We needed a quick learner; one small enough to fit into the nooks and crannies cats hide in. Mostly, we needed a dog with no desire whatsoever to chase cats

Molly is the world’s first trained cat detection dog. Her job is to rescue missing moggies. We had been looking for a dog with a particular temperament and intelligence to join our team of pet detectives for 18 months. We had scouts out and had spoken to the country’s top breeders.

We needed a quick learner; one small enough to fit into the nooks and crannies cats hide in. Mostly, we needed a dog with no desire whatsoever to chase cats.

I came up with the idea in 2014. I had been doing the job for 20 years and my business, Pet Detectives, was getting around 30 calls a week about missing cats. When cats go to ground, they go into a comatose-like state and if they are not found quickly, within a fortnight, they often don’t survive after being rescued.

One particular couple who called me had bought their cat after struggling to have children. We found it in a neighbour’s garden shed, but it later died. Seeing them so bereft was a tipping point for me.

I worked in the police as a detective inspector for many years, and had seen dogs search for drugs and bombs and help with murder investigations. I figured, if a dog can be trained to find amphetamines, then it can be trained to find cats.

We found Molly, an 18-month-old black-haired cocker spaniel, on Gumtree. She was a giveaway. The ad said: “Needs a good home, cannot cope.” If cocker spaniels are not stimulated they become uncontrollable. She had been passed from pillar to post and had three owners in under two years.

I first met her in February 2016, at the home of Medical Detection Dogs, the charity that would help train her. We had already rejected 12 dogs without seeing them. Three others didn’t make it through initial training: one was too timid, one got car sick and the other was too inclined to chase.

At first, Molly was anxious. But she had intelligent eyes and was a problem-solver. She was also hyper and fixated on catching tennis balls. She had the right temperament: a bright working dog from a breed with a natural disposition to search for game. We just had to channel that instinct into finding cats.

She had to be “cat-tested”, so we took her to a farm with a dozen cats to see if she would chase them. She didn’t even bark. Her focus was on interacting with her handler.

Her training took nine months with experts, including two doctors of canine behaviour. This had never been done before. She was a quick learner. The first phase was lab training, where we taught her to isolate scents. She then worked with a behavioural specialist who taught her to understand signals and commands. The final stage was teaching us to work together.

On assignments, Molly is trained to pick up cats’ scents from their bedding. When she finds the missing cat, she lies down to signal success, so as not to scare them, but you can see her trembling with excitement. She gets rewarded with her super-treat: black pudding.

Her first success was in February this year. A tri-coloured moggy had been sighted six miles from home on the roof of a garden shed. Molly quickly picked up her scent on the grass. I sent her across the back of 30 gardens until she started clawing at a fence. She charged across the lawn to a summer house and lay down. The cat was inside. The owners were over the moon and quite amazed by her.

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Molly has helped to rescue 11 cats so far, and our search success has increased by a third. She wears a fluorescent harness and has her own abseiling kit, which we once used to lower her over a 10ft wall. We’re getting special boots made to protect her feet in outbuildings where there may be nails or glass.

Many people said that training a dog to rescue cats was crazy; that all dogs chased cats and it couldn’t be done. Nothing has felt quite so rewarding as seeing it work. People are fascinated when they watch Molly at work, but she’s not fussed. She still doesn’t know that those things with four legs that she searches for are called cats. To her, it is just her favourite game.

• As told to Deborah Linton

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