For a bounty of edible shellfish, you needn't venture out any father than the sand and rocks along the shore.
Our people need go no further than the shore and shallow water to begin harvesting the sea. Edible shellfish in great variety and number live in the sand and rocks of the first fathom. They are all excellent sources of protein, lean and delicious.
The quahog is called a cherrystone in its smallest sie (~2"), a little neck in medium sizes (~2"-4"), and a quahog in its largest sizes (~4"-6"). It is eaten raw or steamed in the case of the cherrystone or little neck, but the tough grandfather quahogs are reserved for stuffing and chowder.
The bay scallop is the sweetest morsel in the bivalve family. Because it is a rather special creature — a clam that gets around. Because it is fished with special methods and is a potential money crop, it is the subject of an article of its own.
The steamer, or softshell clam, is a seashore staple. Steamed, boiled, or as the star of its namesake, the clambake, it satisfies the body and soul of hunger. The maddening necessity of debearding — removing the black sheath from its long "neck" or siphon — makes it somehow more enticing, and more delicious.
Oysters in stew, broiled with spinach a la Rockefeller, steamed, or (for the initiated) raw, need little comment; they are the aristocracy of the order Mollusca.
The periwinkle is eaten, steamed, or baked in garlic butter, with justifiable gusto and unavoidable daintiness using a pin by the Portuguese here and by coastfolk of Europe, but Yankees avoid this amazingly plentiful snail of the rock and tide pool.
I cannot tell you why blue mussels are not as popular here as in Europe, only that whatever the reason, it is a foolish one. They are marvelous far, plentiful and easy to gather.
The tasty razor clam is a great digger and hard to find.
Oystermen: A clammer's work is a function of the tides; his quarry is accessible when the water level is lowest. The oysterman searches hard shelf bottoms and rocks submerged at mid-tide for the white, irregular shells that cling to the surface and pries them loose. The size limit to shellfish is not arbitrarily fixed, but calculated to give each clam time to reproduce its replacements — the limit is designed to perpetuate the cycle.
Musselhunters: Mussel beds are dark and thick in many-edged clusters. The blue, smooth,clams (ribbed marsh mussels, the striated variety, are really terrible) are pulled from the pebbles and rocks and pilings, to which they cling by the byssus, the mass of strong filaments that must be removed by scrubbing (a stainless steel pot scrapper is the easiest) before steaming in a small amount of wine and water.
Clammers: There are places in your back you do not know about, yet, that you will discover when you go clamming. The posture required for turning up the 6"-12" of silty sand (gently, for the tines of the clam hoe can slip right through the soft shell) will help you find those places. Hunt for breathing holes in the surface of the sand, and soad the steamers for an hour or so in seawater to allow them to "spit out" their gritty sand. Store all clams cool and dry; they will perish quickly in oxygen depleted water.
Quahog Digging: One method of quahoging is to rake up soft bottom with a quahog rake, sifting sand and silt through the basket to leave your catch. Barefoot, you can skooch your toes through the sand, even among the rocks, hunting for the reclusive devils. If your basket isn't buoyed up, attach a float to the handle or you will lose it in the muddy water.
Individual shellfish rights of towns and villages along the coast have been jealously maintained since colonial times, to the first requisite for a body to go a clammin' is a permit. They're available at town hall. Some towns issue permits to residents only, some will provide temporary licenses to summerfolk. Permits for family consumption are inexpensive and easy to obtain, while commercial permits are more expensive and many be limited to a fixed number within a township. In some places clamming may be restricted to certain beaches and tidelands, which will be indicated on a map at venerable town hall. The shellfish warden is a good man to know, for information and advice. As in most sea pursuits, the old men know where, when, and how, even though clam hauls of the horsedrawn days sound superhuman.