Learning to monitor gray wolves from afar isn't simple, even if their call is one of the most easily recognizable sounds in nature.
Jut ask the University of Montana scientists who got promising results last week - and an unexpectedly close encounter with the controversial carnivore - at the launch of a pilot project using an innovative speaker-recorder system.
Called a Howlbox, the digital device is intended to monitor wolves remotely now that federal protection has ended and Montana, Idaho and Wyoming have assumed full management over animals within their borders.
The researchers planned to keep their distance - human scent might prompt their quarry to flee the area - but instead found themselves face to face with half of one pack on a snowy morning while scouting places to set up the Howlbox near old den sites and rendezvous areas, where wolves gather with their pups.
"I definitely thought we were busted, but we were able to get away without them noticing us," said Dave Ausband, a research associate at the Montana Cooperative Wildlife Research Unit, where the Howlbox was developed.
A few days later, researchers heard a wolf howling as they set up a Howlbox in another area, and then heard the wolf approaching to investigate what it presumably considered an interloper in its territory.
A week into the experiment, scientists said the Howlbox still has some problems at this early stage in its development.
But they were encouraged by preliminary data from the first three devices deployed in the Salmon River Mountains, which cross a rugged stretch of the Salmon-Challis National Forest in central Idaho.
One Howlbox worked as planned, one worked half the time and one worked for just 15 minutes - not bad considering they were built at a researcher's kitchen table using off-the-shelf technology and duct tape.
"You've got to use all your McGyver skills," said Teresa Loya, the research technician who is building the devices. "What's really cool is that one worked perfectly. We've got to work out the kinks, but it tells us that the Howlbox detected the presence of a wolf in an area where we knew they were. That's what it's supposed to do."
Researchers successfully tested a prototype Howlbox on a two-member pack in Montana in January, but the pilot project is a large-scale study that will last the summer using a smaller, lighter, less-expensive version of the device on 14 packs spread across Idaho.
The latest Howlbox, which broadcasts a howl and records wolves' responses, costs about $1,500 and weighs 8pounds. The Nez Perce tribe is funding much of the research.
The system is intended as a cost-efficient and less invasive tool to help Montana, Idaho and Wyoming manage wolves in the Northern Rockies following their removal from federal protection in March.
The states have adopted long-term management plans, although funding remains uncertain as federal money dries up for aerial tracking, catching and radio-collaring, which is the traditional but expensive and labor-intensive method used to monitor the far-roaming wolf.
State wildlife officials are looking at using audio recordings, DNA scat and hair samples, hunter surveys, tracks and public sightings to create a statistical model for the region's wolf population. The states also will continue to use some radio collars and global positioning system collars. Remote-triggered cameras also might be used.
Carolyn Sime, wolf management coordinator for the Montana Department of Fish, Wildlife and Parks, said the Howlbox's early results were promising.
"These things take time," she said. "It's part of the trial and error of new tools, but we need to keep our eye on the prize and invest in cost-effective ways to monitor these animals. We're not ready to scratch anything off the list yet."
Audio recording have been used in wildlife studies for decades, but the Howlbox is breaking new ground by using spectrogram technology, digital analysis, programmed instructions and solar power to remotely monitor wolves in the wild.
The device kicks on automatically at dawn and dusk, broadcasting a series of howls and recording any responses before entering a sleep mode until the next session.
The Howlbox system doesn't have the sophisticated software and high-quality recording capability to assign an acoustic signature to individual animals, which has been done in research with whales, birds and other wildlife.
But researchers still hope the recorder can be used to help detect the presence of packs, track their movements and provide a rough count of adults and pups.
"Wolves will never be cheap or easy to monitor, but we need to make sure these animals never go extinct again in the northern Rockies, so we need to be cost-effective and creative," Ausband said. "The public spent a lot of money to bring them back, so that makes the scrutiny and pressure higher."
Gray wolves, which were nearly exterminated from the continental United States by the 1930s, were protected under the federal Endangered Species Act in 1974.
They naturally recolonized northwest Montana in the early 1980s and were reintroduced in Wyoming and central Idaho in the mid-1990s. An estimated 1,500 wolves currently inhabit the northern Rockies.
Federal rules require Montana, Idaho and Wyoming, which have adopted wolf hunting seasons as part of their management plans, to maintain a minimum of 300 wolves, although officials say the region's actual population likely will be about 1,000.
The FWP Commission on Thursday set a tentative quota of 75 wolves for Montana's initial wolf hunt this fall. Agency officials predict the state's wolf population, estimated at more than 420 at the end of last year, will rise 20 percent annually when birth rates, hunting and other mortality factors are taken into account.
Idaho and Wyoming have classified wolves as predators that can be killed anytime in many areas within their borders, while Montana has adopted stricter rules on when wolves can be killed.
Conservation groups, which say the Northern Rockies need at least 2,000 to 5,000 wolves to maintain a healthy population, have filed a lawsuit in federal court in Missoula seeking to restore federal protection for wolves.
The groups also are seeking an emergency injunction to stop wolves from being killed as big-game animals and predators until the lawsuit is resolved.