Mormon crickets moving through Oneida County and other areas are causing some damage to pastures, according to officials with the U.S. Department of Agriculture (USDA). 

USDA officials said they’re aware of Mormon crickets near the Elkhorn Mountains, Malad Range (Highway 36), Pleasantview Hills and Samaria Mountain. 

“Oneida County is where highest population counts have been observed,” according to information provided by USDA officials. “We have found counts of up to 15 crickets per square yard.” 

Mormon crickets are related to grasshoppers; they don’t fly, but they can migrate great distances and they travel in wide bands, according to a USDA Animal and Plant Health Inspection Service fact sheet. 

“Both (grasshoppers and Mormon crickets) damage grasses and other vegetation by consuming plant stems and leaves,” according to the fact sheet, which adds that they can harm plants’ growth and seed production and reduce livestock forage.

Some landowners have reported such damage to their pastures recently, USDA officials said.  

“In general, cricket outbreaks can cause significant damage to rangeland and crops. They have also been known to cause road slicks and to foul livestock water tanks,” according to the information provided by USDA officials. “Crickets are also a nuisance for a variety of outdoor activities.”

Some Mormon crickets can be found any year given that Southern Idaho is their home range, but populations have been unusually low in Idaho over the past two years, according to USDA officials. They said there isn’t a lot of information available as to what causes outbreaks like the one occurring in eastern Idaho, but they do happen on occasion. 

“The last outbreak in this vicinity was 2006. Before that, there were major outbreaks in 1993 to 1994,” according to the information provided by USDA officials.

USDA and Idaho State Department of Agriculture (ISDA) officials are working together to monitor and suppress the Mormon crickets. USDA officials said they treated 85 acres of U.S. Forest Service land with carbaryl bait, an insecticide, in mid-June, and ISDA has given additional bait to county Extension offices to assist ranchers and farmers.

While USDA officials are working to suppress the crickets currently traveling through the area, they’re concerned that the outbreak could cause similar problems next year.

They said crickets in western Idaho have laid eggs, and they believe the insects in eastern Idaho will do the same thing. 

“Once eggs have been deposited, the majority of crickets will begin to die off.  While the immediate problem is resolved, there is a higher risk of an even bigger problem next year,” according to the information provided by USDA officials.

“Farmers and ranchers should observe these hatching sites and take action early next spring if needed.”