Bats
How many visitors to EKZNW parks realise that they are surrounded by fascinating animals that represent a quarter of the world’s mammal species but are rarely seen, and even more rarely feature on the park’s species list?
Bats are among the most misunderstood and feared animals on the planet, they are surrounded by a tissue of untrue myths and folkloric beliefs. Bats do not get caught in your hair, stick to your skin, chew your toes, cause strokes, or suck blood and no bat is blind, they are very clean little animals, all have eyes and can see much better than we can at night. Fruit bats can even see colour at night.
In South Africa we have 56 of the world’s 1,011 bat species, 27 species can be found in KZN and three of our KZN bats, the Trident bat, the Large-eared free-tailed bat and Rendall’s serotine are specially protected on the same schedule as the Black Rhino.
Bats live a very precarious existence, most bats have just one pup a year and 70% of those pups do not make it to adulthood. It is a very difficult in the space of a few weeks to grow to your mother’s size, learn to fly and hunt and catch enough food to grow strong enough to weather your first lean winter months. Bats that do get through their first year go on to live incredibly long lives for such small animals; bats have been recaptured as long as 37 years after first being banded.
Insectivorous bats are the main predator of night flying insects, each bat must eat up to a third of its body weight a night, that in the case of a little free-tailed bat means around 4 grams of insects or about 2,000 mosquito sized insects every night. Large colonies of bats consume literally tons of insects in a year. Studies are showing that close proximity to bat roosts can save farmers thousands of Rands a year as the bats predate on crop pests. Even fruit bats, long persecuted by our fruit farmers, have been shown to be beneficial to the farmer and not a pest. Farmers pick fruit before it ripens so as to get it to market in good condition, fruit bats will only eat ripe fruit so they clean up the orchards, eating fruit that has been missed by the pickers and thus removing the breeding ground of fruit flies. Many enlightened farmers are now reinstating bat habitat or putting up bat boxes to attract bats back to their farms.
Fruit bats are vital to our planet, they are the propagators of 95% of rain forest tree species, and without rain forests our planet would be as desolate as Mars or the moon. Birds sit in a tree and eat the fruit, dropping the seed to the dark forest floor below where no sun penetrates to allow germination, only fruit bats take seed away from the parent tree and either spit it out or defecate it as they fly over open cleared areas. Fruit bat propagation can be seen at work in the Greater St Lucia Wetland Park, the majority of tree species that are rapidly re-colonising the cleared commercial forestry areas are Figs, Marula, Yellow-wood, Milkwoods etc., whose seeds have been carried to the cleared areas by the Wahlberg’s epauletted and Egyptian fruit bats that live in the park.
The tree of Africa, the mighty Baobab, is only pollinated by fruit bats, without the bats Baobab trees would die out, causing a linked extinction of many other fauna species that depend on the Baobab for food and shelter.
Bats are incredibly intelligent animals, for its size our 6 gram Banana bat has the greatest brain surface area of any mammal, including humans. The insectivorous Banana bat lives in the unfurling centre leaf of banana trees, as the leaf uncurls it no longer shelters the bats so the whole colony moves home every few days, how they communicate where they will all move to, and who makes the decision is not yet known. Scientists working with Mexican free-tailed bats in Texas, USA have discovered that the bats use true language; the bats use syntax to combine sounds into sentences that have different meanings. The work is continuing but already the meaning of more than twenty simple bat sentences has been identified.
TSadly due to widespread and indiscriminate use of insecticides coupled with habitat loss bats are dying at a greater rate than they can reproduce. It is estimated that 75% of Europe’s bats have been lost in the past 20 years. Bats and their roosts are now vigorously protected in Europe with stiff penalties for interfering with them. In urban and farming areas South African bat numbers are also reducing at an alarming rate, three bat species feature in South Africa’s top ten most endangered species list. Our bats are protected by the Wildlife and Pesticides acts and theoretically heavy fines can be imposed for killing bats, sadly though it is almost impossible to interest the authorities in prosecuting anyone who deliberately kills bats.
The Bat Interest Group of KZN is a voluntary organisation that seeks to protect our bats by educating the public about bats and their essential place in our environment, contact batskzn@telkomsa.net for more information. For those wanting to learn more about our bats, Bats of Southern Africa by Peter John Taylor, published by the University of Natal Press is available from good bookstores or online from the UKZN Press website http://www.unpress.co.za/
