RALEIGH — The N.C. Wildlife Resources Commission is offering bat-friendly tips to homeowners now that pup-raising season is underway.
The beginning of May through the end of July marks the timeframe when female bats are raising their young — called pups. Commission biologists urge homeowners to avoid closing up holes or installing eviction devices during this time, as young bats, like other mammals, depend on their mother for survival during the first few weeks of life.
“If a homeowner installs an eviction device or covers up the holes that bats have used to get into the house, female bats may not be able to get to their young after a night of feeding, and the young bats would starve to death,” said Jessie Birckhead, the commission’s wildlife extension biologist. “If any bats are sealed inside, including pups that can’t fly, they will search for a way out and may find their way into the homeowner’s living space.”
Although it only takes roughly seven weeks for a young bat to attain the ability to fly, different species of bats give birth to live young at different times, hence the three-month range.
“As long as bats can’t get into the living space, homeowners should find that it is best to let the female bat finish rearing its pups before excluding the bats from the building,” Birckhead said.
Once the pup-rearing season has ended in late July, Birckhead advises homeowners to determine how bats are entering the house and permanently seal all potential entry points.
“Look for small holes, cracks in siding or fascia, tiny spaces around utility boxes — all these places can allow a bat to get inside your home,” Birckhead said. “If any bats are present, you need to install eviction devices that allow the bats to leave but prevent them from coming back into your home. Once eviction devices have been up for a week and all bats have left, the follow-up work of permanent exclusion must be completed.”
Bat exclusion devices can be purchased or made from PVC pipe. More information on bat exclusion guidelines is available on Bat Conservation International’s website.
People who would rather hire a professional to exclude bats from their homes can find a wildlife damage control agent in their area by visiting www.ncwildlife.org and clicking on the “Have a Wildlife Problem” link on the left side of the page.
Bats return to the same roosts each spring, so it is important not only to maintain your home after excluding bats, but also to help displaced bats find alternate roosting spaces when they return. Homeowners can erect bat boxes near their homes. Place bat boxes on a pole or a building, not a tree, and at least 10 feet high in a place with at least seven hours of direct sunlight in the summer.
“Tree limbs prevent direct sunlight on the box, make bats more vulnerable to predators, and obstruct flight when entering and exiting the box,” said Brandon Sherrill, the Commission’s mammologist.
For tips on building, buying, or installing bat boxes see http://www.batcon.org/resources/getting-involved/bat-houses.
While bats are warm and fuzzy, most people do not have warm and fuzzy feelings about them – despite the fact that they play a crucial role in our ecosystem. All bat species that reside in North Carolina feed voraciously on insects, consuming close to their body weight each night. Many of the insects bats consume are very damaging to agriculture crops. In other parts of the world, bats serve as important pollinators for fruits that humans consume every day, such as bananas and mangos. Still others serve as seed-dispersers for a wide variety of foods, from avocados to cashews.
Helping bats, whether by setting up a bat box or avoiding the use of eviction devices during pup-rearing season, can do much to offset problems bats are facing today. However, the biggest and most serious threat to bats is white-nose syndrome, a fungus that invades and destroys the tissue of bats during the winter, killing anywhere from 70 to 100 percent of bats in a colony. Biologists first detected WNS in North Carolina in a bat from Avery County in 2011, and since that time, the disease has stricken five bat species in 10 counties in western North Carolina. Although WNS does not affect humans or pets, its effects on bat colonies have been devastating.
People can do many things to help bat populations in North Carolina. In addition to installing bat boxes, they can:
• Plant native plants that attract insects to provide food for bats
• Limit the use of insecticides and herbicides whenever possible
• Avoid disturbing hibernation areas and maternity colonies
• Join a conservation group, such as Bat Conservation International, to stay up to date on bat conservation efforts
• Educate yourself and others regarding the importance of bats and why they are beneficial.
“Now more than ever, bat populations need our help,” Sherrill said. “When you see a bat, don’t panic. As with all wildlife, we always advise people to leave bats alone. They’re a natural and important part of our ecosystem.”
Read more tips on co-existing with bats and other wildlife, and learn more about bats in general by visiting the Commission’s Conserving page.