Shorely you mean "Beware the Tides of March"
On 15/03/2011, at 3:55 PM, Chris Gregory wrote:
Yup - one of those days ....."Beware the Ides of March"
Cheers
Chris Gregory
On 15 March 2011 16:17, Carl Clifford <> wrote:
Sorry Jill, it's one of those days.
Carl
On 15/03/2011, at 4:11 PM, Jill Dening wrote:
I knew the answer was out there somewhere :-) Why didn't I ask you
before,
Carl? Cancel the geolocators!
Jill
Jill Dening
Sunshine Coast, Queensland, Australia
26° 51' 41"S 152° 56' 00"E
On 15/03/2011 1:32 PM, Carl Clifford wrote:
Jill,
Perhaps the best answer to where and when they go is that they
take Tern
about?
Cheers,
Carl Clifford, (diving for fox-hole)
On 15/03/2011, at 2:09 PM, Jill Dening wrote:
Carl,
You have asked a bigger question than you realise. In short, they
are
northern hemisphere breeders and they spend the austral summer in
the
southern hemisphere. Flying through the East Asian-Australasian
Flyway,
they arrive around November and most are gone by sometime in April.
The Sunshine Coast is a hotspot for migratory terns, but as you
can see
from the numbers supplied, they have a peak in late summer. We don't
know the answer to the question, "where do they spend the height
of the
Australian summer" because I have asked many times, and never
received a
satisfactory answer. If they do spend the summer in Australia,
there are
no reported concentrations, and the only possibility is that they
spread
out into very small, unnoticeable groups in southern Australia.
Or, it's
possible that they go to Pacific Islands (but where?). However, they
pass through the Sunshine Coast region on their way north in late
summer
early autumn in larger numbers than is the stable summer population.
Because there has been little banding of migratory terns (some
Commons
flagged orange in Victoria over the years, but no individual
marking) we
don't know exactly where our migratory terns breed. They breed in
places
like eastern China, Japan, the Philippines, and I think Mongolia.
However, I'd love to know exactly where they go. We need satellite
trackers and in certain cases, perhaps geolocators.
I think there are possibly numerous breeding locations and
timetables
for the East Asian subspecies of Common Tern (Sterna hirundo
longipennis). I have no proof, only questions and hints which lead
me to
think so.
Nor do we know where the Australian-breeding Little Terns (Sternula
albifrons sinensis) go during the austral winter. We know they don't
join the breeders in Japan, which breed during the northern
summer. We
know this because there has never been a record of an Australian
breeder
in Japan amongst their Little Terns. The northmost Australian
records of
this group are my own in Maroochydore, Sunshine Coast in early
autumn,
and a single record by Clive Minton of a bird seen on Swain Reefs
off
Qld (or was it the Cap Bunker?) in July, 2000. So we definitely need
geolocators for Australian-breeding Little Terns. I think
geolocators
would be suitable because they tend to return to the same breeding
sites.
I should explain for clarity. The subspecies of Little Tern which
breeds
in Australia during our summer is the same subspecies of Little Tern
which breeds in the northern hemisphere during the northern
summer. They
are different populations, and whilst the two populations mix here
in
Australia, their breeding habits are out of kilter with each other.
I haven't gone into it too far, but if anyone wants to ask more
questions, that's OK. It's rather complicated.
Cheers,
Jill
Jill Dening
Sunshine Coast, Queensland, Australia
26° 51' 41"S 152° 56' 00"E
On 15/03/2011 12:38 PM, Carl Weber wrote:
Hi,
Where have the terns migrated from and where are they going to?
Carl Weber
-----Original Message-----
From:
On Behalf Of Jill
Dening
Sent: Tuesday, 15 March 2011 8:59 AM
To: birding-aus
Subject: [Birding-Aus] Tern migration peak has passed on the
Sunshine
Coast,
Qld
Hi Everyone,
Last night we did a count of migratory terns arriving to roost in
Noosa,
Qld. The vast majority of these birds are Common Terns, but also
included are Little Terns and White-winged Black Terns. This
confirmed
that the migration peak has passed in our area. Unfortunately we
only
conduct one count each month, limiting our knowledge of the
actual peak,
but below are some figures going back to Nov, 05, with dates.
Note that
there was a gap in data collection between January and December
2007,
and that we missed a count in March, 2010.
Birds are normally counted on the wing in blocks of 10, so the
figures
are never exact. Occasionally at peak periods they are counted in
blocks
of 50s, or even 100s rarely.
Cheers,
Jill
Survey_Date Sum Of Number_Seen
28-Nov-05 2380
14-Jan-06 12560
08-Feb-06 38340
08-Mar-06 14910
12-Mar-06 6020
15-Dec-06 573
15-Jan-07 2050
19-Dec-07 2740
17-Jan-08 2930
21-Feb-08 6650
15-Mar-08 1900
22-Apr-08 765
15-Dec-08 60
12-Jan-09 15030
11-Feb-09 1280
05-Mar-09 7400
09-Apr-09 5150
23-Jul-09 6
21-Aug-09 1
10-Dec-09 1170
18-Jan-10 2454
16-Feb-10 6330
15-Apr-10 3379
20-May-10 369
15-Jun-10 264
12-Jul-10 268
13-Aug-10 385
23-Nov-10 7280
07-Dec-10 11000
27-Jan-11 12830
24-Feb-11 21110
16-Mar-11 7170
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