Potential larval sources, destinations, and self-seeding in the Mariana Archipelago documented using ocean drifters

Identifying transport pathways and sources of reef larvae is an essential component of ecosystem science. Ocean drifters tracked by satellite around the Mariana Archipelago were used to evaluate the possible pathways of transport among islands for passive larvae of reef organisms present in the surface layer. Reef taxa vary in their minimum and maximum larval duration from several days to a few months. Drifters leaving the Marianas required more than 16 days of transport prior to arriving near any adjacent island groups. Drifters arriving at the Marianas required more than 35 days of transport before being tracked back to any adjacent island groups. All arrived from the east or southeast via the North Equatorial Current. Roughly 27 % of the drifters that began in the Marianas returned. The majority of returning drifters (65 %) ended to the north of their starting point. Over 70 % of the drifters that returned to the Marianas after starting there did so in less than 40 days. Overall, this suggests that self-seeding may be of great importance to sustaining Mariana reef populations and that position within the archipelago affects connectivity among islands.