Wildlife officers trap and relocate 20 bighorn sheep to bolster population
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COLORADO SPRINGS — On a chilly morning just after sunrise in early February, outside the famous Garden of the Gods craggy rock formations, a caravan of eight pick-up trucks packed with 65 volunteers and Colorado Parks and Wildlife (CPW) staffers waited in line along a narrow dirt road.
This was the big day CPW had been planning for more than three years to capture and translocate a group of 20 sheep from what’s known as the Rampart Range Herd in Colorado Springs to an area two hours away, west of Pueblo.
Trapping and translocating bighorn sheep, the official state animal, is one of the few mechanisms wildlife officers have at their disposal to bolster the population. Certain herds in the state have suffered catastrophic die-offs from pneumonia, and by establishing new herds in free habitat, it helps the population’s numbers recover.
On a plateau a quarter mile away from the caravan, a small group of Colorado Parks and Wildlife (CPW) officers followed the routine they had followed for the past 33 days, honking their horns every few minutes to alert the nearby bighorn sheep of their presence and of the alfalfa and apple mash they’d strewn about as bait.
Once a herd of approximately 30 sheep had gathered to eat the bait the team dropped the 70 by 70 foot mesh net they’d hung overhead and sprinted toward the sheep.
“They've been patiently waiting for the right composition of sheep to come in under the net,” said Julie Stiver, senior wildlife biologist for CPW's Southeast Region.
“We want to start this new herd with a couple ewes [adult females], a couple of lambs and some young rams [adult males].”
The team drops the net and runs to safely wrest the sheep from the netting and get them ready for transport. Video: Andrea Kramar, Rocky Mountain PBS
After the small team of CPW staff lures the sheep and drops the net, trucks of staff and volunteers come quickly to assist. Video: Andrea Kramar, Rocky Mountain PBS
Since the settlements of the 1800s, bighorn sheep numbers have fluctuated but never returned anywhere near their pre-European settlement numbers, when CPW estimates they numbered about 2 million. Habitat loss, increased recreation on the land, and most potently, disease, have plagued the population, which currently numbers around 7,000.
“Sometimes we have entire herds that blink out because of disease outbreaks,”
said Stiver. “So what we're doing here by spreading them out is that if a herd somewhere else blinks out, we've got a herd that's left in this new suitable habitat.”
Video: Cormac McCrimmon and Andrea Kramar, Rocky Mountain PBS
Bighorn sheep respiratory disease, transmitted by domestic sheep and goats through nose-to-nose contact with bighorn sheep, is the leading infectious cause of death for the species. While these bacteria are usually innocuous to livestock, they can rapidly develop into deadly cases of pneumonia in wild sheep.
“Right now our bighorn sheep in Colorado are doing worse than I've seen bighorn sheep do in the state for the 15-or-so-years that I've been involved [in this work],” said Karen Fox, a veterinary pathologist and research scientist at Colorado State University, who assisted with the operation.
“It's something that we don't know if it's going to get better or worse,” she said.
In 2023, out of 72 herds in the state, three herds suffered all-age die-offs, and another four herds were riddled with a form of pneumonia that largely afflicted lambs.
“In some herds we lose nearly every lamb every year [from respiratory disease]. What that results in is kind of a hollowing out of the population,” said Terry Meyers, executive director of the Rocky Mountain Bighorn Society.
CPW identified the Rampart Range herd as disease-free through various monitoring, testing and capture projects through the years and will start a new herd in recently opened habitat west of Pueblo,
“It's important for us to make sure that we are not moving diseases around the landscape,” said Ty Woodward, a CPW wildlife biologist in the Colorado Springs area, who led the February translocation operation.
The agency also tries to keep source herds, including the Rampart Range Herd, which numbers around 150, at healthy, stable levels. If the herd grows too large, disease propagates more easily. Removing and relocating some sheep from this herd will help mitigate this potential.
Where there’s smoke, there’s fire — and opportunity
In 2016, the Junkins Fire, which burned 18,000 acres west of Pueblo near the town of Westcliffe, opened a unique tract of land for bighorn sheep.
The fire cleared back much of the trees and dense brush in the area, opening up new habitat for sheep.
Bighorn sheep prefer steep terrain with few visual obstructions or tree cover, said Woodward. This type of terrain is especially important during the spring, when ewes (female sheep) give birth to lambs and need to be able to quickly flee from predators.
Woodward and team drive to the site of the Junkins burn scar to meet the trailers of sheep. Video: Cormac McCrimmon, Rocky Mountain PBS
“A lot of times people’s assumptions are, ‘Oh, that place is dead now. There’s nothing good there,” said Woodward. “In reality, a lot of these fire scars are our most productive wildlife habitats.”
CPW had been monitoring the Junkins burn scar to ensure there were no nearby domestic sheep or goats that could spread disease, nor sick wild sheep populations.
The area is managed by the U.S. Forest Service, and CPW partnered with them to establish the new habitat.
Weighing the risks and rewards of an operation
Capturing and relocating bighorn sheep is the second most intensive operation CPW conducts within Colorado. Only pronghorn sheep require more personnel and logistics, the agency said.
A mix of veterinarians, vet techs, CPW wildlife biologists, volunteers and partner agencies came to help out with the day-long operation in early February.
“[The sheep] become very stressed under these situations,” said Stiver. “We think that the benefits of what we're doing far outweigh the risks.” Video: Andrea Kramar, Rocky Mountain PBS
As soon as the CPW agents let down the net through a remote control, additional staff rushed to untangle the sheep from the netting.
Small groups of three to five people gathered around each sheep. After removing the netting, the staff blindfolded the sheep and applied hobbles to their legs.
“Darkness makes them feel more comfortable,” said Cory Adler, district wildlife manager for CPW in the El Paso County and Colorado Springs area. “When they can’t see what’s happening, it calms them down.”
Hobbles — devices that tie an animal’s hooves together — were applied to prevent the sheep from injuring the handlers.
“Our first priority is human safety,” said Woodward.
Staff monitored the animals’ temperatures and gave them enemas to ensure they wouldn’t overheat. Staff also administered oxygen through small tubes running through the sheep’s nostrils.
A team conducts a nasal swab on a ewe. Once the test results return, if any sheep comes back positive for respiratory disease, the team will be able to locate the sheep through its GPS collar. Video: Andrea Kramar, Rocky Mountain PBS
They applied GPS collars to their necks to track them over the next few years and logged each animal’s age and sex. They also drew blood and ran nasal swabs to test for respiratory disease.
Two sheep died during the operation. One ewe died almost immediately after the net came down, and a ram, who several staff tried unsuccessfully to resuscitate, also died.
“Ideally, obviously we would have no mortality involved with this,” said Woodward. “It’s something we don’t take lightly at all because when we do start taking it lightly, then we have serious issues.”
“You remember those for the rest of your career,” said Stiver. “For all the preparations and everything we do, they are wild animals.”
Stiver said losing one to two animals in an operation like this is not abnormal.
The dead ewe that was caught in the netting is loaded onto a truck. After the ram died, the staff ceased administering the tranquilizer BAM (butorphanol, azaperone, and medetomidine) to the remaining sheep as a precaution, for fear it could have contributed to the ram’s death. Video: Andrea Kramar, Rocky Mountain PBS
Losing a ram was especially disappointing to the crew due to their importance in procreating. The team hoped for three rams, but ultimately ended with two.
The two sheep who died will be necropsied — an autopsy for animals — and tested for pneumonia.
Translocation as way of conservation
The first translocation of wild sheep happened in 1922, when 20 Rocky Mountain bighorn sheep from Alberta, Canada were released into Montana and South Dakota.
In Colorado, the first translocation of sheep occurred in the 1940s, a time when the sheep population was dwindling rapidly.
“Those didn't really get ramped up until the 1970s or so. Through the 1970s and the 1980s, there were over 100 transplants that happened in the state,” said Terry Meyers, executive director of the Rocky Mountain Bighorn Society.
Today, the agency runs bighorn sheep transport operations about once every three years — either by trailer or helicopter if the terrain is difficult to access.
“These trap and translocation projects have been a big part of our success in Colorado,” said Woodward.
In Colorado, other species that have been trapped and translocated by state wildlife officials include the gray wolf, reintroduced from Oregon and British Colombia starting in 2023, and the swift fox.
Hope rides on a new landscape
Three trailers carrying the sheep safely arrived at the Junkins Fire burn scar two hours after they were loaded up from Colorado Springs.
A small group of about 15 people, mostly from CPW and the U.S. Forest Service, watched in excitement as the sheep were released from the trailers, one by one.
CPW officers release the 20 wild sheep at their new home west of Pueblo. Video: Cormac McCrimmon, Rocky Mountain PBS
The sheep raced out of the trailers and up the mountain, trekking through deep snow and wind. Video: Cormac McCrimmon, Rocky Mountain PBS
Some of the sheep were more frazzled than others, their sedatives slow to wear off, as they hopped out of the trailers and ran through the deep snow and fierce winds. Once they got their bearings, they traversed up the mountainside.
The staff took photos and gazed upward with their binoculars, huge sighs of relief passing over their faces.
“They've got a lot of hope riding on the success of them,” said Woodward.
For the next few years, CPW will be closely monitoring the herd, all adult males and females that total 15 in all, to ensure it remains disease-free.
Woodward, who led the operation and had gotten little sleep the night before, said he was going to take the following day off and go fishing.
Type of story: News
Based on facts, either observed and verified firsthand by the reporter, or reported and verified from knowledgeable sources.
Based on facts, either observed and verified firsthand by the reporter, or reported and verified from knowledgeable sources.
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