Bill and Chet were striper fishing in a boat off Nantucket. They noticed a local guide’s boat bobbing quietly in the near distance. (They liked to “shadow” the local guide, after all, he made his living by knowing where the fish were.) Nobody on the guide boat was fishing, they were taking a break. After a while Chet and Bill noticed flocks of birds starting to collect about 100 yards down-current from the other boat, but the guide slowly puttered away. Suddenly, Chet noticed an oily slick on the water. The birds started swooping and crashing on the surface. “Bunker bust!” Chet said, and Bill motored over to the spot. “Man, I can’t believe those guys missed this one!” Bill laughed. Together, they made dozens of frenzied casts, but only hooked a small chopper bluefish. Meanwhile, they looked up the shoreline, and Mr. Guide had both clients hooked up on stripers. What happened?