Free-diver Andrews B. Heide captures what could be the first footage of a sperm whale diving off the coast of Norway in winter.

A dead sperm whale washed ashore in eastern Indonesia with 6 kilograms of plastic in its stomach. The rubbish included 115 drinking cups, 25 plastic bags, plastic bottles, two flip-flops, and more than 1,000 pieces of string. The whale’s exact cause of death is unknown, but observers say the whale may highlight the global plastic pollution problem.

Sperm whales are only at the surface for about 15 or 20 minutes at a time, yet photographer Brian Skerry is able to capture beautiful moments of these giant undersea predators. He experienced the rare opportunity to photograph a social gathering of six sperm whales near the eastern Caribbean island of Dominica. He witnessed fascinating behaviour such as whales playfully biting each other, rolling around, and babysitting. This assignment made Skerry realise that sperm whales are complex animals that have identity and personality, and exhibit traits similar to human beings.

Sperm whales are louder than any animal on Earth — a skill that might come in handy against Orcas.