Pteropus ocularis ( Peters, 1867 )

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 : 16-17

Pteropus ocularis ( Peters, 1867)

Seram flying fox

TYPE LOCALITY: Seram , Central Maluku, Indonesia .

NEW MATERIAL: Pulau Marsegu, Seram Bagian Barat Regency, Maluku Province, Indonesia. Collected by Sigit Wiantoro and Susan M. Tsang, 1 male MZB 36928 .

OTHER SPECIMENS EXAMINED: MZB 0112, MZB 13361, AMNH 234939, ZMB 2958. Additional specimens that we did not examine for this study are housed at the AM and BMNH.

OCCURRENCE AND IDENTIFICATION: Pteropus ocularis is a species that is very rare in collections. We suspect P. ocularis is unlikely to be found in colonies based on our inability to locate any colonies, the lack of historical or current colony information from local forestry rangers, and having captured an individual under similar circumstances as the other noncolonial Pteropus species , P. temminckii . The IUCN red list assessment of P. ocularis states that it has been collected only four times ( Helgen and Salas, 2013b) although we are aware of six previous records: the holotype collected by Alfred Russel Wallace (at ZMB), two females (one collected in 1915 and another from 1982) housed at MZB, a series at BMNH, a series from Ambon at NMNL, a female at AM in Sydney ( Flannery, 1995), and a male at AMNH with vague locality data (“ Moluccas ”). The MZB and BMNH specimens are from Buru, whereas the AM specimen is from an area near Manusela National Park, Seram. Unfortunately, the tag on the holotype and the original description by Peters (1867) only states that it is from Wallace’s “Ceram” collection. We are doubtful of the species identity of the AMNH specimen because the forearm length (FA = 118 mm) is significantly smaller than expected, and we also ruled out the possibility that it was not a mature adult. Additionally, the ventral fur has a distinct, large, light blond patch that is not characteristic of P. ocularis . We could not further investigate because the skin is in such poor condition with the skull still inside.

Our collection of P. ocularis is likely the first record from West Seram. Our identification of this specimen is based on pelage pattern and morphological measurements. Dobson (1878) noted that that P. ocularis has distinctive light reddish-brown rings around the eyes similar to P. conspicillatus , however, P. ocularis is much smaller in size and the body shape of P. ocularis is “ Pteropus griseus -like” with an interfemoral membrane that is narrow in the middle. Our specimen conforms to this description. Our specimen also falls within the expected range of measurements for this species: FA 130 to 145 mm, GSL 59 to 63 mm, ZB 32 to 34 mm, LIOW 6 to 7 mm ( tables 2 and 3, fig. 2 ).

Our specimen was captured in a mangrove forest. The IUCN red list assessment states that P. ocularis “probably occurs only in old growth forest,” but the habitat of this specimen indicates that more extensive surveying is necessary to understand the habitat preferences of this species.

HUMAN DISTURBANCE: It remains unclear whether P. ocularis faces persistent, targeted hunting pressure like P. chrysoproctus and P. melanopogon since it is a solitary species and relatively rarely encountered. There were no indications that the local villagers knew this species very well from any particular location, but they may consume it as a result of incidental capture.

CONSERVATION: P. ocularis is currently listed by the IUCN as Vulnerable B1 a, b (iii, v). 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. Deforestation in and around Manusela National Park probably affects this species. It is unclear whether the apparent rarity of P. ocularis is due to low relative abundance or cryptic behavior or whether populations are declining. Further monitoring is necessary to determine whether an IUCN Endangered status may be more appropriate for P. ocularis than its current one of Vulnerable.

Figures

FIG. 2. Dorsal views of skulls of A, Pteropus chrysoproctus (MZB 36909♀); B, Pteropus melanopogon (MZB 10753); C, Pteropus ocularis (MZB 369283); D, Pteropus temminckii (MZB 369253).