Are Bats Harmful?
Do bats hurt people?
Few bats will come in contact with humans. Bats are elusive and prefer habitats away from direct contact with humans. Interactions can occur when a stray bat enters a living space or when encountered nesting in areas such as attics.
Bats can enter structures to avoid elements and predators. Colonial or social bats can also start a colony in a house. Usually, bats enter through roof edges, vents, improperly flashed roof valleys, gable ends, chimneys or siding.
Bats can cause damage to structures. While the bats typically roost in attics or walls in structures, bat colonies have been found in sewers, mausoleums, utility, power sheds and even water wells. Bats may interfere with the operation of utilities if they block water pumps or contaminate water.
Bats can also create unsightly rub marks where they exit their roosting area. These rub marks, which are usually due to the body oils of the bats, may contain some hairs as well. The rub marks are dark and contrast with light colored wood or siding.
Bats do commonly give off a high pitched chirp that younger people can hear. Besides the chirping, the colony can give off a rustling sound both during the day and when they are preparing to emerge for a night of feeding.
Bats deposit droppings and urine. Bat droppings are called guano that is harvested in some parts of the world and is used for fertilizer. Guano may act as a growth medium for microbes, including those that can cause disease such as histoplasmosis. Urine can cause a slipping safety hazard on floors and may seep into living spaces if a colony is overhead. Urine evaporates quickly and leaves a crystalline residue.
Rabies is another health threat associated with bats. Note that rabid bats are rare, but this is a good reason why handling bats should only be done by a wildlife professional.
As with any wild animal which lives in our structures, bats can cause some damage and can carry and spread disease. Care must be taken when working in bat infested areas; however, transmittal of disease from bats is not as common as folklore suggests.