“We have an increased sense of urgency in terms of wanting to make sure that we’re controlling the mosquito population to the very best of our ability,” Ms. Bosworth said, alluding to the viruses. “Just having bat houses isn’t going to be the answer, but at least it’s looking toward a solution that is environmentally friendly.”

Over the years, the Boy Scouts and Girl Scouts have chipped in and built some of the houses. This year, Yianni Biniaris, 16, from Manhasset, N.Y., hopes building, repairing and replacing bat houses at the Clark Botanic Garden here will help him attain the rank of Eagle Scout. His project has been approved by North Hempstead, but it still needs to be cleared by the Scouts.

“Using the bat houses is more of a friendlier way of getting rid of mosquitoes, while saving the bat population,” Yianni said last month at the garden, home to about 20 of the houses.

His mother, Stella Biniaris, said wanting to remove bats from behind the shutters of their house had led her son to the project.