What killed the Redondo Beach sardines? Nobody's sure. The only thing that's certain is that the 2.5 million dead fish smell terrible.
It's unclear whether human intervention somehow played a part, but the incident has parallels with fears in San Francisco over a potential deadly kelp proliferation that could be triggered by the America's Cup.
The cleanup effort at Redondo Beach is nearly finished, but it took some very heavy lifting and dedicated volunteers to get the 127 tons of dead sardines out of the marina, according to the CC Times.
We know that they suffocated to death. But we don't know know why they all crammed into a tiny little parcel of water, exhausting the supply of oxygen in the water. Were they fleeting a predator, disoriented, poisoned by chemicals? Nobody's sure.
Getting silvery decomposing bodies out of the water could wind up costing the city half a million dollars. Bodies were piled so high, boats couldn't get in or out.