Green Gully's Brush-Tailed Rock-Wallabies
Fiona Haddock

A wallaby’s view from the top of a rock-wallaby habitat in Green Gully across to the Aspley River catchment area.

Green Gully is unique. Situated in Oxley Wild Rivers National Park, 20 kilometres south-east of Armidale, its dramatic rock formations provide shelter to hundreds of endangered Brush-tailed Rock-wallabies (Petrogale penicillata). It is for this reason that the Foundation purchased the property with the help of its donors last year.

PhD student Justine Murray recently visited the area to study the wallabies and was amazed by what she saw: “Green Gully blew me away so far as the number of animals. Rock-wallabies were popping up out of everywhere.”

At the first site she visited – considered mediocre habitat – Justine easily observed 20 rock-wallabies, some only metres away. She was also impressed by how healthy they were compared to those in other areas.

With the support of the Foundation, Justine has been surveying the habitats of the Brush-tailed Rock-wallaby (BTRW) throughout southeast Queensland and northeast New South Wales, the stronghold for the national population. Since 2004, she has surveyed 200 sites in Queensland and 268 in NSW. This has been achieved on foot, by vehicle or in a helicopter.

While helicopter trips are expensive, they are well worth it, says Justine. They help to quickly ascertain whether or not a site is occupied by the BTRW and to reach areas that are inaccessible due to the sheer nature of the cliffs. It allowed Justine to view between 20 and 30 sites in a space of three hours – compared to five sites a day.

In the case of Green Gully, Justine took two trips. This involved walking as well as the use of a vehicle. She also took a helicopter ride with the rangers, using her global positioning system to mark where she saw the wallabies.

What’s in it for a brushie?

Brush-tailed Rock-wallabies at Green Gully.

Green Gully’s dramatic rock formations are well suited to rock wallabies. But another reason why the BTRW populations appear so healthy here is due to Green Gully’s previous owner. He was stringent in controlling predators, says Justine, regularly setting baits for foxes and feral goats. He also burnt off stretches of land on a regular basis to ensure the scrub didn’t build up too much.

The problem with feral goats is that they tend to like the same conditions as the wallabies, camping on cliffs and taking the brushies’ spots. Unfortunately, they also have a tendency to reproduce very quickly, often giving birth to twins. “They breed and soon get out of control,” Justine explains.

The problem with foxes is that they can also access rocky climes, putting the wallabies in considerable danger. But at Green Gully, fox numbers have been kept low by the prevalence of dingoes, which the owner allowed to stay. Dingoes don’t tend to prey on the brushies, says Justine, being unable to reach them. “Rock wallabies will only be taken if they’re in the wrong place at the wrong time,” she says. “Wherever dingoes are, rock-wallabies are there. Wherever they get rid of dingoes and bring sheep in, foxes are everywhere and there are no rock-wallabies.”

The NSW National Parks and Wildlife Service is adopting similar methods to those used by the previous owner. Its rangers are actively managing the area, using predator control and fire management and doing annual helicopter surveys to check the rock-wallaby numbers and occupancy status.

While Justine points out that there is no scientific data to support this approach, it does appear to have worked. “In science everything has to be proven,” says Justine, “but it does seem feasible what the previous owner did.”

However, she admits that it is not fool-proof. While fires can help keep scrub down, they also encourage lantana growth – a problem in itself. “There are never clear-cut answers,” Justine says.

Here today, gone tomorrow?

The BTRW in NSW constitute 80% of the national population. “It would take a lot to get rid of them,” Justine says. “There’s a very healthy population.” But there is no room for complacency, she warns. “They’re okay, but you can’t be blasé. There were places I was told they were and they weren’t. If you don’t check on them, you won’t realise they’re gone.”

Justine, who is based in Queensland, says that NSW has benefited from more investment than its northern neighbour. “I was very impressed by NSW parks. There is more funding and it shows. Queensland is struggling with a lack of money - there’s not enough to run vehicles, let alone anything else.”

And Green Gully is a highlight. “I was inspired to think Green Gully could possibly represent what the rock-wallaby populations used to be like,” Justine says. “It has made me realise the importance of maintaining this special area.”

Top of page