Denver using 'raptor poles' to control wildlife

They'll erect "raptor poles" above problem prairie-dog colonies — perches for red-tailed, Swainson's and ferruginous hawks and other sharp-taloned predators.

The idea is to encourage natural predators to rein in animals that are damaging the landscaping and evading non-lethal control methods.

The morphing of traditional square bluegrass parks into vast connected corridors in urban areas is widely welcomed by people who love open space. But the animals — prairie dogs, deer, geese, raccoons, coyotes, skunks and foxes — use it as habitat. They find water, food and protection.

"The better the natural predation, the better it is for the ecosystems at large," said Scott Gilmore, deputy manager of Denver Parks and Recreation and a wildlife biologist.

Gilmore is overseeing the installation of wooden poles north of the Stapleton neighborhood, near the Northfield mall, where expanding prairie- dog colonies are devouring wider and wider swaths of grass, he said.

Parks crews first tried luring prairie dogs with molasses-laced traps and relocating them. This is complicated because a state law requires approval by county commissioners before prairie dogs can be moved to a different county — assuming prairie dogs take the bait.

"They're not going into the traps anymore," Gilmore said.

Then, parks managers killed problem populations and donated carcasses to recovery centers for raptors and ferrets. But colonies in east Denver, along the border with Aurora, still were expanding last summer. Prairie dogs don't drink. They get the water they need by eating vegetation.

So parks crews this fall resorted to poison gas, dropping Fumitoxin pellets into burrows, killing hundreds. Residents who saw warning signs posted during the operation objected.