Abstract

A. Mohamed Samsoor Ali, S. Asokan and R. Manikannan

The nesting ecology of the White-breasted Kingfisher Halcyon smyrnensis was studied in Cauvery Delta of Tamil Nadu, Southern India between 2005 and 2006. A total of 46 nests were studied and the White- breasted Kingfishers were found to excavate long tunnels ranging in length from 48 - 152 cm (mean 114.1 ± 1.7 cm) and ending in widened egg chambers. The mean length and circumference of the nest entrance hole opening was 10.4 ± 0.2 and 27.9 ± 0.8 cm, respectively. They excavated nest holes at a mean height of 207.5 ± 15.2 cm from the bottom and 96.6 ± 3.2 cm from the top of sandy river banks. The clutch size varied from 3 - 5 with a mean of 3.7 ± 0.82 and clutches of three were very common. The egg dimensions (length x width) ranged between 37.5 x 25.3 mm and 28.4 x 21.6 mm. The weight of the eggs varied between 8.0 and 10.0 g (mean 8.9 ± 0.65 g). The mean incubation period of the whitebreasted kingfisher was 15.3 ± 1.12 days. The newly hatched nestlings were 3.7 g in weight and reached a maximum of 70.5 g on day 24. A reduction in weight was noticed in the last few days and 61.8 g was recorded on day 27. The other body parts attained maximum maturity from hatching to fledging. The white-breasted kingfisher laid 88 eggs, of which 82 hatched (93%) and 66 flew out of the nest, making the fledging success 80%.