The series of ponds at Reserva Las Brisas near La Alegría de Siquirres in Limón Province is a great spot for close observation of the resident Least Grebe (Tachybaptus dominicus), the smallest grebe species in the Americas. In Costa Rica it is the smallest swimming water-bird. It is found from southern Texas to Argentina but Cornell University notes that it is little studied because of its secretive habits.

Adult Least Grebe with its yellow eye. Photo by John Beer
We found as many as 5 individuals, one of which was this immature bird with its striped cheek, a feature not shown in Garrigues and Dean‘s standard Costa Rican field guide, The Birds of Costa Rica:

This young Least Grebe was accompanied by one adult. Photo by John Beer
A final beautiful image of an adult bird:

Small but very beautiful, the Least Grebe, courtesy of John Beer