"You can smell it."

One memory Kai Wild can't shake from the time he spent on Kangaroo Island earlier this year is the smell.

The 35-year-old tree surgeon says you can be standing in a burnt area, but it's not ash or physical destruction that gives it away. It's the smell of dead wildlife.

Kai's story went viral in February when he started to document his days rescuing koalas during Australia's horrific bushfire season. Hearing from a friend of a friend that they needed a tree climber on Kangaroo Island, the conservationist got in his car and drove 1,500 kilometres to volunteer. There, he rescued over 100 koalas in a matter of weeks, and connected with tens of thousands of Australians via social media who felt helpless as the fires raged on.

It's estimated that at least half of the koala population on Kangaroo Island perished during our most recent bushfire season. But for those who followed his story, Kai and his koalas weren't synonymous with tragedy. Instead, his work was a reminder of the impact that one individual can have when the unprecedented happens.

Speaking toMamamiaabout his decision to drive to Kangaroo Island - on nothing more than word of mouth - Kai says, "I had wanted to be able to help the entire fire season".

Earlier in the year he had been deployed with the SES to south New South Wales, but it was the specificity of what Kangaroo Island needed that motivated him to go on his own. "When someone says they need a tree climber, that’s something I know I’m able to do," he says.

What followed was weeks of 10-12 hour days, where he was by himself a lot.

The impact of his work, however, was seen and felt by many. At the Kangaroo Island Wildlife Park, koalas were everywhere. Makeshift beds were made from laundry baskets and towels, as vets and rescue workers did all they could to nurse the injured wildlife back to health.

Their fate was a reality Kai had to somewhat disengage from.

"If you become invested [in the fate of the koalas you rescue] you run the risk of them not surviving," he says. "All these other people are also invested in this koala… and for that koala to then die, you feel the responsibility to be honest with people about that."

For Kai, however, there was one exception. A female joey.

On February 4, Kai filmed an emotional video of himself finding a little joey by itself with severe burns. She was the first burnt joey he had found, with a burnt nose, singed face, and singed body. But upon rescuing her, he immediately felt a connection, and nicknamed her Joey Kai.