‘Citizen Scientists’ Pitching In To Help Save Our Koalas
July 29, 2014

Australian Citizens Are Helping To Save Koalas

NERP Environmental Decisions Hub

Australian citizens are pitching in to help save the koala, one of our most iconic and vulnerable species, environmental scientists say.

By linking the public’s sightings of koalas with changes in the landscape and climate, scientists from the National Environmental Research Program’s Environmental Decisions Hub (NERP EDH) have quantified how many threats affect koala populations in New South Wales (NSW) and have identified the impact of these threats across the state.

“Using data collected through citizen science projects, we found that koalas in the west of NSW are substantially more at risk of decline compared with those in the east of the state,” says Dr Jonathan Rhodes of NERP EDH and The University of Queensland. “The major threats to koalas are the loss of forest combined with drought and higher temperatures. In the east, the major threats are associated with forest loss and urban development.

“In Eden, NSW, for example, climate, fire and human population growth have combined to cause the local koala population to decline significantly over the past 35 years.”

Currently, koalas are distributed widely across eastern Australia, Dr Dan Lunney of the Office of Environment and Heritage NSW explains. While this reduces the chance of the species as a whole going extinct, it also means that the animals are spread across a wide range of different lands, climate zones and vegetation types.

“So they’re exposed to different threats in different places, and this makes it incredibly difficult to plan for their recovery because we can’t apply a ‘one-size-fits-all’ strategy. The challenge, then, is to identify the key threats that are driving the decline in a particular area,” Dr Lunney says.

In their study, the NERP EDH researchers used state-wide surveys that asked the NSW public whether koalas were present where they lived. “We already had data on the changes in forest cover, climate, rainfall and other factors,” says Dr Rhodes. “What we needed were the location and the number of the koalas, and this was difficult to assess because of the large areas involved.

“This was where the general public came to the rescue and made the study. They have provided a wealth of information on the distribution of the koalas, and because the surveys were carried over time in 1987, 2006, and 2011, we were able to construct a timeline and map the changes over the years.”

The researchers also used the information to predict the distribution of koalas in NSW in the next decades. The predictions show that koalas are currently distributed in low density populations in the west of the state, but the population will likely contract further towards the coast if there are no plans for their recovery.

Dr Rhodes says that this work underscores how important citizen-collected data can be to the nation’s efforts in saving its precious biodiversity: “If we had to rely only on our own field-based data, our information would have been very limited."

Apart from collecting data, citizen scientists can play other roles to boost the survival of the endangered species, he adds. “Since koalas depend on eucalyptus leaves for food, the public can help plant more of the right trees. They can also raise awareness in their local communities and help develop action plans to save the koalas in their neighborhood.

“Also, people should drive carefully to avoid hitting koalas, and know where their dogs are at night to prevent them from attacking native animals.”

The study, “Modelling species distributional shifts across broad spatial extents by linking dynamic occupancy models with public-based surveys” by Truly Santika, Clive A. McAlpine, Daniel Lunney, Kerrie A. Wilson and Jonathan R. Rhodes, was published in Diversity and Distributions.

The study “Extinction in Eden: identifying the role of climate change in the decline of the koala in south-east NSW” by Daniel Lunney, Eleanor Stalenberg, Truly Santika and Jonathan R. Rhodes, was published in Wildlife Research.

The Australian Government funds the National Environmental Research Program (NERP) to inform evidence-based policy and sustainable management of the Australian environment.