Sky-high over Borneo’s tropical rainforests
Borneo’s bird fauna is slightly less rich than that of Sumatra but it has more endemic species, particularly in montane areas. The reason for this is that in geological time, mountains remained as 'evergreen islands' when Borneo's drier lowlands were periodically linked with the Asian mainland.3
Borneo hornbills, cultural and ecological symbolsHornbills are of considerable cultural importance and abstract forms of their beaks can be found on many Dayak motifs. Ecologically, hornbills such as the bushy-crested (Anorrhinus galeritus), helmeted hornbill (Rhinoplax vigil), and great rhinoceros (Buceros rhinoceros) are important seed disperses of many fig trees (Ficus species).
The 2 largest hornbills, the rhinoceros hornbill and the helmeted hornbill, are declining as they have been affected by the selective removal of large nesting trees. They are also hunted for their meat and for their tail feathers, used for traditional costumes and dancing.
Hunting is causing populations to decline or become locally extinct, a problem that is exacerbated by the birds’ slow breeding rate and low natural densities.4 Five of the 8 hornbill species are now listed as "Near Threatened" on the IUCN's Red List of Threatened Species.
Although these long-lived birds often persist in logged-over forests for many years, they do not breed if there are no suitable cavities in large trees.
A stopover on Borneo for long-distance flyersEvery year, Borneo is visited by many bird species from temperate regions that choose to over winter on the island.
This period corresponds to the fruiting season, which provides much needed food resources for frugivorous (species that eats only, or mostly, fruit) migrants. Mt. Kinabalu (Sabah), is one of the areas in Borneo that provide relatively stable fruit resources for many frugivorous birds.5
More than 3 species discovered every month during the past 15 years
An elusive new bird species
The bird is an attractive grey colour with bright white arcs above and below the eye, a white throat extending as a broad white stripe down the centre of the belly, and white tufts at the breast sides.
The name given to the species refers to the bird’s prominent eye-rings.
2 MacKinnon J, Phillipps K. 1993. A fieldguide to the Birds of Borneo, Sumatra, Java and Bali. Oxford University Press.
3 Bennett, EL, Nyaoi, AJ, Sompud, J. 1997. Hornbills Buceros spp. and culture in northern Borneo: Can they continue to co-exist? Biological Conservation [BIOL. CONSERV.]. Vol. 82, no. 1, pp. 41-46.
4 Bennett, EL, Nyaoi, AJ, Sompud, J. 1997. Hornbills Buceros spp. and culture in northern Borneo: Can they continue to co-exist? Biological Conservation [BIOL. CONSERV.]. Vol. 82, no. 1, pp. 41-46.
5 Kimura K. Undated. Tropical Montane Forest in Borneo as a Source of Fruit Supply for Frugivorous Birds. pp113-122.