“January 2011 must be an auspicious month for birders and photographers. The appearance of some uncommon and rare birds generated great interest and excitement. The hot spot was at Pasir Ris Park where more than a handful species of cuckoos suddenly appeared. Species spotted from mid January included the Large Hawk-Cuckoo, Hodgson’s Hawk-Cuckoo, Violet Cuckoo, Asian Drongo-cuckoo, Indian Cuckoo and Little Bronze Cuckoo. Many birders and photographers congregated to whet their appetite on some of these hardly seen birds. The Violet Cuckoo (Chrysococcyx xanthorhynchus), known to be an uncommon resident breeder and winter visitor, was probably the favourite of most photographed due to its attractive plumage and its willingness to be seen.
“This male Violet Cuckoo appeared to have a preference for a cluster of trees that was relatively bare of foliage in the middle of the park (left). The defoliation, I suspect, must be due to the hosting of unidentified caterpillars. Although difficult to spot, these caterpillars did not escape the sharp eyes of the Violet Cuckoo. The composite image shows the sequence of the cuckoo catching a caterpillar (below). It was so adept at spotting the caterpillars that it had a meal every other five minutes. It was having a feast. The limelight was temporarily taken away from the Violet Cuckoo when a Black-naped Oriole (Oriolus chinensis) stole a caterpillar from right under the nose (or should I say beak) of the Violet Cuckoo. The cuckoo was actually nearer and within striking distance of the prey. On another occasion, the cuckoo took flight with a caterpillar in its beak after it sensed an oriole watching it (below).
“The Violet Cuckoo, true to its name, was a striking hue of violet, especially under good light that got reflected off its plumage. During good lighting condition, it was conspicuous even when framed within the maze of haphazard stems. Shaded away from light, the plumage turns dark and it will be much more difficult to spot. Aesthetics apart, this Violet Cuckoo was impressive in catching caterpillars. It had a different technique for processing the prey before consumption. Instead of the usual bashing and thrashing of preys on a perch that was commonly used by other species, its method was to swing the prey in mid air (below).
“Once a caterpillar was caught, it will be manipulated and held firmly at one end of its long and slender body. The caterpillar will be wriggling; no doubt trying to escape from being a meal. Despite its efforts, there will be no escape. Invariably, it will remain firmly in the grip of the cuckoo’s beak. The cuckoo will tilt its head to one side before twisting its head to the opposite side; causing the caterpillar to swing at great speed in the air. This will usually be done a few times. The cuckoo may manipulate the caterpillar from one end of its body to do the swing from its other end. This repeated swinging action will weaken the skin of the caterpillar; causing it to rupture and resulting in the greenish bodily fluids leaking out. The cuckoo will then raise the caterpillar above its beak before the prey disappeared into its throat.
“The Violet Cuckoo and the other cuckoos must have gone elsewhere as they were no longer seen; the Violet had not appeared since end of January. As for the cluster of trees where the Violet Cuckoo used to appear, the leaves are now growing back. I believe that the caterpillars must be gone too. I wonder whether they have turned into butterflies, moths, or had ended up as meals for the birds. “
Kwong Wai Chong
23rd February 2011