The case for minimising the possibility of the Northern Pintail and Northern
Shoveler being escapes has already been eloquently argued by Rohan Clarke
and David Geering. Neither species has been kept in Australia and certainly
neither are established. So few foreign birds are established in Australia
that generally ruling out the risk of escapees is straightforward.
Both species are well known long distance migrants which have strayed not
only to Australia but also South America and Africa and the tropical
Pacific. Pratt (1987) records the status of both species. The Northern
Pintail is considered uncommon in Micronesia, common in Hawaii and
straggling to Line Islands, Tonga, Cook Islands, Society Islands etc.
Northern Shoveler common winter visitor in Hawaii, rare but regular in
Micronesia and vagrant to Tuamotu. North-eastern NSW-south east Qld is
probably the best location for receiving east Asian Pacific flyway vagrants.
eg American Golden Plover Byron Bay 1994, Black-backed Wagtail Fraser Island
1987, Blue Rock Thrush Noosa etc.
A pattern of breeding plumage male Northern Shovelers in winter/ spring is
emerging from Australian records. In both species eclipse molt is pretty
rapid and many long distance migrants including ducks end up out of plumage
sequence eg Short-billed Dowitcher at Price Saltfields. As a result they
also stand right out. That both birds looked so immaculate indicates they
may have recently completed the molt.
Australian Shelducks are recorded north to Brisbane Valley, Qld in drought
years so the Grafton record is not overly unusual. This spate of records is
more likely a result of more experienced observers giving Grafton and the
Clarence greater coverage. The Wollongong pelagic phenomena or for an
Arizonan example-the Patagonian Picnic Table phenomena. How often is one
rarity followed by another when every one starts searching and the Clarence
is good for waterfowl.
So conjecture that these birds are escaped seems like a tired argument to
me. On the opposite spectra recent records in NSW of Banded Honeyeater
(nomadic), Cotton Pygmy-goose (previous NSW breeding resident), Metallic
Starling ( migratory and also recorded in NSW in 1889) Great Bowerbird,
Yellow-bellied Sunbird may always carry a cloud of escapee provenance. None
of these species is well established in captivity in NSWand the majority
unheard of. To me it often seems everyone is very quick to say it is an
escapee with no evidence. Birds with wings will use them and often end well
out of range. As for feathers they have to be replaced as photoperiod and
nutrition dictates. How many genuine rarities are being dismissed as escapes
in a country where avicultural collections are licenced and well documented.
Dion
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