A while ago, a leg-flagged wader was reported on this list along with a
request for information about them. Somewhat belatedly, I thought I would
respond with a summary of the wader leg-flagging program in Australia and
elsewhere in the East Asian ? Australasian flyway.
WHAT IS A LEG-FLAG?
A leg-flag is a sort of modified plastic colour-band. It differs from
normal colour bands in that a rectangular tab projects from it. Although
small, this tab makes a leg-flag on a wader much more conspicuous than a
colour-band. Most leg-flagged waders have a leg-flag on the right tibia, and
a metal band on the right tarsus (above and below the ?knee? respectively).
There are also a few waders with the leg-flag on the tarsus rather than the
tibia (this was the practice used when leg-flagging was piloted, and is
still standard practice for Sanderlings and Turnstones).
WHO PUTS LEG-FLAGS ON WADERS?
Several teams of wader banders in Australia and (presently) one in Asia
routinely place a leg-flag on each wader that they band. Different colours
are used in different localities:
1. Orange leg-flags (a rather dark shade of orange, sometimes mistaken in
the field for red). Flagging occurs on the Victorian coast, mainly in Port
Phillip Bay, Westernport Bay and Corner Inlet; a few birds (especially
Sanderlings and Turnstones) are flagged in the extreme south-east of South
Australia. (Victorian Wader Study Group)
2. Bright yellow leg-flags are placed on birds caught in North-west
Australia, at Roebuck Bay, Eighty Mile Beach and Port Hedland. (Australasian
Wader Studies Group)
3. Green leg-flags are placed on birds caught in South-east Queensland.
(Queensland Wader Study Group)
4. White leg-flags are placed on waders caught in New Zealand. (New Zealand
Wader Study Group)
5. Blue leg-flags are placed on birds banded in Japan. (Bird Migration
Research Centre)
WHY DO THEY DO THIS?
The idea is to unravel the movements of waders in the East
Asian-Australasian Flyway, with the ultimate aim of identifying the breeding
and non-breeding areas of every population of waders, and the migration
routes between them. It is an interesting field of research in itself, but
the main motive behind it is conservation: an essential first step in
protecting and managing the migratory staging areas of waders is to find out
where they are.
Until the early 1990s, most direct information on wader movements came from
banding studies in which numbered metal bands were used. Leg-flags were
piloted in Victoria in 1990 and quickly caught on because they are so easy
to see in the field: unlike band recoveries, which are nearly always made by
banding groups or Asian hunters, leg-flag sightings can be made by any
birdwatcher. The reporting rates for orange (Victorian) leg-flags are much
higher than they are for band recoveries: 17 times higher for overseas
sightings and 39 times higher for sightings within Australia. The
combination of leg-flagging, banding and counts is rapidly improving our
knowledge of movements of waders between Australia and their breeding
grounds. Their migration strategies are proving to be quite beautifully
intricate and diverse: the fine details differ between all species, there
are different routes for different populations of the same species,
different routes for different age categories, different choices of staging
area depending upon weather conditions and so on.
WHAT SHOULD YOU DO IF YOU SEE A LEG-FLAGGED WADER?
Tell some-one who cares. Sightings of leg-flagged waders outside their
banding areas (which were listed above) are genuinely helpful and well worth
reporting. Place and date and colour of leg-flag are the key things to
report, but other details such as age of the leg-flagged bird, % of breeding
plumage, and the number of unflagged birds accompanying it would be welcome
too. It is also worth checking leg-flagged birds carefully for other bands:
various projects are planned in which an additional colour band is placed on
one of the tarsi. If such a bird is encountered, it is important to note the
relative positions of leg-flag, colour-band and metal band.
Leg-flag sightings can be sent to the Australian Bird and Bat Banding
Scheme, GPO Box 8, Canberra, ACT 2601 (Email:
Alternatively, they can be sent directly to the data curators of the banding
teams:
Clive Minton (VWSG, AWSG):
Peter Driscoll (QWSG):
Adrian Riegen (NZWSG): 231 Forest Hill Road, Waiatarua, Auckland 8, New Zealand.
Kiyo Ozaki (Japanese Bird Migration Research Centre):
A final note: leg-flags are easy to see in the field - but they are easier
to see if you are looking for them. Searching for leg-flagged waders can
actually add to the fun of wader-watching (if such a thing is possible).
This is clearly known to the wader-watchers of Hong Kong, who made more than
150 flag-sightings of Australian birds during the last northwards migration
season. With that kind of coverage, quite detailed analysis is possible: for
example we now know that the first Victorian Curlew Sandpipers get to Hong
Kong 10 days before birds start to turn up from north-west Australia.
Flag-spotting is even more fun if you happen to be wader-watching at a place
which is seldom visited by birders. I learned this in Siberia in 1994 -
Snowy Owls, Ross?s/Ivory/Sabines Gulls, breeding Long-billed Dowitchers and
the like were all very pleasant, but paled into insignificance compared to
the buzz I had on finding a yellow-flagged (north-west Australian)
Bar-tailed Godwit at Indigirka Delta - our first direct evidence that the
Bar-tailed Godwits in north-west Australia are subspecies menzbieri. Magic!
(if your tastes happen to run that way).
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