Bats
Flying mammal in the Chiroptera order
Introduction
Bats are found in almost every habitat world wide. Different species select different habitats during different seasons ranging from mountains, beaches and deserts. Bat habitats have two requirements: a place were they can spend their day in roost (hibernate), and places they can rummage for food. Bat habitats can be found in tree-hollows, crevices, foliage, and even human-made structures
Bats are mammals they have hair, produce body heat, and nurse their young but unlike other mammals’ bats fly. They can live up to 30years and most species only produce one offspring per year. Contrary to popular belief bats are of little threat to people who do not handle them, they are shy, and are considered to be important to our ecosystem and beneficial to humans. One benefit bats provide is pest control. Worldwide bats are the most important natural predator of night flying insects. One Myotis lucifugus (California little brown bat) can eat 600 mosquitoes per hour. Other species of bats are known to eat up to 250 tons of insects nightly. Bat houses are often installed nearby a home or business to provide a safe place for bats that have been evicted from elsewhere. Nectar-feeding bats are important to the desert ecosystem because they are primary pollinators of giant cacti.
Only four out of twenty-four bat species tolerate living near humans and can often be found in buildings: the Mexican free-tailed bat, the Yuma myotis (Myotis yumanensis), the little brown bat, and the big brown bat. There are six bat species occasionally found in buildings: the western mastiff bat (Eumops perotis), the pallid bat (Antrozouspallidus), Townsend's big-eared bat (Corynorhinus townsendii), the long-eared myotis (Myotis evotis), the fringed myotis (Myotis thysanodes), and the long-legged myotis (Wyotis volans).
Bats will take up occupancy in/or around human homes, such as: attics, or hang under the eaves (or other structures) for two reasons: one, because the sturucture provides a safe resting place similar to their natural roost(ing) place and second, because neighborhoods provide bug-attracting lights, ponds, or open areas for bats to forage over and around. All that flying around catching insects requires much energy so bats need to spend much of their time resting. Periods of inactivity (torpor) are spent in roost. Roosts are a place of protection from predators and extreme temperatures. The bats hanging from your roof, attic, etc., are probably dayroosting because they have found a safe environment to rest while regaining energy for nightly activity or as a maturity roost to keep their young safe from danger. The bats that hang above your stoop at night are more then likely night-roosting for a few hours’ in-between meals.
Although bats provide insect control it is recognized that the presence of bats can be somewhat disturbing. If a bat is inside your home try to eradicate it by closing the interior doors and open all exterior windows and doors in the area containing the bat. If you must capture a bat wear leather gloves and place the bat in a container to relocate it to the outdoors. Under California law, propriety owners &/or employees may legally remove bats that are causing damage to the property. However, it is illegal to posses &/or capture bats for any other reason without a permit from the Department of Fish and Game. Be aware of illegal pest control companies wanting to fumigate &/or poison bats to kill them. Not only is poisoning, fumigating, &/or killing bats illegal under both state and federal laws these practices do not rectify the problem and can be costly. The best way to get rid of bats is to remove or wait for the bats to leave their roost and then permanently seal up any access points. However, this exclusion technique should never be used during maternity season (beginning of April to September) when young cannot take care of themselves. Excluding bats from roosts with young present could make the problem worse with the bugs and the smell of baby bats dying.
Bat roost
West Valley Mosquito and Vector Control District