Bats . . . Backyard Buddies on Monday, August 02, 2010

If West Nile virus made mosquitoes the enemy, then bats should be our new best friends! The common Little Brown Bat eats about 500 mosquitoes per hour. Multiply that by a colony of 30 or more, and we’re talking serious pest control. These flying mammals are also important agents of seed dispersal and pollination.

Have no fear!  Bats have an undeserved bad reputation.  Fewer than 1% of North American bats have rabies, the same percentage as other mammals.  Bats don’t tangle in people’s hair: a close-flying bat is likely catching insects buzzing around you.

“Winged Hamsters”:  Bats are docile animals, dubbed “winged hamsters” by one biologist.  “Blind as a bat” doesn’t apply, since they actually see quite well.  All 15 species of Oregon bats are insect eaters.

Bats are remarkable creatures.  Bats are mammals, and thus are furred, warm-blooded, and nurse their live-born young.  Biologists classify bats in their own order:  Chiroptera, or “winged hand”.  It’s a good description since the struts of a bat’s wing are its long, spidery finger bones.  Bats are the only mammals that actually fly, rather than glide.

Bats locate prey and avoid obstacles using echolocation.  Bats emit high-pitched sounds and listen for echoes to sense objects in darkness.  Many species of bats have evolved long ears or other curious facial features which enhance their ability to listen for those echoes.

A range of private and government entities encourage bats for low- cost, environmentally friendly insect control.  For example, bat boxes have been used for years in vineyards from France to Napa Valley.  Some bats help to pollinate the grape crop, while others eat insects that would otherwise attack the grapes.

In the Portland metro area, Little Brown Bats occupy the largest percentage of bat houses.  Big Brown Bats may share the same house. Why not encourage these beneficial creatures?

Bat House Placement Tips
  * Larger bat houses tend to be more popular
  * Locate near a small body of water when possible
  * Choose a south to southeastern exposure with 6 – 8 hours of sun
  * Mount the box 12 – 15 feet high, sheltered from wind
  * Entrance should be free of branches or other obstructions
  * Consider painting it in a dark, water-based stain or paint to help it hold in heat