Yellow-winged bat
| Yellow-winged bat | |
|---|---|
 |
|
| Conservation status | |
| Scientific classification | |
| Kingdom: | Animalia |
| Phylum: | Chordata |
| Class: | Mammalia |
| Order: | Chiroptera |
| Family: | Megadermatidae |
| Genus: | Lavia |
| Species: | L. frons |
| Binomial name | |
| Lavia frons (É. Geoffroy, 1810) |
|
 |
|
| Yellow-winged Bat range | |
The Yellow-winged bat (Lavia frons) is one of five species of false vampire bat (family Megadermatidae) from Africa.
Contents |
[edit] Description
The yellow-winged bat has a total length of 58-80 mm[1] and a body weight of 28-36 g.[2] Females tend to be slightly larger than males. The wingspan averages 36 cm.[3] This species has a long pelage that is pearl grey or slaty gray, often greenish-yellow posteriorly in males and on the underparts.[4] As its name suggests, the bat has wings that are reddish-yellow which is also the color of its other membranes as well as its noseleaf and ears. The membranes are largely hairless although fur exists sparsely on the upper arms.[4] The ears are fairly long and contain a divided tragus that is relatively spiky.[3] The noseleaf is long and broad with a bluntly truncated tip.[4] The eyes are also relativity large. Although the yellow-winged bat has a well developed interfemoral membrane, it lacks an external tail. The dental formula is 
.
The bat has a well-developed frontal expansion of the skull with prominent postorbital processes.[4] Male bats have glands on the lower back that excretes a yellowish substance which discolors the area around it and may give males their sweet, spicy smell.[1] Females have false nipples near the anus which are used by the young to hold on to.[5]
[edit] Ecology
The yellow-winged bat has a extensive range throughout the middle of Africa. It is found in Benin, Burkina Faso, Burundi, Cameroon, Central African Republic, Chad, Democratic Republic of the Congo, Ivory Coast, Eritrea, Ethiopia, Gabon, Gambia, Ghana, Guinea-Bissau, Kenya, Malawi, Mali, Niger, Nigeria, Rwanda, Senegal, Sierra Leone, Somalia, South Sudan, Sudan, Tanzania, Togo, Uganda, and Zambia. The bat mostly lives in riparian habitats in low-lying woodland and savannah in elevations of less than 2,000m.[4] It can be found in forest or open habitat, particularly in low braches of acacia tree and thorn bushes along rivers, swamps and lakes.[6] This bat tends to fly close to and over rivers and open water.[7] It prefer to live in areas were the vegetation is not very dense, where it can have a greater view of its surroundings.[6] The yellow-winged bat primarily roosts in small trees and shrubs.[7] It can also be found roosting in trees cavities and buildings.[1] Bats use primary and peripheral roost trees. The primary roost tree is where bats return in the morning and meet before foraging in the evening.[8] Bats make short flights between primary and peripheral roost trees. These flight s are frequent on hot days, possibly because the bats are looking for shade. Long flight are less common and are more often made in the heat of midday.[8]
Unlike other false vampire bats, the yellow-winged bat feeds only on insects and not small vertebrates. It will feed on both soft- and hard-bodied insects.[2][8] Bats have been recorded feeding on termites, scarab beetles, orthopterans, lepidopterans and dipterans.[2][8] The size of prey ranges from very small to relatively large.[2] The yellow-winged bat is a sit-and-wait predator that hangs from low branches and listens for prey on the ground. It then approaches and attacks the prey in short flights. It is possible that the bat has an exclusive feeding niche, since it has a unique foraging style and the time and place of foraging does not overlap with other bats in the area.[8] This species likely has high predation pressure due to its coloration, roosting habits and activity during both day and night.[4] Nevertheless, the bat is alert during the day. Predators include mambas, bat hawks, night tree vipers and common kestrels.[4]
[edit] Behavior and life history
The yellow-winged bat is a behaviorally monogamous species. Pairs of males and females are formed and maintained during the breeding season and each pair maintains exclusive foraging territories.[8] The male and female of a pair roost less than 1 m apart. One member is vigilant during the day and will turn its head 225° and pin its ears to the back to check for disturbances. Between the foraging periods in the morning and evening, the male visits the peripheral roost and defends it from conspecifics.[8] In the morning, one member of the pair will swoop up to its partner and hover, with or without hovering. The pair then separates for the day. The male and female meet again at the primary roost tree before the evening foraging and will groom and stretching and perform other social interaction.[8] The maximum amount of male-female social interaction occurs between May and early June. This is when the rains are abundant, insects are plentiful and the young learn how to forage.[5] Male and females will interact at midday, dusk and dawn. There are also apparently courtship flights during this time and male attempt to mount perched females.[4]
The exact time in which the yellow-winged bat reproduces, can vary by region. It gives birth at the end of the dry season in October in Zambia, while at Lake Baringo in Kenya, it typically gives birth at the beginning of the so-called long rains in April, which extend until June.[4] The gestation period lasts around 3 months[2] with a single young being born. For the first several weeks, the young clings tightly to its mother even during foraging.[5] Soon, the young is left at the roost for around a week and begins to fly alone.[4] The young practices flying by flapping its wings while clinging its feet to its mother’s neck.[5] Newly Volant young will forage with their and soon develop a foraging performance that closely resembles that of their parents. Young are weaned 20 day after their first solo flight. Until around 50 days after its first flight, a young will live in its parent’s territory, synchronize its grooming and foraging periods with them and periodically huddle against its mother when roosting.[5]
The yellow-winged bat emits search-phase echolocation calls and at least three social calls that can be heard by humans.[4] The echolocation calls is a short, low-intensity broadband calls that give the bat information on close objects.[8] The three main types of social calls are made before or during aggression, copulation or interactions between mothers and offspring.[4]
[edit] Status
Little is known about human dynamics on the population dynamics of the yellow-winged bat and there is no record of population change over time.[4] It is not listed as threatened or endangered by any national or international organization. However, it is likely uncommon.[4]
[edit] References
- ^ a b c Rosevear, D. 1965. The Bats of West Africa. London: Trustees of the British Museum.
- ^ a b c d e Kingdon, J. 1974. East African Mammals: An Atlas of Evolution in Africa, Volume 2, Part A: Insectivores and Bats. London: Academic Press.
- ^ a b Lavia frons Yellow-winged bat Animal Diversity.
- ^ a b c d e f g h i j k l m n Vonhof, M., M. Kalcounis. 1999. "Lavia frons". Mammalian Species, No. 614: 1-4.
- ^ a b c d e Vaughan, T., R. Vaughan. 1987. "Parental Behavior in the African Yellow-Winged Bat". Journal of Mammalogy, 68: 217-223.
- ^ a b Nowak, R. M. 1994. Walker’s bats of the bats of the world. John Hopkins University Press.
- ^ a b Happold, D. C. D. 1987. The mammals of Nigeria. Clarendon Press, Oxford.
- ^ a b c d e f g h i Vaughan, T., R. Vaughan. 1986. "Seasonality and the Behavior of the African Yellow-Winged Bat". Journal of Mammalogy, 67: 91-102.
- D.E. Wilson & D.M. Reeder, 2005: Mammal Species of the World: A Taxonomic and Geographic Reference. Third Edition. The Johns Hopkins University Press, Baltimore
- Mickleburgh, S., Hutson, A. & Bergmans, W. 2004. Lavia frons. 2006 IUCN Red List of Threatened Species. Downloaded on 30 July 2007.
|
|||||||||||||||||
