About two dozen of them sat in small boats, keeping quiet as they waited for the pirarucu to show themselves.To avoid injury while landing it, the fishermen resorted to what seemed like Flintstones technology: They used wooden clubs to knock the fish senseless, then pulled it into the boat.Starting in the 1960s, bigger boats and motors, improved nets, plus ice-making machines allowed fishermen to catch more pirarucu and preserve them for days until they could get down river to Amazonian towns and cities, where most of the fish are sold.Another problem, according to Torres, is that President Jair Bolsonaro, who lost his bid for reelection in October, has spent the past four years rolling back environmental laws and promoting a free-for-all of fishing, logging and mining in the Amazon.Torres, who had met with Pereira last year to discuss illegal fishing, says the killings shocked Brazilian environmentalists."