Bats of the World

White tent-making bats of Central America (Shirley Thompson)

There are more than 1,100 species of bats worldwide, making up around one-fifth of all mammals. New bat species are still being discovered but relatively little is known about many of these incredible animals. Few people realise what an essential part they play in the natural world.

Bats can be as large as a small dog or as small as a bee. The largest bats are the flying foxes with wingspans of up to 2 metres and a body weight of 1.5 kilograms. At the other end of the scale is the bumblebee bat, weighing only 2 grams – the world’s smallest mammal. Most of the world’s bats are small, similar in size to those found in the UK.

Where are bats found?

Bats are one of the most widely distributed groups of mammals. Flight has enabled them to live all over the world apart from the Arctic, the Antarctic and a few isolated oceanic islands. There are bats in the far north of Scandinavia, as well as in the deserts of the south-western USA.  Bats are most numerous in the tropics; Indonesia has 175 species of bats (over ten times the number of species found in the UK), while there are 154 in Venezuela and 137 in Mexico. Central and South America are home to almost one third of the world’s bats.

The bat family tree

Egyptian fruit bat - megabat (Mike Castle)Bats are split into two major groups, the megachiropterans (megabats) and the microchiropterans (microbats); the names are slightly misleading, as some megabats are small and some microbats are big! Megabats occur only in the Old World tropics and subtropics, but are not found in the New World of North and South America - one species (the Egyptian fruit bat) just about makes it to Europe. Microbats are found in both the Old and the New World. All UK species are microbats.

Megas vs Micros

Megabats and microbats are different in many ways. Megabats have large eyes and often dog-like faces; microbats have small eyes and often have elaborate facial structures. Microbats use echolocation to detect their prey while megabats rely on smell and vision to find food. However, the Egyptian fruit bat (pictured left), which is a megabat, also uses a form of echolocation. Megabats feed almost exclusively on fruit and flowers, while microbats have more varied tastes, eating insects, fruit, pollen, nectar, fish, frogs, other bats and blood.

Bats: Playing a vital role

Bats swarming (Hugh Clark)

Bats are vital to the health of forests. Many plants depend partly or wholly on bats for pollinating the flowers or spreading their seeds. Bats are also important in helping regrowth after forest clearance. In return, the forests are vital for the bats, providing food and roosting sites.

Chewing gum, tequila and sisal are just three products that come from plants that at least partly rely on bats for pollination or seed dispersal. Others include foodstuffs, drink, medicine, dyes, fuel, fibre and timber.

Bats under threat

Bats are threatened by disturbance to their feeding habitats or their roosts. In some areas of the world bats are revered but in many countries they are feared. Bats are creatures of the night and as such are sadly treated with suspicion and fear - in folklore bats often have a negative press. Bats also face the wrath of nature, especially on islands where they have to contend with cyclones and typhoons that can devastate their habitat.

Approximately 25% of the world's bats are threatened with extinction. Sadly at least 12 species, such as the Puerto Rican flower bat, have already become extinct.

 

The Truth about Vampire Bats

The famous Dracula novel by Bram Stoker has given bats a poor press - here are some facts about vampire bats to give the full picture.The common vampire bat (Shirley Thompson)

  • Vampire bats don’t live in Transylvania; there are three species and they all live in Central and South America.
  • Vampire bats rarely feed on human blood; they much prefer the blood of cattle, horses, pigs and birds.
  • A vampire bat doesn’t actually ‘suck’ blood, it makes a graze on its host’s skin to encourage a flow of blood and then laps this up with its tongue. 
  • Vampire bats are small. The commonest is only 7cm to 9cm long and takes approximately a tablespoon of blood each night.
  • They are caring towards members of their colony; apart from behaviour such as mutual grooming, they will even take care of others who are unable to feed by regurgitating the blood they have collected! 
  • Stroke victims may soon benefit from studies of a clot-dissolving substance in the vampires’ saliva.  

 

 

Related downloads

Bats of the World (200 KB) - 01/01/06
An introduction to the amazing variety of bats