London: The Argentine ant, one of the world`s worst invasive species, invaded New Zealand 20 years ago -- but is now disappearing without any human intervention,
The Argentine ant (Linepithema humile) marched across the nation`s two main islands. Dealing with the pest was projected to cost NZ dollars 68 million every year. Perhaps no longer.
A team, led by Phil Lester at the Victoria University of Wellington, has carried out a research and found that alien ant colonies in 60 locations are collapsing on their own, the
`New Scientist` reported.
Lester thinks low genetic diversity, which is associated with reduced disease resistance, is the most likely reason for the ant`s demise.
Lori Lach at the University of Western Australia, Perth, warns that other alien species won`t be so easily dealt with.
"For thousands of other invasive species around the world we have seen no such collapse," she said.
The findings have been published in the `Biology Letters` journal.