Monday, December 24, 2018

Spot-billed Pelicans in the Dry Zone Sri Lanka


A severe drought which continued for almost three years in the North Central Province has come to an end with the monsoon rains this year - 2018. A land that flourishes a unique hydraulic civilization and a network of water storing tanks or ponds called “Wewa” in native Sinhala are full to capacity. The paddies below the tanks are tilled and sown giving a lush hue of fading green. A pleasing site at dawn, with the night’s mist clearing in the morning streaks.  

Typical layout of a cascading tank irrigation system


Our night stay in Rambawewa within the watershed of a medium sized tank was full of water and the extended spread of water leading into a growth of shrub and vegetation thriving on the once rich silty tank bed.

Up early morning with binoculars, camera and the bird activity in the water spread skirting right up to the benches placed on the periphery of the property to sit and enjoy the aquatic environment was very pleasing. From the behind came the high pitched honking of a peacock on a “Mango tree” Mangifera indica …. it’s night peach waiting for the sun to come up.




Purple Heron
Large Egret
Five Spot-billed Pelicans are feeding among the reeds and short shrubs in the shallow stagnant water. It is amazing to note that all five pelicans are feeding individually and their success rate is very high. Generally the pelican hunts as a team cornering the fish and attacking them in unison. It was different over here in the very shallow water. The shape in the shrilled shadow through its pouch membrane against the sunlight shows them to be fairly large catfish.


These man-made water-bodies are used to store rainwater for a six month season of cultivation and the water is released to a pre-planned schedule. The tank water level decreases with the water issue and the last waters are held close to the bund which is the deepest location in this water systems. Likewise the aquatic life too gets into a cycle where the nutritious vegetation in the outer spread gets attracted by the carps, tilapia and the catfish that feed on them. Gradually with the water being drained for irrigation the fish get a limited feeding area and finally gets confined in the puddles and pools and become prey to many water birds, otters and small wild cats.

Intermediate Egrets in flight.
However catfish being air breathers they bury themselves in the mud pools keeping their skin moist and survive the interim period until the next rains are in filling the tank for another season with a fresh aquatic cycle. In the case of the tilapia; its eggs survive and are even transferred from one water body to another by travelling over land stuck in the feet of most water birds. This being the secret for fish to occur in any new water-body.



Getting back to our pelicans …… it is these catfish that had buried themselves in the mud and are now active in the outer reaches of the tank feeding on the grasses in the shallow waters that turn out as prey to the pelicans. The water being shallow and the catfish being a slow mover is easy prey to the pelican not needing teamwork?










It’s fascinating to see the sequence of the pelican spotting the fish and attacking which was almost always successful. No sooner it spots the fish the head is pushed right back with the pouch and the bill tightly sunk in the stooping frontal part of its body until the stabbing attack with a high-speed leap takes place securing the prey in its pouch with the head swung in an upward movement.

Birdwatching is much more fun and engrossing when you study their behavior and understand the reason for such behavior.  

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