Humans have mapped only 25 percent of the seafloor, so the ocean is ripe for exploration and investigation. Environmental journalist and author Laura Trethewey recommends five books by 'ocean journalists' that explore the life, crime and science of the seas.

We plunder the ocean for food, dump our waste in it, respect its wildlife less than land-based creatures. Why? Is it a case of "out of sight, out of mind"? Marine biologist Helen Scales tells us what's down there and what we're doing to it.

Geologist Jan Zalasiewicz tells us about the danger posed to oceans by the Anthropocene – and how we can work together to protect them

Marine biologist Helen Scales reflects on the power of stories to bring all kinds of readers into the ocean realm. She recommends books for children and young adults, and explains why her selection focuses on novels for readers age 10-14.

The tidal zone is among the most vital and dynamic environments on Earth, but also one of the least well known. Here, the author Adam Nicolson explores formative works on the subject that have informed his book, The Sea Is Not Made of Water.

The travel writer casts his net over books about the sea and comes up with a haul including Moby Dick and a naval history of Britain.

The ‘subterranaut’ describes how the discovery of ancient bacteria miles beneath the Earth’s surface opens the possibility of finding life on Mars. He picks five books that show how our knowledge of life deep in this planet could lead us to discover it elsewhere.

The Australian environmental philosopher discusses man’s interaction with the oceans – from whaling voyages and dynamite fishing to sea gypsies and the flourishing business of piracy

People see in pirates what they want to see, says historian and author Adrian Tinniswood. He recommends five fascinating books about pirates.