The big picture: Bats are under threat globally due to habitat loss. Giving them a safe place to roost helps protect these nocturnal MVPs — key pollinators that also spread seeds and devour pesky insects like mosquitoes, wasps and flies.

• D.C. is home to seven bat species — including two that are threatened or endangered.

Fun fact: The big brown bat is D.C.'s "state" mammal — and the one you're most likely to spot.

Friction point: If you build it, they might come. "Bat houses are complicated to get right," warn experts at Bat Conservation International. "They can go unused for years, attract pests, and even harm bats when installed incorrectly."

Yes, but: The effort can pay off, especially in cities. Without a proper roost, bats may end up in less-than-ideal spots like attics or lofts.

Zoom in: The Back Yard Bird Feeder, a longstanding local company with 5 DMV locations, sells Songbird Essentials bat houses for around $90.

• They're built to last — with sealed roofs, ventilation and space for up to 100 bats — and boast a "proven 80% occupancy rate," sales specialist Vianca Trinidad tells Axios.

🦇 What to know:

• Height matters: Aim for at least 15 feet off the ground — "the higher, the better," Trinidad says.

• Skip the trees: Mount on poles or buildings to avoid predators like raccoons and owls.
• Sun is your friend: Bats prefer warm roosts, so direct sunlight helps.
• Bring patience: It can take a year or more for bats to move in.

The intrigue: You won't see inside the box — but you'll know it's working when guano starts piling up below. Great for fertilizer — bad if it's over your grill, so plan carefully.