Blyth's Hornbill Aceros (Rhyticeros) plicatus Beautiful Bully of Seram Forests

Abstract

You might think that after a week sitting in a tree, waiting for the perfect hombill photo, that I would be thrilled to see a hombill land just two meters away. You'd think that after countless hours staring through an empty viewfinder, wishing a hombill into place, that I would be ready for one to arrive. Think again.

A male Blyth's Hornbill, like this one I met in Seram, Indonesia, has a wingspan of about one and a half meters (approx. 5 feet). This, in itself, isn't terribly impressive. What is impressive is that those one and a half meters of wings have no underwing coverts - no silencers of any sort. So when two kilos ( 4 '/z pounds) of Blyth's Hornbill fall from the sky-THWUSH-THWUSH-THWUUUUUUUSSHH! - when they crash into the rainforest canopy just two meters above your head, the impulsive reaction isn't swinging a camera into position. It's more like "Incoming!" After that, it's just duck and cover. In a pinch, SOOmm of long, fast telephoto can double as a great bomb-shelter.

But despite their size, or perhaps because of their size and apparent awkwardness, hombills are wary of ducking humans. By the time I peeked up, this hombill was launching off in labored wing beats. He looked about as surprised as I was. Within seconds, he'd settled into an obscured position in a neighboring tree. As usual, he began his insistent tirade to no one in particular. "WRA-wra-wra-wra-wra-WRA-WRAwra-wra-wra ... "Three minutes later, he still sounded like a grumpy old man

 

with a long list of complaints.

This hornbill probably really was an old man. In Indonesia, the Blyth's Hornbill is known as tahun-tahun, or, roughly translated, "many years." Local bird trappers claim these birds gain a single ridge on their casque every year, for up to seven years. As trappers are unrivaled for their observation time in the forest, I tend to trust them. This hombill had seven ridges, leading me to believe it was at least seven years old, probably older.

Hornbills are the bullies of the Serarn forest. Even the proud and cantankerous Salmon-crested Cockatoo will surrender to tahun-tahun. In fact, this hornbill nest cavity that I'd staked out for photography was, in all likelihood, stolen from cockatoos.

As any cockatoo owner will tell you, cockatoos are champions at tearing things apart. In the Seram forest, cockatoos play vital roles as nest cavity excavators. Many other birds will occupy a cockatoo _nest once abandoned. Hornbills will occupy a cockatoo nest before it's abandoned. Bird

 

trappers report dramatic battles when a pair of hornhills takes on a pair of cockatoos for an occupied nest. The screams must be near-deafening. Generally, the higgcr and hadder hornbills win. Any leftover cockatoo eggs make a nourishing hornbill snack. The female hornhill then moves in and occupies the nest.

Unlike most hornbills, the Blyth's female does not physically lock herself inside the nest. Dr. Margaret Kinnaird, who has researched Indonesian hornbills extensively under the Wildlife Conservation Society, has speculated that the degree of nest closure correlates to the potential threat of nest predation and intraspecific competition. As Serarn has few nest predators, and no viable contenders for nest cavities, these observations add strength to her argument.

The female Blyth's does maintain her ground at the nest as she incubates and rears her young, however. Trappers claim the female does not leave until her young fledges. By then, they say, she is weak and stiff and flying does not

 

appear easy for her. Kinnaird, however, claims that most Aceros females are lazy, leaving the nest two to three weeks prior to fledging, then refusing to help with feeding. This matter will require further clarification in the field.

Though hombills are bullies, they are not completely safe from predators. Giant pythons may invade the nest, and the nesting female is always wary of the clawsteps of soa-soa, a tree-climbing monitor lizard that grows about a meter long. Even the Seram bird trappers are fond of young hornbill meat. "Kalau masih gemuk, enak!" they claim. Delicious when still fat. Fortunately, hunting of hombills is rare, and almost certainly sustainable, in the villages where I've stayed.

To the hornbill's benefit, their unfriendly disposition makes them poor candidates as cage-birds. But with mounting pressure on Salmon-crested Cockatoo populations due to trapping for the pet trade, the availability of nest cavities for hornbills and other birds is likely jeopardized.

Once that male hornbill in the adjacent tree had given up complaining, he flapped up to his nest cavity, about ten meters from where I'd set up my camera. He stalled on approach--WHOOOSH1-then latched onto the lower rim of the cavity. He hung slightly, but propped himself up from below with his stiff tail feathers.

The hornbill's first gift for his mate and young was the plump fruit of a strangler fig. The abundant harvests from this tree, alone, may account for the popularity of August and September as a nesting season in Seram. On other visits, the hombill's first gift had been fresh lizards or insects. Hornbills easily have the most eclectic diets among Seram birds.

On this trip, tahun-tahun lived up to his reputation as an Indonesian symbol of fidelity. He carried with him perhaps half a dozen edible gifts.just as he deposited one morsel in the nest, he pried

 

his bill open against the rim of the cavity and regurgitated another fruity gem. Though his giant bill seemed an ungainly tool, it manipulated with the precision of fine tweezers. One more fruit disappeared into the nest, and another appeared from his crop. He might have been a magician pulling rabbits from a hat.

From this safe distance, I snapped off a quick roll of photos. The weather and the light and the Kamikaze hombills had finally cooperated. I rappelled down from my tree blind as fulfilled as the well-fed hornbill mother and chick. My work here was done, but for the male Blyth's hornbill, the chores will never end. ~

 

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