Nyctibius griseus (Caprimulgiformes - Nyctibiidae) is a large nocturnal bird of lowland forests and forest edges of southern Central America and central and northern South America.
Nyctibius griseus is commonly named Common Potoo in English, or Nictibio urutaú, Nictibio, Urutaú común, Pájaro fantasma, Biemparado norteño, Pájaro estaca menor o Estaquero común, in Spanish. Many of these regional names allude to its distinctive way of perching on branches or trunks, with head erect and completely immobile.
During the day, Common Potoos usually roost on snags, exposed branches or fenceposts, where their disruptive coloration helps them remain avoid detection. Have you been able to easily distinguish the two birds - mother and chick - in the picture?
They forage at night by sallying from exposed perches to catch flying insects. Common Potoos most frequently are detected by their amazingly haunting, descending song [listen here]. They also can be located at night with a spotlight by searching for eyeshine at the tops of exposed perches.
Common Potoos lay only a single egg, and do not build a nest; the egg is nestled on top of a stump or a broken branch, or in a slight depression on a large tree limb.
This potoo is a large cypselomorph bird related to the nightjars and frogmouths,
but like other potoos it lacks the bristles around the mouth found in
the true nightjars. It is 40 cm long and pale greyish to brown,
finely patterned with black and buff, camouflaged to look like a log; this is a safety measure to help protect it from predators, but its mode of perch is also a camouflage. It has large orange eyes.
The common potoo can be located at night by the reflection of light
from its eyes as it sits on a post, or by its haunting melancholic song,
a BO-OU, BO-ou, bo-ou, bo-ou, bo-ou, bo-ou, bo-ou, bo-ou dropping in both pitch and volume.It has special disruptive coloration so it camouflages into a branch.
This nocturnal insectivore hunts from a perch like a shrike or flycatcher.
During the day it perches upright on a tree stump, and is completely
invisible, looking like part of the stump because it stays so completely
still as it perches. If disturbed by larger animals, such as common marmosets (Callithrix jacchus), it may break its camouflage and try to chase them away however.
The single egg is white with lilac spots. It is laid directly in a depression in a tree limb, usually some meters above ground. It is not clear whether there can be, on occasion, two eggs in a clutch.