Friday, January 7, 2011

Sabah: Kinabatangan - Land of the Hornbill

Hornbills are remarkable creatures, to say the least. By turns awkward-looking and majestic, they are head-turners for even the most blasé non-birder. Their natural history is unique - in all but the two ground hornbills of Africa, males seal their females into the nest cavity with a plug of sun-hardened clay until their young are ready to emerge. Hornbills are vital fruit dispersers in tropical forests, and their conservation - a matter of considerable concern throughout tropical Asia - may be vital to the health of the whole forest ecosystem.

In Borneo, hornbills have been cultural icons for centuries. The image of the Rhinoceros Hornbill (Buceros rhinoceros), often stylized into an almost abstract figure, its upturned casque teased out into a swirling spiral, is a central
motif in Iban art It has become the symbol of the state of Sarawak, prominently featured on its coat of arms.

The official "Land of the Hornbills" is, indeed, Sarawak, but actually finding hornbills in Sarawak today can, unfortunately, be a challenge. Along the Kinabatangan River in Sabah, hornbills remain easy to see. Of course that delighted us as visitors - but it made us wonder, as conservationists, about what we were really seeing.

Hornbills are long-lived creatures, and that can make it difficult to judge how healthy a population of wild birds really is. Are the birds that crowd along the river representatives of a healthy population in a flourishing ecosystem, or are they aging remnants unnaturally forced into a remaining strip of forest by the spread of oil palm? Are the birds still breeding successfully? If not, how much longer will they be a feature of the river? I don't know the answers to these questions, but I would very much like to.

Anyway, here is a Kinabatangan hornbill gallery, featuring five of Borneo's eight species photographed as they perched on forest trees or flew majestically over the river - including two that I was seeing, to my great delight, for the first time.

To see the most widespread species, the Oriental Pied Hornbill (Anthracoceros albirostris), we didn't even have to leave our bedroom. On our first morning, birds came down to raid our hosts' papayas.

The Pied is the smallest of Malaysia's hornbills, and the only one likely to be seen any distance from primary forest.

Our other hornbills revealed themselves during our jaunts along the river. Black Hornbills (Anthracoceros malayanus) are larger cousins of the Oriental Pied, and may be the second-commonest species on Borneo. This bird, with an ivory-white bill and broad and rather dashing white eyebrow, is a male.

The female is a blacker bird with a darker, less impressive bill.

This is the largest and most spectacular of the lot, a bird I had long wanted to see - our only Helmeted Hornbill (Bucorvus vigil). While many hornbills boast expanded casques perched atop their bills, the Helmeted is the only one whose casque is largely solid clear through (in the others, the casque is largely hollow, supported by a network of internal struts). Male Helmeted Hornbills need sturdy casques. Males apparently indulge in midair head-butting contests, as though they were some sort of flying goat. The sounds as they collide in flight reportedly resound through the forest like cannon shots. Now that is a bit of bird behaviour I would love too see!

Humans have made the head-butting weapon of the Helmeted Hornbill something of a liability. Because they are solid and can therefore be carved, their bills have become the only source of "hornbill ivory". Fortunately, unlike real ivory, hornbill ivory has never become an item of international commerce, and so there are still Helmeted Hornbills around for us to see.

My second new hornbill was one of the most colourful of the lot, at least as far as the bare skin around it's face is concerned. This is a Wrinkled Hornbill (Aceros corrugatus), marked with facial colours to rival the most brilliant of the (quite unrelated) toucans.

Finally, the most emblematic hornbill of all, the Rhinoceros. We saw quite a few on our excursions, always in pairs; hornbills apparently mate for life, a life that may last 70 years in the larger species.

For me it was a telling point that Eileen, born and raised in Sarawak, had never seen this symbol of her state in the wild before. I would hate to see the day when the only Rhinoceros Hornbills left in Sarawak were on the cost of arms!

1 comment:

  1. i hope it will come here to a 10 acre land next to jesselton condo & taman sinar baru, lrg kenawai 7D, kota kinabalu