Egyptian free-tailed bat (Tadarida aegyptiaca)

KingdomAnimalia
PhylumChordata
ClassMammalia
OrderChiroptera
FamilyMolossidae
GenusTadarida (1)
SizeTotal length: 10.4 - 12 cm (2)
Tail length: 4.1 - 4.6 cm (2)
Forearm length: 4.7 - 5.6 cm (2)
Wingspan: 30 cm (2)
Weight14 - 18 g (3)

Classified as Least Concern (LC) on the IUCN Red List (1).

The free-tailed bats are all members of the Molossidae family, a name derived from the Greek word ‘molossus’, which was used to describe a dog used by Greek shepherds in ancient times. This name refers to the bulldog-like, heavily wrinkled faces of free-tailed bats (4), while ‘free-tailed’ refers to the tail, the majority of which projects beyond the membrane that stretches between the legs of the bat, making the tail more prominent than in other families of bat (4) (5). The fine, dense fur of the Egyptian free-tailed bat is greyish-brown, turning darker on the head and back and paler on the underparts, particularly around the throat. The leathery membranes of the long, narrow and pointed wings are translucent light brown (2) (3) (4), and the rounded ears sit fairly closely together on top of the head (4).

A broadly distributed species, the range of the Egyptian free-tailed bat extends throughout Africa and the Arabian Peninsula, to India, Sri Lanka and Bangladesh (1).

This species occupies a wide range of habitats, from arid savannas to humid hills and valleys (1). Access to water plays a large part in determining where the Egyptian free-tailed bat may be found (3), not only as a source of moisture, but also because the insects on which the bat feeds tend to congregate around water pools (6). It roosts on cliff faces and in caves, as well as within man-made structures, such as old buildings and temples (1).         

Like most bats, the Egyptian free-tailed bat is nocturnal, roosting in colonies of three to hundreds or thousands of individuals during the day and flying out at night to forage (1) (6). This species flies fast at great heights for relatively long periods of time, covering large areas of open land (7). An insectivorous species, the Egyptian free-tailed bat feeds on beetles, caterpillars, flies, moths, spiders, winged termites, wasps and water beetles, which may be caught in flight or plucked from the ground (1). As well as its proficiency in flight, the Egyptian free-tailed bat is fairly adept, compared to other bat species, at moving on land. It is able tocrawl on the ground, and scamper to protection when disturbed while roosting on vertical surfaces (2).

The Egyptian free-tailed bat, and its roosting communities, is reported to have a strong odour. This may be an important factor in social interactions, and the particular smell may be an important sensory cue, aiding the bat’s return to its roost after a night foraging (8).

The female Egyptian free-tailed bat gives birth to a single young each year, typically in the summer (3), after a four-month gestation period (4).  

Insecticides, which are used to control pests such as locusts, can have a detrimental impact on bat populations, not only by directly poisoning bats but also by reducing the availability of their insect prey (1). The Egyptian free-tailed bat may also be affected by the disturbance of its roosts by humans. However, the wide range and stable population of the Egyptian free-tailed bat means that such threats do not currently pose a risk to the species’ existence (1).         

The Egyptian free-tailed bat is protected by law in some Mediterranean countries as well as in South Africa. In addition, it is likely to occur in protected areas throughout its expansive range. Further studies into the impacts of pesticides on this species have been recommended, with particular emphasis on ways in which any impacts may be reduced (1).

To find out about efforts to conserve bats around the world see:

Checked (24/08/10) by Dr Francis Gilbert, Associate Professor, University of Nottingham.
http://www.nottingham.ac.uk/~plzfg/

  1. IUCN Red List (March, 2010)
    http://www.iucnredlist.org
  2. Hoath, R. (2009) A Field Guide to the Mammals of Egypt. The American University in Cairo Press, Cairo.
  3. Apps, P. (2000) Smither’s Mammals of South Africa: A Field Guide. Struik Publishers, Cape Town.
  4. Skinner, J.D. and Chimimba, C.T. (2005) The Mammals of the Southern African Subregion. Cambridge University Press, Cambridge.
  5. Dietz, C. (2005) Illustrated Identification Key to the Bats of Egypt. Electronic Version, University of Tuebingen, Germany. Available at:
    http://www.opwall.com/Library/Egypt/Egypt%20Terrestrial/Bats/Identification%20key%20to%20the%20bats%20of%20Egypt.pdf
  6. Mills, G. and Hes, L. (1977) The Complete Book of Southern African Mammals. Struik Publishers, Cape Town.   
  7. Aardt, W.J., Bronner, G.N. and Necker, M.L. (2002) Oxygen dissociation curves of whole blood from the Egyptian free-tailed bat, Tadarida aegyptiaca E. Geoffroy, using a thin-layer optical cell: short communication. African Zoology, 37(11): 109-113.
  8. Bhatnagar, K. and Kallen, F.C. (1974) Cribriform plate of ethmoid, olfactory bulb and olfactory acuity in forty species of bats. Journal of Morphology, 142: 71-90.