Steers are slimmer when prairie dogs are around, says a new study detailing competition between cattle and the rodents.
Prairie dogs in a big colony eat so much grass that cattle trying to graze the same range can’t bulk up as much as those on prairie-dog-free land, the Colorado State University study found.
The cost can be up to 38 pounds a season – roughly $38 per animal – according to CSU biologist Mike Antolin, one of the study’s authors.
Antolin and his colleagues also found no effect from small prairie dog colonies, occupying 5 percent or less of rangeland.
“We’re going to make everybody mad on this one,” Antolin said. “They have impact, but they’re not uniformly bad. Below a certain level, they don’t take enough grass to compete with cattle.”
The team’s work – published in Frontiers in Ecology and the Environment – is the first to calculate the economic toll exacted by prairie dogs on cattle production, Antolin said.
Where prairie dog colonies extended over 20 percent of a range, the dollar value of steers’ weight gain dropped by about 6 percent, according to the new study.
Weight gain dropped by nearly 14 percent where prairie dogs occupied 60 percent of the land.
Given the new data, ranchers shouldn’t bother trying to kill prairie dogs, said CSU extension agronomist Randy Buhler, who was not involved in the study.
The expense of bait, poison and labor to eliminate them “could be acutely hazardous to your profit,” Buhler, of the Logan County extension office, wrote in the High Plains/Midwest Ag Journal.
Brent Johnson, co-owner of Ocho Vaca Cattle Co. in Ault, said uncontrolled prairie dogs would destroy rangeland.
“If you just let it go, they would get it ate down to where you couldn’t harvest any forage off it,” Johnson said.
Johnson said he spent more than $2,000 to kill rodents on about 800 acres last year – more than in the past because prairie dogs have expanded with the drought.
Other ranching costs, such as hay, also are rising, he said.
Johnson said he plans to sell off his 110 Red Angus cattle this spring.
“It’s just no fun anymore,” he said, “because every time you turn around, something else is biting into your bottom line.”
Staff writer Katy Human can be reached at 303-954-1910 or khuman@denverpost.com.
