The red-necked wallaby is easily recognized by its striking patch of rust-colored fur, which gives it its name.

In 2023, the Manx Wildlife Trust conducted drone surveys that pinpointed 568 feral wallabies residing in Ballaugh Curragh, a protected marshland on the Isle of Man.

“I suspect there might have been some oversight in earlier counts, or we’re witnessing a significant population surge over a brief period,” an observer noted.

Back in 1965, Curraghs Wildlife Park saw its first escapee when a wallaby named Wanda broke free during the park’s inaugural year. Although Wanda was eventually captured and returned, local reports indicate that several more wallabies managed to escape in the following decade.

Today, there are more than 100 species at Curraghs Wildlife Park, including red pandas, penguins and a population of Australian wallabies. Credit: Curraghs Wildlife Park

The exact number of escapees is unconfirmed, although the gene pool within the population is likely narrow.

Archer believes crop damage and the risks associated with inbreeding are key concerns for farmers.

Simon Archer said one of the best-preserved medieval castles in Europe is right on his doorstep. Credit: Simon Archer

“There is a danger that you’re going to have quite ill wallabies wandering around the place … and farmers with livestock understand what that can mean for their animals in the future,” Archer said.

‘Quite damaging’

The wetlands are known for their bog pools, birch scrub and grey willow — called “curragh” by locals, from which the area takes its name. With mild winters and cool summers, the habitat also resembles parts of Tasmania, which is where the red-necked wallaby originates.

What to do?

“I think we need to close these kinds of knowledge gaps, answer the questions that we have, before we make a statement either way,” he said.

Feral Australian species elsewhere

“It’s so difficult to put genies back in bottles. With globalisation, people buying things overseas, going overseas a few times a year, it’s [biosecurity threats are] just exploding,” he said.

Detector dog teams intercepted more than 42,000 high-risk items, including at Australian airports in 2024. Source: AAP / David Jones

The Department of Defence has a budget of almost $60 billion a year. Comparatively, funding for biosecurity is $935 million, which is expected to decline to $889 million in 2028–2029, according to the Australian Department of Agriculture, Fisheries and Forestry.

“I mean, it’s not a sexy issue,” he said.