BOULDER COUNTY, Colo. — The Boulder County Sheriff’s Office continues to investigate the discovery of human remains first found by hikers and then located later by Front Range Rescue Dogs.

Hikers alerted deputies after spotting human remains near Lefthand Reservoir in the Brainard Lakes Recreation Area on Monday. When they returned to show deputies, they couldn’t find them. The Boulder County Sheriff’s Office called in Front Range Rescue Dogs. The team was able to lead investigators to the remains.

John Kirkpatrick, his wife and their dogs are part of Front Range Rescue Dogs. Kirkpatrick was on the team that helped track down the remains.

“We actually train our dogs to know the difference between an animal bone and a human bone. And there is enough scent difference between those two items that the dogs have a high level of accuracy of defining what bone is what type,” said Kirkpatrick.

His wife joined the volunteer group 15 years ago. After hearing of her experiences and the searches, he got certified and joined the team. While it’s a big time commitment for volunteers, it’s also extremely rewarding.

“What we always tell people that ask if they want to join our group, ‘If you are the kind of person who wants to get up at 2 a.m. in a snowstorm and go look for someone, you’ll do great in our group,'” said Kirkpatrick.

While these dogs are born with a great sense of smell, it takes years of training to refine their skills. It takes two years for dogs to become certified, but many don’t make it through the rigorous process.

“It’s very difficult because you put a huge investment in the dog,” said Kirkpatrick. “Many don’t make it through because it is a very difficult process.”

While Front Range Rescue Dogs mainly respond to calls with the Boulder County Sheriff’s Office, they can be directed to assist in cases across the state.

On Saturday, the Boulder County Coroner’s Office had identified the remains as those of Ernest Macaulay. He was last seen Sept. 28, 2011. He was 72 years old at the time.