Predator control will help iconic birds like Gunnison sage grouse enjoy improved lives
Iconic birds and a recently transplanted herd of charismatic megafauna will get new chances on survival thanks to steps taken Wednesday by the Colorado Wildlife Commission.
The commission approved two predator-management plans submitted by Division of Wildlife biologists who said certain populations of Gunnison sage grouse and desert bighorn sheep are struggling because of hungry predators.
Although the vote was unanimous, it wasn’t an easy decision, said Division of Wildlife Director Tom Remington.
“This is the first time we’ve brought something like this to the commission and we don’t take it lightly at all,” Remington said. “Colorado has kept the bar very high on the topic of predator control. This is a difficult issue, one of the most contentious issues across the West (and) we are dealing with this more than any other western state.”
One plan will protect a small population of Gunnison sage-grouse in and around the Dan Noble State Wildlife Area and Miramonte Reservoir near Norwood where chick survival has been zero for the past four years, said Janet George, the DOW’s acting state terrestrial manager.
“The population is declining,” warned George. “Our research shows most of the chick loss is from coyote predation.”
One telling find: small radio transmitters initially placed on grouse chicks have been found in coyote scat.
The plan will focus primarily on eliminating coyotes but other predators won’t be ignored, George said.
“Predator control is only part of the whole strategy along with habitat work” and land acquisition, George said.
George said the Division will contract with Wildlife Services, the animal-damage-control arm of the U.S. Department of Agriculture, to kill coyotes.
The plan calls for aerial gunning and call-and-shoot elimination for two years.
One concern (although there are certain to be others) is what happens to other predator populations now being kept in check by the coyotes.
Research indicates so-called mesopredators, including skunks, foxes, raccoon and badgers, see an increase when coyotes have been removed from atop the food chain.
George said predator-control will target those animals as well.
Saving, or at least preserving, the Miramonte sage grouse population is important for several reasons, including the bird’s recent “warranted but precluded” Endangered Species Act ranking by the U.S. Fish and Wildlife Service.
This particular flock of birds is 80 percent of the entire San Miguel population, which numbers about 122 birds, George said.
There are only seven distinct populations of Gunnison sage-grouse in Colorado, with most of the birds (600-800) in the Gunnison Basin population. Some of the other populations have fewer than 10 birds.
The Gunnison sage-grouse isn’t yet protected by the ESA but with a listing priority of 2, it might not be long before the bird is listed.
And that’s something neither the state nor local landowners are eager to see, since it would affect every land-use decision where the birds may exist.
Desert bighorn sheep certainly aren’t endangered and are doing extremely well across their range in western Colorado.
It’s expanding that range where the problems arise.
Repeated attempts to locate sheep into Big Gypsum Valley south of Nucla have failed and DOW biologists are pointing fingers at mountain lions.
After a 1990 sheep transplant failed, another attempt was made in 2001, said Scot Wait, DOW Southwest Region terrestrial biologist.
“Eleven of the 12 (sheep) died and nine probably were mountain lion fatalities,” Wait said.
Research from other states indicates newly relocated desert bighorn sheep are susceptible to mountain lion predation until the sheep get used to their new habitat, Wait said.
The division earlier this month moved 15 desert bighorn into the area, 14 of the sheep wearing satellite radio collars for tracking and monitoring.
Wait said it’s possible the lion population in the area is growing because sheep unit 63 is a difficult area to hunt and hunters haven’t been able to meet the lion quota in recent years.
The commission approved a plan calling for removal of individual mountain lions only if that lion kills more than one sheep.
After some discussion, the commission amended the plan, giving the Division the option of removing a lion after one kill.
Wait said public hunters would be used whenever possible to remove the lions.