"You enter a relationship with these dogs that you hope could one day save a life," said veteran Whistler ski patroller and rescue-dog handler Ian Bunbury.
He's trained four-year-old Henry since he was a puppy.
"We're a great team, we read each other really well, he knows what I expect," he said proudly as he zipped up Henry's special harness, which can even allow him to be lowered down helicopter lines during rescue operations.
Strong connection between dog and handler
Bunbury has spent thousands of hours training Henry, not only to be a well-behaved pet, but also to be able to track down and sniff out people buried under the snow.
Henry diligently obeys every command that Bunbury makes at his family's home above Whistler's Creekside neighbourhood.
The bond between the handler and his dog is loving, but intense.
"We are never apart. When I say I spend more time with this dog than with I do with my family, I'm not bragging about that. It's just the way it is," said Bunbury.
"He sleeps beside my bed. When my feet hit the floor he is like, 'OK, Dad, what are we going to do today?'"
Short window for rescue
As air moves across the snow, avalanche dogs are able to pick up the scent of a person below the snow. They are trained to run toward that scent, where rescuers will help them dig.
"He [Henry] can cover an area that it would take 50 people a day to cover, a dog can cover it in half an hour," said Bunbury.
People caught in avalanches have a short window for survival — often 30 minutes or less — so finding them fast is critical, said Bunbury.
"Henry is the guy. You are going to depend on him to save your life," said Bunbury as he put his dog through a number of training exercises in an area near Whistler's Roundhouse Lodge.
In a brief demonstration for CBC News, Henry sniffed out and ran straight for a piece of clothing that Bunbury had worn and buried earlier.
It only took perhaps a minute to find it, and maybe another minute to dig it out through the heavy snow.
His reward is a game of tug-of-war, as Bunbury loudly praised Henry for the successful find.
"That's really what we're exploiting here is the dog's prey drive, for him to hunt something and bring it back to the alpha leader of the relationship."
Bunbury says certain breeds like Border Collies, Labradors and German Shepherds are best for the job, but only the right kind of owner can match wits or have the energy to keep up with them.
"He's a super-athlete and a super-brainiac, too," Bunbury said of his dog.
"These Border Collies, they're actually smarter than they need to be to do this job."
Huge amount of terrain a challenge in B.C.
At Whistler-Blackcomb, a minimum of two dogs patrol each of the resort's two mountains every day during ski season.
Anne Kennedy and her nine-year-old Border Collie Seren patrol some of Canada's most expansive and challenging ski terrain on Blackcomb.
"Our main issue is our timely response to get somewhere," said Kennedy as she skied behind her speedy dog, who navigated the resort's steep slopes with ease.
"With this amount of terrain, that's the real issue."
Seren has never been called on to try and save a life in the six years since she became a validated avalanche rescue dog.
But Kennedy says she's able to search a huge area if a slide happens.
"She can clear 100 square metres in about 10 minutes," she said.
Still, Bunbury says that hope is what motivates him to put in so much time and effort training with Henry.
"I've been caught in avalanches and I'd never want anyone to go through the horror of being buried," says Bunbury, who grew up skiing in Whistler. He has been a patroller for 25 years with three different dogs.
"It would be the absolutely pinnacle of my career to have a live find — that's why I got into it."
Adventure-seekers heading into avalanche-prone areas are strongly advised to take tracking devices, and to be prepared to locate and dig out other members of their parties if they get into trouble.
But on or near resorts, the incredible noses of avalanche dogs like Henry are still crucial.
"People are going to get caught in avalanches.You want to save them," said Bunbury.
"The best day would be saving an avalanche victim."