Aboriginal hunting practice helps kangaroos
In the depths of the Australian winter, small fires burn through the Little Sandy Desert. These fires are special, lit and controlled by the Martu, an aboriginal group in the Western part of the country.
The Martu burn the grass and brush over small areas of less than 10 acres to look for holes where sand monitor lizards burrow. These lizards are a much appreciated local delicacy and an important source of protein.
This hunting tradition has been practiced for more than a century, and studies show that these fires have ecological benefits. It turns out, hunting fires can actually help boost kangaroo populations by increasing ecosystem diversity and creating a landscape with plants at varying stages of growth.
Kangaroos feed primarily on young shoots which sprout after a fire, but use shrubs to hide from predators like dingoes. By burning small patches, the Martu create a vegetation mosaic that provides both cover and food for the kangaroos.
“It’s critical to have fire, but also to not have too much fire,” Dr. Sam Fuhlendorf, professor of fire and ecology at Oklahoma State University, told TreeHugger. “The neat thing about Australia is that the indigenous people still remember a lot about how they used fire historically. If they burn something every year, they get this shifting mosaic”
The historical basis of the fire burning practice led Dr. Brian Codding at the University of Utah to study how kangaroos and aboriginal peoples may have co-evolved. His study showed that kangaroo populations tend to be larger in areas where the Martu practice their fire regimes. Thus, the Martu play an important role in conservation by maintaining a varied environment in which they live and hunt that benefits kangaroos and other wildlife.
“In some circumstances, humans may modify their environments in ways that benefit endemic species,” Codding told TreeHugger. “People are not actively managing these populations, but because species in this environment are adapted to human disturbance, endemic species do better as a result of human interaction. The Martu are well aware of this.”
Kangaroos are not the only species that benefit from fire. Studies have shown that herbivores like the North American bison are often drawn to burned areas for younger shoots. Researchers like Fuhlendorf, who has been studying fire ecology for over 15 years, suggest that we may want to consider re-introducing fire as a way of boosting land-cover diversity, though he adds that doing so would require further studies on which habitats should be burned and how frequently.
But using fire is considered a double edged sword among ecologists. In many instances, fire is beneficial for maintaining ecosystem diversity, and in most cases all land will burn eventually if left to nature. Periodic fires are important for maintaining many ecosystems, especially grasslands. However, there are concerns about the damage that burning practices can have on other species.
“Generally, large scale burning is increasingly seen as an ecological disaster because it opens up the ground cover and greatly exposes small and medium vertebrates to predation by dingoes, foxes and feral cats,” Dr. Terry Dawson, who studies environmental physiology and arid zone mammals and birds, told TreeHugger.
There are indications that other animals like sand monitor lizards, bushtail possums and hare-wallabies also benefit from Martu fires, so there are clear benefits to periodic burning.
“Like all things in ecology, there are tradeoffs – winners and losers,” said Dr. David Bowman, professor of environmental change biology at the University of Tasmania. “There’s an enormous debate in Australia about the frequency and scale of burning the savannah environment, and there are potential carbon implications, but the fact of the matter is that, again, it’s a tradeoff. They’re naturally going to burn, so planned burning can reduce the [negative] impact.”