ID help, terns and sand plovers, Phuket, Thailand, Nov 8 (1 Viewer)

[bhutjoe]

Hi, attached are rather poor photos, apologies, of what I initially thought were two greater sand plovers on the left and two little terns with a lesser sand plover between them. My identification of the lesser and greater was based on their relative size (and no white collar) while that of the terns was on their diminutive size and the black "shoulder" mark, as well as head pattern. However, in reading Robson's "Bird of SE Asia" it would seem that little terns are about the same size as greater sand plovers. Have I misunderstand how to apply the size measurement of birds? Confirmation or correction on my identification would be greatly appreciated.
Thank you in advance
steve

 

[johnallcock]

The sand plovers look like (Tibetan) Lesser, based on head/bill shape, head pattern and breast pattern. I agree that the terns look like Little.

Size from field guides can sometimes be a little misleading as it usually gives the total length of a bird, but the apparent size can depend on structure. So a long-tailed, slim bird like a tern may not look as bulky as a more 'dumpy' bird with the same length measurement. In this case, HBW gives the following measurements: GSP 20-25cm, 55-121g; LSP18-21cm, 39-110g; Little Tern 22-28cm, 47-63g. So Little Tern has the longest length measurements of the three species, but the average weight is towards the low end of the range for either of the sand plovers.

 

[bhutjoe]

Thank you, John , for clarifying what the measurements are measuring for me Much appreciated. I was thinking of height, obviously wrongly.

May I ask, do you think the taller plovers to the left are Greater Sand Plovers or is this just an optical illusion.
thanks again. very much appreciated
steve

 

[johnallcock]

I think it's an optical illusion caused by the birds standing more upright and alert. Structure and plumage looks like Lesser SP.

 

[bhutjoe]

Thanks John, very much appreciate your taking the time on these odd photos.
steve