This is Kennedy Warne’s memoir of a life lived in response to the “sea’s deep beckoning”. He takes us on journeys and dives spanning more than two decades, including on National Geographic assignments to South Africa, the Okavango Delta in Botswana, Arabia, Kiribati and Tuvalu, and the Philippines, as well as for New Zealand Geographic, of which Warne is the founding editor. The writing is lyrical, the encounters over a lifetime rich with beauty, diversity, and wonder: kelp forests, a pod of a thousand dolphins, sperm whales in the bioluminescent depths stroking one another with their flippers, ancient marine turtles, a seahorse curling its tail around Warne’s finger. Many of the descriptions are breathtaking, transporting readers to underwater realms most of us will only ever enter via flatscreens.

Some of these realms no longer exist. The power of this book is that it shows us the speed of sea change as measured within the short span of a human life. It is akin to watching an elderly David Attenborough revisit earlier footage of himself in places rendered unrecognisable.

The weekend Warne arrives in Greenland, the ice sheet there sets a record, shedding so much meltwater in just two days it could have raised the level of Lake Taupō by 30 metres. In the region of the Indo-Pacific known as the Coral Triangle, he swims through a silent “sepulchral world of stressed, diseased and dying corals, from which other creatures have largely disappeared”. He is keenly attentive to complex ecological interconnections, including those of humans with the sea. Some of the most moving moments describe the lives of those most directly dependent on the ocean, like a gleaner seen scavenging a devastated reef in the Philippines, towing a battered polystyrene box for his meagre catch.

The book is not without glimpses of hope. On his writing desk, Warne keeps the eardrum of a sperm whale to remind him to listen to what the ocean has to say. He probes the ethics of ‘encounter’, including curated tourist moments, asking if these might at times enable a “relationship reset”. Marine ‘no-take’ reserves are one of the developments in which Warne sees most potential. There is the question, though, of what local efforts can achieve in the face of planetary change: it is projected that by 2050, more than 90 per cent of the reefs in the Coral Triangle will be critically threatened by climate impacts. When Warne puts this question to a coral reef biologist, the scientist answers that solutions like marine reserves “delay the inevitable”. They buy time, re-creating ecosystems with more stability to withstand environmental shocks. Marine reserves are “an insurance policy”, Warne writes, taken out “as earth systems fail”. It is a sobering description. His wider question throughout: How can we care for and reconnect with the oceans around us?

It is fitting that Warne’s story is framed by his own deep, familial and formative connection to a particular ocean place. Soundings begins with Warne’s boatbuilder grandfather and tall tales of big-game fishing, and it ends with the ecological recovery around Deep Water Cove in Maunganui Bay, restored by a rāhui placed on it by the local hāpu (see ‘Angler’s El Dorado’, Issue 103).

Warne suggests we need to become—or return to being—what Papua-born philosopher Epeli Hauofa called “custodians of the ocean”. We need to foster and find specific intimacies, like the kinship-custodianship bonds of kaitiakitanga. His beautiful book of soundings of the deep is an immersive act of storytelling, and an urgent call to listen.