G'day Richard, Nikolas and Stephen.
I'm interested to know where everyone is getting their data from.
HANZAB shows that Tasmanian birds are bigger in all measurements so rather
than having proportionately longer wings they are just bigger all around, no
advantage in that for migration. Similarly there is not enough data in
HANZAB to compare average weights for the two ssp, but if the birds in Tas
are physically bigger in all measurements then they would have to be
heavier.
Cheers Jeff.
-----Original Message-----
From:
On Behalf Of Stephen
Ambrose
Sent: Thursday, 13 June 2013 11:13 AM
To: 'Birding Aus'
Subject: Pinks Robins (formerly "Possible Tasmanian
Morepork in Victoria")
Hi Nikolas,
Tassie Pink Robins are also slightly heavier than those found on the
mainland, in agreement with Bergmann's Rule (individuals in colder climates
have greater body masses than conspecifics in warmer climates). Heavier
birds have greater wing-loads, which may be alleviated somewhat by having
longer wings, which could explain why Tassie Pink Robins have slightly
longer wings.
Cheers,
Stephen
Stephen Ambrose
Ryde NSW
-----Original Message-----
From:
On Behalf Of Nikolas Haass
Sent: Wednesday, 12 June 2013 10:51 PM
To: Richard Loyn; 'Chris Corben';
Subject: Possible Tasmanian Morepork in Victoria
Hi Richard,
That's interesting. I am wondering why the Tassie Pink Robins are
longer-winged. This could indicate a longer migration/dispersion distance.
Just a thought.
Cheers,
Nikolas
----------------
Nikolas Haass
Brisbane, QLD
________________________________
From: Richard Loyn <>
To: 'Chris Corben' <>;
Sent: Wednesday, June 12, 2013 8:48 PM
Subject: Possible Tasmanian Morepork in Victoria
Hi Chris, I'm not convinced that Pink Robins make the crossing, in contrast
to Flame Robins. HANZAB says there is no evidence for such crossings, and
Tasmanian birds are subspecifically distinct (slightly longer-winged).
In Victoria (as you know) adult male Pink Robins mainly remain all year in
their breeding territories in cool temperate rainforest or wet mountain
forests with similar structure, along with some brown birds (perhaps mainly
adult females), although they tend to forage in more open situations
(including log landings). A few adult males and lots of brown birds move
into drier habitats for the winter, in foothill forests and in shady
multi-stemmed habitats such as coastal teatree thickets, also in
box-ironbark & regrowth river red gum, etc.
It's a similar story in Tasmania. Reporting rates go up in winter in both
states because birds are more widely dispersed and found in more accessible
places. There are records from Bass Strait islands (King & Flinders),
apparently referring to resident populations of the Tasmanian subspecies. I
don't know of any reports of falls of Pink Robins on Bass Strait islands or
the Victorian coast, whereas such events are quite often reported for Flame
Robins.
I hope this helps a bit. I wouldn't be surprised if occasional Pink Robins
crossed the strait but it seems there's no generally accepted evidence for
it and I suspect it's the exception not the rule. It may be worth checking
various reports of bird observations on small Bass Strait islands.
I look forward to hearing more about the boobooks and the Gould's wattled
bats.
Cheers, Richard.
Richard Loyn
Eco Insights
4 Roderick Close
Viewbank VIC 3084
ph: 03-9459 4268
mob: 0488-77 66 78
-----Original Message-----
From:
On Behalf Of Chris Corben
Sent: Wednesday, 12 June 2013 2:46 PM
To:
Subject: Possible Tasmanian Morepork in Victoria
Hi all
On a tangent, but Paul Brooks questioned that Pink Robins cross Bass
Straight, which made me realise I might have been mixing up stories between
Flame and Pink and various speculations based on the occurrence of Pinks in
silly places at times. Does anyone know? Does Pink Robin migrate across the
Straight?
Cheers, Chris.
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