At 18:00 on 7 January
1986 while watching a party of c.30 Red-rumped Swallows Hirundo daurica feeding over the eucalypt savanna on the eastern
slopes of Paga Hill in port Moresby, RKH noticed a bird fly across an open
space and perch on a building under construction below use. He thought it might
be a Blue Rock Thrush Monticola
solitarius and pointed it out to BWF who confirmed the identification.
The bird was observed
without binoculars for about five minutes in fading light and the following
notes were made. It was considerably larger than a Pied Chat Saxicola
caprata available for direct comparison and held itself in a typical thrush-like
stance. Upon landing it flicked its tail slowly downwards, a movement often
repeated while perched. Plumage details were difficult to determine in the
fading light, but it was thought to be uniform blue-grey with darker primaries,
a dark bill na dark legs. It eventually flew into the half completed building
and was lost from sight.
We returned to the area
at 06:00 the following morning, armed with binoculars. BWF spotted the bird
almost immediately and we watched it for nearly an hour in good light. The dull
image of the previous evening had changed overnight into a resplendent adult
male of the chestnut bellied race M.s.philippensis.
It was seen daily up to 19 January 1986 and appeared to range widely, although
it was often found around the houses in the early morning and late afternoon.
It was subsequently seen by 13 other observers.
The following
description is taken from notes made at the time. The bird was shaped like a
thrush, with a moderately long tail, often held pointing downwards and flicked
agitatedly. Head to chest and entire upperparts were blue-grey, primaries and
central retrices were darker. The wing coverts had small dark centres and
whitish crescent shaped tips. The feathers across the back, bordering the wings
and across the upper breast similarly had whitish crescent shaped tips. The
underparts from chest to vent were a uniform, deep chestnut-orange, sharply
contrasting with the blue-grey of the chest. The feathering at the base of the
legs was blue. The bill was slender and quite long for a thrush and uniform
blackish. The legs were also uniformly dark. The iris was large, prominent and
dark.
There are ten species
of rock thrush Monticola, five of
which are confined to Africa (Howard & Moore 1984) and are not considered
further here. The remaining five species are distributed across Eurasia. One
reaches no further east than north India. Four species can be found in
south-east Asia (King et al 1984) and all are at least partially migratory. The
chestnut-bellied race of Blue Rock Thrush M.s.philippensis
winters further south and east than any other species, reaching the Philippines
and Indonesia. The Blue Rock Thrush is the only one of these four to have a
blue breast and, in non-breeding plumage, to have scaly markings across the
mantle and on the breast (King et al 1984, Viney & Phillips 1983). Both
these features were noted on the bird at Paga Hill. This is the first record of
this species in Papua New Guinea and in the Australia region (east of the
Moluccas).
Howard, R. & A.Moore.
1984. A complete checklist of the birds of the world. Papermac.
King, B., M.Woodcock,
E.C.Dickinson. 1984. A field guide to the
birds of south-east Asia. Collins.
Viney, C. &
K.Phillips. 1983. New Colour Guide to Hong Kong Birds. J.R.Lee.
First
published in Muruk 2(2): 64-65 co-authored with B.W.Finch
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