GRIMY AND GRIM: Post-mortems revealed plastic as the cause of death for 13 sperm whales that beached on the German coast in January. Mistaking fishing nets and car parts for food, the animals filled their bellies with the debris and starved to death.

SHRINKING ON THE RISE: On Thursday, federal scientists found that the Arctic Ocean’s winter sea ice cover is at a 37-year low.

CAT AND MOUSE: A lion named Sylvester escaped from a South African national park for the second time. During his last romp, the lion killed 30 animals in three weeks.

ASH IN ALASKA: One of Alaska’s most active volcanoes erupted, covering 400 miles of the state in ash.

GLOBAL ENERGY NETWORK: China unveiled its proposal for a global clean energy network that would link solar farms, wind turbines, and electricity plants across Asia, Europe, Africa, and the Americas.