When an unsuspecting grasshopper jumped in the water, the water exploded like a pool of piranha. So...I would suggest a bait to emulate a grasshopper.
The year I moved here it was so dry and hot and we were having a grasshopper population explosion of biblical proportion... I went to Wallowa Lake and rigged up grasshoppers on a floating fly line cast from one of the water ski docks and caught a limit of huge trout.