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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