Page:American Seashells (1954).djvu/75

Rh It is most surprising how many treasures within arm’s reach are lost to the uninitiated. A waterlogged board if kicked aside may be found to contain three or four kinds of interesting wood-boring clams; a rock unturned at the end of the beach may still shelter a pair of cowries or a nest of orange-tentacled Lima Clams; or the seafan momentarily admired and cast aside may be the holdfast for a colony of rare, purple Simnia snails. All mollusks have their particular ecological niches or favorite haunts, whether a very limited type of locality or more extensive areas such as mud flats, rocky shores or the open ocean. To be forearmed with a knowledge of where our species live will often bring rich rewards from salt marshes, eel-grass flats, mangrove trees, the backs of other marine creatures, the underside of boats or even the stomachs of fish. The tracks made by gastropods on sand or mud bottoms are characteristic for many species and can aid in hunting down live specimens. So, too, holes of certain shapes and sizes in the sand flat are a betrayal of the clam occupant deep below. At times it is worthwhile to know when and where gregarious mollusks gather to breed. Their appearance is often clocked not only by the seasons but often by tidal conditions and the time of day. Most intertidal species reveal themselves more frequently about half an hour after the tide has begun to rise. A great number of species are more active a few hours after dark, while others are content to wait until early morning before starting on their foraging missions.

Attention to tides, seasonal moods of the ocean and the effects of winds and currents is put to good use by the expert collectors. September seems to be the most favorable time, for instance, to gather shells on the Carolina strands. During late April and early May there is more likelihood of the Purple Sea Snail, Jathina, being washed ashore on the east coast of Florida. After winter gales, some New England beaches may be strewn with millions of large Surf Clams, Spisula.

Low tide is obviously the best time to collect, and most collectors make long-range plans to catch the spring tides. Local newspapers publish the times of low and high tides, but many serious collectors prefer to use the Coast and Geodetic Survey Tide Tables to plan well in advance for the lowest tide of the month. Tide Tables for the Pacific and Atlantic coasts may be obtained for a fraction of a dollar from the U.S. Department of Commerce, Washington 25, D.C.

As you may well know, the rise and fall of tides are caused by the attraction of the moon, and to a lesser extent by the sun. Choose the time of the new and full moon for collecting, for that is when the sun and moon are uniting their forces to give the lowest or spring tides. Low tide lasts for about fifteen minutes, but profitable collecting may be done one hour before or after. It is sometimes useful to know that the tides are about fifty minutes later the following day. Be aware of the dangers of rising tides,