I concur with Geoffrey on the tail issue. I have the pleasure of seeing
both species reasonably frequently up at the Pinnacle, and I've found
the tail of the perched bird to often be deceptive.
In Julian's photo, the only clearly definitive element to my eye is the
elongated middle toes. I agree with Julian that both toes look unusually
long given the positions of the legs. On a more subjective (dodgier)
note, my immediate first impression of the photo was that it was a
Sparrowhawk -- I think due to the less "massive" impression it gives.
Goshawks always seem to me to look generally more hefty somehow. All
very subjective, of course.
John Brannan
On 30/12/10 2:03 PM, Geoffrey Dabb wrote:
To be unambiguous the tail needs to be slightly spread so you can see
all the feathers, preferably fresh and full-grown ones.
How about it is paired with a mate that is either very large or very
small? This could involve a bit of a wait, though. g
*From:*Julian Robinson
*Sent:* Thursday, 30 December 2010 1:11 PM
*To:*
*Subject:* RE: [canberrabirds] Chestnut ID opinions please - Sparrowhawk
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.
from [/Julian Robinson/
<http://bioacoustics.cse.unsw.edu.au/archives/cgi-bin/namazu.cgi?query=%2Bfrom%3Ajulian.robinson%40internode.on.net&idxname=canberrabirds&sort=date%3Alate>]
[Permanent Link
<http://bioacoustics.cse.unsw.edu.au/archives/cgi-bin/mesg.cgi?a=canberrabirds&i=77b3rb%245pkdlc%40ipmail01.adl6.internode.on.net>][Original
<http://bioacoustics.cse.unsw.edu.au/archives/cgi-bin/extract-mesg.cgi?a=canberrabirds&m=2008-09&i=77b3rb%245pkdlc%40ipmail01.adl6.internode.on.net>]
*To: *
<
<>>
*Subject: *
Re: Goshawk or Sparrowhawk??
*From: *
Julian Robinson <
<>>
*Date: *
Wed, 17 Sep 2008 10:56:42 +1000
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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