Hi Alison,
Not sure if you are joking. I think you are. However as it leads to an interesting thought I will comment. They most certainly regard themselves as different.
I wonder if they avoid each other. In all my time I have never seen two of both species in any kind of interaction, even though aggression of hawk species is otherwise common (and some are sociable). When you see the difference in sizes between the sexes and
compare between species and the importance that sexual size difference has to them, it is clear why they don’t get confused.
What is really curious though is that both the adults and juveniles of these two species are so different in their colouration by age but both so similar to
the other species. Combined with no difference in colours between sexes in both. I don’t know of another such case.
Most of this group of hawks are sort of along similar colour schemes, so their basic colouration is not odd. Around the world there are a few other species
pairs of goshawk & sparrowhawk (by various names) that live in similar places that are curiously similarly similar but I don’t think there is any example as extreme as our two species. Could there be mimicry involved? Hard to see any benefit. I have asked
the questions but no one has suggested a reason. Maybe there just isn’t one.
As for the toe lengths did you read my prior message?
Philip.
From: Alison Turner [
Sent: Wednesday, 2 December 2015 5:49 PM
To: Michael Craig
Cc: Ken Bissett;
Subject: Re: [canberrabirds] ID help please
I am really wondering if someone has the evidence that there really is two species or is it one species with variation between individuals( like humans) . I got a number of photos of " both species " last year , but on reviewing the photos
, the toe lengths were all over the place .
Alison Turner
Sent from my iPad
On 1 Dec 2015, at 10:51 pm, Michael Craig <> wrote:
Ken,
I would say this is a brown goshawk. There are 3 ways to tell them apart, none of which are particularly easy and two of them aren't visible in this photo. The first is that a goshawk has a tail that is rounded at the end whereas a sparrowhawk's is square (i.e
straight across) at the end and typically has a little notch in the middle. The second is that sparrowhawks have legs that are much more slender than goshawks (and with a longer middle toe) and you can identify them on this alone with a bit of practice. The
third way is that goshawks have a brow ridge whereas sparrowhawks don't. This means that sparrowhawks "stare" while goshawks "frown". As this beautiful bird definitely looks like he's frowning at us, I'd be confident this bird is a Brown Goshawk. Very nice
photo!!
Cheers,
Mike
From: Ken Bissett
Sent: Tuesday, December 01, 2015 5:17 PM
To:
Subject: [canberrabirds] ID help please
is this a brown goshawk or collared sparrowhawk and how to tell the difference please.
thanks
Jill/Ken
