Scientists are not entirely sure why spinner dolphins spin, but they have some ideas. The spinning and splashing might help the dolphins communicate with each other — different spin patterns could carry different messages, like a kind of aerial morse code. Other theories suggest spinning simply feels good or helps knock off tiny fish parasites. Whatever the reason, watching a group of spinners leaping together is an unforgettable sight.
Spinner dolphins are highly social and live in pods of up to 1,000 individuals, though smaller groups of 20 to 100 are most common around Kiribati's atolls. They cooperate to herd shoals of fish into tight 'bait balls', then take turns rushing through to feed. At night they move into deeper water to hunt fish that migrate upward after dark.
By day, spinner dolphins often rest in shallow lagoons, drifting slowly and breathing together in a sleepy rhythm. Children who live on the atolls sometimes spot them resting in the blue lagoon water near shore. In Kiribati tradition, dolphins swimming near your canoe is considered a good sign for a fishing trip.