25 species of Pigeons & Doves in Costa Rica
These birds are in the of order Columbiformes. Some are familiar to North Americans, while others are specialties of the tropics. They are unusual among birds because the parents secrete 'pigeon milk' in the crop (part of the esophagus), and this is the chicks' only food during their first days.
The milk is similar in constitution to mammalian milk but is thicker and also is produced by both sexes. The milk is regurgitated from the crop and the young eat it from the parent's mouth. After a few days, solid food is also regurgitated and mixed with the milk in increasing amounts. By the time the chicks fledge (about two weeks in small birds and over a month in large ones), milk is only a small portion of the regurgitated mixture.
The largest species is the 35cm-long band-tailed pigeon (paloma collareja; Columba tasoata), so called because of the dark gray band in its pale gray tail, but better identified by a white crescent on the back of its neck and a yellow bill. It is frequently seen in flocks in the mountains above 900m.
There are several small ground-doves, of which the most common is the ruddy ground-dove (tortolita colorada; Columbina talpacoti). The male is reddish, distinguishing it from other ground-doves. It has a pale gray head and almost white throat. It prefers open habitat and is often seen in agricultural country and along roads below 1400m on both slopes. As the name implies, these birds spend much of the time on the ground, foraging for seeds, berries, and possibly insects and other small invertebrates.
Pigeons and doves generally have cooing calls. One of the most distinctive is that of the short-billed pigeon (paloma piquicorta; Columba nigrirostris), which sounds like 'cu-COO cucoa: accented on the second and fourth notes, and is frequently heard from the middle and upper layers of humid forests up to about 1400m.