NT: Cane toads' damage to Kakadu still anyone's guess

AAP General News (Australia)
12-30-2001
NT: Cane toads' damage to Kakadu still anyone's guess

By Rod McGuirk

DARWIN, AAP - As toxic cane toads flourish in Kakadu National Park during the current
wet season, scientists can only guess the long-term damage to Australia's premier World
Heritage-listed wilderness.

The long-dreaded arrival of the Venezuelan invader in Kakadu was confirmed in March
towards the end of the last wet season.

The advance slowed during the dry season but with the return of the monsoonal rains,
the toads are consolidating their hold on the park faster than most experts had predicted.

Public outcry over an unstoppable menace to Kakadu combined with the partial sale of
Telstra provided the impetus for the latest government effort against cane toads.

A year ago - only three months before the first toads were discovered on Kakadu's southern
boundary - the federal government turned on the funding tap in a renewed bid to stop the
65-year-old advance.

It promised the CSIRO $2 million of Telstra II booty from the Natural Heritage Trust
over two years to invent a biological control.

The CSIRO predicts the job will take at least 10 years.

By that time, the toad is expected to have spread throughout Kakadu's internationally
renowned wetlands, invaded Darwin and be hopping west towards the Kimberley and Pilbara
regions of Western Australia.

Some experts predict the toads will also extend the invasion of temperate Australia
to establish themselves in pockets along the length of the Murray River.

When the CSIRO's preliminary work comes up for review in November next year, the nation
will have had time to come to terms with the fact that toads were poisoning Kakadu's world
famous biodiversity.

And there is no guarantee that the research money won't be turned off again as it was
four years ago.

The CSIRO's aim of sabotaging the toad's DNA to prevent it metamorphosing from a tadpole
builds on research that ended abruptly in 1997.

It seems the historic neglect of the problem of the toad in Australia may explain why
research has not attracted the government support that many scientists argue is warranted.

When the funding rug was pulled after five years of research in 1997, CSIRO pest expert
Dr Lyn Hinds said a reason cited was that evidence of the toads' destructive impact was
largely anecdotal.

"One of the reasons that did come out was that cane toads have never been identified
as a threatening process in the environment," Dr Hinds said.

"Their impact on the environment has not been clearly defined - nobody has been able
to categorically say that cane toads are making other species extinct as could be said
about the impacts of rabbits, foxes and feral pigs."

Northern Territory Parks and Wildlife Commission director Bill Freeland is among those
who do not see the toad as a catastrophe for Kakadu.

"As yet, nothing has gone extinct in Queensland or in the Northern Territory," he said.

"And that suggests to me it's not a huge, huge problem."

While Kakadu's managers concede they are powerless to stop the toad, they are making
unprecedented efforts to quantify its impact, particularly on the vulnerable quoll and
goanna populations.

Goannas have been fitted with radio transmitters to gauge how they will alter their
habitats because of the toads.

Electronic listening posts have also been installed in strategic locations throughout
the park which will pick up the toads' calls and indicate the prevalence of native frogs
in the same habitats.

Tropical wildlife expert Professor Peter Whitehead predicted species such as the goanna
would be hit hard but would eventually bounce back.

Prof Whitehead, director of the NT University's key centre for tropical wildlife management,
expected that native animals would eventually learn to avoid the toxic toad.

"The risk is that people will see fewer of these animals for some years, perhaps decades,
rather than species being entirely wiped out," he said.

Environment Australia's national parks director Peter Cochrane agrees that wild life
would return to Kakadu in time.

And he expected some positive affects from the toad invasion in reductions in feral
pigs and cats.

But Adelaide University toad expert Associate Professor Mike Tiler predicts the toad
will take over Kakadu with disastrous results.

"The cane toad when it gets to Kakadu is going to become the most abundant form of
life," he said.

"There's no doubt whatsoever that there is going to be more cane toads in Kakadu National
Park than any native species."

Former federal environment minister Robert Hill, who funded the latest quest for a
biological control, dismisses suspicions that the problem would be better funded if the
toads were having an economic impact on agriculture.

"If it's doing damage to the natural environment or irreplaceable assets, then it is
just as important as any commercial loss," Senator Hill said.

"But the problem is that pouring money at it doesn't necessarily find your solution."

AAP rmg/gmw/br

KEYWORD: TOADS YEARENDER

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