During the cold winter, some bats migrate to a warmer area. Some bats (like the brown bat) hibernate during the cold of winter, sleeping very deeply until warm weather arrives.

Anatomy: Bat's wings are long fingers covered by thin skin. They have furry bodies. Some bats have short tails, other have no tail. Bats have weak legs and don't walk very well. The smallest bat is the bumblebee bat (with a wingspan of 6 inches=15 cm, weighing less than a penny); the biggest bat is the flying fox bat (with a wingspan of 6 feet=1.8 m, weighing 2 pounds=1 kg).

Senses/Diet: Bats can see, but do not use this as their primary sense.

There are two types of bats that differ in their diet and in the way they sense and obtain food. Bats are divided into:

• Microchiropterans: These bats use echolocation to find insects and small animals to eat. While flying, these bats send out high-pitched sounds that bounce off other objects. The bat listens for the bounced sound, and can determine where objects are located. People cannot hear these high-pitched sounds. Some Microchiropterans include the vampire bat, the frog-eating bat, etc. The vampire bat is the only bat (and the only mammal) that eats blood. It makes a small hole with its two very sharp incisor teeth and laps up the blood, which doesn't clot because of anti-coagulants in the bat's saliva.
• Megachiropterans: These large bats use the sense of smell to find their food, fruit and/or nectar. Some Megachiropterans include the fruit bat, the blossom bat, etc.