The flag on this bird is actually DH.
It was ringed at Mai Po the night before you've photographed it on 14-Jan-2021.
And in your photo, you can see it is carrying a GPS tracker.
This bird has been foraging frequently in Nam Sang Wai in the past 3 weeks.
Katherine
Waterbirds Ringing Group
Welcome to HKBWS Forum 香港觀鳥會討論區 (http://www.hkbws.org.hk/BBS/)
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