The bare throat patch is something I have used for some time. While not always visible, its presence does confirm that the bird is an Australian Raven. Video linked below is of an immature bird showing the throat
patch.
http://www.hbw.com/ibc/1198517
From: Geoffrey
Dabb [
Sent: Saturday, 10 June 2017 6:08 PM
To:
Subject: [canberrabirds] Thoughts on the 2 local ravens (1)
This is prompted by a close look at the recent ‘Australian Bird Guide’. With respect to head/neck features of the Australian Raven, this says:
<< obvious long throat hackles … forming a beard reaching upper breast, especially when expanded while calling.
Ad. … iris white with pale blue inner ring: Crown rather flat ; bill long and heavy; black bare skin on base of lower mandible extends back to the sides of the chin forming a gular pouch. >>
The illustrations seem to me to be quite good in showing the difference from the Little Raven (discussed in a second message), without creating unrealistic caricatures in order to bring out the differences. However there is an annotation:
<< bare rectangular skin patch on side of chin >>
A slightly greyish patch can just be discerned in the illustrations that might be intended to represent bare skin. I had not myself noticed this in birds in the field, so I went through a few photos. I found a couple where it can be seen,
but I believe it is generally obscured by feathers, so I wonder about its usefulness as a field mark. I would not myself describe it as ‘rectangular’.
The bills are good in ABG, showing the A Rav as slightly but distinctly thicker from the side. The Nicholas Day illustrations in HANZAB show the A Rav bills as longer, but no thicker than the Little Raven. Head shape is good though.
