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The Gambian epauletted fruit bat (''Epomophorus gambianus'') is a species of megabat in the Pteropodidae family. The species is known to travel in packs and are also known to be tropical. It is found in Benin, Burkina Faso, Cameroon, Central African Republic, Chad, Democratic Republic of the Congo, Ivory Coast, Ethiopia, Gambia, Ghana, Guinea, Guinea-Bissau, Liberia, Mali, Niger, Nigeria, Senegal, Sierra Leone, Sudan, and Togo. Its natural habitats are subtropical or tropical dry forests, dry savanna, and moist savanna. It is threatened by habitat loss. Populations of epauletted fruit bats are threatened by pesticides on fruit, human disturbance and over-collecting in the past. However the number one reason it may be threatened is habitat destruction. Mostly found in Africa, these creatures have grayish-brown color fur with a white patch at the base of their ear in both males and females. These fruit bats are also very noisy creatures. In the context of mating behavior (see "Reproduction" below), adult males may hang from perches and perform a calling-display during which they utter a moderately loud bell like 'ping' at intervals of 1–3 seconds.(Kingdon) It is very easy to tell the male fruit bat from the female fruit bat. In comparison, the males are usually larger than the females. The males also have gland-like pouches in the skin of their shoulder, that is surrounded by light colored patches and/or tufts of fur. Thus, one of the reasons why they are named Gambian epauletted fruit bats, it produces the effect of epaulettes; a decorative or ornamental piece. The only way one would be able to see the epaulettes is when the male becomes stressed or sexually stimulated. Both males and females have small rounded ears, with a dog-like muzzle. (Neuweiler) Their head and body length are usually 125–250 mm and their wing span is about 508 mm for the males. This creature also has a tail that is hard to detect beneath the inter femoral membrane. Both male and female Gambian epauletted fruit bats are about the length of a forearm, 60–100 mm. The species is known to hang off of evergreen trees during the day alone or spread out from one another and travel in packs of hundreds during the late hours of the night in the forest of Africa. == Behavior == The Gambian epauletted fruit bats are frugivorous and will appear wherever fig, mango, guava or banana trees are in fruit. The social behavior within fruit-bat camps does not stop at individual family groups. The whole colony is organized, with separate peripheral groups of immatures and non-breeding adults. The epauletted fruit bats travel in small groups of six to twenty bats. When the fruit bats are in flight, they remain together in long processions. The leaders often change, yet they retain the same direction of flight(Mickleburgh). They frequently sniff at each other’s scent glands to establish personal recognition. Which represents high levels of social organization. When one is shot down, they show great concern and gather round swooping low to inspect it; a sign of affinity rather than totally independent behaviour. They roost during the day in mango trees and bamboo reeds or other trees. The Gambian epauletted fruit bats hang upside down alone or in groups up to twenty. The species' droppings support whole ecosystems of unique organisms, including bacteria useful in detoxifying wastes, and producing gasohol. This species feeds on nectar and fruits of many West African trees, presumably acting as pollinator and/or seed disperser. Some flowering trees depend on the bats for pollination(Fenton). The pack move during sunset in large flocks from resting areas to feeding areas. To avoid predators, the bats will carry fruit away from the tree before eating. Over several nights bats may carry more than a ton of seeds from a single wild fig tree, dramatically increasing the number of seedlings that will survive in new locations. The fruit bats spend over half their lives roosting in various places(Wilson). On the outskirts of the camp non-territorial males act as guards. They are alert to the slightest disturbance. They perform a visual inspection and either give a loud alarm signal, or remain still, keeping an eye open (Nowalk). The Gambian epauletted fruit bats are unlike other bats because they use sight rather than echolocation to find food. They also rely heavily on their smell because they use it to locate food and establish bonds with one another(Nowalk). 抄文引用元・出典: フリー百科事典『 ウィキペディア（Wikipedia）』 ■ウィキペディアで「Gambian epauletted fruit bat」の詳細全文を読む スポンサード リンク
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