These photos were taken at Mae Hia Agricultural College on 27 August 2013. I was trying to get some photos of a brilliantly coloured female Greater Painted Snipe but failed as usual. There was, however, a pair of Collocalia swiftlets coming down to drink water from the flooded fields where the painted snipe was staying. I managed to get some record shots which I think might be useful as references for future ID on this group.
Note the distinct greenish gloss on upper wing coverts, a characteristic of birds in fresh plumage. Interestingly, the rump patch seems to be strikingly pale, similar to Germain’s Swiftlet. This individual has a pretty full crop.
Another bird with an empty crop. The greenish gloss is also presented but the rump patch seems to be less contrasting.
Another shot of the same bird. Note the greenish gloss and pale but not strikingly contrasting rump patch.
Here’s the underparts of the empty-cropped bird.
And here’s the underparts of the bird with full crop.
My guess is that these are the race ‘rogersi’ of Himalayan Swiftlet or Indochinese Swiftlet as split by some authors, according to the distribution range, date and behaviour. From what I observed, I assumed that they were a breeding pair and ‘rogersi’ is said to be the only resident member of ‘Himalayan Swiftlet Complex’ in NW Thailand. However, it’s probably impossible to be sure if they really are ‘rogersi’, but at least these photos serve as the evidence and reference for Collocalia swiftlets found in the plains of NW Thailand.
The drinking show ended with something way less confusing, an Asian Palm Swift.
Unmistakable with long and pointed wings and tail. It was the first time for me to notice their slight greenish gloss on the upper wing coverts and upper tail though.