At 11:57 AM 19/07/1999 +1000, you wrote:
>The albinistic individual was all off-white except for dark eyes and
normally coloured black and chestnut breast bands.Head,back,wings and tail
were all offwhite.It was actively running around like the others but would
be chased off if it went too close to one of the others.It stood out on the
dark bank and amongst the other birds.On a sandy bank it would have been
inconspicuous.
>
> Michael & penny Hunter.
Michael and Penny,
Since this bird had a dark eye, it was probably not albinistic. Albinism is
the complete absence of colour, hence albinos have pink eyes (and bills and
legs). Two other pale coloured abberations that are recorded in birds (and
may refer to what you saw) are isabelline and leucistic. Unfortunately, I
don't have any papers on these at hand, but breifly, in isabelline penguins
the normal colour pattern is present but very washed out (yellow-grey in
colour). Leucistic may refer to being completely white (as in leucocytes -
white blood cells), but I am not sure.
But beyond the difficulty of definition, I was interested to hear of this
record, as there has been an abberant Double-banded Plover (isabelline by my
above definition) at South-Arm Neck (in southeastern Tasmania) for the last
two weeks. This bird has a washed out sandy colour, instead of the normal
brown, to its upperparts and head. It has a single, very washed out, breast
band (the upper one).
It would be interesting to find out how often these occur in DbPs, and what
their survival chances are (for example, small numbers of them occur in shy
albatrosses, but they almost never survive).
tim.
===========================================
Tim Reid.
Marine Conservation Section
Tasmanian Parks and Wildlife Service
PO Box 44a
Hobart
Tasmania
Australia
phone: 011-61-3-62336018
fax: 011-61-3-62333477
e-mail:
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