Toad Media
MEDIA TimesOnLine
October 06 2006
London Times - Volunteer army tries to halt toxic toad invasion
From Bernard Lagan in Sydney
http://www.timesonline.co.uk/article/0,,3-2391312.html
THEIR
poison kills with gruesome efficiency and, after 70 years on the
march, they are a season away from conquering Australia from east
to west — almost wiping out once plentiful native animals.
The importation in 1935 of 3,000 cane toads from Hawaii to control
beetles in the eastern sugar plantations has unleashed one of Australia’s
greatest ecological disasters.
After a 1,800-mile (2,885km) journey across the Outback, the toads,
which can weigh more than one kilogram (2¼lb) and grow up
to 23cm (9in) long, have settled in their millions in the World
Heritagelisted Kakadu National Park.
For the next month, scores of volunteers will attempt to thwart
the westward march, killing as many as possible. There they have
decimated native populations of goannas, the native Australian monitor
lizard that grows up to 160cm (5ft) long, and northern quolls, a
native rat-like creature that grows to the size of a cat.
Such has been their effect that quolls are being transported to
outer islands to try to preserve their numbers.
The toads secrete a lethal venom, which paralyses and kills any
animal or reptile, including crocodiles and dingos, that tries to
eat them.
They have no predators in Australia and female toads spawn twice
a year, producing up to 35,000 eggs a time. Studies conducted at
Sydney University show that the toads are evolving longer front
legs to speed their conquest of the Outback.
“Their impact is catastrophic,” said Tony Griffiths,
a research Fellow at Charles Darwin University in Darwin. “What
is going to be interesting in five years’ time is whether
those populations [of now endangered native species] will still
be able to persist at very low levels.”
Naturalists predict another unexpected result of the cane toad
explosion: a rapid growth in the crocodile population of northern
Australia. Goanna numbers along rivers southeast of Darwin are now
so low that one of their favourite foods — crocodile eggs
— are being left untouched. Up to 95 per cent of crocodile
eggs are usually eaten by goannas. Last month scientists found that
this had dropped to about 20 per cent.
Other studies show that endangered turtle species are also benefiting
from the survival of eggs that traditionally would have been eaten
by goannas.
The state of Western Australia is the only area to have been spared
the toads so far. However, they have been sighted less than 100
km (60 miles) from its eastern border.
Dennis Beros, one of the cull organisers, said: “The plan
is to drive the toads back each year until a biological king-hit
can be found to put the toad genie back in its bottle.”
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