Subtitles section Play video Print subtitles NARRATOR: Researchers have confirmed 100 bull shark attacks. But the real number may be much higher because the bull shark is so difficult to identify. When you first look at a bull shark, it doesn't really jump out at you that it's a bull shark. It just kind of looks like other sharks. You have kind of grayish brown on top, white below. That's really different from an iconic species like the tiger shark that has that really square head and those stripes that set it apart from any other species. And then you also have white sharks. Nobody's going to mistake a white shark. This is a really iconic look. You have the torpedo shape, the tail, the bright white belly, slate gray above. NARRATOR: The bull shark's looks aren't showy or iconic. But if you know what to look for, you'll never forget it. When you really start to look closer at the bull sharks, you see some features that differ from typical shark shape. They almost look like swimming mounds in time. They're really thick from those pectoral fins forward, huge jaws. And then, they've got the musculature to back that up.