WWF has produced a new documentary on the Madeira River:

http://www.worldwildlife.org/who/media/press/2010/WWFPresitem15303.html

Please also check out the latest installment of “Monster Fish” Monday August 2, 2o10 at 10pm.  The episode “Jungle Catfish” focuses on the Rio Roosevelt and Rio Madeira. 

Dr. Zeb Hogan teams up with experts to explore a forbidding 400-mile-long river: the Rio Roosevelt. They’ll have to navigate Class V rapids, avoid potentially violent tribesmen and survive in one of the most unforgiving places on the planet. The team hopes to find giant piranhas, painted catfish and perhaps even a new species of fish unknown to science.

Read more: http://channel.nationalgeographic.com/series/monster-fish/4767/Overview#ixzz0vRLn2ugf