Big brown bats (Eptesicus fuscus)
Big brown bats are frequent building roosters across Spokane, Spokane Valley, and the Tri-Cities. They are hardy, tolerant of cooler attics, and often use older homes with loose fascia or uncapped chimneys. Their larger size still fits through surprisingly small gaps. Colonies can persist year after year if secondary openings stay open.
Little brown bats and Yuma myotis
Little brown bats (Myotis lucifugus) and Yuma myotis historically formed large maternity colonies in warm attics and barns across the inland Northwest. White-nose syndrome has stressed some Myotis populations, which makes humane exclusion—and never poisoning—even more important. When these bats use a structure, expect tighter entry points and careful maternity timing.
Other species you may see outdoors
Hoary bats, silver-haired bats, and Townsend’s big-eared bats occur in Washington habitats but are less commonly the “colony in my attic” problem. Evening flyovers along the Spokane River, Yakima Valley orchards, and Columbia River corridors are often solitary or tree-roosting species doing their job on mosquitoes and agricultural pests.
Why species ID changes the job plan
Species clues (size of guano piles, roost height, chimney vs. ridge use) guide device choice and sealing materials. We do not need a lab ID to start helping you—but we do need accurate mapping of every opening before one-way exclusion. Protected status under state wildlife rules means exclusion, not extermination.
Ready for help in Spokane, the Tri-Cities, or elsewhere in the 509? Start with bat removal or an attic inspection.