A bat house built in my back yard in 2004 remained vacant until this year. The house has room for 600 bats, but only eleven moved in. The house is near three large stock ponds. Dragonflies and hummingbirds find plenty of insects to eat during the day, so it seems reasonable to expect the site can support more than eleven bats.
The photograph of a Hoary Bat was published by M. Siders (BLM), 2006. “Bats of the Grand Staircase-Escalante National Monument”, poster.
Bats are encouraged in many places because they eat insects and pollinate plants. Austin, Texas, for instance, is proud of its large bat population, and refers to itself as Bat City. I am anxious to see bats increase because they eat mosquitoes, my personal nemesis. Bats are good with mosquitoes. Little Brown Bats, for example, can eat 1,000 mosquitoes per hour. Perhaps other mammals in the neighborhood will benefit from having more bats.
Arizona’s 28 bat species represent more than half the species found in all the United States. The checklist below provides names and Internet links to detailed information (use ‘control click’ to activate link).
Bats are sensitive to many human activities and are injured by some. One of the most damaging human activities is the application of pesticides that eliminate essential bat food. Another dangerous activity is construction of tall structures, especially wind turbines, that kill large numbers of bats. In recent years, a fungal disease, white-nose syndrome, has spread across the northeastern United States. The disease organism is endemic to Europe, and was probably accidentally brought to the U. S. by people. The disease has caused 100 percent mortality in some sites. Now that the disease is present on the North American continent it will probably spread to Arizona.
My preliminary literature review suggests that European bats are immune to white fungus disease. Any survivors of the initial onslaught of the disease in the U. S. may form resistant populations. Thomas Kunz suggested one way to help the bats survive would be to build more bat houses (Genoways 2011). Bat houses are constructed with narrow (¾”) roosting spaces. Bats pack into the spaces and their shared body heat can keep temperatures above the tolerance level of the fungus. Bat houses like mine, built using the pattern provided by Tuttle and Hensley (2000), might eventually preserve significant colonies.
Numbers (species identified/probable total)*
US & Canada
AZ Spp. at Risk
* Data from AZGDF and the Organization for Bat Conservation
Checklist information was compiled from the Arizona Game and Fish Department website and other sources in the Reference list. Species links are to the Smithsonian National Museum of Natural History. There you will find photographs, range maps, and detailed information.
Symbols in the left check box: E = Endangered (U. S. Endangered Species Act), NT = Near Threatened (World Conservation Union, formerly the IUCN), S = Sensitive species (U. S. Forest Service).
|Arizona Bats (Chiroptera)|
|Molossidae (Free-tailed Bats)|
|S||Greater Western Mastiff Bat (Eumops perotis californicus)|
|Western Mastiff Bat (Eumops perotis)|
|NT||Underwood’s Mastiff Bat (Eumops underwoodi)|
|S||Pocketed Free-tailed Bat (Nyctinomops femorosaccus)|
|Big Free-tailed Bat (Nyctinomops macrotis)|
|NT||Brazilian Free-tailed Bat (Tadarida brasiliensis)|
|Mormoopidae (Ghost-faced Bats)|
|Ghost-faced Bat (Mormoops megalophylla)|
|Phyllostomidae (Leaf-nosed Bats)|
|S, NT||Mexican Long-tongued Bat (Choeronycteris mexicana)|
|E||Southern Long-nosed Bat (Leptonycteris yerbabuenae) (Leptonycteris curasoae)|
|S||California Leaf-nosed Bat (Macrotus californicus)|
|Vespertilionidae (Vesper Bats)|
|Pallid Bat (Antrozous pallidus)|
|S||Townsend’s Big-eared Bat (Corynorhinus townsendii)|
|Big Brown Bat (Eptesicus fuscus)|
|S||Spotted Bat (Euderma maculatum)|
|S||Allen’s Big-eared (or Lappet-Browed) Bat (Idionycteris phyllotis)|
|Silver-haired Bat (Lasionycteris noctivagans)|
|Western Red Bat (Lasiurus blossevillii)|
|Red Bat (Lasiurus borealis)|
|Hoary Bat (Lasiurus cinereus)|
|Southern Yellow Bat (Lasiurus ega)|
|S||Western Yellow Bat (Lasiurus xanthinus)|
|Southwestern Myotis (Myotis auriculus)|
|California Myotis (Myotis californicus)|
|Western Small-footed Myotis (Myotis ciliolabrum)|
|Long-eared Myotis (Myotis evotis)|
|Little Brown Bat (Myotis lucifugus)|
|Fringed Myotis (Myotis thysanodes)|
|Cave Myotis (Myotis velifer)|
|Long-legged Myotis (Myotis volans)|
|Yuma Myotis (Myotis yumanensis)|
|Western Pipistrelle (Pipistrellus hesperus)|
American Society of Mammalogists: http://www.mammalsociety.org,
Arizona-Sonora Desert Museum: http://www.desertmuseum.org/pollination/bats.php.
Bats. Kunz Bat Lab: http://www.bu.edu/cecb/BATS/.
Bat Conservation International: http://www.batcon.org/.
Genoways, Ted. August 30, 2011. The Man Who Loved Bats. On Earth News: http://www.onearth.org.
Hoffa, R.L., and W. Anderson. 1996. Coexisting with urban wildlife: A guide to the central Arizona uplands. Sharlot Hall Museum Press, Prescott, AZ. 123 p.
Kays, R.W., and D.E. Wilson. 2009. Mammals of North America (second edition). Princeton University Press, Princeton, NJ. 248 p.
National Wildlife Federation: www.nwf.org.
Organization for Bat Conservation: http://www.batconservation.org/
Tuttle, M.D., and D. L. Hensley. 2000. The bat house builder’s handbook. Bat Conservation International, Austin, TX. 36 p.
U. S. Endangered Species Act. 1973. The act and related laws are discussed at: http://www.fws.gov/laws/lawsdigest/ESACT.html.
U. S. Fish and Wildlife Service: http://www.fws.gov.
U. S. Forest Service. 2007. Regional Forester’s list of sensitive animals: http://www.fs.usda.gov/Internet/FSE_DOCUMENTS/fsbdev3_021328.pdf.
Western Bat Working Group: http://www.wbwg.org/index.html.
World Conservation Union: www.iucn.org .