Sunday, March 07, 2021

’Copter-based collar work means stressful day for elk, but aids research for good of species

If elk could talk, four of them near Aspen would have quite the story to tell their herdmates about what they experienced Friday morning.

There, each one of them was, minding its own business, when in swooped this noisy, airborne contraption, from which a net was shot its way. Before the elk knew it, it was being hobbled, blindfolded, and wrapped in a sling, to be hauled off dangling beneath a helicopter to a location where humans awaited to sedate it and give it what amounted to a quick physical in the field.

The elk was then released, still a bit dazed and confused by its experience, and began making it way back to its herd, with three of the four wearing newly placed collars on their necks.

Though they were unharmed, it was perhaps not these animals’ best day. But their experience was for the good of their species in western Colorado. What they underwent was part of a research project by Colorado Parks and Wildlife aimed at studying declines in elk numbers in parts of the Western Slope and factors that might be contributing, from recreation, to development, to predation.

Winter is a busy time for aviation-related work by CPW. It’s when agency staff flying in airplanes and helicopters do winter counts of deer and elk, classifying the animals they see by age and health to help determine herd health.

But the more hands-on, capturing-and-collaring project of which Friday’s work was a part is a six-year project that started in 2019 and is aimed at better understanding the drop in what’s called recruitment in elk herds. That’s a reference to how many elk calves survive long enough to become part of the adult populations, at which point each animal’s odds of long-term survival are far higher.

“We have been seeing a steady decline in that (recruitment) number over the last 15 or 20 years,” Nathaniel Rayl, a big-game researcher leading the study, said Friday before the start of the helicopter-facilitated collaring work.


The focus of the day’s work was the Avalanche Creek elk herd, which is spread out through much of the Roaring Fork Valley. Matt Yamashita, CPW’s area wildlife manager in Glenwood Springs, said that historically the herd had a ratio of about 50 calves for every 100 cows. Now as few as 30 or fewer calves are being seen for every 100 cows — not enough to sustain an elk population over the long term.

The concern isn’t just in the Roaring Fork Valley, and neither is the focus of the research project. Crews planned to conclude work in the Roaring Fork Valley this weekend by collaring a total of 40 pregnant elk at various locations there, before moving on to do the same on the Uncompahgre Plateau, and then collar 20 elk at the new Fishers Peak State Park near Trinidad.

Earlier this week they collared 40 elk in the Bears Ears herd in the Craig area. For the study’s purpose, that herd is serving as a control, reference herd — a healthy one with the highest recruitment in the state.

Pregnant cows also are fitted with vaginal implant transmitters. When their calves are born this spring, the transmitters fall onto the ground and communicate with the radio collars on the mother elks’ necks, said Yamashita. CPW crews are alerted and head quickly to a transmitter’s location, and are able to find the newborn calf and collar it.

CPW says it plans to use the information obtained from collared cows and calves to assess herd health, estimate survival rates, identify major sources of mortality and evaluate the influence of human recreation on herds. Yamashita said collars that stop moving eventually send out a mortality signal, and CPW can then investigate what caused the death, from predation, to road kill, to harvest by a hunter.


Researchers also are trying to determine to what degree recreation use by hikers, backcountry skiers, bikers, motorized-vehicle users and others may be displacing herds from areas. It’s a concern that’s only increasing due to the explosion in recreation on public land in places like the Roaring Fork Valley and the Uncompahgre Plateau.

John Groves, district wildlife manager in Carbondale for CPW, said local outdoor recreation was “off the hook this year.”

“It seemed like an exponential increase … but we’ve been seeing that for the last 10 years, anyways, if not more, which we understand. People want to get out and recreate. The challenge is how to manage between wildlife needs and the desire to recreate.”

He said that’s why CPW already uses seasonal closures in places. At certain times of year recreation may not have much impact, but at others times it does, such as in calving season, and in winter on critical winter range, he said.

The pandemic helped drive up outdoor recreation activity last year, and Groves thinks it could contribute to longer-term increases. People have been escaping cities and buying up homes locally, realizing they can live anywhere and work virtually.

Another concern is that people more frequently are pushing farther into backcountry big-game habitat than ever before. Better, lighter gear, such as for skiing, helps foster this, as does a drive by adventurous skiers, mountain bikers, trail runners and others to explore new areas.

“They’re going farther into the woods than 20 years ago they did,” Groves said. “So there used to be some of those areas that wouldn’t see people. Those areas are being impacted more and more.”

Yamashita said the Uncompahgre Plateau gets considerable motorized use and is seeing a significant increase in recreation as well.

He said multiple factors likely are contributing to a decline in elk numbers. The study could help shed more light on what’s going on, and what might be done about it, in a state that historically has boasted of having the largest elk herd in the continental United States.

“We’re slowly declining,” in elk numbers, Yamashita said. “We’re slowly coming to a point where we may lose that status and stature.”


Those involved in Friday’s work are doing their part to keep that from happening. Among them was Harley Cushman, of Cody, Wyoming, who works for Quicksilver Air Inc., the contract helicopter involved with the work. On this day he was the helicopter’s field truck driver. Other times he works as a “mugger” on the ’copter crew.

An airplane was used Friday to spot elk from the air, aided by GPS data and radio transmissions from previously collared elks, and fresh tracks from snow the previous day. Then the helicopter crew headed in, worked the elk to a good spot, and the net gunner leaned out and fired a net at a cow elk. In what sounds a bit like a rodeo sport, the mugger and net gunner then jumped out of the helicopter to hobble and blindfold the animal, disentangle it from the net and position it in the sling to be flown away.

Crews on Friday sought to capture elk within a mile or so of where ground crews would work on them.

“We don’t want to fly them for 10, 20 miles at a time. We want to minimize the risk,” Yamashita said.

Cushman said the Quicksilver crew makes quality animal handling a priority, trying to cause the least harm possible.

“You’re putting them in a very high-stress situation. I mean, they certainly think it’s a giant eagle … or a fire-breathing dragon. But we really try to work these animals calm. I think, obviously, at the end of the day we all want to go home in one piece, and we want all the animals to go about their lives as usual,” Cushman said.

He called the job “a fun gig” that lets him see beautiful western scenery from the air. But it’s dangerous as well, with helicopter capture crews globally typically suffering at least one wreck a year, often fatal, he said. He remembers a snow squall moving in on an airborne crew he was part of once near Salida and the helicopter’s blades quickly icing up. Fortunately, the “very competent pilot” was able to promptly and safely land the helicopter, Cushman said.


Crews worked in sunny conditions Friday, hauling the elk to the CPW work site on private ranch land. There, veterinarians administered an immobilization drug and joined others in getting to work taking the animals’ temperature, drawing blood samples, using ultrasound to see if they were pregnant, collaring and installing vaginal transmitters in the three that were, checking the animals’ ages by inspecting their teeth, and so on.

The vets monitored the animals to make sure they weren’t getting too hot. They can use medicine and cold-water enemas to cool the animals, or if need be simply release them without processing if overheating remains a concern.

While the drug used to immobilized the animals doesn’t totally knock them out, it “helps them forget the experience, so that’s always a nice thing,” said Mary Wood, state wildlife veterinarian for CPW.

Once the ground crews finished their work on the animals, typically within 15 minutes or so, a reversal drug was administered that quickly rejuvenated them and they were released in the direction from which they were captured. Pink flagging on their collar indicated they’d already been captured, to keep the helicopter crew from inadvertently putting them through the same experience more than once during the day’s work.

Wood was pretty happy with how things went with the four elk in the day’s first operation. None were hot, and there weren’t signs of health issues. A few were on the skinny side but the last two were “actually quite fat,” she said.

“We didn’t see any injuries. The processing time was pretty quick, so they weren’t down very long — what we like to see,” Wood said.

Eden Vardy, a member of the Colorado Parks and Wildlife Commission who grew up in and lives in the Aspen area, was on hand with his daughter, Jasper, 7, to watch Friday’s work. He said he still sees a lot of elk in the area, but not as many as when he was growing up.

He’s happy to see the elk research taking place.

“I think the balance of recreation and conservation is always at the forefront at the commission table,” Vardy said. “… We know we have a lot of work to do, but getting good physical science helps us make the best decisions.”

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