that's right Philip, I wouldn't either...
the markedly slower flight & deeper wing-beats of Yellow-taileds when compared
to Glossy, or even Red-taileds, is rather obvious when u see both species
fairly often, as Sandy has pointed out earlier.
it actually is a good field character for discerning Yellow-taileds from
Glossy, but the flight patterns of Red-taileds & Glossy would be too close to
call with any accuracy I would say...
I would assume that WA Carnaby's would be similar to Yellow-taileds given their
close relationship, but I've not seen Baudin's often enough myself, without
checking the books first.
as for Baudin's...I don't know...???
cheers
martin cachard,
cairns
> From:
> To:
> Date: Fri, 13 Jun 2014 13:37:44 +1000
> Subject: Re: [Birding-Aus] Black Cockatoos in flight
>
> Forshaw's Australian Parrots book describes Glossy Black Cockatoo as:
> extremely buoyant flight with having slow, shallow wing beats, which differ
> markedly from the full flapping wing beats of the ..... YTBC............ So
> a different suggestion.
>
> Neither does directly mean that speed of flight is different. If it does it
> would not suggest that Glossy Black Cockatoo is the slower one, which was
> the question posed by Mark. I wouldn't use slow flight as a feature to
> identify a Glossy Black Cockatoo cf YTBC.
>
> Philip
>
> -----Original Message-----
> From: Birding-Aus On Behalf Of
> Sandy Gilmore
> Sent: Friday, 13 June 2014 10:03 AM
> To:
> Subject: Re: [Birding-Aus] Black Cockatoos in flight
>
>
> Hi everone,
>
> A very timely question since I frequently get Yellow-tailed Black Cockatoos
> flying over and infrequently get Glossy Cockatoos flying over.
>
> While enjoying the sunset a few days back I had both species fly over a few
> minutes apart and it was abundantly obvious that Glossy Cockatoos flap their
> wings at twice or more the rate of Yellow-tailed Black Cockatoos.
>
> This is in the situation where I presume both were returning to their night
> time roosts and were flying high over a mixture of forest and cleared
> paddocks.
>
> Aerodynamics experts would be able to explain this inter-specific difference
> based substantially on their relative body weights, and wing areas and wing
> spans.
>
> See http://jeb.biologists.org/content/150/1/171.full.pdf
>
> On another matter I have increased my White-throated Needletail sightings
> over summer by an order of magnitude, plus observing other interesting
> birds, by taking time to observe the sunset as often as possible.
>
> Cheers,
>
> Sandy
>
>
>
> Sandy Gilmore
> Arid Zone Ecologist
>
> Bush Heritage Australia
> "Morinda" 240 Mafeking Road, Goonengerry NSW 2482.
>
> Conservation Support Centre
> Level 5, 395 Collins Street, Melbourne Vic 3000
> www.bushheritage.org.au<http://www.bushheritage.org.au/>
>
> T: +61(0)2 6684 9178
> M: +61(0)427 686 985
>
> [Description: Description: Description: N:\Signatures\2012 General
> Image.JPG]<http://www.bushheritage.org.au/>
>
>
>
>
>
>
>
>
> [http://www.bushheritage.org.au/images/email/email-footer.jpg]
> <http://www.bushheritage.org.au/bha-email-footer-link>
>
> footer-img
>
> [PwC Transparency awards - Top 10 Finalist 2013. $5m to $30m category]
>
> Bush Heritage Australia was pleased to be recognised as one of the 10
> finalists in the revenue $5m to $30m category in the 2013 PwC Transparency
> Awards for the quality and transparency of our reporting.
> _______________________________________________
> Birding-Aus mailing list
>
> To change settings or unsubscribe visit:
> http://birding-aus.org/mailman/listinfo/birding-aus_birding-aus.org
>
>
> _______________________________________________
> Birding-Aus mailing list
>
> To change settings or unsubscribe visit:
> http://birding-aus.org/mailman/listinfo/birding-aus_birding-aus.org
_______________________________________________
Birding-Aus mailing list
To change settings or unsubscribe visit:
http://birding-aus.org/mailman/listinfo/birding-aus_birding-aus.org
|