It had been raining for days. And so, Phantom, my 90- foot custom steel explorer, and her crew left drizzly Shelter Bay, Panama, for her next adventure in the sunnier reaches of the southern Caribbean. On a nautical chart, the San Blas islands look like coconuts scattered across the shallow waters off Panama's Caribbean coast. Coming upon these islands by sea is always something of a dream to me. As we approach their coordinates on the chart, the water changes from the deep hues of open sea to the dreamy shades of teal and aquamarine. Dozens of idyllic, palm-covered islands begin to appear across the horizon and it seems as if the boat is riding on air, until, suddenly, the crystal-clear waters reveal an expanse of luxuriant coral reef beneath us.