Every Woodpigeon I've seen seems to have an irregular shape to the pupil of the eye. Is it known if there is a beneficial or other reason for this?
My bird photos HERE
All I know Paul is that they have the most exceptional eye-sight and even when we are inside the house behind the window they can detect you are there and the slightest movement (even when a metre or so from the window) so those eyes must give them incredible super vision.
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Regards, Hazel
Hi Paul, I am in regular contact with Hein van Grouw, Senior Curator, Bird Group at the Natural History Museum, so I e-mailed him. This is his reply:
Thanks for your email. Yes, wood pigeons seem to have non-circular pupils. The pupil, however is circular but due to a spot of dark pigment in the iris the pupil seems to be non-circular. I have no idea what the reason (advantage) is for this. What I do know is that several other (tropical) species, mainly Fruit Doves, have it too.
Unicum arbustum haud alit duos erithacos
(One bush does not shelter two Robins)
Zenodotus (3rd Century B.C.)
It was very perceptive of you to note that, Paul. I don't usually photograph Woodpigeons so I thought I'd see if one of mine exhibited the same feature.
Sure enough it does. Thanks to the other Paul for getting an expert from the NHM to explain. I would have assumed it was a non circular pupil rather than a dark mark on the iris. You learn something new everyday.
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Tony
My Flickr Photostream
Thanks MC, it was very kind of you to go to the trouble of finding this out. I’ve often seen Woodpigeons making abrupt course changes from way out so I always knew that they had fantastic eyesight. It’s actually quite comforting to know that no-one seems to be sure of the reason behind the pigmentation in the iris, I think the world would possibly be far worse off if there were no mysteries left for us to wonder at. :-)
Just as a point of interest, I’ve also noticed that Oystercatchers seem to have the same feature in their eyes.
Interesting. Trim that beak in your last inset pic and you have a Pigeon...
Interesting Paul, I hadn't realised they had the similarities of the pupil to the woodpigeon. I've been googling = take a look HERE
and for Paul (MC) here's info about feral eyes/ colour, etc. HERE
Very interesting, Hazel. I wonder if this applies to 'our' Oystercatchers as well?
I imagine it would apply to UK species but we'll have to wait for Aiki or one of our birdy experts to see what their opinion is, there's still such a lot we don't know about birds ! Not sure there is a definitive answer to the shape of the pupils so will be interesting if anyone finds out more info.
I know that frogs & toads have eyes that go different ways & that it helps to identify them. Interesting info on birds eyes. Gulls are often odd colours too.
Best wishes
Hazel in Southwest France