The Deep The Hidden Wonders of Our Oceans and How We Can Protect Them

What does the deep ocean make you think of? An alien world right on our doorstep? The cradle of life? A global garbage dump? The lungs of the planet? Or the world’s most abused ecosystem? If I am to believe marine biologist Alex Rogers, the deep ocean is all of the above, and so much more. With three decades of research experience and scientific consultancy credits for the BBC series Blue Planet II under his belt, he knows what he is talking about and he knows how to talk about it. The Deep is an intensely captivating and urgent book that swings between wonder and horror.

I find the deep ocean one of the most fascinating ecosystems on our planet. Perhaps it is the final-frontier aspect, as so much of it remains unexplored (Rogers gives some mind-boggling statistics), or maybe it is the otherworldliness of its inhabitants, but I cannot get enough of reading more about it. Rogers’s fascination started at an early age, encouraged by summer holidays spent out on the ocean with his grandfather, an Irish fisherman. Although he recounts these formative experiences with great fondness, he also recognises the cruelty visited upon the unfortunate fish and lobsters that were caught.

A research career in marine biology followed and Rogers relates with great enthusiasm some of the highlights in marine science that he has lived through. Hydrothermal vents had only just been discovered in 1977 (see also The Ecology of Deep-Sea Hydrothermal Vents), and he participated in expeditions that first explored these deep-sea hot springs in the unruly waters of the Southern Ocean using remotely operated underwater vehicles. There was the ten-year Census of Marine Life (see also Discoveries of the Census of Marine Life). And, of course, technological developments allowed both manned and unmanned submersibles to venture deeper, capture better footage, and even carefully return samples to the surface (see also Discovering the Deep and In Oceans Deep).

This is the wonder in this book.

The furry yeti crabs, the dream-like towers of black smokers hiding in the abyss, the millennia-old corals, the predators that are all mouth and stomach. And do not get me started on the fish (see also my review of Deep-Sea Fishes). Rogers’s eyewitness descriptions of the bizarre fauna are mesmerizing. The colour plate section is only all too small.

Here is another strong suit of The Deep: Rogers shows the relevance of seemingly obscure scientific research. The confirmation that the deep-water coral species Lophelia pertusa – so different from tropical species – builds reefs might seem like academic arcana to outsiders. But it was decisive in a UK court judgement to recognise the continental margin of the UK (and by extension that of the European exclusive economic zone) as habitat in need of protection from oil exploration and other activities under the European Habitats Directive.

Rogers is that rare breed of scientist who is not content losing himself in his research. He has advised conservation NGOs, provided testimony in court, and worked on projects for the UN to name but a few achievements. He cares intensely and his fighting spirit shines through in his writing.

This is the horror in this book.

See, one of the biggest problems with the open ocean is its remoteness and its lawlessness (see also the forthcoming The Outlaw Ocean). Large parts of the oceans fall outside national jurisdictions and are effectively a marine wild west. Rogers effortlessly switches between the wonders of the denizens of the deep that we are only just beginning to discover, and the horrors of their destruction before we have even had the chance to properly take stock of what is out there.

The Deep is bang up-to-date on this front. There is the familiar spectre of overfishing: the rise of the industrial fishing complex, the harmful government subsidies, the collapse of fish populations, the destructive practice of trawling, the infuriating wastefulness of by-catches and simply catching more than the market can handle (see my reviews of All the Boats on the Ocean, Daniel Pauly’s Vanishing Fish, and The Curious Life of Krill, and references therein). But Rogers is equally at ease explaining the details behind ocean acidification, eutrophication with concomitant episodes of oxygen depletion and algal blooms (a topic I am intimately familiar with from my own studies), changing ocean temperatures and coral bleaching, and palaeoclimatological evidence of past changes (see also my review of The Oceans: A Deep History).

And then there is pollution. So much pollution. Untreated wastewater and sewage, discarded and lost fishing gear, oceanic garbage patches and microplastics (see Microplastic Pollutants and Microplastic Contamination in Aquatic Environments), persistent chemicals that accumulate in the food chain. Even something as topical as the chemical oxybenzone in sunscreen, recently banned in Hawai’i, is mentioned. And Rogers is warily eyeing up the imminent threat of deep-sea mining, as the world continues to hunger for rare earth elements (see also The Elements of Power, and the double-act Deep-Sea Mining and Environmental Considerations and Environmental Issues of Deep-Sea Mining).

Amidst this onslaught, Rogers continues to fight and eschews cynicism (though his success in court surprised even him). As opposed to terrestrial ecosystems, few marine species have yet gone extinct and fish populations can rebound if given the chance (see Ocean Recovery). He convincingly shows that marine protected areas are a vital tool to offer fauna and flora a safe haven (see e.g. Marine Protected Areas: A Multidisciplinary Approach and Marine Conservation), and joins E.O. Wilson in his call to set aside large tracts of the planet (see Half-Earth).

The Deep is an absorbing and passionately written book that successfully combines an eyewitness account of the biological bounty of the deep sea with first-hand reporting on the threats, the conservation initiatives, the (failure of) policies and treaties, the fierce industry lobbying, and the political shenanigans. The Deep is aimed at a general audience and Rogers has decided to leave out literature references, footnotes, and an index. But those omissions are a small price to pay. At a time when we need as many people as possible to take notice, and when a documentary such as Blue Planet II can shake a nation out of its stupor on plastic pollution, good storytelling is a necessary and promising approach.