Part 3 - Possible Asian House Martins in Northern Israel.
Some comments on this fascinating subject from Paul J. Leader.
Paul Leader is an expert on Asian species and recently co-authored a ground breaking article on the identification of Pintail and Swinhoe's Snipe in the journal British Birds, (Volume 96, Number 4, April 2003). He has very kindly commented on the images and on the possibility of Asian House Martins recently suspected in the Bet Shean Valley, Northern Israel.
Paul has commented in a couple of emails as follows:
"Regarding the possible Asian House Martins. They do not fit my experience of AHM (a bird I am very familiar with as a passage migrant in Hong Kong, and on the breeding grounds in South and West China). I do not think that the structure is correct as the tail is too long and too deeply forked. In addition the lack of black below the bill is a big problem. There should also be a grey wash across the breast contrasting with a white throat.
I agree that they look very odd, but I was wondering if they are first-summer Northern House Martins and look structurally odd due to the heavy wear? "
Paul further commented:
" James,
Thanks for your reply. I am more than happy to go into more detail.
I have seen all three taxa of Asian House Martin: 'cashmiriensis' in Qinghai and Sichuan, 'nigrimentalis' in Hong Kong, Guangdong and Fujian, and 'dasypus' in North East China and Hong Kong. In addition I have trapped both 'nigrimentalis' and 'dasypus' in Hong Kong. I have also seen many Northern House Martins including 'lagopoda' in North West China.
The three taxa of AHM are all quite similar in the field (although the vocal differences are quite interesting), and I have found 'D.u.lagopoda' more similar to British birds (Northern House Martins) than the literature suggests. Structurally Northern House Martin (including 'D. u. lagopoda') is strikingly different to all three taxa of Asian House Martin. The tail is extremely long and deeply forked. It may also be that the body is longer, as I don't think the published differences in tail length quite account for the difference. I would say that on a bird in flight, the distance from the base of the wings to the tail tip is (at least) 25% longer in Northern House Martin (it would be good to try and measure this from photos).
Plumage differences are well covered in the literature and I covered those in my last email. Rump size and dark under wing coverts are both very good, obvious field marks. I think that at least one of your photos (photo 'a' in Part 1) has too large a white rump for Asian House Martin. Also the lack of black below the bill on the good perched photo (Part 2) is a major problem (although not having trapped 'cahmiriensis', I am not sure if this feature applies to that taxa as well - perhaps this can be checked from skins).
Having looked again at your photos it seems clear that most (if not all) are of first-summer birds (one is even in suspended moult, which I would have thought could only fit a first summer bird?), which is perhaps partly why they appear odd (I don't ever recall seeing or trapping a first summer Northern House Martin in the UK, but that was a while ago!). The other possibility is that they are 'lagopoda' (subspecies of Northern House Martin).
However, unless 'cashmiriensis' has a dramatic clinal variation (I have only seen it at the extreme eastern end of its' range) I am sure that based on my experience of Asian House Martin your photos do not fit that species.
One other thing - did they call? I'm not good at transcribing calls, but they are very different.
I hope this helps.
Best wishes,
Paul
Director Asia Ecological Consultants Ltd. New Territories, Hong Kong.
We would like to thank Paul for his expert opinion. Given Paul's extensive experience it would appear, despite the odd appearance of the Bet Shean Valley House Martins, that there's little room for argument and that these birds are not Asian House Martins. Unfortunately, the odd martins were not heard, so we can't add any comment to Paul's final question.
On the other hand, it's been a fascinating encounter with what appears to be a poorly known, and poorly described plumage (ie. worn first summer?) of Northern House Martin. Rami, Paavo and myself are still puzzled by the odd appearance of these birds and will continue to explore the subject.
Here's a reflection of three of the most interesting images.
Good birding,
James P. Smith and the Birding Israel Team
Contact info
Daphna Abell
Program Coordinator
lotan-programs@lotan.ardom.co.il
Tel: +972 8 6356935;
Toll Free: 1800 2000 75 (when in Israel)
