Venezuela's Orinoco River

Unhalted by a dam anywhere on its 1,300-mile [2,092-kilometer] course, the Orinoco [shown above at its delta] floods annually and prodigiously. When the rainy Venezuelan 'winter' arrives, lasting from May through November, the river rises more than 40 feet [12 meters], drowning grazing lands miles from its low-water line. Labored wingbeats lift scarlet ibises from the llanos, the vast grasslands of Venezuela's interior A dying fire fends off the dawn chill in a Yanomami village near Venezuela's border with Brazil. Harder to repel are sporadic assaults by Brazilian gold miners, who in the summer of 1993 killed at least 16 Yanomami. Many more die each year from malaria and other diseases brought by outsiders. The rhythms of flood and drought regulate the pulse of life on [Venezuela's interior grasslands]. Coiled on a termite mound, an anaconda claims one of the few pieces of high ground left during the wet season, when an Orinoco tributary jumped its banks and flooded the grasslands for miles. Emerging at dusk to hunt, a burrowing owl is no threat to a capybara, the world's largest rodent. Resembling a cross between a guinea pig and a hippopotamus, the web-footed 'water hog' may grow to 140 pounds [52 kilograms] and stand knee-high to a man. Its mortal enemies include jaguars, caimans, and cowboys. From NGC .