Pteropus chrysoproctus (Temminck, 1837)

Tsang, Susan M., Wiantoro, Sigit & Simmons, Nancy B., 2015, New records of flying foxes (Chiroptera: Pteropus sp.) from Seram, Indonesia, with notes on ecology and conservation status, American Museum Novitates 2015 (3842), pp. 1-24 : 7-11

Pteropus chrysoproctus (Temminck, 1837)

Moluccan flying fox

TYPE LOCALITY: Ambon, Central Maluku , Indonesia.

NEW MATERIAL: Pulau Raja , offshore from Sawai, Maluku Tengah Regency, Maluku Province, Indonesia. Collected by Sigit Wiantoro and Susan M. Tsang , 3 females : MZB 36908, MZB 36909, MZB 36910 , 1 male MZB 36911 .

OTHER SPECIMENS EXAMINED: MZB 0219, MZB 1076, MZB 1077, MZB 1078, MZB 13568, and ZMB 2626.

OCCURRENCE AND IDENTIFICATION: Pteropus chrysoproctus is rare in collections, but likely not uncommon despite anecdotal evidence of historical decline according to the IUCN red list assessment ( Huston and Helgen, 2013). The individuals encountered at Pulau Raja in Seram resemble specimens from older collections purportedly from Ambon and Seram, including the poorly preserved syntype in Berlin (ZMB 2626). Unlike the other three sympatric species, the ears (> 30 mm) are distinctly longer than the CM2 length. The pelage is dark reddish brown over most of the body, appearing a bit brighter on the ruff and darker red on the belly—another unique characteristic among Moluccan species. Compared to the sympatric P. melanopogon , P. chrysoproctus is smaller in size and has a much narrower skull: FA 170–180 mm, GSL 63–77 mm, ZB 31–42 mm, LIOW 8–10.5 mm (compared to FA> 185 mm, GSL> 75 mm, ZB> 40 mm, LIOW> 10 mm in P. melanopogon ) ( tables 2 and 3). Similarity between individuals from Ambon and Seram is important to note, as populations of P. chrysoproctus from different Moluccan islands may represent distinct subspecies or species (K. Helgen, personal commun.).

HUMAN DISTURBANCE: Hunting of P. chrysoproctus , along with habitat loss, threatens the species. Thought to occur only in small groups, our survey found a roost of approximately 300 individuals in a patch of mangrove trees (primarily Rhizophora sp. ) near Manusela National Park. According to the local villagers in Sawai and forestry rangers, the roost is present yearround and will likely not be lost to development in the near future since it is protected as an ecotourism attraction by local resorts. However, according to forestry rangers, this is the only roost site for this species currently known on Seram. There were no indications of presence of P. chyrsoproctus colonies at any of the other sites we surveyed.

Anecdotal evidence suggests that these bats have been hunted intensely and have either moved permanently or are locally extirpated at other sites. According to the local people, P. chrysoproctus , along with P. temminckii , were once the most commonly encountered species by hunting parties seeking Pteropus , particularly at their foraging sites. Patchy forests near villages such as Mosso in Central Seram were known to be foraging areas for many pteropodids, including Pteropus , Nyctimene , and Syconycteris . Through interviews with local residents, we learned that Muslim villagers do not enter the forest to forage because of their belief that it is a sacred area, but Christian villagers from the other side of the forest enter often to hunt bats. The Christian villagers stated that there were more bats in the area in the past decades than there are now, and described three distinct types: the “red one” (likely P. chrysoproctus ), the “white one” (likely P. temminckii ), and the “black one” (likely P. melanopogon ). We concluded that the “black one” was P. melanopogon and not P. ocularis based on size descriptions (“very big”) and distinct markings (“white belly”), and we were able to confirm this visually when we were shown a small group of P. melanopogon by villagers in the nearby forest.

Villagers near Manusela National Park customarily go into stands of kapok trees ( Ceiba pentandra ) where Pteropus were known to forage in order to shoot bats for food. It is customary for the men to hunt Pteropus as an appetizer for drinking parties. Even if roosting sites are within the limits of a national park, there is no guarantee of protection for Pteropus species because the bats may be vulnerable to hunters when foraging outside park boundaries. Forestry rangers indicated that after severe storms battered the mangroves in 2010, the colony of P. chrysoproctus temporarily moved to areas surrounding the national park, including villages where bat consumption is common. The P. chrysoproctus population was purportedly much larger prior to this storm.

CONSERVATION: Pteropus chrysoproctus is currently listed as Near Threatened by the IUCN, but our data suggests that the species should be listed as Vulnerable under criteria B1a, b (iii, iv). This categorization means that the extent of the species occurrence is less than 20,000 km 2, with fewer than 10 known localities, and continuing decline in both habitat and number of subpopulations. It is extremely unlikely P. chrysoproctus is still on Ambon since its colonial behavior would attract the attention of the local forestry rangers. While the colony of P. chrysoproctus in Sawai is an ecotourism attraction and will likely remain undisturbed, it is not under the protection of Manusela National Park nor local forestry services. The site merits some official level of recognition for its uniqueness and high conservation value.