Study links Yellowstone bison fate to genetic flaw

Study links Yellowstone bison fate to genetic flaw [edited]

By Laura Zuckerman
Reuters
WBFO (public broadcasting)
February 7, 2011

SALMON, Idaho (Reuters) - A congenital defect combined with U.S. government plans to kill bison exposed to an infectious cattle disease could doom America's last wild herd of pure-bred buffalo at Yellowstone National Park, a genetics expert said in a new study.

The findings were posted on Monday in Nature Precedings, an online archive for pre-publication research by scientists, as the government and environmental groups clashed in court over an icon of Western wildlife that dates to prehistoric times. (The study is posted at http://precedings.nature.com/documents/5645/version/1)

A planned slaughter of captive bison that test positive for exposure to brucellosis was placed on hold by the National Park Service last week after conservationists brought a lawsuit challenging the program.

On Monday, the Park Service filed a response reasserting its right to kill as many as 1,600 head of buffalo this year, depending on how the winter progresses.

The agency denied environmentalists' claims that killing brucellosis-exposed buffalo -- 76 are already slated for slaughter -- would irreparably damage the herd.

But the study from Thomas Pringle, a biochemist on the genomic team for the University of California at Santa Cruz, faulted the government as overlooking a hereditary weakness in the bison herd that could be amplified by the culling program.

He found that most Yellowstone bison whose DNA were tested carried a genetic mutation that affects cellular metabolism and makes bison lethargic, rendering them less capable of foraging in deep snow, fending off predators and competing for mates.

Pringle, whose work on other genomes has appeared in professional journals such as Science and Nature, said his bison research demonstrates that culling of the wild herd based on brucellosis, rather on the health of their genes, may push the species over the edge into a form of extinction.

"They're taking a really high risk of killing bison with healthy genes and getting into a situation where they can't go back; the good DNA will be lost," said Pringle, whose paper relies on published genetic data, analyses of bison fossils and samples from herds at national parks like Yellowstone.

Pringle said he was motivated to release his findings in advance of scientific peer review because Yellowstone bison can't afford the months-long wait while his paper is accepted for formal publication.

A Yellowstone spokesman said the Park Service was not immediately acquainted with Pringle's study.

Full text: http://tinyurl.com/4hlthlr