"Bats in the Attic. This is the term used most often by our customers calling to seek
help with a bat issue. In most cases, however, the bats are not actually populating the
attic proper. Bats only need a small opening, roughly a quarter inch, to gain entry to
the gaps between the inside wall of a structure and the exterior fascia. In almost
every instance, the bats will take up residence in a gap that is located outside of the
attic space. Having said that, it does not rule out the possibility that a confused
(usually young) bat has crawled through a twenty foot maze of gaps and now finds
itself hanging from the wall of your livingroom.
The Bats of Florida. Brazilian Freetail Bats (Tadarida
brasiliensis) and Evening Bats (Nycticeius humeralis)
are the two most common colonizing bats we deal
with in Central Florida. In total, there are 13 species
of bats found in Florida. Some bats are year round
residents while others simply visit seasonally.
Free-tail and Evening Bats will typically choose a
manmade structure in which to colonize. Their
colonies can quickly populate to numbers from the
hundreds all the way up to thousands of members.
Along with the noise of the bats crawling across
wooden surfaces comes some very serious health
risks associated with the accumulations of urine and
• Bats are insectivores dining mainly on moths and flies. Some larger colonies
have been estimated to consume thousands of pounds of insects per night.
• Life span in most cases is 12 to 25 years, but some species of bats can exceed
• Home range is typically within several hundred yards of the home colony.
• Florida adult bats normally measure less than 3 inches in body length with a
wingspan of 13 inches.
• Baby bats are born in the summer months, usually in early June. Most species
of bats produce one live offspring per year. This slow reproductive rate is the
cause for much legislation to protect the species.
More on The Bats of Florida: Brazilian Freetail Bats (Tadarida brasiliensis) and
Evening Bats (Nycticeius humeralis).
Bats are a vital part of our lives in Florida and should be appreciated. They are
intelligent, shy creatures that quietly work at making our lives less troubled by
consuming literally tons of flying insects each night. Each bat will consume its own
bodyweight in insects per outing.
Bats do not dive-bomb humans and get stuck in your hair. On a warm summer
evening, have you ever noticed a small squadron of gnats or mosquitos circling
above your head or that of a companion? That is exactly what the bat is after...not
you, your hair, or your jugular.
Bats are not blind. Their eyesight is comparable to that of our own. They supliment
their vision by using a form of echolocation that enables them to hunt and
maneuver at incredible speeds.
Noise: A very high pitched squeaking or chirping sound is often the first tip to
the home owner that something has moved into the roof area. Sometimes the
movement of the bats can be detected as a scratching or scurrying sound.
Structural Damage: In order to enter the void in which the colony lives, bats
will exploit any openings 1/4" or bigger that leads to that space. Over time one
or two openings in particular will become the main points of entry and exit. As
the bats travel over that spot time and time again, they will leave a grease trail
that can easily be viewed from the ground. These stains are often the first sign
that a significant colony exists within your structure.
The damage caused by having dozens, hundreds, or thousands of bats existing
in a confined space within a structure can be easily imagined. Although they tend
to evacuate on the way out of the roost site and again on the way in, they still
spend a large portion of the day pooping and urinating within your wall space.
They also possess a scent gland that produces a very musky, almost chemical,
odor that can help identify the roost site.
Droppings: The droppings left by the colony can be extremely dangerous to
humans. Bat guano is known to carry a fungus that can have serious respiratory
effects on humans. A decontamination of the effected area is recommended
Recurrence: A structure that is not treated properly can expect to have a
reinfestation in very short order.
Exlusion: The best and only legal means of dealing with a bat infestation. All
secondary entry points are sealed prior to removing the colony. These points, if
untreated, would allow the bats to re-enter after they are evicted. Once the
secondary gaps are sealed, the colony can be removed through the installation
of a one-way exclusion device that will allow the colony to exit for a food and
water source but prevents re-entry. All bats will leave exit the site within four
days, the device can be removed, the final hole sealed and the clean-up can
Copyright Wildlife Ranger 2014