The second picture shows the same bird scratching, which for some reason caused its crest to rise.
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I've never seen their crest looking like that. Great capture!
Sara Garcia Hipolito
I've added another picture, of a different bird this time, and in different circumstances; this time carrying nesting material into a tree.
I don't know why thy hold their crests up, and under what circumstances. Perhaps someone knows?
I thought Gey Herons used their necks and plumes when under threat or in aggression but that doesn't seem likely in your second picture. Perhaps it signifies the bliss of an itch scratched!
Certificate in Contemporary Science (Open)
Lat/Lng: 51.7987, -0.0053
OS grid ref: TL376129