I have just got back from a couple of days of birding in Little Desert NP in SW
Victoria. It was my first visit to the area and was more an exploratory trip
targeting a couple of subspecies I hadn't seen previously. The birding was
excellent, with lots of birds in and around the National Park.
One of the target subspecies was the race hedleyi of the Slender-billed
Thornbill. The only other encounter with this species was just south of
Carnarvon in WA, so the ID was pretty easy. This time there is a the
complication of the presence of Buff-rumped Thornbills, which I was confident I
would be able to separate in the field. Now I am back home and have looked at
HANZAB and Ward & Paton (2004)
http://www.publish.csiro.au/?act=view_file&file_id=MU02048.pdf and having
listened to the CD of BOCA calls I am not so certain. Below are details of
sightings of various "pale-rumped" Thornbills and I would be interested in
people's comments on the likely ID.
The first two sightings were on the Salt Lake Track, a site recommended by
Frank Pierce. Both were in areas dominated by Banksia/Casuarina heath, with
scattered Eucalypts (Stringybarks?) which going by the epicormic growth had
been burnt in the previous 12 to 24 months (maybe the fires of late 2007?).
Some of the Broombush/Casuarina mallee around the trig had been burnt even more
recently (though may have been hazard reductions or wildfire - I am unsure)
with lots of earthworks around the perimeter of the fires.
The first group was approximately 8 birds that were feeding on the ground and
also regularly flying up into burnt branches approximately 500 metres south of
where you enter the low heath proper. They were difficult to get close to,
particularly keeping the between myself and the sun (and hence offering poor
views). They definitely had pale rumps, pale eyes and what I could see buffish
flanks - I could not get a good enough view of the scalloping on the forehead.
The call seemed close enough to Buff-rumped Thornbill, but not exactly the same
as the cal I was familiar with and definitely not a thin "tsip, tsip, tsip"
which was the field guide description.
A second group was detected was encountered further along (I susspect within 1
to 1.5km north of the Salt Lake) in an area near where some small salt lakes
(probably normally hidden when unburnt) occur on either side of the track.
These behaved and called the same as the previous group (though numbers were
probably greater - around 12). I assumed that this group like the previous were
Buff-rumped Thornbills.
The only other birds in this habitat were Hooded Robins (a pair in the
vicinity/associating with each group of Thornbills), Australian Pipit and
Variegated Fairy-wrens.
A single bird was encountered in the only patch of heath along the Nhill-Harrow
road that doesn't look like it had been burnt in the previous five years (about
23km south of Nhill). This is a narrow (50m) strip between two tracks which has
farmland to the north. A single bird was heard and seen briefly as it flew into
a Banksia (about 1m high and 1.5 in diameter) only about a metre from the
track. The call was very different - a harsh trill. Pishing got no response,
and walked around the shrub and the bird didn't flush. Eventually I walked to
the shrub and the bird flushed about 5 metres before disppearing into the base
of the shrub, calling the same way. This happened a few times with the bird not
flushing until I virtually touched the banksia it was in and the flying between
about 3 and 10 metres before returning to original bush. Each time it flew to
the base of the shrub and disappeared into the middle - on one occassion I
could see movement but no shape. It returned to the original shrub, where I
then left it. Flight views only were obtained, with the rump pale, and the
black band on the tail being considerably more obvious than on Buff-rumpeds I
had seen in the past. I assumed that this bird, despite poor views, was a
Slender-billed Thornbill.
My original plan was to stay at Karte CP (north of Pinaroo) as I had been told
that Slender-billeds could be seen here. On the way, stopped at Pertendi Hut in
Ngarkat CP and at the start of the Border track, came across another group of
Thornbills associating with Inland Thornbills in the canopy of a Eucalypt in
amongst more Banksia heath. This group was smaller, but due to habits was once
again assumed to be Buff-rumped Thornbills. Incidentally didn't end up staying
at Karte, but did the walk (only seeing Inland Thornbills) and the habitat
looks very different to other sites I visited.
I think I made three mistakes on this trip:
Assuming that, like most mallee specialists, the species would prefer long
unburnt habitat. However this does not appear to be the case. Because of this I
almost instantly assumed the birds at Salt Lake Track were Buff-rumped and I
also didn't look in what would be suitable habitat along the Nhill-Harrow road
as I thought this had been burnt too recently.
Not listening to the BOCA CD before I went away. Reading the field guide I had
assumed the calls would be distinctive and very different to Buff-rumped, which
on returning home I would say is not the case.
Not observing the crucial ID features (particularly scalloping) though I would
say I based my initial ID with the first two assumptions above (straight away
thought Buff-rumped and so didn't check the right features).
I would be interested on any comments on these observations (particularly
Buff-rumped Thornbills in Ngarkat) and one thing is certain will return to
Little Desert next time (with the family) hopefully better informed to make the
correct identification. Will also return in spring when hopefully all birds are
calling even more and can use call as a better ID feature.
Cheers,
Peter
_________________________________________________________________
Looking to change your car this year? Find car news, reviews and more
http://a.ninemsn.com.au/b.aspx?URL=http%3A%2F%2Fsecure%2Dau%2Eimrworldwide%2Ecom%2Fcgi%2Dbin%2Fa%2Fci%5F450304%2Fet%5F2%2Fcg%5F801459%2Fpi%5F1004813%2Fai%5F859641&_t=762955845&_r=tig_OCT07&_m=EXT==============================www.birding-aus.org
birding-aus.blogspot.com
To unsubscribe from this mailing list,
send the message:
unsubscribe
(in the body of the message, with no Subject line)
to:
=============================
|
