G'day everyone
I've been going over the points of separation between the
Frigatebirds we get (or are likely to get) and am a bit puzzled about
one thing. I'd assumed that Least showed the white bar on the
underwing in all plumages (I hadn't noticed any lacking this in my
observations, and the field guides show this) yet there is a photo in
the National Photographic Index (Seabirds, p.471) showing neat
plumage but no white 'armpit bar'. This bird also lacks a dark
throat, which I'd expect to be present in a Lesser Frigatebird at the
age this one looks. Is this a misidentified/mislabeled bird in the
photo (ie, is it Great Frigatebird) or are these two species harder to
tell apart than I thought?
Harrison's photographic guide shows a few photos of
immature/juvenile Lesser Frigatebirds all with the white line on the
underwing, and attaining the dark throat prior to adulthood.
Any comments/suggestions?
They're not that easy, Frigate (birds)
Niven
Refs:
Lindsey, T.R., 1986, The Seabirds of Australia, Angus & Robertson
Harrison, P, 1987, Seabirds of the World - A Photographic Guide,
Croom Helm.
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