More than 1,000 miles of irrigation canals and ditches thread through the Treasure Valley in Idaho, transforming what was once an arid and remote high desert into one of the most fertile and fastest-growing parts of the country.

They’re also a rat superhighway.

The suburbs around Boise are suffering from a rat explosion. Pest control operators in the state have reported record calls. Health officials have floated declaring a public emergency, and elected leaders are arguing over who should be responsible for a problem that stretches beyond any political border.

Most fingers are pointing west, toward California.

“Check your luggage before you move,” Brad Pike, the mayor of Eagle, Idaho, said during a recent City Council discussion.

He wasn’t entirely kidding.

The rodent problem became a public concern thanks largely to one person, the retired naturalist and Eagle resident Jane Rohling. Around 2022, she started noticing rats in her backyard, a suburban idyll with raspberry bushes, cherry and apple trees and several bird feeders — a veritable rat buffet.

“I looked out one day, and there were four rats right at the base of that feeder — in the daytime,” she said. “That meant I already had a problem.”