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I'd
say it is 90%+ certainly a Collared Sparrowhawk. There is enough to go on in
several features, the toes, the slim appearance, the small eye ridge, Quite
apart from the other things mentioned, the beak is small relative to the head. I
haven't looked at museum specimens about this to check on this but given a close
view (or a close photo!) I think that is a diagnostic and consistent but small
difference. The tail is not quite in focus (though it is still a excellent
picture). I'd call it a CS based on the tail too. When tight closed like
this on a BG it should be obvious that the outer feathers are much shorter than
the inner ones. Here they appear to be close to the same length, even though it
is a bit of a guess and the tips are not really clear. When that tail is spread
it should clearly be straight edged to slightly forked in appearance. (Maybe
apart from when in moult) the BG tail appears well rounded whether closed or
open.
I had
very close long look at a very nice female Collared Sparrowhawk in my
garden yesterday, it stayed around for over an hour (upsetting the Ravens). I
was noticing the tail shape just as in this picture.
About
"giss/jiz (how do
you spell it?)," David McDonald wrote an interesting (even off beat)
etymology of the word "jizz" in CBN some years ago. And their calls are very
similar too.
Your message below talks about a bird as a Brown Goshawk but I am a
bit lost. I think that is referring to another bird at another time.
What
is "Chestnut ID"?
Philip
Thanks Geoffrey for the reminder
of previous discussion. I am still hoping for some discussion/resolution
of this particular bird (especially the tail shape of which I really don’t
understand what people and books say). The reason I was hoping for a
definitive call from someone who can latch onto some unambiguous diagnostic was
because I want to submit it to an interesting flickr group to which I
contribute. This group has gone a long way towards being a useful
photographic field guide of birds of the world. It uses the collective
power of zillions of photographers (actually ~12,000) to build up a number of
hopefully representative shots of each bird. At this stage they have just
on 100,000 photos of over 7,000 species, which teamed with a working index and
the fact that photos have location info attached makes a pretty useful database
that COGers might like to add to their reference resources.
http://www.flickr.com/groups/birdguide/discuss/72157594382295215/#comment72157594382316800
Julian
From: Geoffrey
Dabb [
Sent: 30 December 2010
11:30
To:
Subject: FW:
[canberrabirds] Chestnut ID opinions please -
Sparrowhawk
For those who came in later, I
reproduce below from the archive Julian’s summary of a previous ‘Which hawk is
this?’. This will save some repetition.
I would add a further thought
that has occurred to me. Not only is the male goshawk similar in size to
the female sparrowhawk, but other characters are similar as well, eg thinnish
toes and a less strong bill. It is the FEMALE goshawk that has the heavily
scowling brow, less pronounced in the male goshawk. Below I have taken the
liberty of placing Julian’s photo between 2 snaps of a certified male
goshawk. Similarities are evident. So far as I’m concerned Julian’s
bird could be either, but I’d lean slightly to a female sparrowhawk for reasons
given by Julian.
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Thanks
to those who answered this post. Here's a summary of responses which
were very educational, not so much about the actual identity of the bird,
but the take-home messages for me as a bird photographer. Which have
been said many times before but still ...
- identifying difficult
birds from a single view or a photo can be hard or impossible.
Without call, giss/jiz (how do you spell it?), or alternate viewpoints
half the information is missing, and lighting in a single view can add
great confusion by changing colours and giving false impressions of
dark/light patches, or losing or overly emphasising some
characteristic. (On the other hand a photo does have the advantage
that it exists in front of the puzzled observer for ever to allow detailed
comparison with guides and books, unlike an ephemeral field sighting which
can be contaminated by later thoughts and inputs).
- birders have
to make calls on identifying between similar birds but there is often
plenty of room for doubt despite how certain we can be as individuals
(something which must make the work of the rarities panel quite
difficult).
- even obvious things like "long toes" can mean
very different things to different people and have to be used with
caution.
Below's extracts of responses, some of which were in
another conversation of which I was unaware until later. With the
exception of Philip's informative post to the chatline, I've anonymised
them to remove possible embarrassment although no embarrassment would be
called for. I doubt we will ever know for sure since later sightings
might not be the same bird. As far as I know all responders are
knowledgeable birders, some extremely so.
For what it's worth I'm
going back to my original call, which was Goshawk knowing this goes
against opinions of some vastly better birders than me. I didn't
really see the bird other than in the photographed
location.
------------------------------------------------
Don?t
worry about being confused xxx, beyond an obvious female Goshawk or male
Sparrow-hawk, the in between zone is much more difficult than people would
have you believe especially when trying to work from photos as apposed to
seeing the bird in the flesh.
If
ever I've seen an obvious photo of a Goshawk that is it. Tail shape, feet,
eye ridge, beak size........
I vote for immature Collared
Sparrowhawk going by the stare which strikes me as "wide eyed" rather than
the "heavily hooded" glare of a Brown Goshawk.
I would put my
bet on your bird being a Brown Goshawk.
I?d say pretty certainly a
sparrowhawk, given the very clear view of the diagnostic toes. ... While
the sparrowhawk does not have the scowling brow, it does have a little
ridge above the eye that does not overbear it ... The tail is in moult so
not that much help.
For
what its worth, and based on things like the G Dabb ID lessons, I reckon
it?s a Goshawk. It has a bit of a cranky look, and the middle toe
really isn?t very long compared to some of the winkle-pickers I have seen
in photos of Sparrowhawks.
I
was looking at your hawk shots from Callum Brae, and based on the long
middle toes and skinny shanks I think they are Collared Sparrowhawks.
I
reckon that the ... photo... show a male Brown Goshawk. I'd argue that the
middle toe is too short and thick for Collared Sparrowhawk, that the
brow-ridge is typical for Brown Goshawk and too heavy for a sparrowhawk,
that the tarsus is a bit too stout for a Collared Sparrowhawk, and that
the tail shape (funny though it is) can only fit Brown Gos.
The
tail of the... bird could be moulting, and I suspect that t2 and t3 are
growing, not full length; t1 seems to be retained juvenile, t6 is probably
first basic. (It was) reported a few years ago that in Brown Gos, the tail
of juvs is slighlty longer than that of adults. I looked for this effect
in Collared Sparrowhawk and couldn't find it. Maybe I should look again -
if it's only Brown Gos in which juv tail is longer than ad tail, then
there might be a new ID feature to work with on moulting
birds.
I
must admit when I saw ...the photos I thought, sparrowhawk... |
From: Julian
Robinson [
Sent: Thursday, 30
December 2010 8:21 AM
To: canberrabirds chatline
Subject:
[canberrabirds] Chestnut ID opinions please -
Sparrowhawk
I know this has been discussed many times, but I would value
opinions on this Sparrow / Gos hawk. I have no further info to add
to the photo except the immediately preceding circumstances – in a small
clearing amongst pines near Gundaroo this bird rocketed in carrying prey.
It was intercepted by another just out of view in pine trees, some carry on then
the other bird disappeared and this one reappeared on the branch without the
prey. I assume this parent was feeding its young. The photo is more
informative than the view I could make out with bins in the gloomy recesses of
the pines.
I’m calling it a Sparrowhawk because of the non-heavy brow
ridge and somewhat staring look. Supporting this could be the centre toe
which seems very long given that you can see the front of the centre toe but not
even the nail of the other toes, and also it seems a long way from where the
extended left leg would meet the branch. Counting against
sparrowhawk according to my reading is the shape of the tail feathers, but I’ve
never really worked out what you are looking for in closed position, and some
say that this is an unreliable diagnostic clue.
I would appreciate any educational info and any decisive
ID.
Julian
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