Still, this year’s plague could be Australia’s worst in 20 years. Despite control measures, the adult locusts have already laid their eggs. If the winter and spring rains are good–and they are expected to be–the outbreak after the eggs hatch could dwarf the current infestation. The locusts could spread through the whole state of South Australia, threatening hundreds of millions of dollars’ worth of damage to pasture lands, wheat crops and even the grapes of the Barossa Valley, which produce Australia’s finest wines.
The challenge is to wipe out the bugs without killing everything else, too. The Australian Plague Locust Commission has been aerial spraying fenitrothion, a high-powered pesticide. Scientists say the chemical is safe: it has a half-life of a few days, and cattle can graze in treated paddocks after a week or two. But aerial spraying can’t be used in built-up areas or on the increasing number of farms that specialize in organically grown vegetables. As an alternative, the commission is testing out a biological agent, metarhizium, a fungus that kills the locusts. But the fungus takes 10 days to work; in that time, the locusts can easily destroy entire farms. The insects “leave a denuded band across the ground in a crescent shape,” says Hillston rancher Rob Collins, whose pastures haven’t been hit yet. Each band can stretch for kilometers.
Things may only get more dire in October. That’s when the locusts’ eggs will hatch. (The spray doesn’t kill the eggs.) The moisture in the ground has made conditions ideal for locust breeding. According to the commission’s chief entomologist, David Hunter, spraying and releasing the fungus has significantly cut the locust population. But, he says, if all the eggs hatch, the number of locusts could grow by seven or 10 times. “There are still lots out there,” says Hunter. “When the offspring come out, they’ll be back to high-density swarms.” Local farmers, who have struggled through years of drought and low commodity prices, are philosophical. “Any reduction in yield is a loss,” says rancher Collins. “Ah well, if [farming] was easy, monkeys would be doing it.” And there’s always another drought to look forward to.
