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December 13, 2001 - Honoring the horseshoe crabThe Suffolk Times * December 13, 2001 LAST WEEK I WAS PRIVILEGED to take part in a symposium at the City University of New York's Graduate Center. It was on a topic particularly dear to me, but seasonally out of plac for me to write about since I usually write about cur- rent happenings in the natural ON world. What the NATURE conference was about was "The by Paul Resilient Stoutenburgh Horseshoe Crab: Guardian of Time." It was about that lonely and misunderstood creature that many of you see in the springtime here in our local creeks and bays. The horseshoe crab, Limulus polyphemus, existed long before the dinosaurs roamed the earth 200 mil- lion years ago. It was around before the birds and mammals and plants made their appearance. The sympo- sium brought together scientists, ar- tists and other elements of society in the hope that through a better under- standing of the horseshoe crab and its ability to overcome the many obsta- cles of time, we might just correct some of the mistakes we've made in the past. We get a glimpse of this mysterious wanderer only in the spring, for that's the time of year the females come to the sandy beach edge with the males attached to their backs. The females lay their eggs in the sand along the high -tide line and the clinging male then fertilizes them. The females are larger than the males and often you'll see more than one male attached to the female, with some climbing over the others in hopes of being the one that will fertil- ize her eggs. The horseshoe crab's life cycle is fascinating. Once the eggs are deposited in the sand of the high, high -tide line, they are left to be developed by the warmth of the sun. Then approximately a month later, when there's a full moon and again that extra -high tide, the babies hatch from their egg cases and work their way out of the "sand and start their life cycle of molting, for like crabs, in order to grow they must leave their old shell behind. A horseshoe crab will molt 16 to 17 times before it reaches adult size, which is in about 10 years. Once it is WHonoriin horses o the FaM Photo by Barbara Stoutenburgh An empty shell of Limulus polyphemus, the resilient horseshoe crab. Just this past week it was the subject of a celebration called "The Resilient Horseshoe Crab: Guardian of Time," sponsored by the Americas Center on Science and Society at the City University of New York Graduate Center, coordinated by director Ron Hellman of GreenDort. an adult, it doesn't shed its shell any more. This is why you often see sea- weed, barnacles, slipper shells and other marine organisms attached to the body of the adult horseshoe crab, which, by the way, isn't really a crab at all but a member of the spider family. Where do they go? Horseshoe crabs plow along on the bottom of our bays eating worms, small crustaceans and mollusks of one sort or another throughout the year, only to return again in the spring to their ancestral spawning grounds. It is only then we get a glimpse of these remarkable living fossils. Shorebirds are depen- dent on this annual spawning of horseshoe crab eggs. Some shore- birds start their migra- tion north from as far away at Patagonia in South America. Many are totally dependent on horseshoe crab eggs to sustain them on their long, sometimes nonstop, flight to the Delaware Bay area, where literally thousands of these crabs come ashore to deposit their eggs. Here is the largest concentration in the world of Limulus polyphemus, the horse- shoe crab. With such a mass of churning crabs, there are many eggs that are not buried. It's these eggs that the gulls and shorebirds devour to build up their fat reserves for the next flight north to the Arctic tundra, where they will eventually nest. It's a remarkable sequence, with the, birds moving along from one concentration of horseshoe crabs to the next as the season progresses. Without these nutrient -laden eggs, we're not sure the shorebirds would survive. But there's more to horseshoe crabs than just their ability to lay eggs to help the shorebirds make it to their nesting grounds. Horseshoe crabs have many other uses. It's believed the early American Indians who lived along our shores ate the horseshoe crabs and used their long, rugged, sharp tails for the ends of fishing spears. Later, as European settlers moved into the picture, we find the horseshoe crab was used as bait for eel pots and conch pots. The ironic and sad part is that the female, loaded with eggs, makes the best bait. Then, not too long ago, factories along the Delaware Bay ground up millions of horseshoe crabs for fertilizer and poultry feed. Ask any old -timer on the East End about the number of horseshoe crabs they see today and I'm sure you'll get the same response I give: "There are far fewer horseshoe crabs now than when I was young." Could it be, like the canary in the coal mine that told the miners when the air became foul, that diminishing numbers of horse- shoe crabs are trying to tell us that we're not being particularly good stewards of our estuaries? Yet they have tremendous potential. As proof of this, The Nature Conservancy has listed Peconic Estuary as one of "Earth's Last Great Places" to be pre- served. The purpose of the conference was to discuss the many interesting aspects of the horseshoe crab and how we can help it continue to survive. After all, it has uses today that many are unaware of, such as those in medicine. Its blue blood is one of the best indicators of infection. So who knows, perhaps you or I have benefited from the horseshoe crab unknowingly in that it may have helped detect a medical problem. Its eyes, and it has many, were part of a 1967 No .e 'rite •issertation on the human eye. Much research is still going on using the horseshoe crab. Once the research is completed, the horseshoe crabs are released in the water with a more than 90% survival rate. Though I spent many years as a ranger natural- ist at the Fire Island National Seashore edu- cating groups of young and old alike through walks and lectures about the unique and interest- ing life of the horseshoe crab, my earliest experi- ence went back much further than that: My introduction almost 70 years ago was when as a kid I would go down to the channel with my dad in the spring when he went fishing for weakfish. That was the time when tarred line, heavy sinker and squid for bait were whirled around and let go. It would shoot out into the channel and there Dad would stand, holding the line, waiting for a bite. It was a time when 10- and 12 -pound weakfish were common, a time we have never seen since. It was then that I would see these mysterious creatures working their way to the water's edge, half buried in the sand. Little did I realize what wonders were going on beneath that massive dome. Then there was the old wives' tale that the pointed tail of the horseshoe crab was poisonous. It was my part at the conference to bring this historic background into view so that in sharing this with oth- ers, we can all realize that our resources have diminished by overuse, pollution, dredging and other opera- tions of mankind, and that only through science and education can these valuable resources be saved from further destruction. P.S. The exhibition of "Limulus: Visions of the Living Fossil," with culptures and reliefs by Brian Nissen, 's open until Dec. 20 from 10 a.m. to 7 .m. each day at the Americas Center n Science and Society, 365 Fifth Ave. t 34th Street.