Rich Hoyer on birding in Costa Rica
The birding in the Arenal area can be really good. The center of the
birding area is essentially the road that cross the dam of Arenal
Reservoir. The few kilometers in either direction of the dam can be
very birdy. The side road on the downstream (Fortuna) side of the dam
can be worthwhile, especially the level stretch above the little guard
station. This is where birders have seen the elusive Keel-billed
Motmot.
If you can manage to stay in the Puerto Viejo area, it would be worth
your time to schedule a full day at La Selva. They have resident guides who take you on the trail system, and you'll be guaranteed a big list
of birds that you won't get elsewhere.
Another great area is Carara National Park, which you pass on your way
to Manuel Antonio. There's a small trail system in the forest as well
as the Laguna Meandrica trail/road that goes through level, seasonally
flooded forest that can be teeming with birds. Get your Black-bellied
Wren here! And then there's the mangroves by the river mouth where you
can go with Luis Campos on a boat ride and find some great birds like
the endemic Mangrove Hummingbird. The lodge to stay at here is Selva Verde.