CANE TOADS - Rethinking Invasion Ecologies from the Environmental Humanities - page 151

Filming cane toads: from 'unnatural history' to 'conquest'
It is important to look at the techniques of representation in Mark Lewis's films as
they are central to the way in which he politically and ethically reframes the
invasion of cane toads, allowing new ecologies and nature-culture relations to
emerge from the more conventional narrative of ecological disaster. Cane Toads:
An Unnatural History (1987) is a 47-minute documentary, originally produced
for television but later given a cinematic release. 3 It tells the story of how the cane
toad, a species native to Central and South America, was introduced to Australia
in 1935 in an effort to eradicate the scourge of cane grubs from Queensland's
cane fields. The grubs of native French's cane beetles and greyback cane beetles
(known commonly as witchetty grubs or cane grubs) were burrowing into the soil
and attacking the roots of sugar cane, reducing crop yields by as much as 90 per
cent. Under pressure to find a solution, scientists working at the Queensland
Government's Bureau of Sugar Experiment Stations (BSES) seized upon a scientific
study by entomologist Raquel Dexter, which appeared to link the introduction of
cane toads to Puerto Rico with a corresponding drop in the population of white
grubs that were decimating the nation's cane fields. However, the science behind
Dexter's study was completely flawed (Turvey, 2010: 6-7)—a point that is left
unexplored in the narrative of Lewis's film. 4 Nevertheless, through a visual montage
that reconstructs the toad's journey and a series of interviews with scientists,
government officials and farmers, the film explains how a batch of 102 cane toads
was imported to Australia from Hawaii (another outpost of the sugar trade), before
being bred and released at various sites around Gordonvale in north Queensland.
In spite of warnings from at least one prominent entomologist that the toad
might become 'as great a pest as the rabbit or the cactus', a reference to the advance
of prickly pear, the prevailing belief among BSES entomologists was that the toad
would eat only cane beetles and other night-flying insects. 5 The film portrays the
reasons behind the toad's importation as a mixture of commercial and government
pressures that coalesced into the prospect of a successful biological solution, which
was championed by many leading scientists. The reality, overlooked at the time by
the assembled experts at the BSES, was that the toads and beetles rarely came into
contact with one another. As Dr Glen Ingram, an expert on amphibians inter-
viewed in the film reveals, 'The lifestyles of the cane beetles and the cane toads just
didn't synchronise.' The beetles lived in the cane stalks and the toads lived on the
ground, meaning that adult beetles were only vulnerable to the toads for the brief,
hour-long interval in which they emerged from the soil, before flying off to forage
in the trees.
Cane beetles were eventually controlled by the pesticide benzene hexachloride
in 1945, which was marketed to cane farmers as Gammexane, until it was found
to be carcinogenic and withdrawn from sale in 1987. But the toad proved to be
remarkably adaptable to its new environment and quickly multiplied and spread.
Its omnivorous eating habits and its possession of a highly poisonous bufotoxin,
secreted from glands on either side of its head when it is attacked by predators,