I have both a male and a female senegal, colour wise they look almost exactly alike there is no difference between the size of the v and also no difference in the amount of green/yellow at the tail. Despite this I am almost always able to tell them apart, even from a distance.
These are the differences that I have found between them, you could always use this a checklist to see if your senegal fits into this category (if there are any fail safe diffrences to look out for):
A. The female has a yellow dot on each shoulder, the male does not.
B. The female has light pink feet whereas the male has dark purple-ish feet.
C. The female has a very light grey head, the male's looks much more black.
D. The female's eyes appear slightly smaller and generally half closed (calmer/sleepy sort of look) and are pale yellow, the male's eyes are very big and wide (suprised/angrier sort of look), coloured a dark strong yellow.
E. The female's beak is smaller than the male's and resembles that of a green cheek conure, the lower mandible is noteably shorter than the top mandible, preventing her from giving an overly vicious bite, the male's beak is bigger than the female's and somewhat resembles that of a cockatoo, both top and lower mandibles are similar length, (the lower mandible still being the shorter of the two but not by much).
F. Males tend perch with their bodies in a bolt upright position, whereas females tend to perch in a much more horizontal position, with their chest facing slightly downwards toward the perch.
G. The top of a female's head is rounded whereas the top of male's head seems to have more of a flat/square like appearance, sometimes causing them to have a somewhat angry expression.
H. The female is smaller, with the male having a bigger beak and a taller/ stockier body and a very slightly bigger head.

If you have a Senegal, please post the gender (if known) and all the letters (A to H) which fit them/ if you notice any differences which I have missed off add them on as I, J, e.t.c.

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