Locusts threaten to devour crops in Alberta after extreme heat

Driven by drought, heat-loving locusts are thriving in Alberta, threatening to devour crops in central and southern parts of the province.

Pest locusts are flying out early this year — and swarming in greater numbers.

Robert Badry, who runs his family’s grain farm near Heisler, 100 miles southeast of Edmonton, said half an acre of his wheat crop was devoured within days.

“The ground literally moved with them,” he said. “It was bare, you could see the ground. They just ate it to nothing.”

Locusts have long been a threat to agricultural producers. Like locusts, the insects are incredibly destructive. Even a moderate infestation – 10 locusts per square meter – can eat up to 60 percent of the available vegetation.

This year, the hot and dry weather that fueled Alberta’s historic wildfires has contributed to a plague of locusts that is already threatening to destroy stunted crops.

Experts warn that the infestations increase the risk of future outbreaks and recall the need for better monitoring of the infestations.

Recent rains may have slowed down the locusts, but only temporarily, as the population has been booming for years.

On his farm, Badry worries about the prospect of continued outbreaks.

He expects the locusts to move back in when the dry weather returns. His crops already suffer from a lack of moisture, making them susceptible to poor yields and pests.

“Once the drought hits and you see the locusts, don’t be surprised, they go hand in hand,” he said. “They thrive in the drought and the dry.

“If it’s not one thing, it’s something else this year.”

The Alberta government monitors locust outbreaks and tracks populations through a annual census conducted every August.

Last year’s research warned of the continued risk of outbreaks in southern Alberta and along the Saskatchewan border. Contaminations were found in isolated pockets in the Peace River region. In the south and east, numbers have been increasing since 2021, the survey found.

A plague of vermin

Meghan Vankosky, a research scientist at Agriculture and Agri-Food Canada and co-chair of the Prairie Pest Monitoring Network, said 2023 is the worst year for locusts she’s seen in more than two decades.

After this year’s wildfires and record rainfall in Alberta, it’s an anxious time for producers, Vankosky said.

“We’re talking about the four horsemen of the apocalypse, aren’t we?” she joked.

Vankosky urges farmers to keep a close eye on their crops. As other food sources, such as wild grasses, flowers and foliage plants dry out, locusts will move to crops for a meal.

“It’s not just that we have a lot of locusts this year, it’s also that the crops aren’t necessarily growing very well and so the damage is much more noticeable,” Vankosky said.

“They tend to prefer grains, oats, wheat, rye, barley… But in a dry year, they’re really going to eat whatever they can find.”

Although the life cycle varies by species, locusts invariably thrive in heat.

Females lay eggs in the soil in late summer. After a winter just below the surface, nymphs emerge from their seed pods in spring. They feed on vegetation as they mature, molt and grow wings.

Warm weather increases survivability and speeds up each stage. The insect’s body temperature shoots up, allowing it to grow faster and females to produce more eggs, leading to ever-larger hatches each spring.

Vankosky said the warmer temperatures this year have allowed the insects to fly early and fly to new food sources.

“When it’s warm, they develop faster than normal, and that’s really what we’ve seen this year.”

Alberta is no stranger to outbreaks. In 2021, locusts swarmed Lethbridge, devastating fields and backyards.

Before it became extinct in the late 1800s, a locust known as the Rocky Mountain locust swarmed the west. Blizzards of insects would obscure the sun.

Locust expert Dan Johnson, a professor of environmental science at the University of Lethbridge, recalls outbreaks in the 1980s when cars and trucks were pushed off the road by clouds of locusts hovering over highways.

Johnson describes this year’s infections in Alberta as “patchy,” with isolated hot spots where populations are dense.

“Where they are, they are very heavy,” he said. “And it’s a double whammy because they come when the drought is already causing problems.”

Friend or enemy

Johnson said pest populations have been increasing since 2018. Recent infestations should serve as a reminder that not all locusts pose a threat to producers, he said, adding that the pests can be selectively controlled with pesticides.

Some species are harmless to crops and play an important role in grassland ecosystems, where they serve as meals for birds and other prey.

“There are about 50 fairly common species and only about five of those are the bad guys,” Johnson said.

Pest species include the clear-winged locust, Packard’s locust, the migratory locust, and the two-striped locust, which is considered the greatest threat.

The Bruner’s locust is a relatively new rogue on the list of species found in Alberta, Johnson said.

Populations of Bruner’s locusts have exploded in recent years with numbers reported from Edmonton to the Peace River region. Johnson expects their range and number to continue to grow.

Governments and manufacturers need to be better prepared for possible invasions, Johnson said.

The current increase in numbers has been made possible by successive years of drought: warm, dry springs and hot early summers. If the trend continues, serious infestations will continue to escalate, he said.

Locusts and locusts are a global threat to food security and an international effort is needed to reduce problem species, he said. Predicting population explosions – and the extent of damage that will be caused – can be incredibly difficult, but the risks must be managed.

“We can never really wipe them out,” he said. “But if we can make sure they don’t get completely out of hand, that’s the way to do it.”