Farmers in western US battle locust swarms

By Elizabeth Schroeder | 28 July 2024 | 7:43 pm

There have been reports of widespread locust and Mormon cricket infestations in at least seven states in the western US.

The Mormon cricket (Anabrus simplex) is a large insect native to western North America.

A recent report in the Los Angeles Times ascribed the outbreaks to the current drought conditions driving these insects, which thrive in dry grass, into areas that had previously been untouched by them.

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The report stated that hundreds of farmers and ranchers across the region had lost their crops last year, with millions of dollars in damage suffered.

Rob Wilson, a co-operative extension livestock and natural resource adviser at the University of California, said the state’s current drought “and the curtailment of irrigation water available to agriculture has had the greatest impact on crop-damaging pests”.

He said that because the land area being irrigated was being reduced, it also curtailed crop rotation opportunities. In addition, greater weed infestation on non-irrigated land had had a significant impact on pest migration.

“We have observed this with locusts and thrips,” he said.

An increase in pest infestations had also been observed in Colorado this summer, Wilson added.

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“The impact of climate change on drought cycles and severe weather and its resultant impact of crop growth and pests is threatening,” he said.

When asked whether the increase in locusts was the result of climate change, he said that he had observed changes in the emergence of weeds and insects in crops.

“For example, we have weeds germinating later in the autumn and earlier in the spring due to warmer soil temperatures,” Wilson said.

In an interview with the Agriculture Dive website, Dr Emmanuel Attoh, a researcher and climate adaptation specialist at the International Water Management Institute, said: “Climate change is significantly impacting crops and crop pests, creating challenges for farmers across the globe.”

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Wilson added that for farmers around the world, overcoming changing weather patterns and fluctuating pest life cycles would be a challenge.

“Farmers have limited opportunity to mitigate these threats as they can’t easily move their operations to new lands; they do not have control of when and how much surface irrigation water they receive; they lack native crops that are profitable; their costs are increasing at rapid rate, preventing investment in research and new technologies; and they do not have control of land management on surrounding lands,” he said.

Agriculturedive.com reported that swarms of these pests were also impacting beef and dairy production. The insects were laying eggs in autumn that were hatching by the following summer; these hatchlings then fed on hay and grass such as alfalfa, which was commonly grown for cattle feed.

As the locusts proliferated, they destroyed these feed stores, forcing ranchers and dairy farmers to reduce their herds, the report added.

The state of Oregon had reportedly earmarked US$1,2 million (about R22 million) for locust mitigation during the previous legislative session.