I do not want to start up a debate about the pros and cons of banding, as
that has happened too often on this site, but I can't leave Mike's Carter's
assertion that bird bands and clams are the major cause of toe loss in
Oystercatchers unchallenged. Firstly bands are placed on the tarsus or
tibia of oystercatchers where they would have no effect on the toes of the
birds. Clams/pipis may be the cause but fishing line is also a real threat.
I am aware of a number of incidents where fishing line has caused damage to,
or the loss of, an oystercatcher's leg. In one case the bird was not banded
and in another the bird was carrying a numbered metal bird on one tibia
(above the joint) and a flag on the other tibia. The bird with the band and
flag only had fishing line on the lower legs and there was none tangled
around the band. Despite this it was implied that the flag had caused the
problem. Once a bird is banded or flagged it is convenient to blame the
banding/flagging for any injury that befalls the bird even when it is
clearly not the case. I know of no proven case of a band or a flag
injuring the leg or legs of oystercatchers. Mike's observation of an
oystercatcher carrying a number of bands would relate to the former practice
of placing one numbered stainless steel band, along with a number of colour
bands, usually made of plastic or similar, on both legs. This was the case
in Victoria and birds carrying these bands have been recorded as far from
the banding site as the Northern Rivers of New South Wales, where no
inconvenience was observed. Despite this it is now usual practice to place
only one numbered stainless steel band on one tibia and an engraved flag on
the other tibia, thus reducing the number of bands used. It is most
unlikely that Mike's limping oystercatcher was limping because of the bands.
It may have injured its leg in a number of ways including being caught in a
clam or pipi shell, being hit by a vehicle, flying into powerlines, being
attacked by a dog or fox etc, etc. I am disappointed that banding has, once
again, been blamed for injury to birds without the necessary evidence to
support the claim. The extraordinarily high number of flag sightings of
Pied Oystercatchers that I have banded and flagged on the NSW north coast at
places such as Stradbroke Island, Queensland, and at Sydney and the south
coast of New South Wales indicates that most young oystercatchers that are
banded and flagged survive to an adult age despite the many natural and
unnatural threats that they have to endure. Please, if anyone has
documented evidence that shows that bands or flags have injured or are
injuring oystercatchers please provide it to me as the aim of the banding is
to assist in the conservation of a threatened species and not to harm it.
But please I need evidence and not ill informed opinion.
Greg
Dr Greg. P. Clancy
Ecologist and Birding-wildlife Guide
PO Box 63 Coutts Crossing NSW 2460
0266493153 0429601960
-----Original Message-----
From: Mike Carter
Sent: Thursday, February 21, 2013 2:28 PM
To: David Clark ; Jude Latt
Cc:
Subject: Short Pied Oystercatcher
Although fishing line and hooks cause the maiming and deaths of many birds I
do not think it likely that it is the major cause of toe loss in
Oystercatchers. I suggest two other causes, bird bands and clams are to
blame. I've often seen Oystercatchers belaboured by up to five bands limping
badly. Because of this many years ago the Rangers on French Island here in
Victoria were reluctant to grant and possibly refused permission to band
Oystercatchers there.
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