I think if you split this one, there are a bunch of other candidates waiting to
be looked at from Tas, like the small Tas Magpie, the long shrike-like billed
Tas Grey Shrike-thrush (bills are supposed to be smaller proportionally in
higher latitudes, this has a bill at least 33% larger with no overlap;
additionally has a distinct white throat); & wait there are more......
Can you elaborate on some other potential Tasie spilts Kevin
Thanks, Michael.
> From:
> To:
> Date: Fri, 14 Jun 2013 01:34:15 +1000
> Subject: [Birding-Aus] •Possible Tasmanian Morepork in Victoria
>
> Here's my take on the subject of Tas Moreporks on the Aust. mainland.
>
> Without going into too much detail & based on my memory of 3 specimens
> collected I found dead in Victoria (1 beachwashed at Phillip Island; 1 dead
> on road near Ocean Grove & 1 up in the mountains in Camberville) & now lodged
> in the Museum of Victoria & then a comparison between these birds, a good
> collection of Tas skins, Tas-like birds collected in Vic & a large collection
> of mainland ssp all in the Vic Museum.
>
> Firstly the photograph taken at Hamilton is definitely a Tasmanian Boobook.
> This is based on bright yellow iris (dull greenish yellow in mainland
> Boobooks); small white spotting on crown (if there is any blotching on
> mainland birds it is large & cream or brown, more likely to be streaked in
> this area; certainly not white & not tiny as in this bird); the patterning
> below is finely with whitish blotches (in mainland birds this is occasionally
> blotched, but not white & usually streaked; blotches tend to be larger, or
> streaked and usually cream-coloured, although sometimes whitish); overall the
> upperparts seem very dark (this is more mid-brownish, not so dark brown in
> mainland birds). I have seen a Tas bird in Tas & it was remarkably
> small-looking & very dark with spotting on crown & blotching as described
> above.
>
> Within each subspecies (or species?) is a fair bit of variation & there are a
> few birds that may be difficult to separate in the field, but most of the
> differences hold true & I cannot find any evidence of a mainland bird which
> has the Tas Boobook characters that was collected in the summer months of the
> year. This is opposed to around a dozen birds (at last count) collected in
> Victoria, all in Autumn, Winter (? Spring). So without any evidence of there
> being any Summer records of Tas Boobooks, you would have to say they are much
> more likely to be migrants. They are just overlooked because of their
> similarity to mainland birds.
>
> As for whether the Tas bird is a full species, to me it's a matter of degree.
> I actually thought of this well before it was recently postulated & it is a
> bit odd that the bird is small compared to mainland birds, with some good
> plumage differences. I tend to think this bird is part of a relict boobook
> population, which is also true of NZ birds & perhaps the Red Boobook of NE
> Qld. Whether they (or the others) are different enough is a matter of
> conjecture. Be good if we had some Aussie taxonomists to decide these things,
> instead of people overseas. I think if you split this one, there are a bunch
> of other candidates waiting to be looked at from Tas, like the small Tas
> Magpie, the long shrike-like billed Tas Grey Shrike-thrush (bills are
> supposed to be smaller proportionally in higher latitudes, this has a bill at
> least 33% larger with no overlap; additionally has a distinct white throat);
> & wait there are more......
>
> As for the Pink Robin, the Tas bird sounds like a very weak subspecies
> anyway, so the only way to decide this one is to band some Tas birds & see if
> they turn up on the mainland.
>
> Kevin Bartram
>
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