Cusk Eels
© University of AberdeenFeeding frenzy! Cusk eels, photographed 3.7 miles below the surface of the sea, swarm some tasty treats.
Tens of thousands of dead eels have washed ashore in China over the past few weeks.

The eel is just the latest animal to die en masse in China's waters. In March, thousands of dead pigs were dumped by farmers into the Hangpu River in Shanghai, and hundreds of dead ducks and fish have also turned up in Chinese waterways.

Although no one knows the cause yet, some suspect the China National Offshore Oil Company may be responsible, the website Quartz reported. That company is doubling its crude oil production.

But the company and local administrators say the eels died of natural causes. The company says ocean currents brought a confluence of low temperatures, low oxygen and high salt content that killed off the eels, the South China Morning Post reported.