The Unique World of Dusk Snorkeling
Editorial by Joel Simon

My father was a fisherman. As a boy, I remember many evenings, after a day with rod and reel, spent cleaning fish in the laundry room sink. Hefty rock bass, lithe bonito and yellowtail, and sinuous tooth-studded barracuda. Although to some, the entrails of fish are worthy of strict avoidance, I found them fascinating, along with the scales, fins, and diverse overall design.

The eyeballs were my younger sister’s favorite part. She used to wait on the floor, looking up with the expectation of a puppy, until my father handed her the squishy round orbs. Then with the knowledge of a trained surgeon, although with somewhat different technique, she would extract the spherical translucent lenses. Delicately holding them between her tiny fingers, like shimmering pearls, she would place them in front of her own eyes, and go wandering around our home, flapping her elbows like fins and making very convincing gurgling sounds, followed by streams of giggles. My even younger brother, sister, and I, all took turns looking through the fish lenses, gurgling and swimming as a school of fish-eyed kids through the house. Although Dad was thoroughly amused, this behavior quickly convinced my mother, with looks of utter horror and disgust, to find sanctuary in more remote rooms.

We treated these fish eyes more as toys than tools, but it was my first contact with the inner workings of fish vision. As children, we assumed that the fish, when alive, shared the blurry, distorted view their lenses yielded to us. But later we learned that fish see underwater as clearly as we do on land. We also learned that vision was as important to a fish’s survival as it was to our own and that different fish see better at different times of day. Even in the laundry room sink, we could see that fish eyes came in different sizes. I particularly remember the giant bulging embolized eyes of rust red rock cod, brought up rapidly from the dark depths.

It is precisely this specialization of sight among fish that gives a unique excitement to snorkeling at different times of day, especially during the transitional hours of dusk. As we will learn, in greater detail in the following pages, twilight holds special challenges for the reef community, and affords observational opportunities for snorkelers that simply don’t exist at other times.

I discovered this more by accident than design. My buddy Dean and I had just arrived at Cinnamon Bay on the U.S. Virgin Island of St. John’s. Although late in the afternoon, this was our first visit to a tropical reef environment, and we couldn’t resist getting in the warm water. We grabbed our gear, jumped in, and started swimming. As for anyone first entering the realm of the coral kingdom, the scene was dazzling--the long tawny arms of elkhorn and staghorn coral reached upwards to greet us, along with schools of yellowtail snappers, blue tangs, meandering gold-flecked French angelfish, and we could see and hear the scrapes and crunches of rainbow parrotfish as they grazed. It was a world of activity and color.

But as the sun moved lower on the horizon, and eventually below, the colors began to fade, giving way to an eire dark grey blue world. Even the sounds had changed--gone were the crunchings of feeding parrotfish, the pops of shrimp, and the grunts of damselfishes. With the silence and dim illumination, came a change in our attitude. Our vision diminished, we became much more cautious, looking around with greater scrutiny, and sure that any minute, out of the hazy edge of our perception, something "major" would come along to place us inextricably in the middle of the food chain.

Nothing did, at least for us. But a small fish, that I’m sure was feeling the same trepidation, was not so lucky. Just below us, with speed beyond recognition, a grouper simply made the diminutive fish disappear. I looked into the large dark rolling eyes of the grouper, and couldn’t help visualizing my sister’s tiny fingers holding lenses from the eyes of similar fish in front of her own. In that moment, the innocence of our childhood antics suddenly disappeared, with speed equal to the unfortunate prey. Dean and I agreed it was probably time, or past time, to swim back to the beach.

I’ve never forgotten the sensations of spending my first tropical sunset in the water--the mystery, the intimidation, and the haunting episode of the disappearing fish. And although initially revealed through unplanned circumstance, the thrill of snorkeling at dusk has now become a highlight of any trip to the tropics.