The industry is strong, but the clam harvest is a far cry from what it used to be. The clam-digging record in 1923 was eight bushels per tide. In 2002, during the worst of a predatory green crab invasion, diggers were struggling to get half a bushel per tide. To meet demand, restaurants supplement the local supply with soft-shelled clams from around New England (most often Maine), the mid-Atlantic, and on rare occasions, even the West Coast.
Yet Ipswich clams continue to be the gold standard for regional chefs. This is, in part, simply a matter of place. As with any natural food, where the clam lives (and what it lives on) determines the nuances of its flavor. But mostly, when it comes to clams, freshness isn't an ideal of the farm-to-table movement, it's a definite science. The proteins of the clam begin to break down quickly, so storing them long is relatively disastrous. As Boston native Howard Johnson discovered when he tried to take the fried clam national, you simply can't freeze the Ipswich clam. Doing so destroys its water-heavy cell structure and turns the mouthfeel to mush. (This is why the chain used clam strips for its "tendersweet" clams; more on that in a minute.) Digging these clams, processing them, and serving them up all within the same few square miles provides the peak experience.