'A billion animals gone' — understanding the effects of Australia's fires on wildlife and people

When Valentina Mella looks out the window of her Sydney home, she's horrified at what she sees.

"To be honest with you it's literally like an apocalypse," Mella told Quirks & Quarks host Bob McDonald.  "People don't know if it's day or night and this red smoke and sky near the ocean. It doesn't even look real. It looks like one of those Hollywood movies."

Since October, Australia has been battling massive, unpredictable bushfires. So far, 27 people have been killed and 103,000 square kilometres of land have burned. More than a billion animals are feared dead.

"I think that's actually a conservative estimate," said Mella, an ecologist with the University of Sydney. "What we are seeing is a lot more has been lost."

It was Mella's colleague Professor Chris Dickman who initially suggested 480 million animals had been killed, and then revised that to over a billion. 

"The estimates don't account for all the invertebrates that we might have lost, which is a really important part of the biodiversity because a lot of animals eat insects. And so once those insects go, the animals that survive will not have any food left to eat," said Mella.

"It will take years to get the habitat back where it should be for animals to survive properly in it."

Wildfires "wreak havoc throughout the body"

It's not only the animals that face lasting effects from these fires.

"In Australia where there's been smoke exposure up to 12 times the limit that's deemed hazardous, that's much higher than anything that we've seen here in California," said Mary Prunicki, the director of Air Pollution and Health Research at Stanford University.

"And also they're having this exposure for an extended period of time, the damage to human health is going to be much more severe unfortunately and much worse."

Prunicki studies the health effects of wildfires on children in the California area. And what she's found is that exposure to wildfire smoke can not only lead to increases in cardiovascular diseases and respiratory disorders like asthma, bronchitis, and pneumonia, it can even change a person's DNA.

"Wildfire smoke consists primarily of particulate matter," she said. "About 30 times smaller than the width of a human hair. So very very small particles that are so small that when you breathe them in, they can cross over into the bloodstream and then go throughout the body causing inflammation in lots of different organs and wreak havoc throughout the body."

Researchers won't know the true lasting effects of the devastation until the fires stop burning. 

"I don't even want to think about it to be honest because it is so tragic," said Mella. "Australia is a country that burns up naturally quite often, but nothing like this to this extent." 

"Nothing can survive this, it's just hell."