Thanks Mike. I was a little skeptical about the fishing line/rubbish
explanation since it seemed unlikely to tangle so tightly as to cut off
circulation, or for birds when tangled to fly away with so much force as to
rip their feet off (not to say that could never happen).
Jeremy
On 21/02/2013 2:28 PM, "Mike Carter" <> wrote:
> 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.
>
> But there may be a more natural cause. The bivalves they seek to eat fight
> back by closing over their toes! David Melville, currently based in NZ is
> currently researching the phenomena for a paper after witnessing in China
> two Bar-tailed Godwits apparently trapped by clams. One remained motionless
> for over three minutes before escaping. He asked me for a copy of a note on
> the subject that I published in Australian Birding in Autumn 1999.
>
> This is the gist of the note. On 19 January 1999 on a beach at Ballina
> NSW, I saw an Australian Pied Oystercatcher (OZPO) that was foraging in the
> wash-zone suddenly leap into the air uttering a loud yelp. A 3-4 cm bivalve
> presumably a pipi Donax deltoides had clamped around one of its toes.
> Continuing to call and obviously in some distress it flew to a height of
> 1.5 m shaking its leg vigorously. This dislodged the pipi which fell into
> the sea. The OZPO landed on the dry beach supporting itself mainly on the
> unaffected leg, occasionally lifting and shaking the one that had been
> caught. After several minutes it resumed feeding normally. Three of the 52
> OZPOs on that beach were limping. According to Bo Totterman who studied the
> OZPOs there and incidentally had just found Australia's first South Island
> Pied Oystercatcher (SIPO), one bird known as 'Hoppy' had lost all its toes
> on one foot and the stub end of the other tarsus was clubbed. The other two
> limpers were not so badly disabled. He claimed that there was no evidence
> that the trauma had been caused by bands.
>
> Mike Carter
> 30 Canadian Bay Road
> Mount Eliza VIC 3930
> Tel (03) 9787 7136
>
>
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