Another plague has descended on the West. This one chirps.

Millions of Mormon crickets are returning to the open range across the region, which is already struggling with a severe drought and bracing for the wildfires that summer brings.

The pests travel in huge packs and eat everything in sight. They are chewing up farming fields and ranching pastures, besieging backyard gardens, even blanketing some stretches of rural highway. The infestation has spread across several million acres in Nevada, Utah and Wyoming.

The voracious crickets, which grow to three inches in length and resemble grasshoppers, are no strangers in the West. They got their name after wiping out crops of Mormon settlers in 1848.

Whenever the region has recurring mild winters and dry springs, they hatch in droves. And hardly anything slows them down. Some swarms cover 40 acres.

Western officials say they have been fighting a losing battle against the crickets for the past few years -- and expect the invasion to double in size this summer.

Across northern Nevada, more than 12 million acres are infested. Some highways are slick and dangerous because so many crickets are crossing the road and getting squashed. The bugs also are covering the rooftops and exterior walls of some homes.

By land and air, with pesticides and poisonous bait, an aggressive and expensive counterattack is underway. But what the West needs most to stop the crickets is a long, cold winter.

"The ground is just black with them in some areas. They can climb up houses, cars and trees,'' said John O'Brien of the Nevada Department of Agriculture. "It can be pretty unnerving for people when they first see it."

-- Rene Sanchez