In 2005, fishermen pulled out 316 tons of tilapia, a tasty freshwater fish, from the Sea of Galilee in Israel. But four years later, the catch had fallen to just 8 tons. This wasn’t just another story about overfishing, though: Throughout the country, in the summer of 2009, farmed tilapia were also dying en masse.
“Farmers lost 20 to 30 percent of the fish in their ponds, and it was spreading from one pond to the next,” recalls Avi Eldar, a state-employed fish vet, who was called to investigate. The enigmatic die-offs didn’t fit any known parasite, toxin, bacterium, or virus. “We couldn’t diagnose the problem. We suspected that there was a new bug in town.”
Whatever the new infection was, it was only killing tilapia, without harming other fish. That’s a small consolation, though. Tilapia are thought to be the fish that fed multitudes in the New Testament, and they play the same role in the 21st century. Being large, tasty, quick to grow, and phenomenally easy to farm, they’re the core of a 7.5 billion dollar aquaculture industry that provides a critical source of protein for the developing world. Even America, the world’s leading tilapia importer, consumes 225,000 tons of the world’s 4.5 million ton stock.
The point is: “dying en masse” aren’t words you want to hear in relation to tilapia.
