No one has come forward with suggestions to House Swift ID so I will
give it a go. I am not an expert on House Swifts, having only had a very
brief view of a small flock some years ago. I spoke to a few people here
in N. Qld who have seen House Swifts well over the years and we have
come up with the following.
Firstly, I should add that the Australian field guides are really of no
help at all with either House Swift or White-rumped Swiftlet - more
misleading than helpful. All have missed the important points.
House Swift - Much more compact than Fork-tailed Swift, more like a
woodswallow - (some say it is very reminiscent of a gliding
White-breasted Woodswallow). White rump and throat patches are obvious.
The tail appears heavy at base. Not as long-winged as other swifts and
wings are not sickle-shaped - rather shorter and blunt at the tips. It
is unhurried compared to other swifts and tends to glide much more than
Fork-tailed. Not as fast - glides in circles - doesn't fly directly away
but drifts away in an unhurried manner.
- Also a few random notes from Swifts - A Guide to the Swifts and
Treeswifts of the World (Chantler and Driessens) and Collins Bird Guide
(Mullarney et al.) -
"Fork-tailed is much larger than House Swift, longer-winged, longer
tailed and more powerful and has a very different jizz. Several swiftlet
species have pale rumps but none are as striking as that of House Swift.
Underparts of Fork-tailed appear greyish when viewed in sunlight at a
distance but scaly plumage is only visible at close quarters. Quite
broad rump patch of House extends onto the flanks and so can be seen
from below. Within its range, the combination of white rump and
shallowly forked tail are diagnostic".
One important thing would be to recognise moulting Fork-tailed Swifts
when a strange swift is seen (re: my previous posting - notes by David
James).
White-rumped Swiftlet - All of the field guides miss the most important
feature which immediately separates the species from the Swifts and
Needletail here in Australia - the blunt, wings held stiffly at a
downward angle in gliding flight which is distinctive. The field guides
mostly depict the swiftlet with long pointed wings - a mirrored image of
the larger swifts. Slater's is closest to wingshape but he still does
not depict the typical downward angle. For a good example of this
wingshape, see the illustration of Mountain Swiftlet in Chantler and
Driessens. (There is always the extremely remote possibility of one of
the all dark New Guinea swiftlets (eg Uniform or Mountain) which
apparently have a similar wingshape turning up - probably more so in
northern Cape York and Torres Strait but none of us who regularly
scrutinise WRS flocks in N. Qld have seen anything different).
Thanks to Glenn Holmes and Del Richards for input in getting this
together.
Hope it is of some help
Lloyd Nielsen
Mt Molloy Nth Qld
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