The day the yellow clams turned black is seared in Ramón Agüero’s memory. It was the summer of 1994. A few days earlier, he had collected a generous haul, 20 buckets of the thin-shelled, cold-water clams, which burrow a foot deep into the sand along a 13-mile stretch of beach near Barra del Chuy, just south of the Brazilian border. Agüero had been digging up these clams since childhood, a livelihood passed on for generations along these shores. But on this day, Agüero returned to find a disastrous sight: the beach covered in dead clams. An empty yellow clamshell rests on the beach in Barra del Chuy, Uruguay. Clam harvests have plunged 95 percent from the peak of 220 tons in 1985 as ocean temperatures have warmed. “Kilometer after kilometer, as far as our eyes could see. All of them dead, rotten, opened up,” remembered […]