Tropical Kingbird, Playa Esterillos Este, Costa Rica
I had time for one more walk down the beach. I read the previous evening that the beaches in this area were divided by "nature-rich estuaries" (!). I had to see for myself.
And indeed, I eventually came upon an outlet entering into a mangrove swamp. And there was our old friend, the spotted sandpiper, and our more distant friends, the whimbrel and the tri-colored heron
OK OK. I've got to say it. Here is the dirty secret of Costa Rican beaches, and maybe of Costa Rican birding in general. The bird you will encounter most--more than the tropical kingbird--which sits on every wire ever strung between two poles in this country--maybe even more than the raucous and ever-present great-tailed grackle--is the black vulture. Not only do you see them soaring wherever you go, they (in this area at least) are the dominant shore bird. They know exactly when the tide is receding and they stand around waiting for large dead things to wash up. Sometimes they are exceedingly lucky. I personally find the following image rather upsetting, but it is part of the beach scene here. They are also quite stubborn in protecting their carrion, and won't be budged by the casual beach walker. So, who will take on the black vulture? Check it out. Another common beach presence in this part of the country is the yellow-headed caracara (its cousin the crested caracara is also common, though I found it a little bit more shy). These black vultures might think they're safe, sitting on their palm perches waiting for the tide to change. But they didn't take account of this caracara pair who will have nothing to do with it. Watch them as they drive the black vultures away.
This scene continued for quite a while, though eventually the vultures got the message. Apparently, the caracara are also carrion feeders, so the vultures are not simply taking their perches, they are direct competitors for food.