A British Columbia mule with a nose that knows is helping investigators trying to crack a cold case in Arizona.
Chelsea Grimm vanished while on a cross-country road trip in 2023. Her vehicle was found abandoned on a forest service road in the Kaibab National Forest, just south of the Grand Canyon.
Now, Sonny, a scent-detecting mule, and his human, Princeton Ground Search and Rescue (PGSAR) volunteer Marion Weiskopff, have joined in a private search to try and find any trace of the missing woman.
Weiskopff and Sonny are a part of B.C.’s only dedicated mounted search-and-rescue team, but this is the first time they’ve been called on for his scent detection skills.
“When he picks up a smell, he stops dead in his tracks and he takes the air in, like you can hear him sniffing the air, and then he just turns [to] where the scent is coming from,” Weiskopff explained.
Sonny the mule and Marion Weisskopff are handed an award for winning a scenting field trial in Oregon in 2024. (Marion Weisskopff)
Sonny honed those abilities at training clinics in Oregon and Arizona several years ago, and went on to win equine scenting competitions in each state, Weiskopff told CBC’s Daybreak South.
“Sonny found the scent in about a 10-acre plot in under a minute and a half,” she explained. “Other horses often take 10 minutes and longer.”
A missing person poster for Chelsea Grimm seen in Arizona. (Marion Weisskopff)
Private investigator Steve Fishcher, who is working the search for Grimm, learned about Sonny through contacts in the search-and-rescue community.
When he learned that Weiskopff and her husband spend several months a year in Arizona with Sonny and their horses, he invited them to help scour a 400-square kilometre slice of the Arizona backcountry.
Marion Weiskopff and Sonny (right) and her husband Don and his SAR-certified horse Mariah (left) search the Arizona backcountry. (Marion Weiskopff)
It’s also a first for Fischer, who said while he’s familiar with scent-detecting equines, he hasn’t employed them before.
“Another team out of Florida called Peace River Search and Rescue, who I’ve been involved in searches with and who I really respect, they have an equine division … they even have a scent otter for underwater searches,” he said.
“So when the opportunity came up, I was very interested in it.”
Private investigator Steve Fischer on the site of the search for Chelsea Grimm as mounted teams assemble. (@SF_investigates / X)
Fischer said horses and mules add “great value” to search efforts because of the terrain they can cover.
Previous searches of the area using ATVs, drones and even cadaver dogs have come up empty handed.
“Being able to have those equines get into some of those areas that have been really difficult for us on foot is gonna give us the best chance and hopefully finding Chelsea if she’s out there,” he said.
Weiskopff said the goal of the current search is to find any possessions or remains that could help bring closure to Grimm’s family.
A piece of shoe that Sonny helped locate in the Arizona backcountry. (Marion Weisskopff)
“The mule actually found a torn off shoe, the bottom of a shoe, and it was a lady size shoe in the middle of nowhere, it wasn’t near a trail or anything, and he took me right too that,” she said.
“But because it’s just a sole they can’t really identify if it was Chelsea’s or not.”
Heavy rain and mud forced them to suspend the mounted search for safety reasons, Fischer said he hopes to do another large-scale search in drier weather.
While this is the first time Sonny has specifically put his nose to work, he and Weiskopff are no strangers to search-and-rescue work.
They’re part of PGSAR’s mounted search-and-rescue unit, composed of five trained volunteers with their own mounts, who master an additional list of 60 tasks for certification.
The Princeton Ground Search and Rescue mounted team. (Princeton Ground Search and Rescue)
PGSAR president Paul Fyfe said the unit is ideal for the region’s steep mountains and ranch-like grasslands.
“The horses do give a better advantage for access, but also for for view,” he said.
And while scent detection isn’t one of their official skills, Fyfe said it can play an informal role in search work.
“The equines give signals to anything interesting in the area through their sense of smell or through their ears,” he said.
“Being prey animals [they] are much more sort of aware of their surroundings.”
Fyfe said the team hasn’t ruled out getting more formal scent training for the unit like Weiskopff and Sonny.
