Shortcut to your favorite bat:

• Big Brown Bat
• Tri-colored Bat (formerly the Eastern Pipistrelle)
• Hoary Bat
• Indiana Bat
• Little Brown Bat
• Northern Long Ear Bat
• Eastern Red Bat
• Silver-Haired Bat
• Small-Footed Bat

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Big brown bats or the "Farmer's Friend" can be found during the day in certain barns and attics. At night they relentlessly feed over agricultural fields devouring crop pests.

The tri-colored bat is widespread in Pennsylvania but in low numbers. They are slow fliers and not often seen in the summer.

The Hoary is the largest bat found in Pennsylvania. It is only a summer resident; this bat may migrate 1,000 miles or more to overwinter.

A beautiful and powerful bat, the Hoary chooses deep forest habitat over man made structures.

The Indiana is the only federally endangered bat in Pennsylvania. Today 90% of the entire population survives the winter in just a handful of caves in the eastern United States.

Only a fraction of the historic Indiana bat population survives today. To make matters worse, they can be confused with common little brown and Northern long ear bats. The banded bat is an Indiana, how many more are there?

Little browns are the most common bats in North America. They have adapted to human alteration of the natural landscape by using certain manmade structures to roost.

Northern long ear bats are somewhat rare underground in Pennsylvania, but are commonly captured during the summer.

Longears sometimes prefer hibernating in narrow crevices and can be mistaken for little brown bats at a distance.

Red bats are migratory, disappearing far to the south as winter arrives. They are widespread and relatively easily captured during the summer.

Silver-haired bats are elusive forest dwelling migratory animals. A few are now known to hibernate at two sites in Pennsylvania.

A state threatened species, the Small footed bat is seen only in very cold caves in the winter and very rarely in the summer. A distinctive "raccoon mask" and small feet identify this bat.

Indiana Bat (Myotis sodalis)
The Indiana bat resembles the little brown bat, so much that the animal must be handled to closely examine differing characteristics. An Indiana bat has a pinkish cast to its fur, giving it a light purple-brown coloration. The muzzle has less fur giving its face a pink look compared to a little brown. The toes of the Indiana bat are distinctly curled and have short fine hairs which do not extend past the knuckles. A certain distinctive bulge on the edge of the tail membrane will complete a positive Indiana bat identification. Length, 2.9-3.7 inches; wingspread, 9.4-10.3 inches; weight, 0.18-0.28 ounces. Sexes are equal in size.

Indiana bats roost under the loose bark of trees in summer and have been found using buildings, roosting among common little browns. In winter, some 97 percent of the total species population hibernates in certain large caves in Missouri, Kentucky, Indiana, and Illinois. Pennsylvania is on the edge of the species' range. In our state in recent years, Indiana bats have been found wintering in only seven sites. The species has disappeared from all other known past localities. Populations of Myotis sodalis are dwindling throughout its range, and it is on the federal endangered species list.

The Indiana bat hibernates in clusters of about 250 bats per square foot on the ceilings and side walls of caves. In this formation, it is vulnerable to disturbance by cave explorers: when a bat on the edge of the cluster is awakened, it moves about, starting a ripple of activity that spreads throughout the group. A winter of repeated disturbances causes bats to burn vital fat stores, and they may run out of energy before spring.

Females of this species are believed to bear a single young in late June. Feeding habits are probably similar to those of the little brown bat. BatIndex

Little Brown Bat (Myotis lucifugus)
Pennsylvania's most common bat, the little brown is found statewide. Length, including tail, is 3.1-3.7 inches; wingspread, 8.6-10.5 inches; weight ranges from 0.25-0.35 ounces. Females are slightly larger than males. Color: a rich brown approaching bronze, usually with a dark spot on the shoulders. The fur is dense, fine, and glossy; the wings are black and bare.

This bat eats a wide variety of flying insects, including nocturnal moths, bugs, beetles, flies, and mosquitoes. Insects are regularly caught with the wing or tail membrane, and transferred to the mouth. An individual emerges from its day roost at dusk, and usually seeks a body of water, where it skims the surface for a drink, and then hunts insects. The little brown bat makes several feeding flights each night.

In October and November, bats leave their summer roosts and move to tunnels, mine shafts, and caves. Here, clinging to the ceilings and clustered against one another, they hibernate. In spring, they emerge in April and May. They return to the same hibernation sites year after year, usually to the same exact spot in the cave or mine.

Females disperse from the hibernation roosts, and gather in summer nursery colonies of 10 to l,000 individuals in attics, barns, and other dark, hot retreats. Males are solitary, roosting in hollow trees, under loose bark, behind loose siding and shingles, and in rock crevices.

A single young is born to each female in June or early July. After four weeks the young bat is fully grown and ready to leave the colony. Females mature sexually at about 8 months of age, while males mature in their second summer. Little brown bats may live up to 25 years. BatIndex

Northern Long Ear Bat (Myotis septentrionalis)
Similar in size and color to the little brown bat, A Northern long eared bat may be distinguished by its longer tail and narrow, long ears. It ranges throughout the state, but is much less common than the little brown bat; its distribution is considered local and irregular. Length, 3.0-3.7 inches; wingspread, 9.0-10.7 inches; weight, 0.25-0.32 ounces.

Zoologists have learned little of the ecology and behavior of Northern long eared bat; although they suspect feeding habits are similar to those of the little brown. Long eared bats roost singly or in small colonies in caves, behind window shutters, under loose tree bark, in cliff crevices. Females gather in nursery colonies in attics, barns, and tree cavities. Probably a single young is born in July. Long eareds return to caves in fall, often sharing space with little brown bats, big brown bats, and tri-colored bats. BatIndex

Red Bat (Lasiurus borealis)
A bright rusty coat and long, pointed wings distinguish this species. Length is 3.7-4.8 inches; wingspread, 11.3-12.9 inches; and weight, 0.28-0.49 ounces. Individuals roost singly in trees (except for females with young), often on forest edges, in hedgerows, and shrubby borders; they seem to prefer American elms. Rarely do they use caves or buildings.

Red bats start flying early in the evening, preying on moths, flies, bugs, beetles, crickets, and cicadas, which they take from air, foliage, and ground. Strong fliers, red bats are considered migratory, although their migratory patterns are little known. The sexes may migrate separately. Red bats start flying south in September or October. BatIndex

Females bear 1-5 young (usually 2-3) in their treetop roosts. For the first few days, the young remain clinging to their mother when she flies out to hunt. Young are able to fly at 3-4 weeks, and are weaned at about 5-6 weeks old. Longevity is about 12 years . The red bat ranges across Pennsylvania.

Silver-Haired Bat (Lasionycteris noctivagans)
A medium-size bat: length, 3.7-4.5 inches; wingspread, 10.512.1 inches; weight, 0.25-0.35 ounces. The fur is soft and long; the sexes are colored alike, blackish-brown tipped with white, for a bright, frosted appearance.

The silver-haired bat inhabits wooded areas bordering lakes and streams. It roosts in dense foliage, behind loose bark, or in a hollow tree-rarely in a cave. It begins feeding earlier than most bats, often before sunset. Silver-haired bats do not hibernate in Pennsylvania, migrating farther south. In summer, a few may breed in the cooler, mountainous sections of the state, but most go farther north. BatIndex

Small-Footed Bat (Myotis leibii)
Also known as Leib's bat, this species is one of the smallest in North America: length, 2.8-3.3 inches; wingspread, 8.3-9.7 inches; weight, 0.18-0.28 ounces. In Pennsylvania, it is rare, and the population is thought to be decreasing; it is classified as a threatened species.

The small-footed bat resembles the little brown bat, but has a golden tint to its fur. Besides somewhat ill-proportionated small feet and forearms, this bat has a distinctive black "raccoon mask". Feeding and breeding habits probably parallel those of the other small, closely related bats. The small-footed bat waits until November to enter caves for hibernating, and emerges in March. It hibernates in narrow cracks in the wall or roof, singly and in small groups. It usually stays close to entrances or in areas where the temperature is just above freezing. BatIndex

Note: The seminole bat (Lasiurus seminolus) and evening bat (Nycticeius humeralis) have been found a few times in Pennsylvania, but are considered incidental.

This information is adapted from the Pennsylvania Game Commission's Wildlife Note #175-35. Other Wildlife Notes on other animals are available through PGC, Bureau of Information and Education, Dept. MS, 2001 Elmerton Avenue, Harrisburg, PA 17110-9797.