“Climate change is of concern to all of us, and when we see extreme events such as a very severe drought, we see an increase in natural phenomena such as grasshopper outbreaks,” Sharon Selvaggio, former biologist of the United Nations, told CNN. US Fish and Wildlife Service. “This is very worrying.”
Federal agriculture officials say they saw the outbreak come after a 2020 investigation that found a high concentration of adult grasshoppers in the West.
To mitigate other drought-fueled economic impacts, the agency launched a grasshopper destruction campaign – the largest since the last outbreak in Montana in the 1980s.
Agriculture officials plan to aerial spray more than 2.6 million acres of Montana prairie with insecticides in an attempt to kill grasshopper populations. It is an area larger than the state of Delaware and Rhode Island combined.
This is not the right approach, said Selvaggio, now a pesticide program specialist for the Xerces Society, a nonprofit conservation group that protects habitats from insects, adding that it will be ineffective in the long run.
“The problem with insecticide treatments is that they could actually worsen grasshopper outbreaks in the future by harming natural enemies or locust competitors which under natural conditions serve to control pest locusts,” said Selvaggio.
The USDA says it will only spray in low concentrations to kill grasshopper nymphs, as adult grasshoppers need larger amounts of insecticides.
And while grasshoppers tend to emerge during particularly hot and dry years, environmentalists say their massive appearance depends on many aggravating factors, including climate change.
“We have to think of it as a system, not just a symptom of the problem,” she said. “Grasshoppers are a symptom of an unbalanced ecosystem. We need to look at the role of vegetation cover and diversity.”
Selvaggio likens the disturbance of grasshoppers to fire, pointing out that aggressive fire suppression practices in the West have never succeeded in eliminating the risk in the long term. Spraying insecticides to rid rangelands of grasshoppers, she says, will have the same result.
“We need to take a management approach that emulates the natural disturbance regime seen as a better way to make forests and fires resilient,” said Selvaggio. “We need a similar approach for managing grasshoppers on the rangelands.”
This year’s drought and heat waves have broken all records – a clear signal that climate change is already impacting all aspects of life. And because of these extreme climate changes, Selvaggio says how land and ecosystems are managed matters.
“Climate change could bring us more locusts in the future with increased frequency, duration or severity,” she said. “We need these long-term solutions to tackle grasshoppers in the long term, because we know we could face more problems in the future if we don’t take this really seriously.