BSERVATIONS ON THE NESTING OF THE BROWN WOOD OWL,
STRIX LEPTOGRAMMICA OCHROGENYS IN GANNORUWA FOREST RESERVE, SRI LANKA
V.A.M.P.K. Samarawickrama 1*, K.B. Ranawana1 & V.A.P. Samarawickrama2
1 Department of Zoology, Faculty of Science, University of Peradeniya, Peradeniya.
2. IUCN- World Conservation Union, No. 53, Horton Place, Colombo 07, Sri Lanka.
Accepted 04 May 2006
In Sri Lanka, Family Strigidae is represented by nine species of owls belonging to seven genera. Of these only the two species, Chestnut-Backed Owlet (Glaucidium castanonotus) and the recently discovered Serendib Scops Owl (Ottus thilohoffmani), are considered to be endemic to Sri Lanka. The Brown Wood Owl, Strix leptogrammica ochrogenys is a common member of the Family Strigidae. It can be distinguished from all other species of owls in the country by the slight red-brown facial disk surrounded by a wide black border. The upper part of the body is brownish and striped. The throat is white and the rest of the lower part of the body is pale coloured with chocolate brown coloured stripes. Eyes are brown.
The study on the Brown Wood Owl was carried out in a home garden bordering the Gannoruwa forest reserve in the Kandy district of Sri Lanka. A nest of the Brown Wood Owl was found in a tree hole (Jack tree - Artocarpus hetrophyllus) about 10 m above the ground. The tree hole was 45 cm wide, about 60 cm long and about 90 cm deep. Observations on the nest were made during the day and at night once a week throughout the post breeding season, extending from early December to end of March. Observations on the same nest were carried out for four consecutive years. Two pale white-coloured, ellipsoid-shaped eggs which are 48.8 mm long and 43.2 mm wide are laid in the nest. The eggs were laid on two consecutive days and incubated only by the female for about 25 – 30 days. The hatchlings totally depended on the parents for two months. They were fed with a variety of prey items including, 85% small mammals such as rats (Ratus spp.) and Palm squirrels (Funambulus palmarum); 11% birds including Brown-headed barbet (Megalaima zeylanica) and Yellow-fronted barbet (Megalaima flavifrons) and 04% reptiles including Green garden lizard (Calotes calotes). These food items were identified by examining and analyzing left-over food that contained parts such as feathers, hairs, bones and skulls found in the nest and in the ground under the nest.