A comprehensive survey on heronries has identified 10,380 nests of waterbirds from 157 sites across the State.
Birders recorded 44 heronries and 2,586 nests from Palakkad, the highest in the State. Malappuram had 25 heronries and 1,826 nests followed by Kannur (24 heronries and 1,302 nests), the report said.
Heronries are the communal nesting places of large waterbirds. Mixed species heronries could be seen as different species breed at the same place. Kerala has about 15 species of resident and breeding waterbirds nesting in various heronries.
Painted Stork, one of the three rarest breeding waterbirds of Kerala, was found nesting only at Kumarakom heronry. The other two species, Grey Heron was found nesting at Koduvally near Thalassery and Eastern Cattle Egret breeds at Panamaram in Wayanad. The heronries at Kumarakom, which has 12 species of birds breeding, and the one at Panamaram with 10 species were the two prominent ones in the State.
Though Woolly-necked Stork is known to breed in Kerala, it does not breed in the colonial heronries here, the survey report prepared by a team led by noted ornithologist C. Sashikumar for the State Forest Department pointed out.
Ornithologists say that protection of heronries is important for the conservation and management of the bird species. These birds are integral part of the agricultural ecosystem and have a role in pest control and enhancing nutrients.
Most of the heronries were found located on government land and on roadside trees. Many trees located at busy market places, bus stands, railway station compounds and places where people congregate were used by the birds.
In Kochi, heronries could not be identified during the survey.
The heronries in Kerala become active since May, prior to the onset on southwest monsoon and breeding will continue till October. The two months from July is considered as the peak breeding season, the report pointed out.
Conflicts
Heronries often find themselves in conflict with local population due to the annoyance caused by the cacophony of nesting birds and the food-begging nestlings. The nuisance caused by bird droppings and fallen food items often provoke action against the nesting birds. People often drive birds away. There have also been instances of killing of birds for meat. Cutting of roadside trees too is a matter of concern, according to ornithologists.
Ornithologists have come up with heronry guards, a metal structure which could be fixed on the trees to collect droppings. Planting of trees at near wetlands and paddy fields with the cooperation of farmers have been mooted. These sites would also serve as tourist attraction with assured sighting of a few species, said an ornithologist.
