On Thu, 11 Aug 2005 16:21:43 +1000, Bruce Robertson <>
wrote:
From the close-up image of the head of this bird, it appears to me as
though
the iris of the eye is possibly a yellowish colour. I agree that it
appears
as though there is not much, if any, speckling in the iris of the eye -
just
a basic background yellow colour.
Another point to consider here is that there are a number of medical
conditions that can affect the colour of the eye e.g. hyper-lipaemia and
jaundice to name just two. Physical injury can also affect eye colour.
Bleeding into the anterior chamber of the eye, a condition called
hyphaema,
can also cause the eye to appear very dark in colour. The pupil here is
easily visible and appears normal, so I do not suspect any conditions
like
lens luxation etc.
Bruce,
Thanks for all you help. I am no expert so any of this info will be
helpful for me in the future. Both eyes are actually this colour, but
I guess a medical condition may affect both eyes.
APart from iris colour, can you tell me what the features that distinguish
georgii from pacificus? What is it about the loral feathers around the
bill,
billshape, amount of red on mill and orbital ring colour that is different?
RE: Bill shape. This bird seems to have less gonydeal angle than normal,
making
the bill less bulbous, but I am not sure how that affects this gulls. I
believe
it is usually used to identify birds in the northern hemisphere and is
sometimes
more reliable than plumage, eg. Caspian Gull.
Regards,
Vin.
--
Vin Lam, Melbourne Australia
bird count : 446
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