Eastern red bat
Lasiurus borealis
— Where the name comes from
Lasiurus is “hairy tail”, from the Greek lásios and ourá: in this genus the membrane between the hind legs is covered in dense fur on top, unusual among bats and decisive for an animal that sleeps in the open. Borealis is the Latin “of the north”, from the Greek Boréas, the north wind — the same that gives us the aurora borealis.
— Facts
- Group
- Mammals · Mammalia
- Order
- Bats
- Habitat
- Hanging in tree foliage, never in caves or buildings
- Range
- Eastern North America, migrating south seasonally
- Size
- 9–12 cm including tail, 33 cm wingspan, 7–16 g
- Diet
- Insectivore — moths and beetles, often around streetlights
- Lifespan
- Up to 12 years
— Characteristics
- 01
It sleeps hanging by a single foot among leaves, and looks like a dead leaf.
- 02
It bears up to five young, against the usual single one among bats.
- 03
It withstands the freezing of its surface tissues while hibernating in the open.
— What sets it apart
It spends the winter hanging from a tree or buried in the leaf litter, and lets itself freeze. Unlike almost every temperate bat, which seeks caves at a steady temperature, this species hibernates in the open and tolerates its surface tissues icing over, rewarming itself when the temperature climbs back above five degrees. The fur on the tail membrane, which it wraps around itself like a blanket, is what makes possible a choice no other North American bat makes.
