Yes, as with the YFHEs there is a big altitudinal element with the Duskies
and a question is whether those seen in the cooler months are stayers or
from elsewhere. As Philip points out in his note, the Duskies build to an
apparent ('garden') peak in April (nothing unusual in the current reports)
and are generally absent in June/July. I agree that encouraging reports of
a possible 'last sighting' - say beginning in June - would be useful. It
can be predicted that most 'first reports' will be in August, but in either
case you won't know whether they're local breeders or transiting birds.
-----Original Message-----
From: Julian Robinson
Sent: Monday, 20 April 2009 1:49 PM
To: Geoffrey Dabb;
Subject: DW-s Migration Narrabundah
Yes I feel a bit bad after reporting those numbers of Diamond
Firetails on two separate days at two adjacent locations in
CallumBrae. Since that day I've never seen one of the buggers there,
it was definitely an erroneous impression! So yes, are they just
nomadic, or also migratory?
About Duskies - and with apologies to those who disagree with this
hotly debated possibility - I think that the single best way of
leading towards a quick initial understanding of what goes on with
them at the Canberra end is for people to post about all the DWSs
they see on this chatline for one season; say another 6 or 7
months. Then if/when they disappear it can be determined
retrospectively by looking for the last post for the season. Or
some reasonable conclusions might be drawn about numbers and even
spatial distribution of those that hang around as well as those that move
out.
Personally I wouldn't mind if 150 messages appeared on this topic, it
would all be interesting in the end and add a lot to our current
formal databases. And these posts can easily be ignored or deleted
by scanning the headings. I honestly don't know why people have
problems with this, unless they are receiving all their chatline
posts unsorted and into their inbox, which would be very irritating
but is easily fixed.
Of the other two possibilities, relying on filed surveys will never
work in practice because most people don't put in records for
everything they see. As has been discussed before, it's not a
successful way of determining last sightings of a season. And
arranging to send all DWS sightings for the next 8 months to one
nominated member will not work as well, simply because most people
will forget about it. It's the visibility and positive reinforcement
of the chatline that makes it ideal for this purpose (chatting about
DSWs and getting consistent reports).
Other than establishing such a mini-reporting-project here on the
chatline, I can't think of any other way of capturing so much useful
info on this kind of topic.
Julian
At 10:40 AM 20/04/2009, Geoffrey Dabb wrote:
>The wanderings of the possibly migratory Diamond Firetail (not to mention
>the DWS) are one of those things we must get to the bottom of one day, if
>ever we can get all the accumulated local data.
>
>-----Original Message-----
>From: Jack and Andrea Holland
>Sent: Sunday, 19 April 2009 9:27 PM
>To: ; Julian Robinson
>Subject: Re: [canberrabirds] DW-s Migration Narrabundah
>
>Julian, interestingly the dusky woodswallow and welcome swallow also have
>been associating in my local patch this month, after being absent from here
>since before Xmas. I can't recall these two species consorting previously.
>
>Again they don't seem to be in any hurry to leave, with 5 and 15
>respectively late today almost in the same spot as they were on Monday
>morning. Also in the active MFF were 9 female/immature flame robins, the
>biggest group I've seen here for several seasons, and an altitudinal rather
>a spring/summer migrant. Also noticeable in this month's MFFs have been
>diamond firetails (up to 25 seen together) and yellow-rumped thornbills,
>both non-migrants.
>
>I've really been enjoying all the chat line postings of the continued
>presence of the dusky woodswallow in such good numbers of a species thought
>to be declining. However, I don't expect them to be leaving quite yet, as
>they one of the last migrants to leave, often staying round until about the
>second week of May, and with some over wintering. At least in my patch I
>see my highest numbers of welcome swallows during the winter, often near
>water.
>
>Jack Holland
>
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