Epomophorus gambianus (Ogilby, 1835)

Don E. Wilson & Russell A. Mittermeier, 2019, Pteropodidae, Handbook of the Mammals of the World – Volume 9 Bats, Barcelona: Lynx Edicions, pp. 16-162 : 96-97

62.

Gambian Epauletted Fruit Bat

Epomophorus gambianus

French: Epomophore de Gambie / German: Gambia-Epaulettenflughund / Spanish: Epomdforo de Gambia

Taxonomy. Pteropus gambianus Ogilby, 1835 ,

“ Gambia.” Restricted by D. Kock and colleagues in 2002 to “ Banjul,” Gambia.

Epomophorus gambianus is in the gambianus species group, and E. reii is a synonym. Taxonomic status of larger subspecies pousarguesi needs further investigation because it is known from just four specimens recorded in two close localities. Former subspecies crypturusis recognized here as a related but distinct species. Two subspecies recognized.

Subspecies and Distribution.

E.g.gambianus Ogilby,1835—Senegal to Ethiopia, excluding partof Central African Republic.

E. g. pousarguesi Trouessart, 1904 — Central African Republic (4° N, 18-19° E).

Descriptive notes. Head—body 108-170 mm (males) and 130-162 mm (females), tail 0-6 mm (males) and 0-8 mm (females), ear 21-27 mm (males) and 19-28 mm (females), hindfoot 20-27 mm, forearm 80— 100 mm (males) and 75-95 mm (females); weight 96-155 g (males) and 87-145 g (females). Males are on average larger than females. Adult males have white epaulettes and dark brown necks and chest. Head is flat, muzzle is very long and narrow, deep incision occurs between nostrils, and lips are greatly expansible. Eyes are large; irises are chestnut-brown. Ears are relatively short, rounded, and brown with dark rims, with anterior and posterior light ear patches. Tongue is relatively long. Dorsum is pale fawnbrown, paler on shoulders and with yellow tinges on head, neck, and rump; some males are darker (sepia-brown), others are much paler; hairs are dark brown at bases; pelage is soft, slightly fluffy, and mid-dorsally c¢. 10 mm, extending along forearm dorsally and ventrally. Venteris slightly to markedly paler than dorsum; males sometimes have pale or white ventral patch. Wings have claw on second digits; membranes are brown and attach to second toes. Skull is long and narrow, especially in males; braincase is flat and slopes downward posteriorly; sagittal crest is weak; lambdoid crests and supraorbital processes are well developed; post-dental palate is extremely concave; and zygomatic width is relatively narrow. There are six thick palatal ridges, of which two are post-dental; fourth is midway between third and fifth; and ridges 2-4 are undivided. Dental formula for all species of Epomophorusis 12/2, G1/1,P 2/3, M 1/2 (x2) = 28. Supernumerary teeth (e.g. premolars) can be present. C' and first upper premolar (P?) recurved and pointed, lower cheekteeth not lobed, and P, almost caniniform.

Habitat. Primarily Sudan and Guinea savannas ( Isoberlinia , Fabaceae , woodland in West Africa) and fringes of Northern Rainforest-Savanna Mosaic biotic zones, sometimes cleared areas in lowland rainforests and mangrove forests, from sea level up to elevations of ¢. 2900 m.

Food and Feeding. The Gambian Epauletted Fruit Bat feeds opportunistically on soft endemic and cultivated fruits and nectar. Its feeds alone but sometimes in mixed-species groups with Lesser Epauletted Fruit Bats ( E. pusillus ) and Veldkamp’s Epauletted Fruit Bat ( Nanonycteris veldkampii ). It is an important seed disperser and contributes to regeneration of abandoned farmlands. It feeds on various fruits, particularly figs ( Ficus , Moraceae ) and many introduced species, and heavily uses nectar of species of Malvaceae ( Adansonia , Bombax , and Ceiba ), Fabaceae (Parkia) , and Bignoniaceae (Kigelia) .

Breeding. In Ivory Coast, reproductive cycle is continuous polyestry, with postpartum estrus. Calling displays of males probably attract females for mating. Gestation lasts 5-6 months. Littersize is generally one; there are two litters/year: beginning of wet season (April) and end of wet season (October).

Activity patterns. During the day, Gambian Epauletted Fruit Bats roost in foliage; they remain silent and hardly move, except for grooming. At dusk, adult males start performing calling displays during which they generate bell-like “ping” sounds every 1-3 seconds, display their epaulettes, and beat their wings between calls; displays can last to up to 35 minutes. Roosts are then left (18:40-19:00 h), either by individuals or groups that return at 04:45-05:15 h. During the night, calling displays can be repeated at othersites. Gambian Epauletted Fruit Bats fly low over rivers to drink directly, or they lick water from wet pelage.

Movements, Home range and Social organization. The Gambian Epauletted Fruit Bat roosts alone or in groups of more than 100 individuals hanging from small branches in the shade, generally in canopies of the highest savanna trees, including Khaya senegalensis and Azadirachta indica (both Meliaceae ); Kigelia africana (Bignoniaceae) ; Mangifera sp. (Anacardiaceae) ; Cola sp. (Malvaceae) ; and Ficus sp. (Moraceae) . It hangs at least 30 cm from each other and barely contact one another. In some regions,itis nomadic in response to seasonal changes in food availability. Based on isotope data, the Gambian Epauletted Fruit Bat has been suggested to have an east-west migratory pattern, which is even more pronounced than migration displayed by the African Straw-colored Fruit Bat ( Eidolon helvum ). Six specimens that were captured in February in Mali most probably originated 3000 km to the east.

Status and Conservation. Classified as Least Concern on The IUCN Red List. The Gambian Epauletted Fruit Bat has a wide distribution and large population.It is probably not declining fast enough to be assigned to a higher category. Major threats are probably hunting and habitat loss due to changing land use and climate change.

Bibliography. Boulay & Robbins (1989), Happold, D.C.D. & Happold (1978), Happold, M. (2013c), Kock et al. (2002), Lanza et al. (2008), Nesi et al. (2011), Omatsu et al. (2008), Peterson & Nagorsen (1975), Tanshi & Fahr (2016).

Figures

50. Western Woermann’s Fruit Bat (Megaloglossus azagnyi), 51. Eastern Woermann’s Fruit Bat (Megaloglossus woermanni), 52. Angolan Soft-furred Fruit Bat (Lissonycteris angolensis), 53. Little Collared Fruit Bat (Myonycteris torquata), 54. Sao Tome Collared Fruit Bat (Myonycteris brachycephala), 55. Sierra Leone Collared Fruit Bat (Myonycteris leptodon), 56. Bergmans’s Collared Fruit Bat (Myonycteris relicta), 57. Broad-faced Fruit Bat (Plerotes anchietae), 58. Hammer-headed Fruit Bat (Hypsignathus monstrosus), 59. Franquet’s Epauletted Fruit Bat (Epomops franqueti), 60. Buttikofer’s Epauletted Fruit Bat (Epomops buettikoferi), 61. Veldkamp’s Epauletted Fruit Bat (Nanonycteris veldkampr), 62. Gambian Epauletted Fruit Bat (Epomophorus gambianus), 63. Peters’s Epauletted Fruit Bat (Epomophorus erypturus), 64. Angolan Epauletted Fruit Bat (Epomophorus angolensis), 65. Little Epauletted Fruit Bat (Epomophorus labiatus), 66. Minor Epauletted Fruit Bat (Epomophorus minor), 67. Ansell’s Epauletted Fruit Bat (Epomophorus anselli), 68. Wahlberg's Epauletted Fruit Bat (Epomophorus wahlbergi), 69. Dobson’s Epauletted Fruit Bat (Epomophorus dobsonu), 70. Sanborn’s Epauletted Fruit Bat (Epomophorus grands), 71. Lesser Epauletted Fruit Bat (Epomophorus pusillus), 72. Hayman’s Epauletted Fruit Bat (Epomophorus intermedius)

E.g.gambianus Ogilby,1835—Senegal to Ethiopia, excluding partof Central African Republic. E. g. pousarguesi Trouessart, 1904 — Central African Republic (4° N, 18-19° E).