Originally posted by pete-tarmigan Given that both of these species' plumages vary due to plumage polymorphism and age, you might have to consult James Ferguson-Lees' and David A. Christie's book: Raptors of the World, first published in 2001. Published in North America by Princeton University Press, and in the UK, by Christopher Helm.
Thank you for that direction, though I am fairly confident that my ID is correct, having consulted all the bird books I have, including Roberts Birds of SA, the standard reference work around here. Several other raptors have been excluded such as Booted Eagle, Lesser Spotted Eagle and the Steppe Eagle. Here is a Wahlberg Eagle, some differences noticeable
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