Life in the Cave

Little Brown Bats:

Little Brown Bats are the most abundant type of bat in the United States.  They are 4.5 to 5.5 inches in length and weigh 5-13 grams.  These bats feed on insects using echolocation to find them.  Moths, wasps, beetles, gnats, and mosquitoes are among their favorites.  When feeding they can fill their entire stomach in as few as 15 minutes.  During the winter the bats come to the cave to hibernate.  Throughout the winter their heart rate slows to only five beats per minute, and they only take one breath every three to five minutes.  In the spring they end their hibernation, and the females give birth to one pup, although there are sometimes twins.  These bats can live for up to 33 years if the conditions are suitable for them.

Eastern Pipistrelle Bats:

Eastern Pipistrelles are some of the smallest bats in North America.  They weigh only four to eight grams.  These bats also head to caves in the winter to hibernate.  They will often return to the same hibernation location year after year.  Much like Little Brown Bats, Eastern Pipistrelles use echolocation to locate small insects.  They can eat these insects at a rate of up to two insects per second, and sometimes increase their body mass by 25% in only a half hour by feeding.  In the spring the females give birth to twin pups.  The male Eastern Pipistrelles can live up to 15 years, and the females up to 10 years.

Northern Myotis Bats:

Northern Myotis Bats are also found in Crystal Cave.  Like the Eastern Pipistrelles, they are small, weighing only 5-10 grams.  They are characterized by their long ears.  These bats choose to feed primarily on moths, but also eat other insects using echolocation.  During their hibernation in the winter they choose to roost by themselves, as opposed to in groups.  After hibernation the females give birth to a single pup.  Northern Myotis Bats can live to 18 years of age.

The Bats We Saw