If you’re being attacked, you probably don’t care which shark species it is doing the attacking. If you’re a photographer (and at a safe shooting distance), you do. The Blacktip Shark and Spinner Shark are very similar in size, shape, and markings. If being a juvenile isn’t a factor, we’re going with Blacktip Shark on this one, as the dorsal fin appears to begin before the pectoral fins end. A Spinner Shark would have the dorsal beginning behind the pectorals. This image was captured at the boardwalk behind Kiplinger Preserve, meaning this shark was in the St. Lucie River.