I'm standing on dry(ish) ground: sand that is just damp. Suddenly, we're up to our knees in water, and the cold splash comes all the way up to our shoulders. We jump a bit. The roar of the breaker is quickly replaced by the carbonated hiss of the receding waters, full of popping bubbles.
Shelling on Sanibel isn't like other places. Huge iridescent dark shells as big as my outstretched hand litter the shore at the high tide mark, so common that one little boy has built his sandcastle mostly out of the ones nearby. We dicuss what they might, inconclusively, along with wondering about the papery tubes littered all over. Big clam shells are so common that you could outfit the Carolingian Cooks Guild with flour scoops just from the ones found along a few feet of shoreline.
Birds abound, looking for their meal among the bivalves. A posse of little terns huddle and strategize just above the tide line. As the wave washes out, they walk along with it; as the next one splashes in, they run back up to the safety of the seaweed. A pelican floats lazily, a couple dozen feet out, unperturbed by the way he is rising and falling four feet every few seconds.
One realizes that Sanibel is shells, an eight-mile-long sandbar of them, and nothing more. Every few dozen yards, we encounter a stretch of shore that is made of nothing but small shells -- I can reach down, scoop up a handful, and come away with half a dozen small but elegant perfect shells that would be a prize on most beaches, but which aren't even worth the dime a dozen here. A bit further on and it is entirely made of fragments and shards a millimeter in size, not really shells any more but not quite willing yet to surrender to sandy senescence...