Pteropus samoensis, Peale, 1848

Don E. Wilson & Russell A. Mittermeier, 2019, Pteropodidae, Handbook of the Mammals of the World – Volume 9 Bats, Barcelona: Lynx Edicions, pp. 16-162 : 150

164.

Common Samoan Flying Fox

Pteropus samoensis

French: Roussette des Samoa / German: Gewohnlicher Samoa-Flughund / Spanish: Zorro volador de Samoa

Other common names: Samoan Flying Fox

Taxonomy. Pteropus samoensis Peale, 1848 ,

Tutuila Island ( American Samoa), Samoan Islands.

K. Andersen in 1912 suspected a closerrelationship between samoensis and anetianus and placed both in the samoensis species group. According to genetic studies by F. C. Almeida and colleagues in 2014, this group represents a second radiation of the genus Pteropus in the Pacific region, which includes at least six additional species: fundatus , tuberculatus , nitendiensis , rayneri , cognatus , and rennelli . S. M. Tsang in 2015 also added capistratus and vetula in the samoensis group. Taxon nawaiensis was considered as a full species by Andersen in 1912 but was treated as a subspecies of samoensis by K. Wodzicki and H. Felten in 1975. Genetic data provided by A. L. Russell and others in 2016 identify P. samoensis as monophyletic with respect to other Pteropus and internally composed of two groups that correspond exactly to nawaiensis and samoensis . Two subspecies recognized.

Subspecies and Distribution.

P.s.samoensisPeale,1848—WesternSamoa(SavaiiandUpoluIs)andAmericanSamoa(Tutuila,Ofu,Olosega,andTauIs).

P. s. nawaiensisJ. E. Gray, 1870 — Fiji Is (Vanua Levu, Taveuni, Viti Levu, Ovalau, Cicia, Nayau, Vanua Balavu, Vatu Vara, Kadavu).

Descriptive notes. Head—-body 175-220 mm (tailless), ear 20- 1-23 mm, forearm 120- 1556 mm; weight 220-440 g. Greatest lengths of skulls are 57- 3-64 mm. Subspecies nawaiensis is smaller and has weaker teeth than nominate samoensis . The Common Samoan Flying Fox has small rounded ears, partly hidden in fur, and long grizzled pelage. Dense pelage and wings are dark brown. Fur on head, neck, and back varies from sandy oversilvery gray to brown. Crown of head is brightly colored. Mantle is buffy gray to dark chestnut or reddish brown in samoensis and ocherous buffy to yellowish white in nawaiensis. Mantle color extended to sides of neck and collar. Claw on index finger is well developed. Wing membranesare attached ¢. 25-26 mm apart from sides of back. Uropatagium is very narrow. Skull is robust, with very short snout. Coronoid process is higher than in the sympatric Pacific Flying Fox ( P. tonganus ). I, and P, are large; P' is less strongly reduced. Basal ledges of cheekteeth are strongly developed compared with otherflying fox species.

Habitat. Primary tropical moist forests and sometimes agroforests, plantations, and village areas.

Food and Feeding. The Common Samoan Flying Fox feeds on fruits, leaves, and flower parts, with fruits forming the biggest parts of diets. At least 32 plant species are used as food, including in Samoa, Carica papaya ( Caricaceae ); Dysoxylum maota ( Meliaceae ); Artocarpus altilis and Ficus spp. (Moraceae) ; Syzygium inophylloides ( Myrtaceae ; plants visited as flower source); Cupaniopsis samoensis (Sapindaceae) ; Freycinetia reinecker ( Pandanaceae ); Inocarpus fagifer ( Fabaceae ); Elaeocarpus tonganus (Elaeocarpaceae) ; Terminalia catappa ( Combretaceae ); Palaquium stehlinii and Planchonella spp. ( Sapotaceae ; plants visited as fruit or fruitlike pulp source); and Cananga odorata ( Annonaceae ). Nominate samoensis prefers fruits and inflorescences oftrees in primary forests but also feeds on coconut palms and A. altilis. Subspecies nawaiensis feeds mainly on nectar and sprouts of Pandanus (Pandanaceae) .

Breeding. The Common Samoan Flying Fox is monogamous. Breeding is broadly seasonal; mating occurs in August-December. During this time, a female usually also cares for her young from the last litter. Births occur in March-October, peaking in May-June. Young begin to fly at ¢.3 months old. Weaning occurs during peak fruiting.

Activity patterns. Nominate samoensis on the Samoan Islands is mostly diurnal, with foraging flights in morning and late afternoon, but it also has some night activity. Soaring using air thermals occurs during the day and subspecies nawaiensis on the Fiji Islands is less diurnal and does not forage until late afternoon, possibly to avoid predation by peregrine falcons (Falco peregrinus).

Movements, Home range and Social organization. Male Common Samoan Flying Foxes defend territories of ¢. 3 km?®They mark branches and tree trunks with secretion from neck glands. Territorial behavior also includes aerial pursuits, vocalizations, and display on clearly visible branches. Females also show territorial behavior, but it is less strongly pronounced. Actively defended territories are c. 2 km? occupied by couples year-round, and are maintained by vocalizations, glandular scent marks, and wing displays. Both partners chase intruders.

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Status and Conservation. CITES Appendix I. Classified as Near Threatened on The IUCN Red List. In the 1980s, numbers of nominate samoensis declined sharply because it was commercially captured for export as a luxury food to Guam and Northern Mariana Islands. Because international trade has been banned since 1990, this is no longer a threat. Hunting for the local market is not a major threat in Fiji, but it is in Samoa and American Samoa. There is a temporary ban on hunting in American Samoa, but this is hardly known among citizens. Main threat now is habitat loss from deforestation and conversion into agricultural land. Typhoons and other catastrophic weather events are also a threat. In the 1990s, overall population of the Common Samoan Flying Fox was weakened by storms that destroyed food sources. Some important roosting and foraging places are in protected areas (e.g. American Samoa National Park). Nevertheless, additional protection is needed to help population recovery.

Bibliography. Almeida et al. (2014), Andersen (1912b), Banack (1998, 2001), Banack & Grant (2003a), Brooke (2001), Brooke & Wiles (2008), Brooke et al. (2000), Cox (1983), Dobson (1878), Flannery (1995a), Gray (1870), Koopman & Steadman (1995), Melin et al. (2014), Mickleburgh et al. (1992), Nelson et al. (2000), Palmeirim et al. (2007), Peale (1848), Richmond et al. (1998), Russell et al. (2016), Simmons (2005), Thomson et al. (1998, 2002), Tsang (2015), Wodzicki & Felten (1975, 1981).

Figures

161. New Britain Masked Flying Fox (Pleropus capistratus), 162. New Ireland Masked Flying Fox (Pleropus ennisae), 163. New Caledonia Flying Fox (Pteropus vetula), 164. Common Samoan Flying Fox (Pteropus samoensis), 165. Banks Flying Fox (Pteropus fundatus), 166. Vanuatu Flying Fox (Pleropus anetianus), 167. Vanikoro Flying Fox (Pleropus tuberculatus), 168. Temotu Flying Fox (Pteropus nitendiensis), 169. Solomons Flying Fox (Pteropus rayneri), 170. Makira Flying Fox (Pteropus cognatus), 171. Rennell Flying Fox (Pteropus rennelli), 172. Temminck’s Flying Fox (Pteropus temminckui), 173. Gray-headed Flying Fox (Pteropus poliocephalus)

Subspecies and Distribution. P.s.samoensisPeale,1848—WesternSamoa(SavaiiandUpoluIs)andAmericanSamoa(Tutuila,Ofu,Olosega,andTauIs). P. s. nawaiensisJ. E. Gray, 1870 — Fiji Is (Vanua Levu, Taveuni, Viti Levu, Ovalau, Cicia, Nayau, Vanua Balavu, Vatu Vara, Kadavu).