When Hornbills Fly Past In Hundreds...

We were climbing the steep skid trail in a logging concession at the time. The weather had been wet all morning, drizzling rain, but that had stopped about an hour earlier. The others in the group lagged behind to examine a cleared area where a tree had been felled, and I walked on up to the top of the ridge.

Standard bird watching fare: a party of "little brown jobs" (in this case, Brown Fulvettas), a couple of Yellow-bellied Warblers, a sallying Dark-sided Flycatcher, a noisy Greater Raquet-tailed Drongo. And then the sound that makes all bird watchers jerk their heads upwards: whoosh-whoosh-whoosh…the unmistakable steam-train approach of flying hornbills. And I was stuck under an unbroken canopy!

Frustrated, I just had to wait while a group of seven or so flew past -- wonderfully low -- and I was unable to even guess at their identity. I kept my fingers crossed that my companions (none of them out-and-out birdwatchers and most without binoculars) would count them and pick up enough pointers for identification. And then, no sooner had the whooshing sound died away, than another group was heard -- and another, and another, and another…

I tackled the downward slope at breakneck speed, heedless of the fact that rain had made it as slick as a bob-sled shute. I arrived at the cleared area muddy, mercifully intact, and just in time to raise my binoculars and fix on the very last bird in a group before it disappeared behind the trees: and there it was -- white-tailed, black-winged -- and with a smooth bill and unmarked pouch of ivory colour, both as bare as the proverbial baby's bottom. It was a Plain-Pouched Hornbill (Aceros subruficollis).

It was November 19th 2001 and we -- Dionysius Sharma and Mohd Azlan Jeyasilan, and botanists Wong Khoon Meng and Philip Lepun -- were in the Temengor Forest Reserve, Perak, close to the Kelantan border, several kilometres south of the East-West Highway. This area borders the Lower Belum Forest Reserve, and the logging concession is in the heart of the main range. We were at an altitude of about 560m.

Ever since the first Malaysian Nature Society's Belum expedition produced massive numbers of over-flying hornbills in 1993, I had dreamed of seeing such a spectacle. And dreamed of it even more, when it was proven that at least some of the subsequent flocks appearing in the area were actually Plain-pouched Hornbills, a supposedly Thai-Burmese species never before seen in Malaysia. I had been to Temengor on numerous occasions, but had seen no more than a few isolated hornbills of the more usual species.

Fortunately for me, the 80 birds which had passed while my view was blocked were just the beginning. In the next hour and twenty minutes a total of 718 hornbills passed low overhead, of which a good proportion were definitely identified as Plain-pouched. Not quite as many as the largest recorded hornbill flypasts of over 2,400 -- but believe me, we felt like kids in a candy shop -- that's an average of one bird every six or seven seconds! Even the botanists forgot about botanising.

The birds were travelling from north-west to south-east, and may have crossed over the next range of hills (over 1000m) into Kelantan. They passed in groups varying from two or three birds to chevron skeins of more than twenty. The most common group size was five to seven individuals. They crossed on a broad front, and we may in fact have missed counting a number of groups because the distant view in both directions was blocked by trees. Two birds, one male and a female, perched for a brief time in a tree directly over our heads. Details of appearance were not easy to ascertain because of our hemmed-in position: we could observe through gaps in the canopy, either directly above, or -- because of the steep slope -- just higher than eye level, but only for brief periods of time as birds crossed the gaps. A frustrating situation for a birdwatcher, and there were many plumage details I missed as a consequence.

It is possible that not all the birds seen were Plain-Pouched Hornbills; in fact, several groups were tentatively suspected to be Wreathed, and one male and female pair that flew past further away (and may not have been part of the general flight) seemed to be Wrinkled Hornbills -- which are supposed to be flatland specialists! However, we later positively identified a pair of Wrinkled seen even higher up the logging road, so my identification was probably correct.

Male Plain-pouched Hornbills have short white tails, all black wings, and pale bills with a low casque. They have darker coloration on the bill base, and no marks on the pouch at the throat, unlike their similar cousins, the Wreathed Hornbills. Females are noticeably darker than males, having no white on their necks and heads; they also have blue pouches, rather like blue baby bibs worn at the neck. We found that the size and colour of male pouches varied: some were ivory, others -- the larger ones -- were bright yellow, and some were almost reddish-orange, especially in the folds near the head and neck. This may have been a phenomenon of breeding.

Read more in the July/August 2003 issue, available at leading bookshops now or email virtualmalaysia@cat.com.my for subscription.