Sherrard Island offers us the rare opportunity to anchor our ship in the heart of Australia’s Great Barrier Reef. Surrounded by the dazzling variety of shades and hues given to the seas by the coral growth underneath, you can sit on deck mesmerized by the shifting light as the day progresses. Viewed with a snorkel and mask, the area reveals a kaleidoscope of 1,500 species of vividly colored fishes, tranquil coral and sponge gardens and occasional surprises that may include turtles or dolphins. The location, in the so-called Ribbon Reefs, is famous for its reliable clarity and profuse coral growth. Above the surface, the area is a major flyway for birds that can add many species to your life list. Name every shade of blue you can imagine. You’ll run out long before you catalogue the tints of sea and sky you’ll enjoy on your day in the Great Barrier Reef.