Manuel Antonio NP
Manuel Antonio National Park is a beautiful west-central park with several hotels nearby overlooking the ocean. Within the national park, there is a reasonable trail for general natural history that is guaranteed to be crowded with tourists. The park itself is not well-known for its birding. However, you are close to other birdy areas just outside the park like Esquipulas (Pacific foothill rainforest) and El Rey (coastal marsh). Both Esquipulas and El Rey are better explored with a birding guide. Johan Chaves, who leads tours in the area, is my recommendation (see my section on "Guides").
There are a few birds that can be found rather easily along some of the forested slopes around the area hotels. Black-hooded Antshrike and Chestnut-backed Antbird are fairly common in much of the understory depending on the hotel grounds. Fiery-billed Aracari is uncommon but sometimes seen around hotels like Costa Verde. Golden-naped Woodpecker is infrequently seen around hotels and on the park trail.
Olivaceous Piculet - Greg Lavaty
Esquipulas - Jim Peterson
Esquipulas is the name of a small community about 20 minutes east of the park in the foothills. This area has access to some very good rainforest along an unpaved road.
In about a 3-hour time frame with my guide's help, I saw birds like King Vulture, Short-tailed Hawk, White Hawk, Black Hawk-Eagle, Laughing Falcon, Fiery-billed Aracari, Charming Hummingbird, Purple-crowned Fairy, Olivaceous Piculet, Yellow-crowned Tyrannulet, Southern Beardless Tyrannulet, Bright-rumped Attila, Ruddy-tailed Flycatcher, Rufous-tailed Jacamar, Buff-throated Foliage-Gleaner, Rufous Piha, Turquoise Cotinga, Blue-crowned Manakin, Black-bellied Wren, Gray-crowned Yellowthroat, Shining Honeycreeper, Blue Dacnis, and Spot-crowned Euphonia. With Johan Chaves guiding, this area proved to be very good spot for Pacific rainforest birding. Most of my checklist birds from Manuel Antonio (classified as "MA" in the checklist) come from Esquipulas.
Riverside Wren - Greg Lavaty
Chestnut-backed Antbird - Greg Lavaty