Sumit said:
Thanks Dave. That was very useful. I have, like many others who have responded, wide experience with Yellow and limited experience with Little. It would be nice if members who have experience with Little comment on the likelihood of the bird being of that species. Colour is affected by lighting, but even then I would normally expect a male Little to have much darker mantle and scapulars. As you can see from the attached, this Yellow almost matches the shade of Cyberdoc's bird.
I am seriously interested in eliminating Yellow because that could raise all kinds of range related discussions. The Little is at home where the pic was shot.
Cheers!
Sumit
Hi Sumit,
This may be a can of worms, but it is a very educational one!
I don't have any literature to hand that compares
minutus to
sinensis , so perhaps there are known distinguishing features that I am not aware of.
The only resource I have access to is the net. From some googling, I have found that the culmen colour does not appear to be a useful distinguishing feature, and I have found nothing conclusive regarding the thickness of the base of the bill.
Light is, as you say, a powerful influence affecting apparent colour. Your excellent picture is taken slightly into the sun, so I would expect the back colour to look darker than in neutral conditions. (The copy of the same image in the Oriental Bird Image database looks slightly less contrasty). On the other hand, CyberDoc's pics are in full direct sunlight, thus possibly making the back appear paler than in neutral conditions.
One feature that I have noticed in my google search is the tertial and inner greater covert colour. On
minutus this appears to be very dark, contrasting strongly with the rest of the wing coverts, whereas on
sinensis, though they may be slightly darker and warmer than the rest of the wing coverts, there is never a strong contrast such as on
minutus . Your picture is a good example of this difference, when compared with CyberDoc's pics.
So, I am still tentatively of the opinion that CyberDoc's bird is
minutus , but like you, would like to hear from others more familiar with that species.
Does anyone else know how to differentiate Little and Yellow Bitterns, especially when not in adult breeding plumage and when not in range?
An intriguing puzzle!
Dave