PICTURED HERE ARE BAT EXLUSION EXPERTS, ALEX SVENSEN AND JASON NEITENBACH WORKING ON A "BAT PROFFING" JOB IN PAINESVILLE, OHIO - They understand bat-handling, bat control techniques, bat biology and bat habitats. Exclusion is the best way for eliminating and preventing bats from residing in structures. The challenge is to avoid trapping young pups, and to prevent bats from relocating in the structure through other openings. Repairs or modifications to the attic, soffit, and roof may be necessary. Although tedious, it is necessary to locate all active and potential openings available to bats. This may require a lot of ladder work, and a machine lift may be necessary. Active holes can be identified by rub marks, guano, and sometimes odor. Look for gaps or openings around chimneys, fireplaces, plumbing, piping, attic doors or hatches, windowsills, air conditioners, ducts, louver fans, and pet doors. Broken window and door screens, and even open windows, can provide entry points. Because bats use some of the same holes in buildings where heated or cooled air is lost, bat-proofing often reduces energy costs for the client. Except for the actively used holes, seal all gaps of ¼ x 1½ inches and openings 5/8 x 7/8 inch or greater. However, be aware that sealing gaps can have disastrous effects on bat pups if done at the wrong time.