Cooperative Extension Service In-service training - 2013

1. Nuisance Bat Control Cooperative Extension Service In-service training - 2013 Blake Sasse

2. General information • 16 species of bats in Arkansas • The only flying mammals • Can live for a long time—Little brown bats have been known to live as long as 34 years • All Arkansas bats are insect eaters

3. Safety Issues • Falls (from roof or ladder) • Electrocution • working near power lines, live wires in attic • Tool accidents • hammers, nailguns, etc.. • Heat • working in hot attics, rooftops • Histoplasmosis (from bat/bird droppings) • Animal bites (bats, rodents in home) • physical injury (usually minor) • rabies

4. Histoplasmosis Safety Measures • Minimize disturbance of guano to prevent spores from becoming airborne and inhaled • Don’t shovel out or sweep up dry, dusty guano • Wet the guano down with a water spray before removal to lessen the amount of dust. A surfactant (wetting agent) may help • Industrial vacuum cleaner with high efficiency filter • Full face-piece respirator • There is no EPA approved disinfectant that “kills” histoplasmosis spores

5. Rabies Safety Measures • Avoid handling bats • Wear leather gloves when doing so • Rabid bats may act calm or agitated, so must always be careful in handling them • Should receive pre-exposure vaccination treatment if dealing with bats regularly

6. Nuisance Bat Complaints Received by AGFC Nongame Mammal Biologist, 2000-2011

7. Single bats in a living area • Bats usually come in through an open window or door • Wear leather gloves • Wait till the bat is hanging on wall and capture it between a bowl and piece of cardboard • Release outside on tree • Or close interior doors, open windows, turn on lights and wait for it to fly out

8. Colony Exclusion • This is really a carpentry problem, not a bat problem • The long-term solution is to get the bats out and close the entry points they used to get in the house

9. First, find where the bats are getting in the building • Watch building beginning about a half hour before dark • See exactly where bats are exiting • Look for staining on walls underneath potential exit points

10. Common exit points Bat Conservation International

11. Staining underneath exit point Pieces of guano Photo: David Saugey

12. Photo: David Saugey

13. One-way door on a roof vent Duct tape, staple or tack on sides and top Plastic sheeting 18-24” Bottom left open with about 1” of free space between plastic and house

14. Photo: David Saugey

15. Photo: Laura Finn Exclusion tubes

16. Photo: Laura Finn 2-3” diameter caulk tubes. May be more effective if add 6” of heavy plastic in tube shape on the ends of the caulk tubes

17. batcone.com

18. Photo: Joel Dunaway Bat House Original Exit Exclusion Tube Tube laid close to hole with mesh connector

19. How long do you leave devices in place? • Spring – Fall • After a week or so, if no more bats are exiting the door, take it down and fix hole • Watch the house before nightfall again to make sure they haven’t started using another hole • If they do, repeat whole processagain • Winter • Bats will probably not fly very often • Door may need to be left up for a few months unless you can confirm the bats have left the site sooner • Easy to do in an attic, hard to check inside walls

20. Keeping the Colony Out • Once the bats are out, fix the hole • Screening • Be sure to place on outside of vents • caulk • steel wool • replace rotted/broken boards

21. Bats Hanging On the Outside of Screens in Attic Louver vents • When bats can’t get into an attic they sometimes hang on the outside of the screens on attic louver vents underneath the wooden slats • Wait until night and if all bats have left, put up screening on outside of the louver vent • If no babies are present and you have access to the attic, you can sometimes “encourage” them to leave by squirting them with spray bottle full of water from inside the attic, then when they’re gone, put screening up on the outside

22. Single Bats Hanging on a Porch or Carport • No permanent solution • Wait till the bat has flown at night and spray the site they were using with commercial aerosol dog or cat repellent • This will sometimes keep them from returning to that site for a month or more • Cover area where they like to hang with plastic so that they can’t get a grip on it

23. Protecting baby bats • Most Arkansas house bats have their young in May and June • In order to avoid trapping the pups inside the house, no exclusions should be performed from May-July 15 • Avoids unnecessary harm to bats • Eliminates decomposition smells

24. Other options • Bat repellents: • Napthalene (mothballs) has had some very limited success, but has to be replaced often. Apply at 2.5 lbs./1000 cubic feet. Prolonged inhalation may hurt humans. Not recommended as it has health risks. • Lights: Sometimes placing strong lights in the roost area will drive bats out • May cause electrical hazard (frayed cords) • Ultrasonic devices or bat call tapes: Totally ineffective

25. Bat Houses • Bat houses alone will not draw a bat colony from a house. They should be put up before performing a standard exclusion • Preferred location would be near previous entry points on structure, or on pole in yard • Need strong sunlight, 12-15’ from bottom of house to ground • 97% of bat houses put up in conjunction with exclusion were occupied in 1999

26. Web sites Arkansas Game and Fish Commission Nuisance Wildlife Control site http://www.agfc.com/species/Pages/SpeciesNuisanceWildlife.aspx Bat Conservation International • http://www.batcon.org Internet Center for Wildlife Damage Management • http://wildlifedamage.unl.edu • Centers for Disease Control • “Histoplasmosis - Protecting Workers at Risk” • http://www.cdc.gov/niosh/docs/2005-109/