We spent the morning of Monday, January 16, 2012, birding along Yarapa Creek, a tributary of the Amazon (South Bank). We were at the junction of where the Yarapa (blackwater, foreground) and the Ucayali (whitewater, silty water running down from the Andes, background) meet. Temperatures were in the low 80's on this humid morning with hazy skies and high humidity. A blackwater river has a deep, slow-moving channel that flows through forested swamps or wetlands that picks up tannins from decaying vegetation. The acidic water becomes darkly stained. Most major blackwater rivers are found in the Amazon River system and in the Southern United States. Whitewater rivers are higher in nutrients and have ionic concentrations that are higher than rainwater. Flora and fauna in each area differs. Where blackwater and whitewater combine, such as along the Yarapa and Ucayali, respectively, a diverse blending of types of organisms can occur.


Yarapa_Ucayali_A.jpg
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generated by EXIF-O-Matic on 2013.6.29