011 and to 3.3 percent by 2012. Considering the annual mortality rate of 2 to 5 percent documented during this study, the results demonstrate the potential of PZP use as an effective, nonlethal tool for controlling population growth in free-ranging bison.

Why national parks have not adopted this methodology is a mystery to me.

The National Park Service is a preservation agency, and bison are considered a native North American species, even though they evolved in the Asian steppes. This species has been in North America for about 150,000 years, having migrated east over the Bering Land Bridge. It is believed that bison (commonly known as buffalo) crossed this land bridge that once connected the Asian and North American continents. Through the centuries, they slowly moved southward, eventually reaching as far south as Mexico and as far east as the Atlantic Coast, extending south to Florida. But the largest herds were found on the plains and prairies from the Rocky Mountains east to the Mississippi River, and from Great Slave Lake in Canada to Texas.

I have proudly worn the NPS uniform. On the base of the shoulder patch is a white bison — part of the agency’s logo. Historically, this species has been held in high esteem, especially for the conservation efforts that saved it from complete extermination during the late 19th century.

PZP vaccination is inexpensive ($24 per dose) and may be delivered remotely via a dart gun. Don't we have enough bison "farms" already to give us the meat desired? I am not an animal rights activist but have a degree in animal science, and I find it unnecessary to slaughter these animals when there is a viable alternative in up-front, safe and inexpensive population control.

No wonder the NPS is restricting access to the slaughtering process. They are ashamed and well they should be. This is ignorance and insensitivity at the highest level. Shame on all of these officials. Bison are publicly owned wildlife, and transparency is required by law.

Patricia M. Fazio, Ph.D., is a scientific and environmental editor and writer in Cody, Wyo.

Originally published March 29, 2016, in the Billings Gazette

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