SNIFFER dogs, traps and chemicals have all been used to try to reduce the cane toad colony at Taren Point.
Now scientists from the University of Sydney are proposing to pit cane toad against cane toad in the latest attempt to eradicate their presence from Sutherland Shire.
Sutherland Shire Council is providing $60,000 in funds to support the work of Rick Shine and Matt Greenlees of the biological sciences department at the University of Sydney to tackle the shire’s cane toad invasion.
The university and council staff have already conducted a considerable body of work at the remote Taren Point cane toad colony, including the use of cane toad sniffer dogs, traps and mustering the community to manually remove the toads.
But the spread of cane toads is continuing to the shire’s south, despite the cooler conditions, which are different to their original tropical environment.
The cane toads can be lethal to the shire’s native species and can kill large predators, such as goannas, quolls and freshwater crocodiles, according to the university’s research.
The university program at Taren Point has restricted their dispersal area into adjoining wetlands and conservation area.
In the latest development, the university researchers have identified a new chemical as effective in controlling cane toad populations.
A paper by Professor Shine and Dr Greenlees said the chemical was produced naturally by cane toad tadpoles to kill newly-laid cane toad eggs and reduce competition.
Professor Shine and Dr Greenlees outlined their findings in the paper, ‘‘Using the cane toad’s own weapons for invader control’’.
‘‘The biological explanation for the evolution of this toad-killing chemical is competition between toads,’’ they said in the paper.
‘‘By killing any newly-laid eggs, older toad tadpoles avoid having tens of thousands of additional hungry mouths competing for food in their home pond.
‘‘Clearly, we might be able to turn the toad’s own weapons against it.’’
Trials show the chemical has no effect on the eggs of native frogs or other species.
The university is applying for $600,000 from the Australian Research Council to fund field trials, to which the council will contribute $60,000.
Any chemical would have to be of no risk to native fauna.
The council was first informed of the presence of cane toads in the shire in 2008 and they have been spotted as recently as May.
What do you think can be done to eradicate the shire’s cane toad problem?
