17 April: Bat Appreciation Day

10 facts about bats for Bat Appreciation Day.

1. There are more than 1,100 species of bats in the world. They account for about a quarter of all mammal species and are found on every continent except Antarctica. The UK has 16 different types of bat.
2. The world’s largest bat is the "flying fox". It lives on islands in the South Pacific and has a wingspan of up to 6 feet. The smallest is the bumblebee bat or Kitti’s Hog-nosed Bat, which lives in Thailand. It is about the size of a bumblebee, and weighs less than a US one cent coin. It may be the smallest existing mammal.
3. Bats aren't blind. Yes, they use echolocation to find food and avoid obstacles in the dark, but they can see, too, and some species can see ultraviolet light. A bat can emit 10-20 echolocation beeps per second, and can use it to detect objects as thin as a human hair.
4. Bats are the only mammals which can fly. Some bats can fly up to 250 miles (402 km) in a single night. They can fly up to 10,000 feet (3,048 m) high and reach speeds up to 60 miles per hour (97kph). Their wings are long finger bones covered by thin layers of skin. The wing membranes of a bat make up about 95% of its body surface area; so helps the bat regulate body temperature, blood pressure, water balance, and gas exchange.
5. They don't breed anything like as fast as other mammals of a similar size - a female bat will only have one pup a year, and usually, all the female bats in a colony have their babies at the same time. Bat mothers can find their babies among thousands or millions of other bats by their unique voices and scents. They live much longer, too - they can live for over 30 years.
6. They don't suck Blood. Only three species of bat live on blood, and these "vampire" bats don't suck, but bite and then lap up the blood. Some white-winged vampire bats snuggle up to hens and pretend to be chicks. Once in position under the hens, the bats feed on their blood. They sometimes feed other bats by returning to the roost and sharing their meal by vomiting it. Scientists in several countries are trying to copy the enzymes found in vampire bat saliva to treat Heart conditions and strokes in humans.
7. Most bats eat insects or fruit, although a few eat smaller mammals or Frogs. Bats can eat up to 1,200 Mosquitoes in an hour and often consume their body weight in insects every night. Some seeds will not sprout unless they have passed through the digestive tracts of a fruit eating bat. The bats which eat frogs can tell the difference between safe and poisonous frogs by listening to the male frog’s call. There is a bat which lives on nectar, the tube-lipped nectar bat (Anoura fistulata). It has the longest tongue, relative to body length, of any mammal. When it's not eating, the bat retracts its tongue into its rib cage.
8. Bats do spend a lot of time hanging upside down. They rest, sleep, mate and give birth in this position. Most bats roost in caves or buildings although there is a species in Asia which roosts inside Bamboo stalks, and one in Africa which roost in Spiders' webs. The largest bat colony in the world is in Texas. Over 20 million bats live in the Bracken Bat Cave. That's more bats than there are people living in Mumbai, India. Some bats migrate for the winter, while others hibernate. During hibernation their heartbeats slow right down and they live off fat stored in their bodies. The mouse-eared bat has a heartbeat as low as 18 beats a minute during hibernation, compared to 880 when it is active. In their hibernation state, bats have been able to survive freezing temperatures and even being encased in ice.
9. Before they found oil, the biggest export of Texas was bat guano. Bat droppings are rich in nitrates and make excellent fertilizer, and also gunpowder. Bat droppings were used to make gunpowder during the U.S. civil war. This might be why Texas is one of three US states to have a state bat - the Mexican free-tailed bat. Oklahoma also claims this species while Virginia has the Virginia big-eared bat.
10. In Britain it is illegal to kill a bat or disturb the places where they roost.