Several hundred feral goats have been removed from the Belair and Onkaparinga River National Parks, leaving them apparently goat-free for the first time in many years.
Intensive operations used monitoring cameras, trapping yards, ground shooting and Judas goats. Park rangers removed what they believe were the final remaining goats over the past few months.
Wild goats are a significant threat to biodiversity because they graze heavily on native vegetation, cause erosion and spread weeds. They also open up dense areas of vegetation that protect smaller native animals and birds, leaving them vulnerable to foxes and feral cats. There had been some community concern about the environmental damage and possible safety risk posed by large groups of goats in both parks.
The sustained effort was needed because goats move freely through steep and rocky terrain as well as dense vegetation, and can split off into a number of smaller groups. At Belair their activity also threatened the vulnerable Leafy Greenhood Orchid.
The operation in both parks involved a partnership with volunteers from Sporting Shooters’ Association Australia - Conservation and Wildlife Management (SA) Branch, who were responsible for the majority of the goats removed and spent many hundreds of hours in the parks. Rangers working as part of AMLR’s Regional Grazing Pressure Management Project removed the last goats recently.
The management project was established late last year to reduce the impacts of large herbivores, including goats, fallow deer and western grey kangaroos, across the region. It will coordinate efforts in parks and on other land with work by private landholders and other government agencies.
Acting senior ranger Brent Lores said more than 90 goats had been removed at Belair, where numbers swelled after about 10 were illegally dumped in 2014.
“Feral goats fragment the landscape by forming tracks through bushland. As they travel they eat everything in their path, so you end up with large areas completely denuded of vegetation,” he said.
“Targeted ground shooting operations were used in addition to extensive trapping. Some animals were caught by placing a water trough in a temporary yard, which attracted them so we could trap them. This proved highly effective in hot weather.”
Remote cameras helped record the location and number of goats, while a Judas goat fitted with a tracking collar provided information on their movements.
”Eradication isn’t always a realistic goal when it comes to feral animal management, but in this case we always believed it could be achieved as we were dealing with what was essentially one isolated population. As a ranger it is fantastic to be able to achieve something that has a tangible positive impact on the biodiversity that we aim to conserve within the park,” Mr Lores said.
Senior ranger Steve Johnson said at least 100 feral goats had been removed from Onkaparinga River National Park over many years. Populations are believed to have established after goats escaped from holding yards at a former meatworks several decades ago.
“Some sensitive land above steep rock faces was bare of ground cover and understorey due to the goats’ intensive use,” he said.
Ground shooting and Judas goats were the main methods used at the park.
Mr Johnson said a nationally endangered grey box woodland community would benefit from the removal of the goats, along with a range of other plants and animals, as would revegetation plantings by Friends of Onkaparinga River Park volunteers.