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June 04, 1961 - Horseshoe CrabsHORSE SHOE CRABS (male on right) Exclusive Sunday Review Sketch by Dennis Puleston of Brookhaven Focus on Nature by Paul Stoutenburgh Cutchogue Come down to the bay with me just after the sun has slipped away and the wind has gone to rest. Here a quiet settles over our world where only a gentle working of the bay is heard. The atmosphere suggests to us that something is, about to happen. The stage. is set and sure enough, as soon as our eyes get accustomed to the darkness we see the ushers of the performance. They glide in, silhouetted against the dimly -lit sky. These are the Night Herons who have come to fish for the night, only to return to their roost before most of us are about. Later, when the darkness spreads its cloak, we know only of their presence by the familiar, unmusical "quok". But these are only part of the show, for the story I want to tell you is one that you should know if you are not familiar with our beaches at ebb tide in the spring. It is a story that starts over 200 million years ago, when this ivorld was just beginning, and the gtbtesque shapes of prehistoric beings were evolving. Our story is about the Horseshoe Crab or, as he is lanown to some, the king Crab. a4� Down the beach a short way our tale starts to unfold as it has each year at this time when they return from the deep to per- form their spring ritual. We see this creature s l o w l y lurching along, plowing half sub- merged as it lays its clusters of small green -tined eggs along the high tide limits. Attached to the tail of the large female 'is the smaller mate who travels alonp, to fertilize the eggs as they are laid. After a period of three to five weeks ,depending on the tempera- ture of the water and sand, the little crabs hatch out and start their never - ending b a t t l e for survival. D u r i n g the first year, the Horseshoe Crab s}ieds m a n y times. Most of us have seen soft shell crabs but few have ever observed the soft- shelled Horse- shoe Crab. And yet, often when we are out clamming in shallow water, we can trace these young crabs by following their tell -tale trails through the sand. What we find is a sand- colored leathery crab. This color changes as they grow older until they later become olive brown or red- dish brown in color. In shedding, the Horseshoe Crab differs from other crabs in that it sheds out the front of the shell rather than the back. Such a neat job of shedding is done that many times we see the discarded shells fully -intact along the shores. It is after shedding that t h e crabs grow and it is obvious that during this period they are most vulnerable to attack, for they stay in this soft condition for days until the sheit'hardens. Once it has acquired its hardened shell, this prehistoric tank can face the world unmolested. A full -grown female will reach the length of 20 inches, while males are much smaller in size. Many times I have found these old timers with the topside of the shell so covered with acorn bar- nacles and grass that it is hard to distinguish their two pair of eyes. One pair is directly in front while the other more obvious pair is located on the sides. Turn this grassy monster over and you will often see slipper limpets attached to the underside. 4 The jagged spear so character- istic of this crab is not used for defense or attack but rather to help right itself should it become overturned. Probably you h a v e seen this when a crab has been tossed up on the beach. The tail literally flips it over so that it may return to the sea. My interest in this little -known crab started one day when I was reading about the spider family and was amazed to see that the Horseshoe Crab belonged to this clan, and was not a crustacean as I had thought. His nearest relatives are the scorpions and spiders. Although it is not a true crustacean, it had the blue blood that characterizes mollusks and crabs. Actually, this crab is an air - breather, eve nthough it lives in the w a t e r. The manufacturing plant for this conversion is read- ily seen when one is turned over. This section, called the gill book, looks like a series of pages, one on top of the other. It is through these that oxygen is exchanged when these books are rhythmic- ally shaken as the crab hinges alone the bottom. Like m a n v of the common crabs, a Horseshoe Crab can live a long time out of the, water. In the olden days, farmers would go down with their wagons and col- lect the "horse feet ". These would be used for fertilizer or for feeding their pigs and chick- ens. Many times they were held over, alive, until needed. Today there is no s p e c i a l commercial value for them but occasionally. fishermen will col- lect them "for bait in eel traps. Theiy do no particular" harm ex- cept for the occasional scare they give a swimmer who has never faced one before. They feed on small inverte- brates and worms which they dig up in their constant plowing and burrowing. It is interesting to note that the crab must contin- ually be on the move in order to eat because he operates - similar to a machine that consumes as it runs. It is disheartening to walk along the beaches to see what length man will go to trying to eliminate these Horseshoe Crabs. To de- liberately destroy them, just be- cause they invade `bur" beaches in the springtime is ridiculous. Yet we who know Nature's way realize how insignificant this act' really is in comparison to the Multitudes of hardships and bat. tles this creature has overcome in the past 200 million years' FIELD OBSERVATIONS:_ Dennis. Puteston reports: Brook- haven — May 25 —Pay-breasted Warbler, Canada Warbler,'Mag nolia ' karbler, Chestnut -s i d id +n Warbler, Cape May , Warbler, Nashville Warbler; Parula ,Warb- ler. Black- throated Green rb- ler,- Gnatcatcher, Redstart, ve- backed thrush, Warbling reo, Northern Water Thrush. , Send your Field Observations or Comments to Paul Stoutenburgh, Route No 1, Box No 105, Bay Avenue, Cutchogue, New York. Next week we are having Keith McKenna, as our guest writer. He t e a c h es'Irnglish at Riverhead High and has a delightful way of explaining some of the things that many of Ls'teel.