Tight together by the tide

Last friday 16-feet tide was high enough to push all the shorebirds of Panama Viejo to a tiny piece of beach close to the road. When I got to the place, it was raining so I started to watch them with my binoculars, waiting for the rain to stop. I noticed a plump-shaped shorebird accompanying the flock of peeps, evidently larger than them and looking quite similar to a dowitcher, except for its short bill... it also behaved different. A closer look revealed it to be a basic-plumaged Red Knot, which is not often found there. The rain stopped so I left the car and started to approach the birds. The knot did not stay, but all the others shorebirds did, including the flock of Short-billed Dowitchers. I usually don't have these close encounters with the dowitchers, so I took all the photos I could, including the molting individual that still was exhibiting some juvenal feathers at the coverts and the tail (the third photo).But definitively, the main show was protagonized by the three peeps species. I have to say that in Panama, these birds show their alternate plumage just for a brief period of time. The Least Sandpiper is, perhaps, the most easily identified, with its yellow legs, the thin bill and darker back. The size per se is not a good field mark as you can see in the next photo. Also, they usually like to wander close to the grassy coast and to the mangroves, instead at the extensive tidal flats like the other two species.In basic plumage the Western and Semipalmated Sandpipers are very difficult to distinguish. The main field marks are bill lenght and shape. Other field marks, like body shape, grade of facial contrast and vocalizations are not easy to determine under usual viewing conditions. Even with close and careful observations, many sandpipers will be left unidentified. I can id for sure the extremes... that is, long-billed females Westerns' (almost always with an evident dropped tip of the bill) and short, straight-billed males Semipalmateds'. For example, the next three photos are Western Sandpipers (the last two photos of a juvenile molting into basic-plumaged adult?).And the next ones are of a Semipalmated Sandpiper.Bear in mind that both species can show the rufous tinge to the scapulars, so it is not a good field mark in Panama. That day, it seemed that most of the peeps present were Western Sandpipers.
The peeps were all tight together in the same flock, with the dowitchers and some plovers, specially Wilson's and Semipalmated Plovers, with few basic-plumaged Black-bellied Plovers among the multitudes.

In general, the big shorebirds were apart of the peeps. The exception were the Willets... they looked immense compared to the peeps surrounding them.

But my favorites were the Marbled Godwits. That bubblegum-pink bill is unreal.

Well, a typical day at the Panama Viejo's mudflats!