Rousettus Aegyptiacus Geographic Range Habitat
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Mousetrap - Workspaces - Rousettus aegyptiacus Page 1 of 8 Rousettus aegyptiacus Class: Mammalia Geographic Range Rousettus aegyptiacus is found throughout Africa, south of the Sahara, Egypt, and the Arabian Edit Peninsula’s east and west coastlines (Grzimek, 2003). Distribution is most common along latitudes 15 degrees north through to 37 degrees south. However, Rousettus aegyptiacus has been found to inhabit latitudes as far as 40 degrees north along the southern border of Turkey. Though found predominantly in Africa south of the Sahara, Rousettus aegyptiacus has been observed on each of the Canary Islands, west of North Africa, and throughout the Gulf of Guinea, west of Middle Africa, (Nogales et al., 2006; Nowak, 1999). advanced intermediate Grzimek, 2003; Nogales, Rodriguez-Luengo, and Marrero, 2006; Nowak, 1999 Biogeographic Regions: Palearctic ( Native); Ethiopian ( Native). Other Geographic Terms: Habitat Rousettus aegyptiacus is commonly found throughout Africa’s tropical rain forests, tropical Edit deciduous forests, savanna, and Turkey’s Mediterranean scrub forests. Egyptian fruit bats have been found in arid biomes; however, they prefer to remain in habitats that provide dark, humid roosting conditions and abundant fruit tree growth (Kwiecinski and Griffiths, 1999). advanced intermediate Kwiecinski and Griffiths, 1999 Elevation: 0 to 4000 m Depth: These animals are found in the following types of habitat: Tropical; Terrestrial. Terrestrial Biomes: Desert or dune; Savanna or grassland; Forest; Rainforest; Scrub forest. Aquatic Biomes: Other: Caves. http://animaldiversity.ummz.umich.edu/workspaces/accounts/item314886691/account_vie... 4/22/2010 Mousetrap - Workspaces - Rousettus aegyptiacus Page 2 of 8 Physical Description Rousettus aegyptiacus is a medium sized bat with dorsal pelage ranging from dark brown to Edit medium gray. Ventral pelage in both genders is several shades lighter than dorsal coloration, with a collar of pale yellow or orange fur often seen around the neck. There is no color difference between genders; however, males have well-developed stiff hairs along the throat that are more recognizable than exhibited in females (Kwiecinski and Griffiths, 1999). Short fur completely covers the head almost to the end of the muzzle, with exception to the forehead where the fur is slightly longer. Ears are around the length of the muzzle, with blunt tips and dark coloration when compared to dorsal pelage. The cochlea (inner ear) is not specialized in the same way that it is found in members of Family Vespertilionidae. Egyptian fruit bats have large eyes adapted for twilight and night vision. Wing membranes are dark brown in coloration with short fur extending to the proximal half of the forearm. A claw is present on both the first and second digit, while all other fingers have cartilage. Rousettus aegyptiacus have five toes on both hind limbs, each with perforated claws (Kwiecinski and Griffiths, 1999). Males are typically larger than females with a total body length ranging from 14 to 19.2 cm, while females range from 12.1 to 16.7 cm. Adults may weigh 80 to 170 g, and have a wingspan close to 60 cm. The forearm varies between 85 to 101.9 mm in males, and 88.1 to 99 mm in females (Kwiecinski and Griffiths, 1999; Grzimek, 2003). advanced intermediate Grzimek, 2003; Kwiecinski and Griffiths, 1999 Mass: 80 to 170 g Length: 12.1 to 19.2 cm Wingspan: Approximately 60 cm (average) Basal Metabolic Rate: Some key physical features: Endothermic; Bilateral symmetry. Sexual dimorphism: Male larger. Reproduction: Mating Systems Rousettus aegyptiacus is a polygamous species, that experiences biannual breeding seasons, Edit however, instances of monoestry have been recorded in higher latitudes (Baydemir and Albayrak, 2006; Bernard and Cumming, 1997). Egyptian fruit bats observed in latitudes south of Egypt have two distinct peak breeding seasons separated by short periods in between. The first peak breeding season is from spring through summer, while the second is fall through winter. Births occur towards the end of each breeding season (Okia, 1987). advanced intermediate http://animaldiversity.ummz.umich.edu/workspaces/accounts/item314886691/account_vie... 4/22/2010 Mousetrap - Workspaces - Rousettus aegyptiacus Page 3 of 8 Baydemir and Albayrak, 2006; Bernard and Cumming, 1997; Okia, 1987 Mating systems: Polygynandrous (promiscuous). Reproduction: General Behavior Females give birth to and raises a single pup each season, though twins have been recorded Edit occasionally (Korine et al., 1994). Estimated gestation of Rousettus aegyptiacus is, 3.5- 4 months each season, with synchronized births towards the end of gestation throughout the colony (Kwiecinski and Griffiths, 1999; Okia, 1987). Newborn bats are born with deciduous teeth and are altricial - completely naked apart from a thin layer of down along the head and back. Pups are weaned at 6- 10 weeks with no differnce in growth between sexes. Young reach full adult weight and size around nine months old, about the same time young become independent from their mothers (Kwiecinski and Griffiths, 1999). Sexual maturity is reached on average at 15 months, however, females have been noted to be sexually mature at 5 - 7 months ("Egyptian Fruit Bat", 2006). advanced intermediate "Egyptian Fruit Bat", 2006; Korine, Izhaki, and Makin, 1994; Kwiecinski and Griffiths, 1999; Okia, 1987 Breeding interval: Twice yearly Breeding season: April to August and October to February Number of offspring: 1 to 2 Gestation period: 3.5 to 4 months Birth Mass: 17.9 to 22.5 g Time to weaning: 6 to 10 weeks Time to independence: 8 to 9 months Age at sexual or reproductive maturity (female): 5 to 16 months Age at sexual or reproductive maturity (male): 14 to 18 months Key reproductive features: Seasonal breeding; Gonochoric/gonochoristic/dioecious (sexes separate); Sexual; Viviparous. Reproduction: Parental Investment After birth Rousettus aegyptiacus pups are cared for solely by their mothers for around nine Edit months. They are capable of flying at 63 - 70 days after birth and will continue to stay with their mother until they have reached, adult weight and size. Once mature, males will leave maternity colony to join bachelor groups, and females will join a maternity colony (Kwiecinski and Griffiths, 1999). advanced intermediate http://animaldiversity.ummz.umich.edu/workspaces/accounts/item314886691/account_vie... 4/22/2010 Mousetrap - Workspaces - Rousettus aegyptiacus Page 4 of 8 Kwiecinski and Griffiths, 1999 Parental investment: Altricial; Female parental care. Lifespan/Longevity The lifespan of Rousettus aegyptiacus is 22 years on average with a maximum of 25 years in Edit captivity for both males and females. In wild populations average lifespan is typically 8 - 10 years due to factors such as predation, vitamin D deficiency, calcium-phosphorus imbalance, and osteoproliferation. Longevity in captive bats is also dependent on environmental temperatures, and neurological impairment (Kwiecinski and Griffiths, 1999). advanced intermediate Kwiecinski and Griffiths, 1999 Longest known lifespan in wild: less than a year years (min) Longest known lifespan in captivity: 25 years (max) Expected lifespan in wild: 8 to 10 years Expected lifespan in captivity: 25 years (max) Behavior Rousettus aegyptiacus is found in groups of various sizes ranging from small colonies of 20 to 40 Edit members to large colonies of 9,000. These colonies prefer to roost during the day in dark, slightly humid environments such as cave systems and ruins, though small colonies have been seen roosting in trees (Grzimek, 2003). During the breeding seasons males and females separate; males forming bachelor groups and females forming maternity colonies. Egyptian fruit bats roost in close contact with other members of the colony to reduce the influence of temperature fluctuations. Close contact among members of the colony also allows communication with each other throughout the day during roosting. Egyptian fruit bats are more active during the late afternoon, into the night when grooming is more frequent (Kwiecinski and Griffiths, 1999). Rousettus aegyptiacus leave the day roost close to sunset each evening to forage, and return before sunrise. During the summer months the more prolonged intensity of light delays the emergence of Rousettus aegyptiacus from the roost, suggesting a circadian rhythm synchronized to light-dark cycles. Due to the change in light intensity, Rousettus aegyptiacus have different patterns of activity between the summer and winter seasons. Summer seasons experience longer feeding intervals then winter seasons, despite reduced dark periods and delayed roost emergence (Kwiecinski and Griffiths, 1999). advanced intermediate Grzimek, 2003; Kwiecinski and Griffiths, 1999 Home Range http://animaldiversity.ummz.umich.edu/workspaces/accounts/item314886691/account_vie... 4/22/2010 Mousetrap - Workspaces - Rousettus aegyptiacus Page 5 of 8 Home range varies in Rousettus aegyptiacus. This species has been noted to migrate southward in the northern regions of their geographic range, and forage great distances away from the day-roost. Males appear to have defendable territories, however, no defined sizes have been observed (Kwiecinski and Griffiths, 1999). advanced intermediate Kwiecinski and Griffiths, 1999 Territory Size: Key behaviors: troglophilic; flies; nocturnal; motile; colonial. Communication and Perception Rousettus aegyptiacus is one of only three members of the Rousettus genus to use both visual Edit