Rabbits, fungus top Australian invasive species pest list
Four out of five native species threatened by feral invaders, research finds. Nick Carne reports.
Fungi don’t have a reputation as marauding invaders, but they are a serious threat in Australia.
New research ranking the top 10 invasive or pest species in the country has just been released, and coming in at number two is a plant disease called rot root fungus, also known as phytophthora.
The list ranks introduced animal and plant pests according to how many native species they impact. Rot root fungus is bad news for 236.
Two weeds – lantana (Lantana camara) and blackberry (Rubus fruticosus) – also make the list, alongside more obvious bad guys such as rats and feral pigs.
Leading the pack – and this would be no surprise to any Australian – are rabbits. They were brought over when the British first colonised the land down under in the eighteenth century, quickly got loose, and bred like, well, rabbits. They have been present in plague proportions ever since.
“Rabbits destroy plants and can stop them regenerating by eating the seedlings, they compete with native grazing animals for food, and boost the number of predators like cats and foxes,” says Stephen Kearney from the University of Queensland, which conducted the research in collaboration with Australia’s Threatened Species Recovery Hub.
Their findings, which are published in the journal Pacific Conservation Biology, show that invasive or pest species are a major problem for four out of five Australian threatened species – more than 1250 of them in all.
Kearney concedes that foxes ranking as low as six may surprise many, if only because their impact is highlighted regularly in the media. The reality, however, is that feral goats affect more threatened species.
“This does not mean foxes are not a problem, it means there are other really problematic pests out there that as a community we have not been talking about as much,” he says.
The full Top 10, with the number of species they affect, comprises:
1. European rabbit (321)
2. Phytophthora plant disease (236)
3. Feral pig (149)
4. Feral cat (123)
5. Feral goat (116)
6. European red fox (95)
7. Lantana (95)
8. Blackberry (47)
9. Black rat (42)
10. Feral cattle (39)
The Threatened Species Recovery Hub is a collaboration of 10 Australian universities and the Australian Wildlife Conservancy.