Drought puts Alberta farmers at risk of another scourge of grasshoppers

The two-striped grasshopper is one of the pest species that commonly damages crops in Alberta. (Dan Johnson/University of Lethbridge - image credit)
The two-striped grasshopper is one of the pest species that commonly damages crops in Alberta. (Dan Johnson/University of Lethbridge - image credit)

Will Muller knew immediately that he had a grasshopper problem last spring.

Dealing with drought conditions at his farm near the town of Bow Island in southern Alberta last year, he could see the insects hopping all over the fields where he grows lentils, durum wheat, canola and beans.

"If you went into the field, you drove in there and the grasshoppers would be flying everywhere, which I'd never seen," Muller said.

"You could see the chewing on the plants right away as well and the leaves being chewed on."

Grasshoppers thrive in hot, dry conditions that are already putting many farmers and ranchers on edge across Alberta. With parts of the province at heightened risk of another bad outbreak in 2024, it's a waiting game to see how many insects take wing, potentially putting even more pressure on farm operations.

As of the end of March, Alberta's worst drought hotspots are in east-central and southeast Alberta, as well as a growing area of the Peace River region in the northwest.

Some grasshopper species are major agricultural pests, emerging in the spring from eggs laid the previous summer, and gobbling up crops. And after major grasshopper outbreaks in parts of Alberta last year, there are plenty of eggs now lying in wait.

Meghan Vankosky, a field crop entomology research scientist with Agriculture and Agri-Food Canada, said she saw some of the problems first-hand when surveying in west-central Saskatchewan, where grasshoppers were also an issue last year.

"They get caught in the wind and blow back into your face, and it hurts to get smacked in the face by a grasshopper flying through the air, especially when they're big," she said.

When grasshopper outbreaks are bad enough, they can decimate crop yields.

"It's just terrible for farmers, because there's nothing they can really do after a certain point," Vankosky said.

"Toward the end of the summer, as far as you would look into a wheat field, you couldn't see any plants with leaves. It was just like the central stalk and this poor little wheat head trying to develop with no foliage at all."

Grasshopper counts are conducted every summer across the Prairies, and the results help set a risk rating for the following year.

This year's provincial forecast notes that one problem species in northern Alberta, the Bruner's spur-throated grasshopper, has a two-year life cycle. After outbreaks last year, that means they aren't expected to pop up in large numbers in 2024 — but there could still be other pest species present.

In southern Alberta, the forecast warns that grasshoppers have had two straight years of "ideal conditions" for egg laying and development, and that means, "If you had grasshopper issues in 2023, expect the same for 2024."

Crucial time for grasshoppers coming up

Dan Johnson, a University of Lethbridge environmental science professor, said the most critical period for grasshopper development is still ahead.

Dan Johnson/University of Lethbridge
Dan Johnson/University of Lethbridge

"What matters the most is what happens in May," he said.

Alberta didn't see grasshopper problems across the board last year, but for areas where outbreaks could repeat, the question now is how hot it might get next month, and the timing of any rainfall.

"When [grasshoppers] first hatch, they come out, they're so tiny … and they're very sensitive to rain and mud and things like that," Johnson said.

"If it's nice and hot and warm, they can go through a stage and shed their skin and go to the next stage in like four days. But otherwise, they'll just sit there for weeks, and their life is just dribbling away and they're not really growing.

"But the dry heat, that's perfect for them. They just rocket through."

Johnson said the way grasshoppers have been emerging lately is predictable, especially after compounding years of drought in southern Alberta.

But the way patterns of different pest species are shifting poses a challenge for agricultural producers, and for governments trying to mitigate their impact on the food supply.

The province recommends farmers start scouting for grasshoppers early, especially if they're in areas where the risk rating is higher. That's because it's easier to try to decrease their numbers with pesticides if they're caught earlier in their life cycle.

Muller said for now, concerns about grasshoppers are secondary to the danger that drought poses for his crops. But after the pests caught him off guard last year, he's trying to get ready by spraying his dryland fields in the hopes that would help reduce the number of grasshoppers laying eggs there.

"All of a sudden we've got to spray for bugs that we aren't used to — it's more money," Muller said.

"And you've got droughts, you've got less crops. So it's not an awesome situation, but hopefully we don't see it this year — hopefully we get some rains."