Bill Clark wrote me today:
I have looked at hundreds of museum specimens of this and other
Circaetus taxa in numerous museums world-wide. I have seen juvenile BBSE
in various stages of moult into the next plumage. All show a dark
brown to rufous hood on the breast and dark spots on the belly, but
differ from Short-toed SE's in their secondaries, which are unmarked on
retained juvenile feathers and boldly barred on new ones. All of these were
collected within the breeding range of BBSE. No STSE's showed similar
secondaries. In fact, second plumage STSE's are characterized by whitish
heads and lack the dark breast.
See also:
Clark, W. S. 1999. Plumage differences and taxonomic status of three
similar Circaetus snake-eagles. Bull. BOC:119:56-59.
Bill Clark's latest comments
Bill Clark wrote me today:
I have looked at hundreds of museum specimens of this and other
Circaetus taxa in numerous museums world-wide. I have seen juvenile BBSE
in various stages of moult into the next plumage. All show a dark
brown to rufous hood on the breast and dark spots on the belly, but
differ from Short-toed SE's in their secondaries, which are unmarked on
retained juvenile feathers and boldly barred on new ones. All of these were
collected within the breeding range of BBSE. No STSE's showed similar
secondaries. In fact, second plumage STSE's are characterized by whitish
heads and lack the dark breast.
See also:
Clark, W. S. 1999. Plumage differences and taxonomic status of three
similar Circaetus snake-eagles. Bull. BOC:119:56-59.