In this weeks blog it gives me great pleasure to talk to you about the colony of Egyptian Fruitbats (Rousettus aegyptiacus) here at the park and compare them to the ones we might find in our own back gardens. For me bats are such an underrated species but are so important to have in the world we live in today, playing a vital role in ecosystems around the world.
They are a diverse group of animals accounting for over 20% of the world’s mammals. There are more than 1,300 bat species in the world and they 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 up to 1.5 kilograms whilst at the other end of the scale we have the bumblebee bat, weighing only 2 grams- making it the world’s smallest mammal!
Our UK residents only eat insects, but bats elsewhere will dine on frogs, fruit, other bats, nectar from flowers, blood, pollen and fish. Echolocation is used to navigate and hunt, while others may rely on smell and vision to find food.
Found almost everywhere in the world, from the far north of Scandinavia to the deserts of the south-western USA. The only places on Earth with no bats are the Arctic, Antarctic and a few isolated Oceanic islands.
The tropics have the biggest variety of bat species; Indonesia has 175 species of bats- about ten times the number of species found in the UK while Central and South America are home to almost one third of the world’s bats species.
People have mixed emotions on bats, a bit like Marmite you could say. At the park I see this on a daily basis, some members of the public are too scared to even walk through the bats enclosure, I don’t think they realise the bats are actually behind glass. In some parts of the world bats are revered, for example in China they are considered symbols of good fortune.
Sadly in many places they are feared and misunderstood and in many countries they aren’t even protected by law despite their falling numbers. Globally, they face many pressures- even in the UK they can be affected by long bouts of cold, wet, windy weather. Such weather means there are fewer insects flying around for bats to feed on, and makes hunting more difficult. Other impacts on bat populations around the world include habitat loss, hunting, changing climate and a deadly fungus. However they do survive in some extreme environments and often have unique adaptions for hunting and roosting. We are lucky enough to have 18 species of bat in the UK, 17 of which are known to be breeding here.
Egyptian Fruit Bats
The Egyptian fruit bat is broadly distributed, inhabiting much of sub-Saharan Africa as well as northern Africa, the Middle East and Pakistan. It favours forest and grassland habitats where it can find the fruit that makes up its diet. As their name indicates they feed almost exclusively on soft fruits, such as dates, figs, apples and apricots and being a nocturnal species they fly out at night in search of this food.
The species is one of few fruit eating bats to roost in caves. In Africa colonies can include up to 9,000 bats and the Middle Eastern colonies are smaller ranging from 50-500 individuals.
At the park we have a colony of around 35 individuals, next time you’re at the park these are a definite must see as they are fascinating to watch when eating or flying. The best place to see them is when they are roosting in the top right hand side of the enclosure and if you’re lucky, hanging from one of their fruit kebabs with a mouthful of banana or, if your super lucky, watching them gracefully flying around their enclosure but blink and you’ll miss them!
Bats of Britain
Common pipistrelle (Pipistrellus pipistrellus), Soprano pipistrelle (Pipistrellus pygmaeus), Brown long eared bat (Plecotus auritus) and the Daubenton’s bat (Myotis daubentonii) are some of the common species of bats we find in Kent.
The Brown Long eared bat has huge ears which provide exceptionally sensitive hearing- they can even hear a ladybird walking on a leaf! Pipistrelles are the most common British bats, weighing around 5 grams (same as a 20p piece) and a single pipistrelle can eat 3,000 tiny insects in just one night. Known as the water bat, Daubentons fish insects from the water’s surface with their large feet or tail. All UK bats eat insects and each species has its favourite types and hunts them in its own special way. Most insects are caught and eaten in mid-air, though bats sometimes find it easier to hang up to eat larger prey. They all have very big appetites, because flying uses up lots of energy.
So why do bats matter? Like birds, some bats play a critical role in spreading the seeds of trees and other plants, they will carry seeds inside them as they digest the fruit and excrete the seeds far away from the original tree. These seeds drop to the ground in their own ready-made fertiliser, which helps them germinate and grow. Another reason is that they play an important role in many environments around the world, some plants depend partly or wholly on bats to pollinate their flowers or spread their seeds. Many people are unaware that over 500 plant species rely on bats to pollinate their flowers, including species of mango, banana, cocoa, durian, guava and agave (used to make tequila) so all you chocoholics and tequila drinkers need to be thankful for bats.
Another interesting fact for you is the process of pollination of plants by bats is called chiropterophily. In the UK, some bats are indicator species, because changes to these bat populations can indicate changes in aspects of biodiversity, they might suffer when there are problems with insect populations or when habitats are destroyed or poorly managed.
I hope my blog has helped you to discover a new found appreciation for bats and that you will visit our colony in the Bat Cave soon!