Australia's Bush Fires Help Kangaroos Survive

A new study suggests that bush fires, set-up by aborigines, help increase kangaroo numbers.

Australia's Aboriginal Martu people have been ritually setting small fires to expose lizards for the past 2,000 years. A new study by the researchers at the University of Utah has found that the fires actually benefit kangaroos and other species in the region.

At first, it might seem counterintuitive that hunting and setting up bush fires can help kangaroos survive. However, researchers discovered that these small fires lead to a "mosaic of vegetation." These post-fire plants help sustain large populations of kangaroos.

Also, research has shown that small, man-made fires prevent large blazes by natural causes.

The latest study found that fires created by Martu people lead to five different stages of vegetation. The distinct pattern of plants helps kangaroos survive. For example: the tall, unaffected grass helps the marsupials hide from predators, while the short, new shoots that grows post-fire provides nourishment for the animals. The researchers found that populations of kangaroos were largest near Martu settlements, despite the fact that these people kill the marsupials for meat.

The study doesn't mean that killing kangaroos helps the population grow, but suggests that ancient hunting practice creates an environment where kangaroos and humans can survive together.

Earlier research has shown that fires set by the Martu hunters increase sand monitor lizard populations. These fires also benefit other mammals such as brushtail possums and hare-wallabies.

"When subsistence practices have long histories, they are more likely to sustain ecosystem stability," Brian Codding, an assistant professor of anthropology, said according to a news release. "But when there are sudden changes to the way people make a living on the land, expect the result to be detrimental to the environment."

"In some parts of Australia where Aboriginal people no longer are burning the bush, ecologists are recording rapid declines in threatened species, which also might be due to increased predation by invasive predators," Codding added.

The study is published in the journal Human Ecology.