As the sun sets over the Western skies of the Upper Amazonian rainforest, something quite magical occurs. The sky may be a glorious riot of colors which gradually give way to darkness. Darkness, like many people have never seen as there are no city lights to obscure the sky and very soon after dark it is obvious there are a trillion stars in the sky. Amazingly, constellations that may be most familiar to us are not apparent. Not only because we are now just south of the Equator, so the constellations of the southern hemisphere are quite different, but also because there are so many stars, it is considerably more difficult to distinguish constellations. Darkness is what it is supposed to be like…DARK!
Along with darkness comes a changing of the guard. The day time chorus of birds, the whistles of tamarins and the rhythmic cadence of cicadas gradually cease as these creatures go to roost. There is a very brief period of time when the rainforest is almost silent. This certainly does not last long and soon the first katydids begin calling and from emergent vegetation come the amazing buzz, whistles, cacks, trills, snores and croaks of a tremendous number of frogs. Incredibly, there are more species of frogs in the Amazon area of Iquitos than there are in all of North America. If a strange sound is heard, you can say it is a frog and in all probability you would be correct. This nocturnal serenade can only be appreciated “in person” during an excursion as part of IE's Amazon cruise. It is extremely difficult to describe the amazing diversity of sounds that are emitted from the darkness of the Amazon.
As if this is not enough, there are a few other sounds that typify the rainforest. The strange screeching of the world’s only nocturnal monkey…the owl monkey; the almost human like scream of the bamboo rat; and the eerie call of the potoo. The potoo is not an owl but instead they are a member of the Frogmouth family of birds. Their preferred perch is at the top of a broken off tree where they appear like an extension of the tree. In the beam of a spotlight, the eyes of the potoo appear like bright red embers. Almost crocodilian like in reflective shine but crocodiles do not climb up into the trees and potoos do not sit in the water, so the location of the eye-shine is very important in identifying the brilliant red embers in the shine of a light.
These then are just a few of the many sounds of the nocturnal serenade you'll find during our Amazonian rainforest tour. The best way to experience this is by excursion boat into one of the smaller tributaries feeding the mighty Amazon. From the safety of the small boat and entirely new world will open before your eyes and EARS!
Naturalist Greg Greer  is a favorite among IE travelers, and has gained a reputation for his friendliness and good humor, along with his incomparable knowledge of natural history, photos and articles have been widely published in books and magazines, including Georgia Outdoor News, Bird Watcher’s Digest, Alabama Outdoor News, Riversedge and Southern Wildlife.