We spent the whole day at Esquinas. We did the usual early morning 6 AM walk on flat trails. After breakfast, we undertook a killer walk on Ocelot Trail, which climbs and winds up one of the limestone domes here on the valley floor. Geology in Costa Rica is famously complex. It's at the junction of numerous tectonic plates, and the interplay is difficult. Speculating freely, I'll guess that the Cocos Plate is or was subducting under the North American and Caribbean Plates in this immediate area. As it descends, some of the limestone-covered ocean bottom is jacked up and some is scraped off, creating a karst topography along this part of the country. A clue would be the numerous limestone quarries and cement manufactories along the highway. The steep-sided domes are areas that resisted chemical erosion by tropical rain, usually as a result of a cap of some more insoluble rock. So the topography is flat, with very steep limestone domes, some linked by ridges, to a height of maybe 1,500 feet above the valley floor.
The Ocelot Trail, according to Nick, was laid out by researchers, and climbs up and down for doubtlessly valid research reasons, but it is brutal to walk with temperatures in upper 80s and 99% humidity. Some good birds, including the endemic Black-faced Ant-Tanager. But we worked for them. It was especially hard on Mary Teel, who is still recovering from surgery. I went through a big bottle of water, after water, juice and coffee at breakfast, and never once peed. I was able to wring sweat out of my shirt afterwards, like a soaked dish rag. Nancy and I swam in the pool and took a long, cold shower to try to cool off. We napped under the room fan after lunch.
In the afternoon, we walked a couple of miles along a blessedly flat road to twilight, with excellent birds. Among them terrific views of the reclusive Great Curassow, a lifer.
Just after we got back to our rooms it started to rain and is coming down now in trademark tropical torrents. Some roof leaks, but none where it matters. Already some minor flooding. Hard work today, but a terrific day of birding.
|