It was Del Richards and I who made the original Pacific Swallow
submission to BARC. Several short-tailed swallows which differed from
the local Welcome Swallows were netted along with Welcome at the local
rubbish dump at Newell Beach, north of Mossman, N Qld.
BARCs decision (which was made more than two years after the submission
was lodged) was that the birds were/ /"female Welcome Swallows". We have
never accepted that several good reasons. Our submission included 12
photographs covering a bird in the hand along with an adult Welcome
which made a great comparison, and photographs of both species together
on power lines. David Stewart obtained sound of the Pacifics at the time
and produced sonagrams which gave a /very /different pattern from the
call of Welcome (which apparently does not vary to any extent throughout
its range).
Since those days we have learned much more about these swallows and
agree they can be difficult to separate in the field. However, when one
sees them sitting side by side with Welcome, there are some subtle
differences, apart from the very obvious tail length/shape. The only
problem is that one has to separate them from immature Welcomes which
often also have short tails.
We believe the basic, most important character to separation of the two
species (mostly in the hand) is colour of the base of the mantle
feathers. (This can also be seen at times (and is obvious) in perched
birds when wind is blowing and the mantle feathers are lifted). Base
colour of mantle feathers is very extensively white in Pacific but
extensively grey in Welcomes at all stages (though varying with age but
still overall grey). Our birds which had extensive white bases to the
mantle feathers corresponded exactly in that aspect with a specimen of
Pacific (/H. tahitica frontalis/) we obtained on loan from the PNG
Museum before we completed the submission.
When BARC could not agree after a lengthy period, the submission was
sent to Dr Richard Schodde at CSIRO, Canberra for expert opinion. This
important feature (colour of base of mantle feathers) was apparently
treated lightly by both BARC and Schodde. We believe that both BARC and
Schodde erred in not placing more emphasis on base colour of the mantle
feathers and not following it through. However, other characters, mainly
dealing with tail shape and structure were used to make the final
determination that they were Welcome Swallows. It appeared that the main
thrust was to compare them directly with the race /frontalis/. Because
of a slightly different tail structure with distinct markings, we
considered the birds to be most likely an undescribed race. Later,
Schodde & Mason (in The Directory of Australian Birds - Passerines)
described a new race of Pacific (/albescens/), apparently splitting it
from the widespread /frontalis /and naming the northern Torres Strait
Islands (Saibai, Boigu and Duaun islands) as the core "Australian"
range. These were described from specimens much farther to the east in
PNG, one from Brown River (Port Moresby area) and another from Amazon
Bay even farther to the east. In describing this race, the white base to
the mantle feathers was given prominence. However, none of us who have
visited those Torres Strait islands can find swallows there - I have
been to Saibai and Boigu a number of times and have yet to record a swallow.
Since the BARC decision, I have been examining swallow specimens in
various museum collections around Australia as the opportunity arises
and have only two collections left to examine. Contrary to the statement
in BARC's final report that tail measurements and patterns "were within
the range of variation of female Welcome", all the evidence to date
strongly supports our opinion but almost nothing supports the BARC
decision. Indeed, I have seen nothing to date which is within the range
of variation of female Welcome Swallows. In fact nothing comes close to it!
In its final report, BARC after adopting the decision that they were
(immature) female Welcome Swallows, stated that/ / "It should be
stressed that not all questions about these Mossman birds have been
answered. One could rightly ask why have such short-tailed Welcome
Swallows not been reported by birdwatchers elsewhere in North-East
Queensland or Australia? Why is it that most people that visit these
birds have been impressed by the patterning of the undertail-coverts?
Does this vary with age? This case highlights the gaps in our knowledge
about age-related variation in tail-pattern and length of Welcome
Swallows, and the migrations of sub-adult birds".
Simply, all questions were "not answered" because they were not Welcome
Swallows! The base colour of the mantle feathers ruled Welcome out.
Our side of the story has never been told publicly but if anyone would
like to see a copy of an account, part of which was forwarded to the
Hanzab editors, in regard to Pacific Swallow in this area and relating
to our original submission, together with further current thoughts,
please email me and I will forward it (4 page Word Document). That too
is worth reading as a balance to the BARC report.
My recommendation to anyone visiting N Qld is to go and see these birds
- Newell Beach near Mossman is probably the best site. These swallows
occur on the NE Qld coast only within the same small area in which the
migratory Barn and Red-rumped Swallows occur. They do not occur far
south of Newell Beach e.g. Port Douglas or Cairns. We have no doubt that
sooner or later, Pacific Swallow will be on the Australian list.
Lloyd Nielsen
Mt Molloy
Nth Qld
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