Rabbits Are Australia's Biggest Threat to Native Wildlife. Why Are Their Numbers Booming Again?

Rabbits are taking over parts of Australia, and scientists are very concerned. After a wet winter, rabbit populations have grown fast in many areas. Experts say two things are to blame: good rainfall that helps rabbits breed quickly, and rabbits becoming resistant to the viruses used to control them. This is bad news for Australia's native animals, which already struggle to survive alongside these invasive pests.

A dog named Jojo is helping fight the problem at Bon Bon Reserve in South Australia. She is a five-year-old mix of kelpie, Jack Russell, and whippet, working eight days on and two days off. She runs up to 20 kilometres a day chasing rabbits back into their underground tunnels, called warrens. Her work helps staff find and map the warrens so they can be destroyed or sealed off.

Scientists have spotted rising rabbit numbers in many parts of the country. These hotspots include southern Western Australia, the suburbs of Canberra, areas near Adelaide, and parts of Queensland and New South Wales. In the town of Albany, Western Australia, rabbits reached what experts call plague levels, invading farms and a top golf course. Staff at the golf course reported up to 30 rabbits gathering on the greens each evening, digging holes and wrecking the grass.

European rabbits were first brought to Australia in 1788, but scientists say the real population explosion began in 1859. That year, a settler named Thomas Austin released just 24 rabbits onto his property. By the 1920s, there were billions of rabbits across the continent. Today, the population is estimated at around 200 million, though there is no official system to count them.

Rabbits cause enormous damage to the environment. One study found they negatively affect 329 threatened species in Australia — more than any other invasive pest. They eat the shoots of native plants and compete with native animals for food and space. They also attract feral predators like cats and foxes, creating what experts call a triple threat to native wildlife.