The biter bit Mike!
A Donax could certainly exert great force.
I always enjoy watching Oystercatchers and I now have another reason to spend
more time doing so.
I haven't noticed Sooty Oystercatchers with missing feet. I assume they're
foraging on rock platforms and don't encounter bivalves.
Sent from my iPhone
On 21/02/2013, at 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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