Belcher's Gull [sic], Kelp Gull at Costa del Este
[The bird in question was proven to be but a subadult Kelp Gull. Apologies]
Euclides Campos and Ramiro Duque visited Costa del Este today and found not only the Belcher's Gull [sic], but an adult Kelp Gull, plus the third-winter Lesser Black-backed Gull first photographed at the end of february and a Herring Gull. In the photo above, the gull in front shows a white mirror on what we presume is P10 and a white tail, which could show it to be an adult Kelp Gull, while the one in the back may show a black tail and no mirrors on the tips of the primaries, but they're roughly the same size. A Belcher's Gull should be noticeably smaller, so maybe it's another Kelp. More details to come.
Euclides Campos and Ramiro Duque visited Costa del Este today and found not only the Belcher's Gull [sic], but an adult Kelp Gull, plus the third-winter Lesser Black-backed Gull first photographed at the end of february and a Herring Gull. In the photo above, the gull in front shows a white mirror on what we presume is P10 and a white tail, which could show it to be an adult Kelp Gull, while the one in the back may show a black tail and no mirrors on the tips of the primaries, but they're roughly the same size. A Belcher's Gull should be noticeably smaller, so maybe it's another Kelp. More details to come.
And now more photos, labeled for your convenience. 
(Belcher's Gull [sic])
(Kelp Gull)
(Lesser Black-backed Gull)
As a bonus, he sent this photo of an unfortunate Yellow-breasted Crake being devoured at Las Macanas Marsh on March 3, where he also found a group of Long-billed Dowitchers (identified by call).
