EXUBERANCE OF LIFE greets photographer David Doubilet as he plumbs the remarkably fertile waters of the Strait of Georgia. An inland sea separating mainland Canada from Vancouver Island, the strait has long been a paradise for sport and commercial fishermen. Through the eye of Doubilet’s camera we now discover that a fantasia of strange and colorful sea life exists below the surface. In the shallows off one of the strait’s countless islands, an eel-like pinpoint gunnels (right) seeks shelter by threading its ten-inch body around the spines of a crimson sea urchin. PLAYGROUND and workplace for British Columbia’s peoplemost of whom live near its shoresthe Strait of Georgia is fringed with hundreds of fjords, bays, and estuaries (map). In summer a quarter of a million local pleasure craft fleck its surface, competing for space with fishing boats, log barges, and Alaska-bound ferries. But when winter casts its pall across the waters (above, looking west from Egmont), the province’s growing number of scuba divers enjoy the best season for their sport. During the warm months, a superabundance of plankton is whipped to a broth by tidal currentsas swift as 14 knots that flood and ebb through the strait twice a day. Visibility then may be limited to a foot or less. When winter storms arrive, however, and the great synthesizer, the sun, stays hidden behind cloud cover for much of its brief presence, the strait’s dense forests of kelp begin to die. By winter’s end the curtains of plankton have disappeared, and visibility may extend to a hundred feet in places. HUNGRY FINGERS plucking food from the cold nutrient-laden current, thousands of extended polyps impart a blurred image to a colony of soft corals (left). Overhead, in the north end of the strait, diver Wan-and Buck withstands the 50F (10C) temperature in one of the multi-layered outfits required in these waters. A three-inch scallop (above) eats as easily as it breathes by filtering plankton from the water it draws through its gills. Tiny beadlike eyes spangle the edges of a brightly colored mantle that folds out like lips from within the mollusk’s two valves. Covering them, like a second skin, is a layer of living sponge. Resembling larger eyes exhaust holes, seen here only on the bottom shell, allow the sponges themselves to breathe and feed.