Reef mantas queueing at a coral cleaning station in 15m, you kneel on the sand and watch 3-4m animals hover overhead while…Reef mantas queueing at a coral cleaning station in 15m, you kneel on the sand and watch 3-4m animals hover overhead while cleaner wrasse work them over. One of the most reliable manta sites in Asia, and Ishigaki's coral is among Japan's healthiest. Kabira Bay is Japan's black pearl centre, cultivated since the 1960s. The manta population here has been individually catalogued by Japanese researchers for decades using belly-spot patterns. Ishigaki sits on the Sekisei Lagoon, the largest coral reef in Japan. Anchorage: Anchor in Kabira Bay, well sheltered, though pearl farms restrict some of it. Hazards: Typhoon season Jul-Oct. Boat traffic over the site; stay low and let the mantas come. More