The verdict is in — genetically speaking — on a troublesome bison herd in the Grand Canyon.

The state-owned bison herd has been straying from its range north of the canyon and venturing into Grand Canyon National Park (HCN, 4/28/03: Bison arrive in Grand Canyon uninvited). The state wants to leave the herd on the land because it brings in $40,000 a year in hunting license fees. But park scientists complain that the animals have been wallowing in riparian areas and trampling native plants.

The scientists thought the state would be willing to deport or kill the bison if they could prove that the animals were bison-cow half-breeds, left over from a “cattalo” breeding experiment. In November, scientists got the news they were waiting for: Preliminary tests showed that more than 90 percent of the animals do in fact harbor cow genes. The fate of the herd has not been decided.