Oriental Pied Hornbill: Failed nesting at Changi
Posted by BESG on 17 May 07, Thursday
Contributed by YC & Melinda Chan
There were two reported cases of Oriental Pied Hornbills (Anthracoceros albirostris) nesting in Changi in February 2007. The female hornbill was sealing herself in the shorea cavity fron 8-21st Ferbruary while another was sealing herself in an angsana cavity from early February to the 24th. Based on the observations made in Pulau Ubin, the female would remain in the nest from 65 to 78 days. This would imply that the bird would emerge from the nests between late April and early May.
No details are available for the shorea nest but it is believed the bird broke out sometime in April and was not seen to return. As for the angsana nest, the bird was still inside on 6th April. The image above was taken on that day showing the male above the nest, behind a newly emerged leafy branch. The image below (top), taken 16 minutes later, shows the male feeding her. However, in mid-April the bird broke out of her nest. A nearby resident reported seeing her emerging from the nest and flying away. Again, she did not return to the nest. This would imply that there were no chicks to feed.
The images below show the angsana cavity ten days apart at about the same scale. Note the size of the openings - the top with the bird still inside while the bottom showing the mud seal broken. The entrance has remained unsealed.
Usually, once the chicks are big enough, the female breaks the seal, leaves the cavity and the chicks inside reseal the entrance. They would emerge a few days later. Sometimes she will emerge followed by her chicks on the same day.
The fact that the cavity was not resealed and the birds did not return means that nesting must have failed. It is possible that the eggs were infertile and failed to hatch. Apparently this appears to be relatively common in the wild population in Pulau Ubin as well as the captive birds at the Jurong Bird Park. However, unless the nest is checked, this cannot be confirmed.
These are the first two cases of hornbill nesting in Changi. These two pairs of birds must have moved from nearby Pulau Ubin to seek out new territory. It is possible that they are first timers at breeding. Hopefully, subsequent nesting will be successful and we will see more hornbills around Changi.
Images by Chan Yoke Meng.
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Categories: Nesting-failed
Comment by Hai~Ren
Made Friday, 18 of May , 2007 at 1:38 am
Oh damn, and I was hoping to see the hornbills re-establish themselves as breeding residents. =( Oh well, hopefully in time to come they’ll breed successfully, and their progeny will come to re-colonise the rest of Singapore.
