A puzzling (to me) juvenile "Charadrius" plover with a hindcollar, seen in front of Mai Po's boardwalk hide on 31st May 2011.
The hindcollar should eliminate Greater and Lesser Sand Plovers, and these don't usually return to Hong Kong in juvenile plumages until late july.
Little-ringed Plover seemed a possibility, it breeds locally, but I eliminated it due to LRP's smaller size, brighter yellow legs and -usually- LRP's complete collar across the breast.
Common Ringed Plover and Long-billed Plover are both rare winter visitors. Neither seemed "right" for this individual.
Kentish Plover - is a spring and autumn migrant, numerous winter visitor - to my mind more delicate than this.
So I was still guessing about the identification until I heard that the recently re-discovered "dealbatus" form of Kentish Plover, known as "White-faced" Plover was found breeding on a beach in late May at Shantou, Guangdong Province, by Brian Ivon Jones.
For photos of young plovers on the beach, and other shots of "dealbatus" see Oriental Bird Images at :
There is a good online account of the re-discovery of "dealbatus" by Peter Kennerley and David Bakewell here at Surfbirds :
To sum up, "dealbatus" is:
(1) slightly larger than the Kentish Plovers that winter in south China,
(2) bigger-billed and
(3) longer-legged, especially above the knee.
(4) the legs are paler in colour than wintering Kentish Plovers.
(5) in flight: broad white trailing edge to secondaries, pale tips to the outer greater coverts and extreme white in outer rectrices, more so than Kentish would show (see below).
I may be guilty of making 2 + 2 = 5, but I think this could be a "White-faced" Plover, Charadrius (alexandrinus) dealbatus.
Science has not yet determined whether this form is a race of Kentish Plover, or a separate species.
I have exchanged Emails and my photos above with Peter Kennerley and David Bakewell - the co-authors of the "dealbatus" identification papers in Forktail and Birding Asia, as well as the Surfbirds article linked to above.
They have been quite positive, but have expressed reservations about whether these photos absolutely confirm the identification, especially because the identification features of juvenile "dealbatus" are still not well known.
A weekend excursion to Shantou to study juvenile "dealbatus" is required !