has anyone else read the book "Cataract Canyon: A Human and Environmental History of the Rivers in Canyonlands"? Published by the University of Utah Press, click here
for more info.
if you havent, i would suggest at least looking at a copy, its fantastic! geology, biology, history, geography, its all in there, and lots of matched photos from the 1800's through today. truly a great resource on such a magical place