Mr Clarke lured the pure-bred dingo mother into a rubber-lined steel trap at Tidbinbilla, then her father, a notorious sheep killer, and all five siblings.

Mr Clarke discovered her about two kilometres from where the others were caught west of Canberra, getting into a paddock full of lambs.

Realising she had more go in her than the others, he trapped her and spared her life.

Now calledJess, the dingo doesn’t like to be patted. She doesn’t bark. She eats chicken and rabbit but won’t eat lamb. She hates being inside.

When Mr Clarke camps at a ranger’s hut in the mountains he has to sleep outside, otherwise Jess will howl until he comes outside. She digs a hole and sleeps nearby.

"She can tell me just about every thing about a dog," Mr Clarke said.

"She sniffs around, if it’s fresh the hair will go up on her back. She’s got the best nose on a dog I’ve ever seen.

"She’ll drag me 50 metres into the bush and there will be a bloody big dog turd sitting on a tussock, or something.

"So you set a trap and nine times out of 10 she’s right."

Jess is on a long chain because she doesn’t come when called.

In the back of Mr Clarke’s truck, she stares out quietly into the bush.

It’s only when he stops to point out five wild dogs in a paddock at Gudgenby in Namadgi National Park that Jess howls, lifting her faded ginger jowls towards the other dogs and white tufts of mist on the purple mountains beyond them.

Becoming the alpha male in her life has lead Mr Clarke to realising he will never again train a dingo because of the commitment they expect in return.

"Soon as I am out of sight, she whinges. I haven’t been able to go on holidays - unless I take her with me.

"If I eat anything, she expects me to give her some. She whinges if you don’t share."

But Jess’s urine is worth bottling.

A few drops on a tussock or rock on the edge of a fire trail has lured wild dogs into Mr Clarke’s traps. Her droppings are handy for the same reason.

Mr Clarke is the sole ACT Parks and Conservation Service trapper helping maintain a largely dog-free area near grazing land adjoining national parks.

Wearing shorts throughout the year, no matter if it’s brumbies he’s trapping in the snow or feral cats in spring, his job is relentless. He checks daily 60 traps along boulder-strewn trails, dry creek beds and thick forests.

Trapping for 35 years after learning from his rabbit trapping father, the challenge still drives him.

"I’ve been after a bitch for three years," he said, heading into Gudgenby before dawn.

"I came close near Tharwa. I’ve caught her pups. She’s eve stepped on the (trap’s) plate. She’ll slip up one day.

"But you’ve got to admire her, she’s bloody smart. It’s almost sad, really, when you catch them - it’s like an end of an era."