Ocean Predators

Andy Dehart, Discovery Channel's shark adviser, holds on as a lemon shark clamps down on a piece of bait. "Shark Week," Discovery Channel's much-ballyhooed annual look at the lives of sharks, begins Aug. 2, 2009. "Blood in the Water," "Day of the Shark 2" and "Great White Appetite" are among this year's six new original programs. (The Discovery Channel )