PORTLAND, Maine (AP) — For New England's vanishing commercial clam harvesters, the coronavirus pandemic represents only the most recent in a string of setbacks that have held down the centuries-old industry.

The clamdiggers, who pull softshell clams for use in chowders and clambakes from tidal muck, have weathered an aging workforce, relentless predators that eat shellfish, warming waters and fickle markets. This summer's pandemic has held back few of the clamdiggers from plying their trade in the coastal clam flats that have fed their customers for generations, members of the industry said.

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