I’ve written (and routinely update) this article so that (1) it’s easy to refer people with questions about the gear I use, and how I set it up, and (2) I can remember what settings I use, too.

Frame-by-frame video analysis reveals the sharks’ strategy. They lunge forward, then use their big wide pectoral fins to hit the brakes. This stalls their whole body, allowing them to deliver an overhead tail-slap at measured speeds of over 20 meters per second (45 miles per hour). That’s so fast that the tip of the tail literally causes water to bubble.

After a few days on Isabela Island on a wildlife-watching trip (photos to come), we flew over to San Cristobal on a small plane. We wandered down to the “Hammerhead Pier” early the next afternoon and were met by one of the dive guides from the Humboldt Explorer and transferred out to the boat. It was great to see a few familiar faces from past trips, and lots of new ones!