In the Top End size range for male Brown Goshawk is 33-42 cm while for
Collared Sparrowhawk it's 30-40 cm (both genders). These measurements are
from specimens held at the MAGNT.
Regards
Denise Lawungkurr Goodfellow
1/7 Songlark Street,
Bakewell, NT 0832
043 8650 835
On 12/1/13 3:46 PM, "Philip Veerman" <> wrote:
> Many of these bird species mentioned are entirely unknown to me and I'm not
> going to try to find all of them in books but I will at least guess that for
> many of them they are hard to identify because they are closely related, as
> in have not diverged much, in which case there is no mystery about it. Also
> mostly they are still almost the same in morphology and size (which the C.
> Sparrowhawk & B. Goshawk certainly are not). There will of course be
> variants in things like bill length among otherwise similar hummingbirds.
> Also I would guess that for many of them it is the young, female and
> non-breeding plumages that are similar. With often the breeding males (the
> ones with the signalling functions) are often very distinct. So these are
> mostly different situations to what I was asking. Besides, my question was
> not about birds that are difficult to identify (that is not very
> interesting) but about why these two species show the same plumage pattern.
> As in I am not at all asking about our human perception, although some may
> see that there could be an element of circular reasoning in that.
>
> Philip
>
> -----Original Message-----From: David Adams Sent:
> Saturday, 12 January 2013 3:31 PM
> To: COG line; Birding-Aus Subject: [canberrabirds] Re: [Birding-Aus]
> [canberrabirds] Why are the C. Sparrowhawk & B. Goshawk so similar?
>
>
>
>> One minor point (I am also a Northern Hemispherian): Which birds are so
>> difficult to identify in Europe and North America? Apart from maybe some
>> Empidonax in North America and maybe some Phylloscopus, Acrocephalus and
>> Hippolais in Eurasia/Africa I can't think of many species that are that
> hard
>> to ID there. "Hard" birds are certainly not the norm there.
>
> Fair comment. I guess confusing is in the eye of the beholder ;-) Empidonax
> are hard, for sure...I'd list some of the other tyrants as tough, depending
> on how far afield you go. Apart from hawks, terns, gulls, pelagic species,
> and shorebirds, I'd also say that in the New World there are hard pairs of
> hummingbirds, alcids, flycatchers, ducks (e.g. Scaup), some of the New World
> blackbirds, and New World warblers. And vireos...and plenty of young/female
> tanagers. And sparrows...and finches. It's fair to say that corvids are
> probably harder here. (Unless you accept that they should all be lumped into
> C. indistinctus, as proposed last year...) Even some of the loons Old World
> warblers are tough in Europe.
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