An infestation of ants which is attacking numerous animal species in Australia is threatening to spread across the country, scientists have warned.
Described as one of the world's most vicious species of ant, the yellow crazy ant sprays formic acid into the eyes of other animals, leaving them vulnerable to attack and unable to feed themselves.
The ants have already wiped out up to 20 million red crabs, as well as birds and other animals on Australia's Christmas Island in the Indian Ocean since 1989, and have since spread to 63 locations in the Northern Territory on the mainland.
YELLOW CRAZY ANTS
So named because of their
erratic behaviour when a nest is disturbed
Originally from India
Canberra's Commonwealth Scientific and Industrial Research Organisation (CSIRO) warned on Friday that, if left unchecked, ant populations would proliferate across Northern Australia and beyond.
"It is simply a matter of when will it happen," said CSIRO researcher Ben Hoffmann.
This little yellow crazy ant will destroy our culture, our land, our life
Aboriginal ranger Balupalu Yunupingu
Mr Hoffmann said the ants' victims died, not from the attack, but from starvation because they were blind.
The CSIRO, in association with two Aboriginal land management groups, is developing a three-year plan to wipe out a large infestation centred on a 90-kilometre (56 mile) radius around the mining town of Nhulunbuy, on the north-eastern tip of the Northern Territory.
Mr Hoffmann said yellow crazy ants formed multi-queened "super-colonies" in which ants occur at extremely high densities over large areas.
"The density of foraging worker ants in super-colonies is amazing, reaching around 1,000 per square metre or 79 million per hectare of bush," he said.
Once a super-colony is established, it can expand rapidly, growing around its edges by some three metres (10 feet) per day or one kilometre (more than half a mile) a year, he said.
Originally from India, the crazy ants are believed to have been introduced to Australia about 60 to 70 years ago.