visual sexing theory in African Grey Parrots

visual sexing theory in African Grey Parrots
Min teori om synlig kønsforskel hos Grå Jaco (rødhalet)
Psittacus e. erithacus

female/hun, BB Hope
photo Valerie Maplesmale/han, Jako Amigo
photo Thomas L Pilegaardfemale/hun, Gabby
photo Deborah Watkinsmale/han, Merlin
photo Maria MetzgerMore pictures below / flere billeder nederst

Look at your Grey's eye, watch it from the side. It is important that not only the head is turned, the whole body should be in profile, or close to it. Otherwise there easily can be misleading observations.

There is a fine thin black line around the whole eye, on the eyeball - following the inner edge of the eyelid. My theory is, that females have a fine thin line that is equal all the way around the eye - BUT the males have more black, like a tiny black triangle in the corner of the eye (closest to the beak) - or you could say that the line is thicker towards the beak.
Please notice that some males at the first glance (like for instance photo NR. 4 male/han Merlin) seem to have an equal line all the way round the eye. If you look at bit longer, this does change, and now you see the triangle or a broader line in the corner of the eye. It can change to and fro. A stressed/afraid male can somehow fixate his eye in the socket, so that the black line resemble the female line. Thus can wildcaught/shy males - or males that are handled without being used to it, be impossible/difficult to determine. A breeder told me, that she observed a wildcaught male, and even if he was not terribly shy, it took him more than five minutes to relax, and the triangle became visible.
The eye's of a female does not change. The thin line is the same all the time. Some females seem to have a tiny triangle like photo NR. 3 Gabby, but they also very often have kind of a tiny triangle towards the neck.
It has been know for many years that males generally/often have almond shaped eyes and that females have round eyes. This method is much easier to use, even for people not used to observing birds. This is NOT an attempt to replace DNA or surgical sexing, merely a method to use as a useful hint. I do it because African Greys interest me very much, and I would VERY much like to hear from YOU. Do you have DNA/surgically sexed Greys, even if you just have one, please send me a mail and tell me about your observations of your Grey/s compared to the photos. Please tell me how many males/females does match and how many males/females, that does not.
So far there is and very overwhelming majority that points in the direction, that I'm on to something here.
In November 2001 there were 246 AFG's in the material (incl. several Timneh's) and of those 94,30 % follow the theory. Most of those who do not follow are males, probably because they were stressed/afraid.

Great information LiquidIce
thank you for that

I found that very interesting indeed, i have a dna sexed female if you would look in my photobucket if there are any pics you need feel free to use them. I'm going to study her eye more carefully now. I was told about the females having a more oval shape around the eye but never about the eye itself. Thanks for a good read.