California officials are trying to solve a stinky mystery: A die-off has left hundreds of fish floating in a recently restored lagoon on the tony Malibu coast. Scientists believe the Malibu Lagoon die-off, which began last week, is likely caused by unusually warm water temperatures, said Craig Sap, superintendent of California State Parks’ Angeles District. “We had many days in a row of warmer-than-usual temperatures. We hadn’t had much of a breeze down there to keep the temperatures down,” Sap said Monday.