Are Dusky Woodswallows migrants

[martin butterfield <>]

Geoffrey

Thank you for the kind words.  I have included a link to the archived version of your message as a comment to my original blog entry.

I note your comment about Dusky Woodswallows being woodland, rather than garden birds.  Out here in darkest Carwoola the places that I usually see them are perched on phone lines, or shrubs along fence lines, overlooking paddocks with hosses.  The way they hawk from these perches makes me think they are feeding on the insects stirred up by the horses (or those attracted by equine by-.products).  I could, but won't, pursue a simile about Cattle Egrets!

When the birds deign to enter my GBS site they ae generally well up in the sky, certainly over tree-top height.

Martin

On Fri, Apr 24, 2009 at 11:00 AM, Geoffrey Dabb <> wrote:

Great work, Martin.  I hope others will follow that link.

 

I shall not imitate the cracked record and repeat my position on the use of ‘migrant’.   However I revoice my protest against the use of the suggested opposite, ‘stayer’, for a bird seen in Canberra in Winter that for all anyone knows might have been in Tasmania the week before.

 

The summer/winter maps in the BA 98/02 atlas are worth a look:

 

 

The winter map shows some records for Canberra, the most pronounced movement being north from Tasmania and the area (se NSW, e Gippsland) to the south of Canberra.  This I think lends support to the view that many birds seen in Canberra in the ‘moving’ months (April being typical) are passing through.  Note that the species does not in general favour coastal areas.

 

On the value of the Garden BS data, non-Canberrans might need to be told that these 3ha sites are not limited to gardens but in some cases take in parts of woodland reserves.   I would not regard the DWS as a ‘garden bird’ and I would not expect it below tree-top height unless the site included some woodland-type habitat.

 

However, a characteristic of this species is that it is quite frequently observed flying in numbers at extreme heights.  At that height, they can turn up anywhere, but an observer who does not constantly scan the skies for such flocks is likely to miss quite a few of them.  Your reference to numbers in Curtin makes me think that the eagle-eyed Richard Allen is bringing to account over-flyers that he, but perhaps not the average bird-bath-watcher, has been able to pick up.  Even under the (I think now abandoned) protocol that non-site-using overflyers were not to be recorded does not rule out high flocks because it is almost impossible to say that they are not feeding on high-flying insects.

 

From: martin butterfield [
Sent: Thursday, 23 April 2009 5:43 PM
To: COG List

Subject: [canberrabirds] Are Dusky Woodswallows migrants

 

Following the recent discussion on this topic I have ferretted in the GBS database to see whether value can be added to the debate.  As the result:

• is too long for Gang-gang;
• but doesn't cover all the bases that need a lid for CBN; and
• some folk may not like an attachment

 I have put the outcome at http://franmart.blogspot.com/2009/04/are-dusky-woodswallows-migrants.html.

Martin