Bats are shy mammals that like to fly around at night. They're also really cute.
Experience Bonus 
A +10% experience bonus is applied to bats who are housed in the following habitats:
Meadow · Ice · Savanna · Cliffs · Bamboo Grove · Swamp · Tundra · Snow · Wasteland · Halloween · Christmas · Valentine's · Terrarium · Easter · Birthday · Winter Wonders
Attractiveness Bonus
A +10% attractiveness bonus is applied to bats who are housed in the following habitats:
Easter Egg
Bats placed in the Ice Habitat have their tree covered in ice and become frozen bat-icicles!
Ice Covered Bats