To find and catch river-dwelling fish, you need to think like one. Here’s how

NEEDS

At almost all times, trout, bass and other fish in moving water are balancing three demands. The first is shelter from the current. A fish holding in strong current would die of exhaustion in hours, just like a person trying to run uphill all day. The first sign of a fish-holding spot is where the current slows: behind an obstacle, against the bank, or simply along the bottom.

Fish also need protection from predators, primarily the beaks and talons of birds. Deep spots offer that, as does broken water, since a churning surface is hard to see through from above.

Finally, fish need to eat. That requires a place where current—ideally faster than in their holding spot—regularly delivers food. However, hunger can override other needs. When forage, especially hatching insects, are very plentiful, fish will abandon safe, comfortable spots, and move into more exposed ones. They’re gambling that the increased risk is worth the easy calories.