Egyptian slit nose
| Egyptian slit nose | ||||||||||||
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Egyptian slit nose ( Nycteris thebaica ) |
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| Scientific name | ||||||||||||
| Nycteris thebaica | ||||||||||||
| ( Geoffroy , 1813) |
The Egyptian slit- nosed bat ( Nycteris thebaica ), also known as the Egyptian slit-nosed bat , is a species of bat from the slit-nosed family that is native to Africa. The species name refers to the city of Thebes near Luxor in Egypt , where the species was first described by the naturalist Étienne Geoffroy Saint-Hilaire .
description
The Egyptian slit nose has large, oval ears and an eponymous, deep slot in the muzzle, which lies between two small nostrils . The tragus is shaped like an upside-down pear. The tail is enclosed in the tail flight membrane and, like other members of this family, ends in a T-shaped cartilage that supports the tail flight membrane. The fur is generally lighter than that of other slit noses, varying between dusty gray and a reddish brown. The belly is light gray to white. The color of the coat does not vary geographically, but it has been observed that individuals from drier areas are generally lighter. The forearm length is 39.2–47.4 mm, the wingspan just under 30 cm. Males weigh on average 8.7 g, the weight of females is 9.8 g.
Way of life
nutrition
The Egyptian slit nose has relatively large, wide wings, which makes it an agile pilot. Like most bats, it is nocturnal and feeds on arthropods . The species is relatively opportunistic. The prey is either caught in flight or picked up from leaves and soil. In addition to echolocation calls , the Egyptian slashed nose also uses sounds produced by the prey, such as crawling on loose leaves. Preferred prey animals include grasshoppers , butterflies and beetles . During the dry season, the caterpillars of butterflies play a more important role in the diet of the Egyptian rascal. In addition, the choice of prey depends on the respective occurrence in the distribution area, habitat and season. It is assumed that it belongs to the species of migratory bat that have to accept long migratory movements in order to find suitable food.
Calls
The echolocation calls of the Egyptian slit nose are short (<2 ms), multi-harmonic and of low intensity. As the bat approaches prey, the call rate increases. The calls begin in the frequency range of 97 kHz and then decrease to the range around 61 kHz. They are therefore not audible to the human ear. In addition to echolocation, the Egyptian slit nose produces two types of calls that can also be heard by humans with a duration of> 40 ms. One of them is in the range between 8.8 and 12.6 kHz and is mainly used in the colonies. The second call starts at 22.1 kHz, drops to 10.1 kHz and then rises again to the starting frequency. This call is produced by the bats when they leave the hanging place.
Social behavior
During the day, the Egyptian slit nose can be found in artificial structures such as mines, tunnels, bunkers, ruins, wells and tombs, but also in natural hanging places such as caves, hollow trees, crevices, as well as in aardvark structures and in termite mounds . Egyptian rascals often form colonies of several thousand individuals. In South Africa you can often find the kind in caves along with other bats as Myotis tricolor , the ordinary circular leaf-nosed ( Hipposideros caffer ) Rhinolophus simulator , R. clivosus that Blasius's horseshoe bat ( Rhinolophus blasii ) and long wing bat (genus Miniopterus ). In the Democratic Republic of Congo , the Egyptian slit-faced bat also divides the hanging place occasionally with Rhinolophus swinnyi , in East Africa with the Egyptian fruit bat ( Rousettus aegyptiacus ) and Taphozous perforatus in Malawi with Rhinolophus fumigatus in Senegal with the United ear slit nose ( Nycteris macrotis ) and in Egypt with Asellia tridens .
Reproduction
Egyptian rascal noses can become pregnant several times a year in tropical areas, while populations in the subtropics and in areas with temperate climates are monoestrous. The females give birth to a single young each after a gestation period of around 5 months in temperate areas and 2.5 to 3 months in tropical areas. Newborns weigh an average of 6.0 g and are taken along by the females hanging on their teats during the foraging flights.
distribution and habitat
The Egyptian slit nose occurs in large parts of Africa , the Arabian Peninsula and in Israel . They are found in a variety of habitats, such as savannahs , woodlands, and rainforests . The species is classified as harmless by the IUCN .
literature
- Gray PA, Brock-Fenton M., Van Cakenberghe V. (1999): Nycteris thebaica . In: Mammalian Species , No. 612, pp. 1-8
