Vava’u site information.

Of the 21 sites surveyed at Vava’u, the target coral species Pocillopora damicornis, or, alternatively, its closely related sister species P. acuta, was sampled from 10, and the data in this table are from these sites only (in addition to a “snorkel site” where only several minutes were spent). In total 61 pocilloporid corals were sampled, though neither species was observed at the following eight sites: TOVA36-38, 45–46, 48–50. For the following three sites, P. damicornis/P. acuta may have been present, but no colonies were sampled: TOVA41-43. For the environmental data for all 21 surveyed sites, please see S1 Data. All reefs were emergent unless noted otherwise. The average temperatures (temp.), salinities, and live coral cover (ALCC) percentages (±std. dev.) in the “Vava’u avg.±std. dev.” and “Tonga avg.±std. dev.” rows reflect the means across the 10 Vava’u and 25 Tongan (15 Ha’apai+10 Vava’u) sites from which corals were sampled (excluding the snorkel site at Vava’u, where none of these parameters were measured), respectively, and the temp. was significantly higher at Vava’u than at Ha’apai (student’s t-test, p<0.05). The 17 samples highlighted in bold were not processed for all molecular-scale response variables (MSRV). PM = P. meandrina. PV = P. verrucosa. ND = not determined.