Not many people can say they have helped with murder investigations, helicopter disasters or missing persons inquiries. Not many dogs can, either.

Taz, a border collie, is the senior search dog for Trossachs Search and Rescue. Along with his handler Gayle Wilde, he has been with the team for almost nine years.

Gayle and Taz are on call 365 days a year and receive no pay for their work – the whole team are volunteers.

At this year’s Crufts competition, Taz is nominated in the Extraordinary Life of a Working Dog category of the Friends for Life awards.

Friends for Life is a celebration of just how much dogs change and improve people’s lives. Five of the finalists will got to Crufts, held once again at the NEC in Birmingham, where the winner will be announced on Sunday March 11.

But despite Taz’s extraordinary achievements, handler Gayle believes the secret is that it’s all a bit of fun for the pooch.

“He’s a pet dog who loves playing a game, which happens to be finding people,” said Gayle, 39, of Kilsyth, who also works as a student counsellor and dog trainer.

Taz was picked up off the streets as a young puppy after being thrown out. Gayle picked him up from the pound when he was about four months old.

“It was one of those things. There was an instant connection. I think you know with dogs,” added Gayle.

“I saw the search and rescue team do a demonstration and thought, let’s try that out and we’ll see where it goes.”

Training a search and rescue dog takes between 18 months and three years. And Taz’s training has included abseiling, winch practice from a helicopter and shoreline searches. He has also been trained to go into collapsed structures, a specialised skill.

“You think he doesn’t know what the whole thing’s about, but when you’ve been called out, as soon as he puts his jacket on, you see a very different dog.,” said Gayle. “He goes into work mode and switch up a gear.”

Though he has been involved in a lot of callouts, the most memorable for Gayle was the Clutha helicopter disaster in Glasgow, in November 2013.

After a police helicopter crashed into the roof of the Clutha pub, Taz and Gayle were tasked with searching the building for casualties.

Working in cramped, dark and dangerous conditions, they located every victim and assisted with their extraction.

“I have never been so proud of that dog. That’s when you really see the training come to its absolute fore,” concluded Gayle. “We were under a lot of media pressure that day, as was everybody at the site, and I really couldn’t be prouder of him.

“Part of his role is also meeting the public, and certainly after that incident there was a lot of public media interest.

“He turned into a therapy dog for a lot of the families involved. When we met the families who were involved, kids were coming up, talking to the dog and hugging him. I think in a small way, it probably helped them process what happened, what was going on around them. With young families, being in a situation where everybody’s looking at you is quite stressful.

“When you see him work, you just stop and go, oh wow, look at that. He’s just so special.”

People can vote for the dog they want to win by visiting the Crufts website, with the victor receiving £5,000 from the Kennel Club Charitable Trust to donate to a dog charity of their choice and runners-up £1,000.