Early last week, the young pup, Bruce, ate some white fungal matter, later identified as a death cap mushroom, and became seriously ill before he was taken to an animal emergency clinic.

His owner, Ben Jausnik, thought the dog might not make it and was heartbroken, thinking he might have to have Bruce put down.

Now, Mr Jausnik says "Bruce Almighty" has made a miraculous recovery over the weekend and was allowed home for a visit on Sunday, downing his first full meal and wagging his tail.

"He is alive and wagging his tail. He had his first full meal at home yesterday and rested comfortably," he said.

Mr Jausnik said that while the pup was "not out of the woods yet" and they were waiting on the results of liver tests, the animal was showing positive signs of recovery.

It was a real lesson for dog owners in looking out for the lethal fungi.

"I would hope that poor Bruce's ordeal has helped to save other people and animals from having to suffer through death cap poisoning," Mr Jausnik said.

Bruce's vet estimates the 12kg dog ate two-thirds of a mushroom cap.

The mushrooms have a deadly history in the territory.

Two people died after eating the highly dangerous mushrooms at a New Years Eve meal in 2012, and four Canberrans were hospitalised in April last year after eating death caps.

The ACT's chief health officer, Paul Kelly, warned in early February that wet weather and cool evening temperatures had prompted early blooms in Canberra this year.