The Clay-colored Robin (Turdus grayi) is the national bird of Costa Rica, and one of the most widespread . I don't think there was any major area without this bird. The local name is "Yigüirro" and the song signals the beginning of the rainy (and therefore, the planting) season.
Clay-colored Robin (Turdus grayi). This I call the "Mono-Duet", a double call in which the bird uses both syrinxes to make slightly different sounds - it took me a while to figure out that this wasn't two birds duetting.
Clay-colored Robin (Turdus grayi). In this sample they use this "mono-duet" as a mobbing call as they harrass a pair of Spectacled Owls that are too close in the river bottom at El Gavilan, near Puerto Viejo de Sarapiqui 6/20/99.