Nice photos, but note that the other bird on the first photo is a pintail (not wigeon as it says in the caption). Note the sandy plmage, gingery head and patterned body. Wigeon would be plainer and darker, with a short pale-grey bill.
Note also that the bird on the right of the first photo is a male garganey, not yet in breeding plumage. There is an obvious grey feather visible on the flanks and browner feathers moulting into the head pattern.
There are some very nice male garganeys (full breeding plumage) present at Mai Po at the moment
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