Call us to have an extensive bat inspection done. We will determine if there is a need to have the bat guano removed in the attic, which cracks have to be sealed and which cracks need bat traps installed. After bat cones are installed, they stay in place for about 3 to 4 weeks. This allows all the bats to leave the building and find a different place to live. We then remove the bat cones and seal these entrances. If you catch a bat inside, it is recommended to save the bat for rabbi testing even if you don’t think you have been bitten. Many times you don’t even feel the bite or scratch. Testing is needed especially if children are living in the house.
Little brown bat (Myotis lucifugusJ Recognition
forearm -1.34 to 1.61 inches (3.4 to 4.1 em)
wingspan – 9.02 to 10.59 inches (22.9 to 26.9 cm)
ears – 0.55 to 0.63 inches (1.4 to 1.6 cm)
foot – approximately 0.39 inches (1.0 cm); long hairs on toes extend be- yond claws.
Pale tan through reddish brown to dark brown, depending on geo- graphic location. The species is a rich dark brown in the eastern United States and most of the west coast. Fur is glossy and sleek.
Confusion may occur with a few other “house” bat species. In the East, it may be confused with Keen’s bat (M. keenii), which has longer ears [0.69 to 0.75 inches (1.7 to 1.9 em)] and a longer, more pointed tragus (the appendage at the base of the ear). In the West, it resembles the Yuma myotis (M. yumanensis), which has dull fur and is usually smaller. However, the Yuma myotis and little brown may be indistin- guishable in some parts of the northwestern United States where they may hybridize.
This is one of the most common bats found in and near buildings, often located near a body of water where they forage for insect prey. Summer colonies are very gregarious, com- monly roosting in dark, hot attics and associated roof spaces where maternity colonies may include hundreds to a few thousand individuals. Colonies may also form beneath shingles and siding, in tree hollows, beneath bridges, and in caves. Litter size is 1 in the North- east; twins occasionally occur in some other areas. The roost is often shared with the big brown bat (E. fuscus) though the latter is less tolerant of high temperatures; M. keenii may also share the same site. Sepa- rate groups of males tend to be smaller and choose cooler roosts within attics, behind shutters, under tree bark, in rock crevices, and within caves.
In the winter, little brown bats in the eastern part of their range abandon buildings to hibernate in caves and mines. Such hibernacula may be near summer roosts or up to a few hundred miles (km) away. Little is known of the winter habits of M. lucifugus in the western United States.
The life span of little brown bats has been established to be as great as 31 years. The average life expectancy, however, is probably limited to only a few years.
Big brown bat (Eptesicus fu,scus) Recognition
forearm – 1.65 to 2.01 inches (4.2 to 5.1 em)
wingspan – 12.80 to 13.78 inches (32.5
to 35.0 cm)
ears – with rounded tragus
From reddish brown, copper colored, to a dark brown depending on geographic location. This is a large bat without distinctive markings.
Confusion may occur with the evening bat (Nycticeius humeralis) though the latter is much smaller.
This hardy, rather sedentary species appears to favor buildings for roost- ing. Summer maternity colonies may include a dozen or so and up to a few hundred individuals, roosting behind chimneys, in enclosed eaves, in hollow walls, attics, barns, and behind shutters and unused sliding doors. They also form colonies in rock crevices, beneath bridges, in hoHO’VV trees, and under loose bark. Litter size is 2 in the East to the Great Plains; from the Rockies westward 1 young is born.
The big brown bat is one of the most widely distributed of bats in the United States and is probably familiar to more people than any other species. This is partially due to its large, easy-to-observe size, but also to its ability to overwinter in buildings (attics, wall spaces, and basements). Its close proximity to humans, coupled with its tendency to move about when temperature shifts occur, often brings this bat into human living quarters and basements in summer and winter. Big browns also hibernate in caves, mines, storm sewers, burial vaults, and other underground harborage. While E. fuscus will apparently travel as far as 150 miles (241 km) to hibernacula, the winter quarters of the bulk of this species are largely unknown.
Big brown bats may live as long as 18 years.
Bats in North America are virtually all insectivorous, feeding on a variety of flying insects (exceptions among house bats were noted previously). Many of the insects are harmful to humans. While there must be some limitations based on such factors as bats’ body size, flight capabilities, and jaw opening, insectivorous bats apparently consume a wide range of prey (Barbour and Davis 1979). The little brown bat’s diet includes mayflies, midges, mosquitoes, caddis flies, moths, and beetles. It can consume insects equal to one-third of its body weight in 1/2 hour of foraging. The big brown bat may fill its stomach in about 1 hour (roughly 0.1 ounce per hour [2.7 g/hr]) with prey including beetles, moths, flying ants, true bugs, mayflies, caddis flies, and other insects. The nightly consumption of insects by a colony of bats can be extremely large.
General Biology, Reproduction, and Behavior
Most North American bats emit high frequency sounds (ultrasound) inaudible to humans and similar to sonar, in order to avoid obstacles, locate and capture insect prey, and to communicate. Bats also emit audible sounds that may be used for communication between them. Bats generally mate in the fall and winter, but the female retains the sperm in the uterus until spring, when ovulation and fertilization take place. Pregnant females may congregate in maternity colonies in buildings, behind chimneys, beneath ridges, in tree hollows, caves, mines, or other dark retreats. No nests are built. Births typically occur from May through July. Young bats grow rapidly and are able to fly within 3 weeks. Weaning occurs in July and August, after which the nursery colonies disperse.
Bats prepare for winter around the time of the first frost. Some species migrate relatively short distances, whereas certain populations of the Mexican free-tailed bat may migrate up to 1,000 miles (1,600 km). Bats in the northern United States and Canada may hibernate from September through May. Hibernation for the same species in the southern part of their range may be shorter or even sporadic. Some may fly during warm winter spells (as big brown bats may in the northeastern part of the United States). Bats often live more than 10 years.
In response to a variety of human activities, direct and indirect, several bat species in the United States have declined in number during the past few decades. Chemical pesticides (par- ticularly the use of persistent and bioaccumulating organic pesticides) have decreased the insect supply, and contaminated insects ingested by bats have reduced bat populations. Many bats die when people disturb summer maternity roosts and winter hiber- nacula. Vandals and other irrespon- sible individuals may deliberately kill bats in caves and other roosts. Even the activities of speleologists or biolo- gists may unintentionally disturb hibernating bats, which depletes fat reserves needed for hibernation Modification and destruction of roost sites has also decreased bat numbers. Sealing and flooding of mineshafts and caves and general quarrying operations may inadvertently ruin bat har- borages. Forestry practices have reduced the number of hollow trees available. Some of the elimination of natural bat habitat may contribute to bats roosting in buildings.
Public Health Issues Rabies-General Epidemiology. Bats are distinct from most vertebrate pests that inhabit human dwellings because of the potential for transmitting rabies a viral infection of mammals that is usually transmitted via the bite of an infected animal. Rabies does not respond to antibiotic therapy and is nearly always fatal once symptoms occur. However, because of the long incubation period (from 2 weeks to many months), prompt vaccination following exposure can prevent the disease in humans. Dogs, cats, and livestock also can be protected by periodic vaccinations.
Bats are not asymptomatic carriers of rabies. After an incubation period of 2 weeks to 6 months, they become ill with the disease for as long as 10 days. During this latter period, a rabid bat’s behavior is generally not normal-it may be found active during the day- time or on the ground incapable of flying. Most human exposures are the result of accidental or careless handling of grounded bats. Even less frequently, bats in this stage of illness may be involved in unprovoked attacks on people or pets (Brass, pers. commun.; Trimarchi et al. 1979). It is during this stage that the rabid bat is capable of transmitting the disease by biting another mammal. As the disease progresses the bat becomes increasingly paralyzed and dies as a result of the infection. The virus in the carcass is reported to remain infectious until decomposition is well advanced.
SignifICance. Rabies is the most important public health hazard associated with bats. Infection with rabies has been confirmed in all 40 North American species of bats that have been adequately sampled in all of the contiguous United States and in most provinces of Canada.