Howdy,
The photograph of the stated Audubon's Shearwater
accessed via Tony Palliser's home page that I
referenced at
>
http://users.bigpond.net.au/palliser/barc/img109-1.html
is following some further research on my part almost
certainly not a Townsend's Shearwater. Enticott and
Tipling (1997) describe the undertail coverts on these
birds as "variable, generally all dark with variable
small area of white at the base, usually evenly and
squarely demarcated (appear all dark at sea, unlike
Newell's or Manx Shearwater)."
This quite clearly does not fit the description of the
bird in question and at any rate Townsend's Shearwater
breeds off the west coast of Mexico and its occurrence
in eastern Australian waters must be extremely
improbable.
The undertail of Newell's Shearwater is described by E
& T as "between all dark of Townsend's and all white
of Manx, never all white (generally, inner coverts
whitish, extending and tapering to a 'v' shape or
point about halfway to undertail tip, and outer
coverts dark). This description seems to me to fit
Mike's photographed bird quite nicely and certainly
seems to contradict all accounts to hand of Audubon's
Shearwater.
The white extending on to the sides of the flanks (a
crucial feature of the bird Dion described) certainly
suggests Newell's Shearwater. As Mike Carter's 1984
bird is photographed from below it is hard to see this
feature. Looking between the trailing edge of the wing
and the tail at the top of the picture, some white is
apparent, but its extent is impossible to ascertain.
The other bird to eliminate is Manx Shearwater and to
my eyes at least this is perhaps more difficult.
Interestingly, this bird is not generally supposed to
show white extending up the sides of the rump but E &
T have a photograph of just such a bird (Fig. 4 p.
83).
I do not wish to directly contradict BARC's acceptance
of the photographed bird as an Audubon's Shearwater.
Am I missing something? How was this decision reached?
Cheers
AS
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