Hello Steve,
Thanks for showing an interest in ravens in W.A. etc.
It's a while since I lived there (left WA in 1984) so my memory for the details
is not perfect.
So far as I (and anybody) know, nominate coronoides doesn't occur in W.A., but
the Nullarbor is the key. Along with mellori, c. coronoides occurs as far as
the cleared farming country in S.A. that is somewhere about Penong.
The common corvid across the Nullarbor Plain is bennetti but ravens do occur
closer to the coast, about as far east as Eucla. - which ones is an interesting
point, there are few specimens. The differences in specimens of perplexus and
coronoides are not great, and when you take sexes and juveniles into account,
it would need a good sample from the Nullarbor region and western S.A. to sort
out what is the case.
I wouldn't pay too much notice to the "data" in the BA Atlas - Corvids are
probably the most mis-identified group in Australia - even the latest article
in Australian Birdlife (Wingspan) has a few errors.
I feel confident that as soon as you reach Kalgoorlie, all the ravens would be
perplexus. Heading north from Perth, ravens are replaced by Torresian Crows at
the mulga/eucalypt line, on the coast road about 150 km north of Geraldton.
I assume you don't have access to Schodde and Mason's DIRECTORY (few people do,
mores the pity - they only printed 1000 copies) so I am attaching copies of the
relevant pages for coronoides.
Whether the Western Raven merits specific status is far from settled, otherwise
it would have been done already. DNA is not the final word.
I hope this has been more help than hindrance.
Regards
Graeme
On 22/06/2012, at 9:38 AM, Steve Clark wrote:
> G'day Graeme
>
> Thanks for your thoughts and reference to your site with calls.
>
> Are you suggesting that the 'Western' Raven is confined to the
> south-west corner and the birds elsewhere in WA are nominate
> coronoides? Looking at the BA atlas data in Birdata there doesn't
> seem to be a gap along Highway 1 across the Nullabor. Corvids are
> tricky however so how many of the dots are C. coronoides and how many
> are C. bennetti? I must check my own records from our trip across in
> 1999 when I get home tonight. From memory we allocated many to C.
> bennetti (but I've learned to put less trust in my memory these days).
>
> So, as you drive west and head into sw WA where do you think the
> 'Western' Raven first appears? What about heading north from Perth?
>
> Cheers
> Steve
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