Cane toads in Australia
Cane toads are large toxic frogs native to Central and South America.
They were introduced into Australia in 1935 in an attempt to control pest beetles of the Queensland sugar cane industry.
They have rapidly spread across Northern Australia and are still marching Westwards at a rate of 50km per year.
They are also spreading South from their point of release but at a much slower rate.
Biology
True toads, native to South America
Produce 'Bufotoxin', a powerful poison that causes a heart attack.
Poison is stored in shoulder glands and is released if the toad is attacked
Females can lay up to 30,000 eggs per clutch (twice a year)
Impact
Impacts are minor on many native animals (frogs, fish, birds, small mammals)
Bufotoxin is highly poisonous to most large Australian predators
Declines in predators disrupt ecosystem function and indirectly impact other species
Invasion
Invasion moving at 50km/year across N. Australia
Invasion front consists of very large, toxic toads - all deadly to predators
Smaller, less toxic toads not present in the environment for a year post-invasion
Control
Australia will never eradicate cane toads
Killing single toads has little overall conservation effect due to high reproductive rates
Local control may be possible with combined methods
Myths
Contrary to widespread beliefs:
IMPACT: Cane toad invasion has a direct impact on only a small number of native species (the predators), but has indirect impacts on many more (some impacts are positive!)
DANGER TO HUMANS: Drinking water is NOT poisoned if toads breed or swim in it because the toxin is stored in the body/eggs
Resources
Cane toad research activity:
Research papers: