Johnny Wee was at Singapore’s Lorong Halus recently observing a family of Little Terns (Sterna albifrons). The adults were initially feeding their chicks with small fish that the latter swallowed without any problem. Then one day he observed that the chicks were being fed with extra large fish (above). These the chicks were unable to swallow and after about five minutes of trying, left the fish on the ground (below).
The adults left the nesting area, leaving the chicks without food. True to Johnny’s suspicion, the chicks fledged the next morning, following the adults into the water to look for small fishes.
Chicks that nest in cavities and in nests that are placed above the ground are induced to leave the nests when the adults refrain from feeding them. Can it be that such a strategy does not work when nesting in a simple scrape of a nest on the ground? And that the intentional feeding of big fish that the chicks are not able to handle, a strategy to encourage the latter to leave the nest to forage?
Johnny Wee
Singapore
July 2011
