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Dr Phil Hansbro I Tel: (h) 01223 514441 or
Dept of Pathology I 01223 514434
Tennis Court Road I (w) 01223 333545
Cambridge University I Fax: 01223 333346
Cambridge CB2 1QP I
UK I Email:
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Sorry for the delay I have been really busy.
On Fri, 12 Sep 1997, Teet Sirotkin wrote;
> Wandering tattler is not a difficult bird to identify, especially if you
> got both species together. As you surely know, the calls are completely
> different and the are also structural differences, like longer wings
> (compared to tail tip) on the wandering tattler. Furthermore, the bird was
> easy to pick out immediately, being darker, with a darker bill, although
> proper identification called for closer scrutiny. We were lucky enough to
> observe the bird(s) at a distance of 15m with spotting scopes, so we could
> even se the longer nasal groove and the difference of the scales on the
> tarsi. The fact that the wandering tattler was foraging on the rocks, while
> the grey-tailed preferred the mud is of course not determining, but a good
> indication. I'm well aware of the fact that wandering tattler is not often
> recorded in N.Z., but I think it's annual (does anyone know the exact
> figures?) and probably largely overlooked.
I am sorry I am just jealous as I haven't seen Wandering Tattler in NZ.
Although I am not sure about the bill being darker and I have never been
convinced that I have seen the nasal groove of any tattler even at very
close range. Tattlers in general are not that common in NZ so I doubt that
Wandering would be overlooked - if you find a Tattler in NZ you must then
ID it. In Fiji and Polynesia the vast majority of Tattlers are Wandering
and most of them are on the beaches. Also one of the best ID features is
that in Wandering the supercilia meet across the forehead whereas in
Grey-tailed they do not.
> Talking about the seabirds though, I must admit my inexperience and lack of
> knowledge. The Pycrofts petrels were identified on the grounds of darker
> caps and especially the lack of white on the outer tail feathers. I'm aware
> of the fact that Cook's petrels have less white in the tail than many field
> guides denote (I even have a tail at home!), but after seeing 100+ of
> Cook's fairly well, we thought that at least two birds looked definitely
> different.
There has been much said about the identification of Pycroft's Petrel most
of which I have found to be inaccurate - they are one of, if not the, most
difficult to identify seabirds in the world. They do not look
significantly different in terms of plumage or jizz in the field and it is
only by close scrutiny of very subtle features that they can be
identified.
They are often spoken of as having darker caps - this point is not true
and is misleading. When in the hand the visible texture of the dark upper
contour feathers, especially on the head, is similar to velvet and changes
colour and darkness depending on the angle of the feathers. This is not a
good feature.
I am also unconvinced that there are significant differences in the amount
of white in the outer-tail between they look very similar to my eyes. This
*rumour* may have propagated by the photograph in Harrison's photographic
guide it is not a good photo. Also one or both of the Cook's shown are
probably Masatierra and one of the Stejneger's Petrel photos is probably
Cook's so it is a bit of a mess really.
It is also likely Pycroft's Petrels are relatively faithful
to the oceanic seas adjacent to their breeding islands and are less likely
to stray to the relatively crowded seas around Cook's Petrel breeding
Islands such as Little Barrier.
So how do you identify them?? Well the only consistent features that I
have found are that the dark tips to the central forehead feathers extend
to the base of the bill in Pycroft's but not Cook's. Also the carpal bar
on the underwing of Pycroft's is slightly thicker and more extensive than
Cook's. It is also possible to identify these birds depending on the state
of the upperwings as they differ in having differing moult stages at
different times of year as Pycroft's breed later than Cook's.
There is no substitute for going to the breeding islands and examining
these birds in the hand.
> The Westland black petrels were essentially identified on the fact that it
> was more likely to encounter Westland blacks this close to Punakaiki. The
> Blacks should be on their breeding grounds in the Hauraki Gulf during this
> time. (Terrible way of identifing birds, I know!) I must admit I can't be
> sure of the id on this one.
>
Last winter we had several prolonged (several hours) views on several
several different dates in different months of Westland Black Petrel off
the New South Wales coast in Australia from Sydney and Wollongong.
Westland blacks were previously very rare with 1 or may be 2 accepted
records one of which was a beachwashed specimen. Black Petrels are much
commoner being recorded almost annually usually in November. Photos of
some of these individuals are shown on Tony Palliser's web page
We became quite accomplished at identifying them and these are our notes;
Westland Black has a slightly more barrel-chested appearance but did
appear much smaller than we imagined one would. We estimated the size to
be ~20% longer in the wing than Solander's. The wings were held in a bowed
fashion which may have contributed to the apparent small size. However,
size is subjective and more emphasis should be placed on bill
shape/structure/pattern. There is less difference in size between these
species than the vaiation within them.
The bill of Westland is distinctly long and pointed and does not show a
large bulging unguis to the same degree as Black or White-chinned although
the unguis is still big and the maxilliary unguis is very long and hooked
at the tip providing a strange drooping appearance to the tip. The long
hooked tip extended a long way through an imaginary line drawn along the
lower edge of the ramicorn. The Mandibular unguis is square in Westland as
opposed to rectangular in Black and White-chinned which makes the bill
hook look even more obvious in Westland.
In general the bill of Westland is "cone-shaped" as a result of a deeper
base and a long latericorn which has straight edges. There is an overall
impression that the bill tapers dorsally and the culminicorn and ramicorn
seem to converge an impression enhanced by the unguis being wholly black.
There is a more gradual slope from the culminicorn to the crest of the
unguis in Westland.
In Black the upper edge of the latericorn is concave and shorter giving
and almost upturned appearance of the latericorn. In Black the combined
effects of; the nostrils being widely separated from the very bulbous
maxilliary unguis, a concave upper edge to the latericorn with convergence
of the culminicorn and ramicorn, the lack of a distinct hook and a
relatively short, deep bill produce a short-thick-billed appearance with
is ~rectangular.
The extent of black on the bill is greater in Westland. The distal1/3rd of
the nostrils, the whole culminicorn, whole maxilliary and mandibular
unguis being black. Also the cuting edge has more black in a coneshape
with concave edges, resulting in a kind of trumpet shape, as it runs from
the unguis towards the bill base.
The colour of the bill also differs between the 2. The latericorn and and
teh ramicorn of Westland are yellowish with a green tinge whereas in Black
they are horn coloured. In Westland the nostrils are a contrasting
horn/white colour whereas in Black there is no contrast.
I can't remember off hand what they are but a lot of the Procellaria
Petrel photos in Harrison's photographic guide are incorrectly identified
or not good enough for conclusive identification.
I haven't read this through so appologies for any mistakes.
Cheers
Phil.
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