Seychelles sheath-tailed bat facts for kids
Quick facts for kids Seychelles sheath-tailed bat |
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| A dead Seychelles sheath-tailed bat collected for research | |
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Coleura
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| Species: |
seychellensis
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| Seychelles sheath-tailed bat range | |
The Seychelles sheath-tailed bat (Coleura seychellensis) is a special type of sac-winged bat. It lives on the central granite islands of the Seychelles, which are islands in the Indian Ocean. These bats are active at night, hunting insects. They like to rest together in caves during the day.
This bat used to be very common across the islands. However, its home has shrunk a lot. Because of this, the International Union for Conservation of Nature says this bat is critically endangered. This means it is very close to disappearing forever. The main reasons for this are new buildings and roads, and new plants and animals brought to the islands that cause problems for the bats.
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Life and Habits of the Bat
Seychelles sheath-tailed bats are quite small, weighing about 10 to 11 grams. That's about as much as a few paperclips! These bats usually live in caves or old houses, hiding in small cracks and spaces.
Long ago, people saw these bats flying around bamboo plants at sunset. During the day, they would rest in cracks on mountainsides that faced the sea. These hiding spots were often covered by large palm leaves.
These bats are insectivores, meaning they eat only insects. They mostly eat tiny flies that live near marshes. Sometimes, if their usual feeding spots are gone, they might hunt in other places like palm forests. Bat families often live in groups, with one male bat and several females.
Scientists have studied these bats a lot recently. They found that the bats like to feed in small clearings within forests, where they can find many different kinds of insects. Even though these bats can have many babies and eat different insects, they are very sensitive to changes in their environment. They need several safe places to rest in healthy areas.
Why This Bat Needs Help
In the past, the Seychelles sheath-tailed bat was probably found all over the Seychelles islands. But its numbers have dropped a lot, and it has disappeared from most islands. The International Union for Conservation of Nature now lists this bat as critically endangered. In 2013, a group called Bat Conservation International put this bat on its list of 35 most important species to save worldwide.
This bat is one of the most endangered animals on Earth. Scientists believe fewer than 100 of them are left! Their homes have been damaged by farms growing coconuts and by a plant called kudzu vine. These changes have reduced the scrubland and the number of insects the bats can eat.
The biggest group of these bats lives on Silhouette Island. Smaller groups can also be found on Mahé, Praslin, and La Digue islands. These bats can live for about 20 years. They are about 55 to 65 millimeters long. Male bats sometimes fight each other to find a mate.
How Bats "See" with Sound
Bats use something called echolocation to find their way around and hunt. It's like they use sound to create a picture of their surroundings. Here's how it works:
1. A bat makes a sound, like a high-pitched squeak. 2. These sound waves travel out and bounce off objects, like a tree or a flying insect. 3. The echoes (the bounced-back sounds) then return to the bat's super-sensitive ears.
By listening to how the echoes come back, the bat can figure out where objects are, how big they are, and even how fast they are moving. This helps them fly in the dark and catch tiny insects.
Bats can change their calls. For example, when they get closer to an insect they want to catch, they make their calls faster. This helps them get a more detailed "picture" of their prey.
Over many years, bats have changed a lot to become experts at echolocation. Their inner ears are specially designed to hear these echoes very well. This amazing ability helps them survive and thrive in the dark.
Bat Talk: Vocalizations
Within echolocation, bats also use different types of calls for different reasons. Think of it like different words or phrases they use. Scientists have described four main types of calls for bats in this family:
- Broadband FM calls: These are like a quick "sweep" of sound.
- Narrowband FM calls: These start with a sweep and then have a more focused, narrow sound at the end.
- Long multi-harmonic calls: These have several different sound parts in a short time.
- Short multi-harmonic calls: Similar to the long ones, but even shorter.
Bats can change how fast, loud, or quiet their calls are. They do this depending on what they are doing. For example, they might use different calls when they are hunting, navigating, talking to other bats, protecting their space, or trying to find a mate.
Scientists have studied a bat called the Saccopteryx bilineata, which is in the same family as the Seychelles sheath-tailed bat. This bat uses many different "syllables" in its calls. They even have seven main types of vocalizations, including:
- Pulses: Short, steady calls.
- Barks: Similar to pulses but longer, often made by males.
- Chatter: Fast sequences of calls.
- Whistles: Very loud calls made by males to females.
- Screeches: Calls related to arguments over territory, made by both males and females.
- Territorial songs: Complex songs used to mark their space.
- Courtship songs: Special songs males use to attract females. These songs are so high-pitched that humans can't hear them!
While we don't know as much about the specific calls of the Seychelles sheath-tailed bat, scientists have identified four types of calls for them:
- Complex social calls: Used to talk to other bats.
- Orientation calls: Used to find their way in tight spaces.
- Orientation calls in open areas: Used for navigation in open spaces.
- Foraging calls: Used when hunting for food.
Generally, the Seychelles sheath-tailed bat uses lower-pitched sounds to navigate and higher-pitched sounds to find prey, especially when there are many objects around them.
