New Zealand conservationist Pete Bethune thought he 'was a dead man' after horrific Costa Rica snake attack

New Zealand conservationist Pete Bethune thought he "was a dead man" after being bitten by central America's most deadly snake while out in the Costa Rican wilderness.

He was hospitalised in late December and the 55-year-old was only discharged on January 10.

Bethune, the founder of Earthrace Conservation, assists countries across Asia, central America, and Africa with fisheries enforcement and anti-poaching efforts.

Speaking to The AM Show on Tuesday morning, he said his first few days in the hospital were a blur.

"I've still got some complications now - I just got the catheter removed a few days ago. I'm back to pissing properly so that's a good sign," he joked.

While recovering well, Bethune said his leg remains swollen.

"I'm just working on that over the next month or two to try and get the swelling down."

After the attack, Bethune had to navigate treacherous terrain to get out of the jungle as his life hung in the balance.

"They [doctors] reckoned if it was an hour later I would have been dead," he said. "It was a close call in terms of timing but there is a degree of luck involved - it depends where the snake bites you. If it comes very close to an artery or a significant vein, it's worse."

He said being relatively fit and healthy may have helped his cause.

"The hospital staff here get a lot of snakebites so they know exactly what to do - I'm a very lucky man.

"I might have a hole in my leg and my leg's not so pretty anymore, but that's okay - I'll settle for that."

The father-of-two concluded by saying he felt blessed to be able to his job but acknowledged the risks that came with it.

Bethune was bitten by a fer-de-lance, a highly venomous pit viper considered the most deadly snake in central America. He's had several brushes with death, including in 2017 when he survived a stabbing attack while on a mission to fight poachers and loggers in Brazil.