A bit more to add to the recent discussion about Wet Tropics/Cape York
subspecies and rarities.
I had John Young look at the boobook photo taken on Mt Lewis by Josh and
his mates and he was satisfied that it was lurida. Even though the
quality of the photo was not the best, jizz and markings were right for
lurida in his opinion. He also said there did not seem to be any
indication of ocellata in the plumage, despite the quality of the photo.
Further, he is confident it is a fairly young bird - even younger than I
would have said. He said that whitish under the throat indicates a young
bird and that they lose that after a while. The fact that the bird did
not move probably indicates a young bird as well for lurida is often
very skittish and can be very difficult to get sight of.
I also asked him about the probable difference in breeding seasons of
lurida and ocellata and he agreed with my experience. He has found a
number of nests of lurida over the years, all in November, and more of
ocellata which were in the early to mid dry season - up until about
August-September. This would mean that it could be difficult for
hybridisation to take place. His opinion is that when one form is
brooding eggs, the other would probably have large young on the wing or
vice versa and then be in a different stage of moult. Like myself, he
has never seen any indication of hybridisation in lurida and both of us
doubt that it takes place, or if it does, very rarely. If there was
hybridisation, we should be seeing in-between birds from time to time
but we aren't. All are fairly standard lurida. There seems to be some
small differences, probably between sexes, and we think possibly age
variation as well. Young birds differ slightly again. We suspect this
may be the reason people are seeing "hybrids". Young lurida are on the
wing right now (January-February).
One is a rainforest bird and subject to rainforest conditions while the
other is an open forest bird and subject to very different conditions,
more so here in the tropics. Seasons in the tropics (just two - the Wet
and the Dry) can be very harsh and distinct. Even the eggs of lurida are
quite noticeably different in size and texture from the other two races
of Boobook. If there is extensive hybridisation, we have yet to be
convinced. I have been recording sound in September-October just as the
breeding season commences when birds are quite vocal and all sighted
have been normal lurida. We have both spent more time in those forests
than most people, both by day and by night, myself on Mt Lewis and John
in the Wallaman area.
I did not ask him about race boobook which seems to replace ocellata in
the very southern part of the Wet Tropics but the chances must be that
it is similar to ocellata in its breeding in these tropical areas.
Another interesting bird from the tropics - Rogers Pipit (race rogersi
of Australian Pipit - Anthus australis) inhabits mostly the estuarine
and saline flood plains in a fairly narrow strip right across the
tropics from about Lakefiled NP on Cape York to NW WA. Simpson & Day
show its range well. It seems to be habitat specific and never seems to
occur away from that habitat. It is worth looking for it on Nifold Plain
in Lakefield NP or Marina Plains to the north-east on Cape York
Peninsula where it is fairly common. When you see it, you wonder what
you have got - heavily spot-breasted, long-legged, a different jizz from
australis (more upright) and noticeably darker plumage. The first time I
saw it, I thought I had a vagrant species from Asia or elsewhere. It
does look like a distinct species but it needs someone to do some work
on it in the future to arrive at the correct answer. The race closest
to it superficially is exiguus from the highlands of New Guinea
according to Schodde & Mason in their Directory.
I have never seen it south of Nifold but Tony Ashton photographed a bird
south-east of Ingham from similar habitat a short while back, which
appears identical to the birds from Nifold and Marina Plains. So there
could be an isolated population in the Ingham area. If so, it would be
an extension of known range. I included it in my Wet Tropics book mostly
to entice people to watch for it and to create some discussion. Where
one gets Zitting Cisticola on the short-grassed marine plains, I would
be looking for this Pipit. Their habitat preference is similar.
Another which needs to be looked at more closely is the Collared (now
Torresian ?) Kingfisher group (within Australia). Despite what genetics
might say, if the southern race colcloughi is not a different species
from northern sordidus I will give up birding! I haven't seen the recent
paper by Anderson and others but in the field colcloughi is so obviously
different from the tropical sordidus which inhabits the entire Wet
Tropics. When I was guiding 15 years and more ago, people who were
familiar with southern colchloughi were always amazed at the difference
when first seeing sordidus. They usually doubted that it was a Collared
Kingfisher. When I lived behind the Gold Coast in southern Queensland,
one would sometimes have to look at a bird about the mangroves several
times to decide whether it was a Sacred or a Collared. One doesn't have
to do that in North Queensland where they might come together - the
difference is very obvious.
Colcloughi is a much smaller and perhaps daintier (different jizz) bird
with a proportionate bill while sordidus is noticeable larger (contra
Bergman's rule), sturdier, almost lanky with a very obvious large,
disproportionate bill. Some males have an almost massive bill. I have
played sound of colcloughi in territories of sordidus without a
response. However, play sordidus sound within a sordidus territory and
the reaction is immediate. David Hollands has photographs of sordidus
(taken at Innisfail) in his book Kingfishers and Kookaburras. Compare
them with photos of birds taken in southern Queensland.
Our race of Bassian Thrush (cuneata) also needs attebtion - another
which defies Bergman's rule.
Lloyd Nielsen
Mt Molloy Nth Qld
www.birdingaustralia.com.au
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