In June 2007, we posted an account of infanticide-cannibalism among the Oriental Pied Hornbills (Anthracoceros albirostris), documented by the Singapore Hornbill Project.
At the recent 5th International Hornbill Conference held in Singapore, Prof Ng Soon Chye presented further evidence of infanticide-cannabilism among these hornbills.
From June 2005 to August 2007, ten breeding cycles were monitored in Singapore’s offshore island of Pulau Ubin on five breeding pairs. Another six breeding cycles involving three pairs were also monitored at the Jurong BirdPark during the same period.
Infanticide-cannibalism, whereby the female kill a chick and feed it to the remaining chicks, is relatively common among these hornbills. It was observed in 60% of the breeding cycles. It occurs in the wild as well as in captivity, in natural as well as artificial cavities.
Victims are usually the youngest and thus the weakest chick, the last chick to hatch in a brood of three or four. In one case, the second chick in a brood of four died naturally whereby the female ate it up. She later killed the third chick and fed it to the others. The fourth chick survived to fledge.
In another incident when the artificial nest was flooded and the three chicks (2-6 days old) drowned, the female ate them up eight hours later. She continued to incubate the remaining un-hatched egg but eventually broke out from the nest when it failed to hatch.
Reference:
Observations of infanticide-cannabilism in the Oriental Pied Hornbill (Anthracoceros albirostris) by Ng Soon Chye, Lai Huimin, Mark Lim Tee Sin, Sadali b Mohd. Tali & Marc Cremades. Paper presented at the 5th Intn. Hornbill Conference, Singapore, March 2009.
4 responses
This is a great finding but can insufficient food may lead to this act? Had this report incorporated food survey around the nesting area before making such conclusion?
My view is that this has nothing to do with food shortage outside the nest. Rather, it may be about food availability inside the nest… and keeping the brood vigorous by killing off the weakest chick.
In another presentation by keynote speaker Alan Kemp, he noted that with the African hornbills he studies, the female usually lays 2-3 eggs but only one chick, usually the eldest, survives. He believes this to be a form of ‘insurance’ should the first chick dies or gets predated, rather than due to food shortage.