Tuesday, September 12, 2006


C D Kaluthota, S N Gamage & U L S Kaluthota
Field Ornithology Group of Sri Lanka, Department of Zoology, University of Colombo

Painted stork is a Near Threatened species that uses wetlands as their feeding and breeding grounds. The breeding colony of painted storks at Kumana villu is one of the oldest known colonies in the island. Mangrove vegetation located in the middle of the villu provides ideal conditions for nesting not only for painted storks, but also for Black headed Ibises, Spoonbills, herons, egrets and even for the globally threatened Spot billed Pelicans.

A survey was done in the month of July to assess breeding status of the Pained Storks in this villu. The survey was land based where three mangrove vegetation patches (5000m2) were surveyed using a spotting scope (Nikon Fieldscope). First, all trees in each patches that contain painted stork nests were identified. Then number of nests on each tree, number of adults, hatchlings and fledglings on nests were recorded.

A total of 222 nests of painted storks were recorded. This comprised of 217 active nests of which 74 contained hatchlings while 133 nests contained fledglings. Average number of nests per tree was 3.13 while the number of nests per tree ranged from 1 to 10. Average hatchling size was 1.81 while average fledgling size was 1.78 where 61.35% nests contained 2 hatchlings or fledglings while 29.95% nests contained only one hatchling or fledgling. The nest height ranged from 1 to 10m with average nest height being 3.0m.

According to the available literature the breeding season of painted storks is from December to May. However, during this survey it was discovered that 98% of the nests were active as late as July indicating that there can be great deal of variation in the breeding strategies of painted storks. Furthermore, based on our studies we have estimated that there can be approximately thousand breeding pairs of painted storks in Kumana villu, making this one of the most important breeding sites for this species. Therefore this site should be continuously monitored in order to better understand the breeding behavior of painted storks.