A 44-year-old trekker was forced to eat his own dog while stranded in the wilderness just days after his beloved companion saved him from a black bear attack.

Marco Lavoie killed and ate his German shepherd after a bear destroyed his food supply and vital supplies more than 800km out of Montreal, Canada.

According to Canadian news agency QMI, the dog chased off the bear but was killed with a rock by a desperate Lavoie.

A spokesperson for local authorities reportedly said his first words after being found were: "I want to get a new dog."

View photos The explorer was stranded alone for nearly three months and was found 'close to death' by rescuers on Wednesday. Photo: Supplied. More

"He is very ill and he can barely talk, but when our officers spoke to him in hospital the only thing he said was, '

I want to get a new dog,'" said Richard Carbanneu.

"I suppose he must feel very guilty about eating his pet, it is obvious he loved him very much and did not want to do what he did."

View photos FILE PHOTO: Adult male black bears can weigh up to 250kg. Photo: Getty. More

He joined other survivalists praising Lavoie's 'brave' decision to sacrifice his beloved companion in a bid to survive.

"He was alone in the wilderness with no food for weeks. He had badly hurt his ankle as well, so he could not hunt for food. I suppose he thought he had no choice," he said.

When Lavoie was rescued by helicopter, he had lost over 40kg and was suffering from hypothermia.

He remains in a critical condition in a northern Quebec hospital.