Facts:
“On 25th February 2010 at 10:30 hours I was bicycling along Mandai Road and saw what looked to be two birds flapping on the ground up ahead next to the track. This is a wooded stretch with large trees and branches hanging over the trail. I could see wings beating in the leaf litter; I mistook the event for two birds fighting on the ground. When I slowly got closer to investigate I saw a brown animal with a reddish head curled around a bird and holding it down. The long tail was wrapped around it like a snake. As I got too close, the animal released its grip and scuttled into the woods, I could see it was a male Changeable Lizard (Calotes versicolor).

“This lizard occurs naturally on the Indian subcontinent, south-east into Thailand and northern Peninsular Malaysia. It is believed to be introduced into Singapore, where it is now common. It feeds on insects and even small lizards according to Baker & Lim (2008).

“When I looked at the bird I saw it was a female Pink-necked Green Pigeon (Treron vernans) (left top). It was gasping for air, the tail was bent backwards against its back. There were no visible wounds except a bite-mark on the back of the head (left bottom).

“According to Wells (1999): “Like other green pigeons (the Pick-necked Green Pigeon), hardly ever descends to the ground.”

I returned to the site again 2½ hours later with a camera. The pigeon had died and was being attacked by ants. There was no sign of the lizard.”

Speculation:
“Most likely the lizard attacked the pigeon on a branch in the tree above the trail and they fell to the ground. The flapping I saw was the pigeon trying to take off again. The puncture wound on the head was enough to kill the pigeon, but the lizard never returned to feed on its prey.

“It would be interesting to know if there are other cases of this invasive lizard species predating on birds.”

References:
1. Baker, N. & Lim, K. (2008) Wild Animals of Singapore. Draco Publishing, Singapore.
2. Wells, D. R. (1999) The Birds of the Thai-Malay Peninsula. Volume One. Christopher Helm, London.

Howard Banwell sent in a photo sequence of a female Pink-necked Green Pigeon (Treron vernans) swallowing fruits of the MacArthur Palm (Ptychospermum macarthurii) taken at Singapore’s Seletar Air Base on 15th February 2010.

“We watched her and her mate eating numerous fruits one after the other, but no sign of regurgitation of the seed or skin,” wrote Howard.

An earlier post shows the male Pink-necked Green Pigeon swallowing the same fruit. However, the current post shows the complete sequence of swallowing.

Yellow-vented Bulbul (Pycnonotus goiavier), which has a smaller gape than the pigeon, similarly swallows the fruit whole. Details of the fruit in cross-section showing the pulp and seed can be seen HERE.

It is very possible that the seeds may be passed out after going through the digestive system, as it is relatively small compared to the size of the fruit. But we have yet to be fully convinced that the seeds are not subsequently regurgitated.

Willi Kwek photographed a fly running around the body of the fledgling Spotted Dove (Streptopelia chinensis). “This fly, also seen on the other doves, appears to have special adaptations on its feet for holding onto feathers,” says Willi. “It also has a flat profile for easy burrowing through the feathers. It appears to irritate the dove, who would try to peck at it or to preen it off, but the fly is too quick. It darts all over the bird’s body, burrowing in and out, and it’s difficult to predict where or when it would next reappear on the surface. Thought your biology or ornithology friends might be interested. Took these photo with my kit lens so not so detailed.”

According to Dr Leong Tzi Ming, “The parasitic fly on the Spotted Dove is most likely to be the cosmopolitan Louse Fly, Pseudolynchia canariensis (Order Diptera: family Hippoboscidae: subfamily Ornithomyinae). It is a highly evolved, obligate ecto-parasite of birds, with a dorso-ventrally flattened body designed to slide in between feathers with ease. It also has robust limbs with strong claws, that aid in hanging on to a rapidly flying host. In Singapore, this parasitic fly has been recorded from Feral Pigeons (Columba livia), and is itself a vector for the hematozoan endoparasite, Haemoproteus columbae (Paperna & Smallridge, 2002). The Louse Fly has also been reported on many other avian hosts, including the Malayan Red Jungle Fowl (Gallus gallus spadiceus) (Lee & Amin-Babjee, 1993).

Image by Willi Kwek.

References:
1. Lee, C. C. & S. M. Amin-Babjee, 1993. New host records of parasites in the Malayan Red Jungle Fowl, Gallus gallus spadiceus. Pertanika J. Trop. Agric. Sci., 16(2): 107-110.
2. Paperna, I. & C. Smallridge, 2002. Haemoproteus columbae infection of feral pigeons in Singapore and Israel. Raffles Bull. Zool., 50(2): 281-286.

“Birds flock and roost together for many reasons. One reason I can think of is that as a collective unit, they are more alert with many pair of eyes that are able to look at different directions. Thus, the probability of spotting a predator will be increased significantly.

“A flock of birds consisting of Pink-necked Green Pigeons (Treron vernans) and Asian Glossy Starlings (Aplonis panayensis) was roosting peacefully in a tree one early morning (above). Suddenly, the birds screeched and took flight. Collectively, the birds must have spotted a predator and took evasive action. Sensing danger, the birds were reacting instantaneously. In a split second, all the birds were in the sky and the tree was barren of birds.

“The evasive action took less than two seconds. It was interesting to note that the fastest and first to react were the Asian Glossy Starlings. The Pink-necked Green Pigeons were noticeably slower in taking flight. What spooked the birds? No, it was not a bird of prey or raptor. It was a pair of Oriental Pied Hornbills (Anthracoceros albirostris) flying above (below left).

“The pigeons and starlings were probably alarmed by the large, odd looking hornbills, probably mistaking them for predators. The hornbills were later seen sharing the same tree. However, the smaller birds accorded due respect to the hornbills by perching on the opposite branches of the dead tree (above right).

“The hornbills did not bother the smaller birds but were indulging in preening and allopreening (below). 

It was observed that the female joined the male on the branch and initiated allopreening. There were occasions when she reached below the branch to delicately touch the male’s tail feathers, which she later raised with her bills and preened. Is this part of courtship behaviour?



“I believe that this pair of hornbills have made Pasir Ris Park their home and may be prospecting for a nest. I have spotted the couple on at least three different days over the past fortnight. 

To the officials of National Parks Board, please watch out for the hornbills at Pasir Ris Park when carrying out tree maintenance. The oriental pied hornbills, first originating from Pulau Ubin, then moved to Changi, could have started their highly awaited propagation on mainland Singapore.

 Lets all do our part to help conserve this majestic birds.

”

Kwong Wai Chong
Singapore
16th December 2009

According to Lim Poh Bee, there have been many reports of different species of birds including the Pink-necked Green Pigeon (Treron vernans) feasting on the seeds of the yellow simpoh air (Dillenia suffruticosa) (1, 2 and 3).

“But in early November 2009 I observed a pair of Pink-necked Green Pigeons at Bukit Batok Nature Park picking the yellow petals of the simpoh air flowers and swallowing them. It was a surprising sight,” recounts Poh Bee.

“The actions were very fast but were repeated several times. After all the petals from one flower were finished, the pigeons would go to another flower and consumed the petals from there too. As can be seen from the image attached, the birds seemed to be enjoying themselves. The petals must have been very delicious morsels.”

An earlier post shows the Red-whiskered Bulbul (Pycnonotus jocosus) eating the flowers of the starfruit tree (Averrhoa carambola).