"LA CORONILLA, Uruguay — 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.
“Kilometer after kilometer, as far as our eyes could see. All of them dead, rotten, opened up,” remembered Agüero, now 70. “They were all black, and had a fetid odor.”
He wept at the sight.
The clam die-off was an alarming marker of a new climate era, an early sign of this coastline's transformation. Scientists now suspect the event was linked to a gigantic blob of warm water extending from the Uruguayan coast far into the South Atlantic, a blob that has only gotten warmer in the years since."