A key feature of Yellow Bittern Ixobrychus sinensis in adult and juvenile
plumages is the black primaries and secondaries. In adult females and in
juveniles of Little Bittern Ixobrychus minutus the primaries and secondaries
are pale grey-brown or at best dark grey-brown but never black. This shows well
in museum specimens (some of which have been incorrectly labelled in the past)
even if not in all field guides. A juvenile or female Ixobrychus with little or
no contrast between primaries/secondaries and the rest of the upperwing is most
likely a Little Bittern Ixobrychus minutus. Males of the two species are
readily separated on back colour.
Timing of observations of Little Bittern in north Queensland is of interest to
understanding the migration of this species. Recent records confirm that the
vast grass/reed wetlands of southern New Guinea may indeed be the main winter
haunt of Australian Little Bitterns. Observations in north Queensland in March
may be of birds passing through to New Guinea. However, resident populations
are known from elsewhere in tropical Australia, notably Lake Kununurra in WA. A
similar situation (resident and migrant populations in the tropics) applies to
Yellow Bittern north of the equator.
Roger Jaensch
Wetlands International - Oceania
Level 4, Administrative Building
King Edward Terrace, Parkes ACT 2600
GPO Box 787 Canberra ACT 2601
Australia
tel: +61-2-6274-2779
fax: +61-2-6274-2799 or -2735
email:
>>> <> 31/03/1999 8:03:19 am >>>
>Date: Mon, 29 Mar 1999 09:54:21 +1000
>To: birding-aus
>From:
>Subject: Little versus Yellow Bittern
>
>A week ago whilst a number of us went with Lloyd Nielsen in search of
Buff-breasted Button-Quail at Wondecla, I happened to enquire as to the
difference between Little and Yellow Bitterns. This was a result of a visit
to the Cairns Croc Farm the week before and I saw two birds fly up out of
the reeds that looked very pale and showed no dark markings on the wing at
all - I wondered then just what was the difference between the two species.
>On Saturday 27 March 7 of us including Lloyd went to the croc farm armed
with step ladders for a more elevated view over the reed beds and 5
different guides to try to see if we could confirm one way or the other if
the two species might possibly be there together.
>We stood for 3 hours and watched more than 12 single flights from one part
of the reeds to another - some were long flights and we had some clear
views of both male and female Littles - or so we thought.
>I saw one bird from the top of the steps I was on and it was sitting in
the reeds and did the typical Bittern pose of stretching its neck. I did
not see any dark feathering on the mid stripe down the chest and the other
stripes down the chest were very pale yellow-brown. The books seem to
indicate that both male and female Littles have dark feathers in this
central stripe and we felt that the birds might possible be immatures.
There are few descriptions of these in the various texts so we left still
unsure.
>We felt we saw 4 and possibly more birds over the three hours and it was
quite hot and sunny at the time so the birds are very active even in those
conditions.
>If anyone is planning a visit up North over Easter then give the central
reed bed a thorough going over as I'm sure you will see the birds with a
little patience.
>The people at reception can direct you to the right pen.
>Regards
>Max O'Sullivan
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