The endemic Sri Lanka Grey Hornbill (Ocyceros gingalensis), breeds inside natural tree cavities as in the case of other hornbill species https://besgroup.org/2008/07/09/oriental-pied-hornbill-breaking-out-of-its-nest/. As forests disappear as a result of habitat loss and deforestation, tree cavities become scarce. When tree cavities are available, they are always in demand by owls, woodpeckers, monitor lizards, bats, rodents, etc. https://besgroup.org/2019/08/19/are-there-too-many-hornbills-in-singapore/
Unable to locate their usual nesting hole, hornbills have been known to make use of other cavities. In one case, the nesting “hole” was a large jar lying on the ground https://www.tiktok.com/@chris_smit1/video/7150524760907140357. In Singapore, wooden nesting boxes proved useful in luring Oriental Pied Hornbills to nest. https://www.nparks.gov.sg/-/media/cuge/ebook/citygreen/cg4/cg4_14.pdf
In the North Central Province of Sri Lanka a nest was located in an urban home garden. A large aluminium pot that was tied to a mango tree was used by a pair of Sri Lanka Grey Hornbill. The pot was tied to the mango tree about 1.8 meters from the ground. It was 40 cm in diameter at its widest and its opening was 13 cm wide.
From March to July 2023, regular observations were made from a hide about 10 meters away. Observations were made every 15 minutes from 0600 to 1800 hours two days a week.
A clutch of eggs was laid in the last week of March 2023, hatching by the end of April.
Five months later the chicks fledged. Prior to nesting the pair of hornbills were observed flying around, probably looking for a nesting site. The female hornbill was seen entering the pot a few times cleaning the inside. This is not the only case of nesting in pots. Earlier, a pair of Oriental Pied Hornbill (Anthracoceros albirostris) was reported nesting inside a large earthen pot lying on the ground. https://besgroup.org/2010/03/07/oriental-pied-hornbill-nesting-in-earthern-pot/
Faecal samples and seeds found below the nest were collected.
The entrance to the nest was sealed, leaving a narrow slit to allow the male to feed the female and later, the chicks. The male arrived regularly, bringing fruits, insects, an occasional snail, string hopper or a lizard.
In the last week of March 2023 a clutch of eggs were laid. Incubation took about 30 days. During this time the male feeds the female fruits, insects and occasionally snails. By the end of April the eggs hatched and the chirpings of the chicks were often heard. By 12 June the female hornbill broke through the entrance.
Once the feathers of the chicks, especially the tail feathers became well developed, the chicks were lured out of the nest. By 9th of July all three chicks had fledged.
As nesting holes are scarce in Sri Lanka, artificial nests using aluminium pots can be provided in various locations to increase the population of these Sri Lanka Grey Hornbills.
NOTE: The above is a summary of the paper prepared by Damindu J.C. Wijewardana1, Iresha I. Wijerathne and Sriyani Wickramasinghe of Sri Lanka. The paper, Observation on an artificial nest of a Sri Lanka Grey Hornbill (Ocyceros gingalensis) in an urban setting was published in the IUCN SSC Hornbill Specialist Group’s journal “Hornbill Natural History and Conservation Vol. 5”. Paper can be accessed using this link https://iucnhornbills.org/hnhc-vol-5/
Damindu J.C. Wijewardana, Iresha I. Wijerathne and Sriyani Wickramasinghe
