Monday, May 14, 2018

Sound unseen

It was near midnight on a late May evening a few years ago that I walked along the mile-long sandspit of Napatree Point in Westerly, one of a handful of volunteer citizen scientists counting breeding horseshoe crabs. During a break in the action, I stared toward the crashing waves and saw what appeared to be a brief blue-green flash of light. And then another. In that moment, it reminded me of a distant flash of lightning or the green flash some say is visible at the instant the sun sets. It wasn’t until later that I realized it was a mass of tiny marine organisms that have the remarkable ability to illuminate themselves when they are disturbed, a phenomenon called bioluminescence.
I had read about it and heard that there were places in Puerto Rico and Malta and Japan where bioluminescence could be observed regularly. But here in Little Narragansett Bay, at the
eastern edge of Long Island Sound? Not likely. I convinced myself that I was mistaken, until I called Cris Sodergren at Mystic Aquarium, who has spent much of his life traversing the Sound day and night in all kinds of vessels.
Cris reminded me that most people only stare at the waves in the daytime, and they completely overlook what happens in the marine environment at night. He said the Sound is alive after dark, and during certain times of the year, it emits a radiant glow that can be mesmerizing, like our own version of the northern lights. He described several species of jellyfish-like creatures called comb jellies about the size of a golf ball that can look like shimmering green orbs, as well as single-celled dinoflagellates and a couple varieties of algae that also put on a light show when the crashing waves irritate them.
“Sometimes when I go fishing at night, with every paddle stroke of my kayak, the water sparkles,” he said.
I wouldn’t have believed it had I not seen it with my own eyes. But then again, there are plenty of other creatures in the Sound that generate a similar sense of wonder and make me feel lucky I live nearby.
For instance, grab a dive mask and swim in any shallow cove less than 10 feet deep where the long blades of eelgrass grow. If you look close enough, you may spot another unexpected native creature, a lined seahorse. These adorable animals – technically they’re a type of fish – use their prehensile tails to hold onto the eelgrass while waiting for microscopic plankton to swim by, which they eat by inhaling them through their snout. They’re cryptically colored in earth tones, so they’re easy to miss, but at 5 to 6 inches from tail to crown, you should be able to spot one with a little patience.
While you’re there, watch for other small creatures in the vicinity. The habitat serves as a nursery ground for fish, so tiny versions of flounder, tautog, bluefish, striped bass and other species will be hiding among the grasses. You might even come across a spiny pufferfish, which are becoming increasingly common as the waters of the Sound become warmer.
Eelgrass beds are also the best place to find bay scallops, which sit on the sediments filtering tiny organisms and watching for predators using their three-dozen bright blue eyes. When the shadow of a predator approaches, they clap their shells together to lift themselves off the seafloor and escape into the murky distance. This unusual skill makes them the only mollusk that doesn’t bury itself in the sediment or attach itself to a rock.
If those modest creatures don’t get you excited, then imagine traveling to the deepest depths of the Sound, more than 200 feet down, where you might come across an Atlantic wolffish hiding in the nooks and crannies of a rockpile. Five feet long and 40 pounds, with an eel-like body and a mouth full of frightening teeth, they have the reputation for biting through broom handles – though why anyone would give a fish a broom handle, I don’t know – and fighting their way into and out of lobster traps. Sharing the depths with the wolffish are several kinds of sharks, including sand tiger and sandbar sharks, as well as skates, squid, stripers, hake and many other species, even an occasional tuna.
Back at the surface, I’m always pleased when I catch sight of one of the handful of marine mammals that make their home in the Sound during parts of the year. Harbor seals are easiest to find in winter, but harbor porpoises – the smallest marine mammal in the North Atlantic – get my heart racing whenever I see their pint-sized dorsal fin pierce the water line. And although I haven’t spotted one yet, I know several varieties of sea turtles ply our waters in late summer and are regularly spotted taking a breath at the surface.
There are many more amazing marine creatures to seek and observe in the Sound, from crabs and starfish in tidepools to anadromous fish like sturgeon, herring and eels on their way back to our local rivers to spawn. And while the warming waters are becoming less attractive to cold water species, southern species are filling in the gaps, like kingfish, Spanish mackerel, red drum and bonito.
Whether you observe them at the end of a fishing line, with a snorkel in your mouth, or from your favorite lookout, get out there and pay attention. The Sound is a wonderful treasure trove of marine life to behold.

This article first appeared in Coast and Country on May 7, 2018.

No comments:

Post a Comment