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Possible
Asian House Martins Delichon dasypus in
Northern Israel
Part 1 On 23rd August 2003 Rami Lindroos, Paavo Sallinen and I were leaving Tirat Zevi reservoir in the Bet Shean Valley in the heat of midday when we decided to briefly check a flock of perched hirundines composed mainly of Barn Swallows (Hirundo rustica) of the local subspecies 'transitiva'. Amongst them was a much smaller bird, similar in size to Sand Martin (Ripraria riparia) and a debate ensued over its identity. I was sure that I could see an off white rump, eliminating everything except House Martin (Delichon urbica) or something very similar to that species. The bird's proportions looked odd, and it appeared short-tailed with the folded primaries clearly projecting beyond the tail at rest, the tail appeared to be less deeply forked than expected for a normal House Martin. Other odd features included a strange grey cast to the rump, dull greyish throat and upperbreast, and dull blue-grey mantle contrasting with rather brown, worn remiges and retrices. The views were good, but before I could take any digiscope images the whole flock flew from the wires and began aerial feeding. RL and PS both agreed that the bird looked very interesting with a number of unfamiliar features for the nominate D.u.urbica. Finding the mystery bird in flight proved quite easy since it was still early in the season for the migration of large numbers of House Martins. Moreover, the bird possessed a suit of distinctive characters including dusky grey throat, breast and flanks, and especially on the undertail coverts. The underwing coverts were distinctively dark brown/blackish and therefore darker than the brown remiges and the rest of the underparts. The superficial appearance was similar to that of Rock Martin (Hirundo fuligula) from below but it was clearly a House Martin type when the upperparts could be seen well, displaying the grey-white rump. Some of these features, especially the underwing pattern and undertail coverts, didn't register as being familiar for House Martin D. u. urbica, the only sub-species which we knew to occur in the region. The nominate D.u.urbica should apparently always show whitish or grey-white underwing coverts, and always lighter than the remiges. On returning to the lodge at Kefar Ruppin, we downloaded a number of images that were taken at the scene. The quality was not high due to the difficulties of photographing flying hirundines, but I managed to grab some interesting shots of these distinctive martins. Consultation with the 'Birds of the India' (Inskipp et al 1999) revealed that of the three House Martins occurring in Asia, only Asian House Martin (Delichon dasypus) and Nepal House Martin (Delichon nipalensis) should show significantly dark, blackish underwing coverts. Nepal House Martin could be ruled out on shape, the absence of a black throat and jet black undertail coverts, as well as a square-cut tail. We've been unable to find any contradictory information to suggest that any form of Northern House Martin could show such dark underwing coverts. In addition, some structural features including a rather shallow fork in the tail were noted, as well as all the birds appearing rather small and short-tailed.
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