Climate change is killing the plants of Uluṟu-Kata Tjuṯa. Aṉangu traditional owners are concerned

When we hear that climate change is damaging natural environments, it conjures images of rising seas eroding coastlines, or heatwaves bleaching the Great Barrier Reef. But what about deserts?

In Australia’s red heart, the World Heritage-listed Uluṟu-Kata Tjuṯa National Park hosts a spectacular array of unique plants and animals, admired by visitors from around the world. This week marks the 41st anniversary of the official handback of Uluṟu-Kata Tjuṯa to Aṉangu, its traditional custodians.

As joint managers of Uluṟu-Kata Tjuṯa with Parks Australia, Aṉangu bring tens of thousands of years of accumulated knowledge to caring for these lands. But lately, the local plants – and the animals that depend on them – are dying.

Aṉangu Muṯitjulu Mala Ranger Natalie Ray explains:

When we go out to look around, we see the numbers going down. We don’t know what’s going on in other places in Australia or around the world, but we can see our plants and animals suffering.

What is climate change doing to this special place?

Drought and soaring temperatures

Between 2018 and 2021, the most severe drought on record unfolded at Uluṟu-Kata Tjuṯa. While there are earlier records of very severe droughts – in the 1880s and mid-1950s to mid-60s – there is a key difference. Temperatures this century are much higher, bringing longer, hotter and more frequent heatwaves than any other period in recorded human history.

These hot droughts pose a serious risk to plants. Following record-breaking heatwaves in 2019-20, Aṉangu witnessed mass mortality of usually robust plants such as kurkaṟa or desert oak, Allocasuarina decaisneana, wanaṟi or mulga, Acacia aneura, and pukaṟa or desert heath myrtle, Aluta maisonneuvei.

In 2020, Parks Australia and the Aṉangu community held a workshop to talk about climate change, and concerns were raised about the effects of hot droughts. Since then, Aṉangu have been working with scientists from Parks Australia, CSIRO and a range of universities to determine how climate change is affecting plants at Uluṟu- Kata Tjuṯa. The Muṯitjulu Mala Rangers have been an important part of this partnership.

As Anangu elder Malya Teamay from the Muṯitjulu community has said:

We’re worrying about this a lot […] we’re here on Country and we can see that things are getting really bad.

Some plants coped better than others. Why?

Using novel 360-degree imaging, scientists and Muṯitjulu Mala Rangers found that plant dieback – characterised by the death of leaves, shoots or roots – covered hundreds of square kilometres within Uluṟu-Kata Tjuṯa National Park alone. Aṉangu and researchers co-designed and conducted a series of linked research projects to understand whether different plant species coped better than others. If so, why?

Following the hot drought, detailed on-Country surveys undertaken with Aṉangu found plant species had died at different rates. While 78% of kurkaṟa had survived, only 10% of pukaṟa had survived. Our most recent research, published this week, suggests that how plants use water during a drought might explain why some desert species are more likely to die than others.

We found that species with low rates of dieback tended to slow their growth and conserve water in their tissues. Those more likely to die were species that continued to use water for growth during summer, a strategy that might work in mild drought, but can lead to rapid water loss and death by dehydration during severe drought.

As Aṉangu Muṯitjulu Mala Ranger Michael Swan says:

We’ve been out here observing and learning, working with scientists, seeing that so many of our trees here are dying off. This is happening here at our home, Uluṟu, Muṯitjulu. We have to take care of our Country.

Profound consequences

Aṉangu are concerned about what the mass death of plants means for their land. When certain native plants die, it clears a path for other species, often with profound consequences. The invasive weed buffel grass, Cenchrus ciliaris, is spreading rapidly through Uluṟu-Kata Tjuṯa, crowding out native plant species and choking waterholes.

Animals dependent on native plants are also feeling the heat, with Aṉangu observing hardy desert lizards dying and birds dropping from trees during extreme heatwaves.

Aṉangu are using these shared research findings to inform the management of Uluṟu-Kata Tjuṯa under increasing climate extremes. But the problem can’t be tackled alone: Aṉangu, scientists and governments must work together.

As Aṉangu Muṯitjulu Mala Ranger Natalie Ray says:

We feel that the changes need to be happening right now, that this air pollution has to stop for the sake of our children and the generations to come, so that the Country can remain healthy and strong for them too.’

Many representatives of the Mutitjulu Community and Muṯitjulu Community Mala Rangers have been actively collaborating in this research. This research was largely funded by Parks Australia, with substantial in-kind contributions from CSIRO, University of New England, The Australian National University and University of Technology Sydney.