Wild horses once roamed freely on this island. Their removal has seen the boom in native species

For residents of Curtis Island, off Queensland’s central coast, it’s not uncommon to see wild horses roaming the beach, bushland or even the streets of the tiny township of Southend.

“For us, they are an integral part of the island,” Kerry Freney said.

“You have the ocean, you have the landscape, the beaches, and you have the brumbies and the roos.”

While striking to behold, the horses are part of a wildlife problem on the southern island of the Great Barrier Reef, according to the Queensland Parks and Wildlife Service (QPWS).

“Wild animals are causing significant damage to key habitats, critical species, such as the yellow cat and flatback turtles,” said Damon Shearer, senior officer of the QPWS Capricorn Coast Management Unit.

While some horses remain on the island, around 15 miles off the coast at Gladstone, their numbers have dropped significantly since a wildlife control program was introduced.

A Department of Environment and Science (DES) spokesperson said wild animals including horses, cats, foxes, dogs, pigs and cattle spread diseases and weeds, trampled vegetation, damaged wetlands and preyed on a range of native wildlife, including turtle claws.

They said the control program involved aerial fire, which was carried out by experienced staff from helicopters.

The spokesperson added that QPWS “complies with standard operating procedures and codes of practice to ensure compliance with animal welfare requirements” and that the public was informed before the shootings took place.

“Amazing Metamorphosis”

Mr Shearer said the removal of wild animals had produced “phenomenal results” in restoring the island’s diversity of flora and fauna.

Over the past four years, rangers have noted a significant increase in the population of endangered Capricorn yellow cats after the removal of the hoofed animals led to significant vegetation regeneration.

DES research shows that the species’ population had fallen to single digits on the island between 2005 and 2011 due to the impact of wildlife and the ongoing drought.

But the Yellow Cats recorded their highest number in the 2021-22 record period at 73.

“The pigs were doing an incredible amount of damage to the reedbeds in the north, which is critical habitat for the yellow cat,” Mr Shearer said.

“Almost every year this area was turned upside down and it was just turned into mud.

Department research also shows that there has been minimal brood loss of flatback turtles to predators such as foxes, feral dogs and feral pigs with QPWS targeted pest control.

Education key to understanding

While some people on Curtis Island support the pest control program, others would like to see the animals left alone.

Linda Strickland has been coming to Curtis Island since she was a teenager and has fond memories of the horses that roamed the town.

“Some of the wildlife should be left alone; the brumbies and cattle, we had a lot of cattle,” Ms Strickland said.

“I don’t really think it’s as big an issue as what [QPWS] make believe that is the case.”

Justine Shaw from the Queensland University of Technology works on the ecology and management of Antarctic and island ecosystems, and said while removing invasive species could be controversial, there were major long-term benefits.

“Nobody likes to see animals being killed, and that’s one of the challenges of culling invasive species,” Dr Shaw said.

“One of the things that helps people understand the benefits of these controls is that we’ve seen in many other islands in Australia and around the world that if the commitment is made to get rid of these invasive species, the benefits for the natives the animals and the vegetation are enormous.

“It’s really important that we don’t lose sight of the final price.”