Mike, Chris,
I'm at the beginning of the learning curve at this, and am earnestly trying
to get my head around the progression of moult in Little Terns (LITE), so as
to be able to separate them in the field. It is devilishly hard, but I'm a
stayer. I have the disadvantage of not having handled them in the field.
To add my two bob's worth:
There is a specimen in breeding plumage in the Qld museum which is
completely without the dark tip on the beak. I thought initially that it may
have been misidentified, but on closer examination I could see that it was
indeed a Little and not a Fairy. I am fairly certain it was collected in
Moreton Bay. Most of the terns in the museum were collected in the storm
season, as I think I recall this one was (ie between Jan and April).
On 14.2.02 we saw a multi-flagged LITE in breeding plumage with no black tip
on the yellow beak. I recently learned that multi-flagging does not
necessarily indicate Aussie breeders, as all LITE were multi-flagged until
1998 when they stopped multi-flagging the birds considered likely to belong
to the northern population. (Those birds now have an orange flag - if Vic
banded- and a metal band.)
Does anyone know whether the Vic Museum has a decent range of LITE skins? Or
even any idea of how many? I would like to have a look at them if the
collection is good. There are about 35 in the Qld museum, but with most of
them cyclone collections (in breeding plumage), there is a lack of
representation for the months leading up to Xmas.
In Caloundra, SEQld, I have a lot of LITE currently without the dark carpal
bar. I had hoped that the absence of a carpal bar could be used for a short
time as an indicator of population origin, but now I'm not so sure. I have a
feeling I have seen birds going into breeding plumage without a carpal bar,
but I am relying on memory, and can't locate the notes to find the date.
For instance, I have received an opinion that the carpal bar is only absent
when the bird is coming out of breeding plumage, but if that is the case,
then I must have a lot of the Aussie breeders on the Caloundra sandbanks at
the moment, and I think that unlikely. Does anyone have an opinion on this?
Cheers
Jill
--
Jill Dening
Sunshine Coast, Qld
26º 51' 152º 56'
Ph (07) 5494 0994
> From: "Mike Carter" <>
> Date: Fri, 1 Mar 2002 21:25:19 +1100
> To: "Chris Corben" <>
> Cc: "BIRDING-AUS" <>
> Subject: Re: [BIRDING-AUS] Ballina Little Terns
>
> Chris Corben asked;
>
>> If Little Terns can have pale bill
>> tips and paler dorsal surfaces than most, then that won't help distinction
>> from Fairy Terns. Could I be seeing hybrids? My inclination is to think
> not,
>> because the birds with pale bill tips or pale backs looked otherwise like
>> typical Littles. I think it's more likely that at least some Littles
>> progress from dark tipped yellow bills through a stage where the black tip
>> is lost while the rest of the bill is largely yellow, then darken up all
>> over. Furthermore, I think it's quite likely that the paler upperparts
> could
>> be a result of fading. It's interesting that the juvenal showed paler
>> upperparts also. Any comments?
>
> Many Little Terns which breed in Victoria have only a microscopic amount
> of black on the bill tip even in full breeding plumage and some appear to
> have none. See e.g. ABW 17:(7) 346-348. So they don't have any black to
> lose. There were several examples in the Tern colony at Marlo in January
> (about 200 least terns of which c. 12 were Fairies) where variation in
> amount of black on the lores added to ID problems. There may have been some
> hybrids there too. I photographed one. I noted there again, that the Little
> Tern nests were very spread out, many metres apart, whereas the Fairies were
> in a discrete, compact colony. Best ID characters are still those we learnt
> in the 60's. Fairies are bigger, bulkier, shorter legged (especially tibia),
> heavier billed, and have less black in primaries. Typically, they're paler,
> less grey above, but even when together, in some, the distinction can be
> slight. Is it our older, less discriminating eyes, or has there been some
> gene flow?
>
> Mike Carter
> 30 Canadian Bay Road
> Mt Eliza Vic 3930
> 03 9787 7136
>
>
>
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