The Santa Cruz Puma Project uses hounds to track and capture mountain lions, but the practice has come under pressure since the 2012 ban on hunting with dogs.
by Brendan Bane
Feb. 5, 2015—When wildlife biologist Paul Houghtaling needs to capture a mountain lion, he employs a certain set of tools. He needs his trusty ATV, which he uses to traverse the hills and trails of the Santa Cruz Mountains. He also needs a telemetry device, which helps him hone in on signals emitted by the GPS collars worn by his study animals. But one tool is paramount above all. To capture a mountain lion, Houghtaling needs hounds.
Houghtaling is a member of the Puma Project, a UCSC research group led by Chris Wilmers, one of the Land Trust of Santa Cruz County’s 2014 conservationists of the year. Their team uses specialized collars equipped with accelerometers (just like in your smartphone) that track what the cats are doing and where they’re going. When the team needs to physically assess one of their study animals or collar a new cat, Houghtaling reaches out to houndsmen like Troy Collinsworth, whose dogs are trained to track down mountain lions and drive them up trees where they can be darted and captured.
In this video provided by Troy Collinsworth, hounds bark and bay as a mountain lion tracked and tranquilized by Puma Project researchers grows sleepy. Story continues below.
Here’s how it works: Houghtaling begins zeroing in on a cat by baiting the area he believes it’s patrolling with a deer carcass. If the cat eats, he lays out another carcass, which he equips with a device that sends an email when moved. If the device is triggered and Houghtaling receives his dead deer email, he and Collinsworth meet up in the morning to capture the cat. Once at the kill site, Houghtaling listens for pumas on his telemetry device (it clicks faintly when the cat is far and clearly when it’s close). Collinsworth’s hounds immediately launch into tracking mode. The dogs let out a high-pitched bark to signal when they’ve caught the scent. A completely different bark follows when they’re honing in. The whole process can take a few hours, depending on weather (rain can wash odor molecules away) and how far the mountain lion traveled from where it left a scent.
Wondering why a puma would climb a tree instead of outrunning the hounds? Evolution is why. From the cat’s perspective, which was developed over a timescale that precedes guns and houndsmen, climbing a tree to escape predators is a pretty good strategy. PhD candidate Caleb Bryce, who studies canine physiology at UCSC, speculates further.
“My sense is that pumas have an innate ‘flee instinct’ to avoid predators or other threats,” Bryce explains. “While they may not have many natural (non-human) predators now, they evolved with other large carnivores (grizzlies, wolves, etc.), which present formidable threats. Multiple barking dogs, however small and ‘non-threatening,' seem to be enough to trigger the flee response, and the pumas typically run up a tree since the dogs can't follow.”
Mountain lions are also just plain built differently from hounds, another reason for their run-and-hide behavior. “Pumas are cryptic ambush hunters while dogs and wolves are cursorial, long-distance chasers, so there's probably a really interesting start-stop flee in the pumas and a constant chase for the hounds,” says Bryce. Combine their endurance with their remaining skill set and it’s easy to see why hounds are unrivaled trackers.
How A Hound's Nose Works
“When you train a dog to do a task,” says Collinsworth, “that’s what they’re focused to do. They’re not out to chase every squirrel or rabbit. They want to go out and do a very specific job.” Collinsworth started training his dogs when they were pups. They learn by tracking alongside older, experienced dogs and search only for small territory game like raccoons or foxes. They graduate to big game when they’re more experienced. Lifelong training helps, but the real skill comes from their incredible olfactory equipment.
Nestled inside your nose are roughly 6 million olfactory receptors: nerve cells that send electrochemical signals to your brain when triggered by odor molecules. Now multiply that pitiful number by 50; hounds have 300 million olfactory receptors. Not only do they have humans outgunned, hounds even breathe differently than us. A specialized tissue inside their nose directs a portion of inhaled air away from their lungs and into an area loaded with olfactory receptors. That trick helps them pick up on incredibly minute changes in scent trails left by other animals.
When a mountain lion leaves its prey, it leaves a trail of odor molecules behind it. Because those molecules disperse into the atmosphere over time, the scent is faintest at the kill site and stronger the closer you get to the lion. Hounds use this gradient to distinguish which direction the lion traveled. They can detect scent in parts per trillions, wriggle their nostrils independently and even tell which nostril inhaled which odor. Because of their unequaled olfactory equipment, many other tracking methods pale in comparison. “If researchers had just one capture method for bears, bobcats and mountain lions,” says Dan Tichenor, another houndsman for the Puma Project, “the vast majority of them would choose trail hounds. They’re the safest and most reliable.”
A Hunting Ban Complicates Research
Houndsmen like Collinsworth and Tichenor are a dying breed. California legislation enacted in 2012 outlawed the use of hounds to pursue bears and bobcats. Mountain lion hunting of any kind was banned in 1990. A last-minute amendment to the 2012 legislation granted an exception to hounds used for research, but training the dogs to pursue big game was still made illegal.
“It really hurt to have it all taken away,” says Collinsworth. “It’s my tradition. It’s my lifestyle. Many other people and I had it jerked out from underneath us, and it hurt.” Collinsworth’s dogs were trained to track mountain lions before those restrictions were passed. Without a way to train new dogs, though, they may be the last of their kind in the state.
“The houndsmen we work with come from the bear hunting community,” says Houghtaling. “But since there’s no bear hunting with hounds in California it’s kind of expected that this community that supports what we do will dwindle.” Houghtaling’s team may have to turn to out-of-state houndsmen for help, a potentially expensive and logistically difficult option. Collinsworth and Tichenor volunteer their dogs and time to the Puma Project.
For now, those two and their hounds are still dedicating their time and noses to help the research group pursue big cats. The Puma Project and its collaborators have generated a multitude of studies, many with wide-ranging implications for conservation biology. Their efforts help scientists to understand how pumas respond to changes in the ecosystem, and to predict how predator populations will fare to future shifts. Though big game-hunting hounds will eventually fade from California, their contributions may help keep mountain lions to stick around that much longer.
Also by Brendan Bane
Why Does The Puma Cross The Road?
Protecting Goats And Lions
Read about the Land Trust's successful campaign to raise money for a wildlife crossing under Highway 17: They Did It!
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