Picture a fleet of floating Christmas trees, merrily bobbing and splashing in a waterborne conga line, each one a testament to the combined do-it-yourself spirits of tree decoration and maritime life.It’s not a dream, though it may look like one.The 62nd Christmas Ships Parade, a 15-night festival of Santa Claus on the river, gets underway the night of Dec. 2 and wraps up Dec. 18. Every evening (except Sunday the 4th and Monday the 12th), local skippers who are more or less submerged in holiday cheer show off the vessels they’ve decorated with dancing lights, seasonal characters and other eye-grabbers that really stand out after the sun goes down.Santa driving a team of reindeer is just the start of what you’ll see on the water. Nutcrackers and snowmen, candy canes and glowing wreaths, graceful swans and smiling whales, joyous elves and the wicked old Grinch himself are all part of this wishy-washy convoy. Organizers expect as many as 60 different crafts to take part this year. It’s a great example of riverborne, just-for-fun, labor-of-love volunteerism; some skippers spend hundreds of dollars and countless hours developing plans and decorating their boats — all so they look just so from the banks of the river.“Wires, wires, wires. I’ve been running lots and lots of wires,” was what Vancouver Christmas shipper Larry Aberg said as a Columbian reporter climbed aboard his boat, the Bubinga, last year. Aberg, an electrical engineer, has also taught some “decorating for Christmas shippers” classes during organizational meetings of this group, and he’s been glad to share how technology has improved in recent years.Once upon a time, a skipper might dip light bulbs in red and green paint, one by one, and try to improvise some way of keeping the whole assembly dry while bouncing and splashing on the water; nowadays, you can buy dazzling, plastic-encased rope lights that are programmable to create whatever sorts of illusions you’re looking for — like galloping reindeer legs and spinning fire engine wheels.