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Profile Books The High Seas Ambition, Power and Greed on the Unclaimed Ocean.
'A vital, fascinating, deeply researched exploration of Earth's last wilderness... Shocking and starkly illuminating - a must-read.' Gaia VinceThe ocean covers seventy per cent of the surface of our planet, and two thirds of this lie beyond national borders. Owned by all nations and no nation simultaneously, these waters are home to some of the richest and most biodiverse environments on the planet. But they are also home to exploitation on a scale that few of us can imagine. Here, industry and economic progress rule and lax enforcement and apathy are the status quo. Out of sight and often out of mind, a battle rages to control, profit from, protect, or obliterate the world's largest, wildest commons. Heffernan sets sail on a journey to uncover the truth behind deeply exploitative fishing practices, investigate the potentially devastating impact of deep-sea mining, and hold to task the Silicon-valley interventionists whose solutions to climate change are often wildly optimistic, radically irresponsible or both. The result is a forceful and deeply researched manifesto calling for the protection and preservation of this final frontier - the last vestiges of wilderness on Earth.
352 pages, Paperback
Published July 3, 2025
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Displaying 1 - 12 of 12 reviews
June 10, 2024
"Our vast, deep ocean is incredibly fragile and its greatest threat is us."
Heffernan writes at the end of this insightful volume that she had intended to write a book laced with hope, given the recent moves towards a Treaty of the high seas, but through her process of research, she instead slipped further into despair. This book is focused on current events - light on explanatory science, instead Heffernan aims to catch us up with momentus events around the oceans that comprise most of our planet's surface.
It is to her credit that this book is not a depressing read, but it is one in which terror starts to slip in the gaps between the reporting, as Heffernan covers a variety of topics with a depressingly homogenous set of drivers towards ecological failure.
The High Seas of the title refers to the pelagic ocean beyond national ownership, the "wild west" of pirates in lore. As we head towards an unprecedented globally interlinked ecological crisis, the role of global commons becomes crucial. With no longer a need for a place beyond the law, the question becomes how do we govern.
Chapters here include foci on fishing rights, illegal fishing, shipping, gene piracy, deep sea mining, waste disposal (including space junk) antarctic ice melt and iceberg towing. There are absolutely bright spots, especially the results of crusaders against illegal cartels and the use of both diplomacy and technology to curb them. There are some mixed stories, Heffernan covers the complexity of genetic sampling briefly but intelligently, highlighting the costs of global inequity and unequal power balances. But most of this is a not only a tale of woe, but depressingly similar. The cumulative damage to the ocean from these combined activities is pushing to tipping points, but each individual contribution tends to point to the others as being worse, or cites their own relatively small impact vs the vast ocean. As science and technology advance in unprecedented leaps, the ocean promises solutions to existing anthropocene problems, and the pesky fact that taking such risks is how we got here in the first place seems a little guache to mention. Mining companies, fishing companies, transport companies, cruise lines, NASA all hold enormous power within national governments which protect them. There is an absurd number of ways protective zones can be established, yet few are adopted, and when they are, they rarely make any difference. (One particularly headspinning paragraph explains we now have more than 270 designated Ecologically or Biologically Significant Marine Areas (EBSAs). Within these, there are also designated VMAs or Vulnerable Marine Systems, as well as IBAs (Important Bird Areas) and IMAs (Important Marine Mammal Areas). Yet, while Pelagos has aspects of all of these, it is so badly protected by them - industry still operates freely - that the WWF is applying for a new kind of status, a Particularly Sensitive Sea Area (PSSA) in order to strengthen it).
The other shocking component that Heffernan finds is how much of the destruction is to benefit a tiny percentage of the world's population. Sea bed trawling, pelagic fishing, all basically work largely for luxury fish which are far from staple foods. The majority of plastic waste in the oceean actually comes from industrial fishing - and including land plastic, just 20 companies account for 55% of global plastic waste. While medicines from genetic patents have underpinned enormous worldwide enhancements, the profits being fought over are concentrated in a tiny number of hands.
And perhaps most devastatingly, there is ongoing appetite for quick, high risk, solutions: "The suggestion of towing icebergs across oceans to solve the world’s water shortages may be a folly of sorts, but it’s symptomatic of our relationship with the planet. As challenging as such a scheme sounds, to us it seems somehow easier than looking for durable solutions to our environmental problems, such as reducing water use in parts of the world, curtailing our greenhouse gas emissions, or consuming our ocean resources more mindfully. At a societal level, this inertia means we consistently choose the present over the future, taking ecological decline as the inevitable hit."
Heffernan is not ultimately calling on us to change habits, although she notes it can't hurt. But the reality she tracks is that it is policy descisions and the acts of the wealthy and the incorporated which are driving the damage, not consumers or hungry and thirsty populations. Change must come through visibility and demands for it, not choosing your diet more carefully.
This is an important read, and a nice companion to James Bradley's Deep Water, which takes a more economic and science tack. It feels like an urgent book. It will date quickly, and hopefully Heffernan will prove overly pessimistic. But one thing that might help is more people reading and digesting this material (as opposed to illegally and/or irresponsibly caught fish).
Heffernan writes at the end of this insightful volume that she had intended to write a book laced with hope, given the recent moves towards a Treaty of the high seas, but through her process of research, she instead slipped further into despair. This book is focused on current events - light on explanatory science, instead Heffernan aims to catch us up with momentus events around the oceans that comprise most of our planet's surface.
It is to her credit that this book is not a depressing read, but it is one in which terror starts to slip in the gaps between the reporting, as Heffernan covers a variety of topics with a depressingly homogenous set of drivers towards ecological failure.
The High Seas of the title refers to the pelagic ocean beyond national ownership, the "wild west" of pirates in lore. As we head towards an unprecedented globally interlinked ecological crisis, the role of global commons becomes crucial. With no longer a need for a place beyond the law, the question becomes how do we govern.
Chapters here include foci on fishing rights, illegal fishing, shipping, gene piracy, deep sea mining, waste disposal (including space junk) antarctic ice melt and iceberg towing. There are absolutely bright spots, especially the results of crusaders against illegal cartels and the use of both diplomacy and technology to curb them. There are some mixed stories, Heffernan covers the complexity of genetic sampling briefly but intelligently, highlighting the costs of global inequity and unequal power balances. But most of this is a not only a tale of woe, but depressingly similar. The cumulative damage to the ocean from these combined activities is pushing to tipping points, but each individual contribution tends to point to the others as being worse, or cites their own relatively small impact vs the vast ocean. As science and technology advance in unprecedented leaps, the ocean promises solutions to existing anthropocene problems, and the pesky fact that taking such risks is how we got here in the first place seems a little guache to mention. Mining companies, fishing companies, transport companies, cruise lines, NASA all hold enormous power within national governments which protect them. There is an absurd number of ways protective zones can be established, yet few are adopted, and when they are, they rarely make any difference. (One particularly headspinning paragraph explains we now have more than 270 designated Ecologically or Biologically Significant Marine Areas (EBSAs). Within these, there are also designated VMAs or Vulnerable Marine Systems, as well as IBAs (Important Bird Areas) and IMAs (Important Marine Mammal Areas). Yet, while Pelagos has aspects of all of these, it is so badly protected by them - industry still operates freely - that the WWF is applying for a new kind of status, a Particularly Sensitive Sea Area (PSSA) in order to strengthen it).
The other shocking component that Heffernan finds is how much of the destruction is to benefit a tiny percentage of the world's population. Sea bed trawling, pelagic fishing, all basically work largely for luxury fish which are far from staple foods. The majority of plastic waste in the oceean actually comes from industrial fishing - and including land plastic, just 20 companies account for 55% of global plastic waste. While medicines from genetic patents have underpinned enormous worldwide enhancements, the profits being fought over are concentrated in a tiny number of hands.
And perhaps most devastatingly, there is ongoing appetite for quick, high risk, solutions: "The suggestion of towing icebergs across oceans to solve the world’s water shortages may be a folly of sorts, but it’s symptomatic of our relationship with the planet. As challenging as such a scheme sounds, to us it seems somehow easier than looking for durable solutions to our environmental problems, such as reducing water use in parts of the world, curtailing our greenhouse gas emissions, or consuming our ocean resources more mindfully. At a societal level, this inertia means we consistently choose the present over the future, taking ecological decline as the inevitable hit."
Heffernan is not ultimately calling on us to change habits, although she notes it can't hurt. But the reality she tracks is that it is policy descisions and the acts of the wealthy and the incorporated which are driving the damage, not consumers or hungry and thirsty populations. Change must come through visibility and demands for it, not choosing your diet more carefully.
This is an important read, and a nice companion to James Bradley's Deep Water, which takes a more economic and science tack. It feels like an urgent book. It will date quickly, and hopefully Heffernan will prove overly pessimistic. But one thing that might help is more people reading and digesting this material (as opposed to illegally and/or irresponsibly caught fish).
June 8, 2025
An interesting deep dive into the historical legal frameworks that have been applied to the High Seas. Issues covered include industrial fishing and overfishing, pirate fishing, marine carbon dioxide removal projects, microbes and discoveries of new antibiotics and cancer-killing drugs, dumping of plastic and rockets, deep sea mining, Arctic shipping, and harvesting of freshwater from icebergs. Each topic was discussed within historical, modern-day and scientific context. Modern-day players and experts in each field are introduced, putting a face onto sometimes esoteric and often depressing topics.
As an oceanographer, I was familiar with or at least had heard of most of the topics. (I hadn’t heard that Saudi Arabia wanted to bring icebergs across the equator to provide a source of fresh water for their population. ! Pretty funny imagining that!) But putting it all together, with context, statistics, and perspective from scientific experts really was an eye opener.
We are living the Wild West.
Heffernan talks about the services provided by the oceans — absorbing heat and carbon dioxide, producing oxygen. What was missing was the memory the ocean provides for weather and climate. Nations around the world, but until now primarily the US, have invested infrastructure in the high seas for providing observations that allow marine forecasts over the High Seas, weather forecasts over land at 10-days and subseasonal-to-seasonal climate forecasts around the world. Will next winter be dry? Warm? Have a good snow pack? Will the tropical depression spin up to a hurricane? Will the moisture converge into an atmospheric river? Will the Jet Stream get wobbly?
Within minutes of being made, measurements from the Global Ocean Observing System are telemetered to operational modeling and data centers around the world and then are made publicly available to any researcher with internet. This is a happy story of nations working together for the common good. It is a story worth highlighting not only to offset the depressing stories of greed and short sighted actions, but also because it is so very fragile.
Heffernan’s powerful voice could help put more eyes and ears on the High Seas that could help tap into its memory and help provide important information about the future.
As an oceanographer, I was familiar with or at least had heard of most of the topics. (I hadn’t heard that Saudi Arabia wanted to bring icebergs across the equator to provide a source of fresh water for their population. ! Pretty funny imagining that!) But putting it all together, with context, statistics, and perspective from scientific experts really was an eye opener.
We are living the Wild West.
Heffernan talks about the services provided by the oceans — absorbing heat and carbon dioxide, producing oxygen. What was missing was the memory the ocean provides for weather and climate. Nations around the world, but until now primarily the US, have invested infrastructure in the high seas for providing observations that allow marine forecasts over the High Seas, weather forecasts over land at 10-days and subseasonal-to-seasonal climate forecasts around the world. Will next winter be dry? Warm? Have a good snow pack? Will the tropical depression spin up to a hurricane? Will the moisture converge into an atmospheric river? Will the Jet Stream get wobbly?
Within minutes of being made, measurements from the Global Ocean Observing System are telemetered to operational modeling and data centers around the world and then are made publicly available to any researcher with internet. This is a happy story of nations working together for the common good. It is a story worth highlighting not only to offset the depressing stories of greed and short sighted actions, but also because it is so very fragile.
Heffernan’s powerful voice could help put more eyes and ears on the High Seas that could help tap into its memory and help provide important information about the future.
This entire review has been hidden because of spoilers.
February 26, 2025
Great book club read! Excellent writing that weaves narrative and scientific information together in a compelling and engaging way. I learned so much about the ocean and the interconnectedness of our plant.
June 30, 2024
Clear and well-written account of what is going on over the far horizon, and why it matters to all of us.
June 11, 2024
I received a free copy of this title from Greystone Books. Thank you Greystone and the author!
“The High Seas” by Olive Heffernan is a wonderfully informative dive into the complexities of the high seas and conservation for this incredible part of the planet.
The book expertly delves into issues such as mesopelagic fisheries, deep sea mining, climate intervention efforts, pollution, and climate change. The author does a fantastic job connecting each issue together, highlighting the circumstances of the threats, and related policies to better understand the issues of management of the high seas.
“The High Seas” ends with a resounding call to action, urging readers to advocate for meaningful ocean protection measures through systemic change. Voting is a huge aspect of environmental protection measures.
If you are interested in marine biology, fisheries, environmental science, climate change, or environmental policy, I highly recommend you pick this up! And even if you aren’t interested in those specific topics but want dive into the complex world of conservation, give this book a read!
“The High Seas” by Olive Heffernan is a wonderfully informative dive into the complexities of the high seas and conservation for this incredible part of the planet.
The book expertly delves into issues such as mesopelagic fisheries, deep sea mining, climate intervention efforts, pollution, and climate change. The author does a fantastic job connecting each issue together, highlighting the circumstances of the threats, and related policies to better understand the issues of management of the high seas.
“The High Seas” ends with a resounding call to action, urging readers to advocate for meaningful ocean protection measures through systemic change. Voting is a huge aspect of environmental protection measures.
If you are interested in marine biology, fisheries, environmental science, climate change, or environmental policy, I highly recommend you pick this up! And even if you aren’t interested in those specific topics but want dive into the complex world of conservation, give this book a read!
December 10, 2024
Olive Heffernan’s The High Seas is an eye-opening journey into the lawless expanse of international waters, where ambition, environmental stakes, and geopolitics collide. Through meticulous research and vivid storytelling, Heffernan explores the exploitation of the ocean's resources — from overfishing to deep-sea mining — and the struggles to regulate this global commons.
Her skillful blend of personal stories, history, and policy analysis makes complex issues accessible and engaging. While some discussions of maritime law can feel dense, Heffernan’s passion and clear prose keep readers hooked. The book is both a stark warning and a hopeful call for international cooperation to protect one of our planet's last frontiers. Essential reading for anyone concerned about the future of our oceans.
Her skillful blend of personal stories, history, and policy analysis makes complex issues accessible and engaging. While some discussions of maritime law can feel dense, Heffernan’s passion and clear prose keep readers hooked. The book is both a stark warning and a hopeful call for international cooperation to protect one of our planet's last frontiers. Essential reading for anyone concerned about the future of our oceans.
January 5, 2025
A brilliant exploration as to how the ocean and our blue planet is interconnected to everything in our everyday lives and how we exploit it mercilessly.
As the book ended: “A healthy ocean, 30 per cent protected, could deliver the following: 20 per cent of the carbon emission reductions needed to achieve the Paris Accord's goal to limit warming to 1.5°C; forty times more renewable energy than was generated in 2018; six times more sustainable seafood; 12 million jobs; and $15,5 trillion in net economic benefits.” it’s important to realise how much industry, food, healthcare and day-to-day survival the ocean and the high seas actually give us. A really fascinating read for anyone interested in the sea, climate change or anything environmental related.
As the book ended: “A healthy ocean, 30 per cent protected, could deliver the following: 20 per cent of the carbon emission reductions needed to achieve the Paris Accord's goal to limit warming to 1.5°C; forty times more renewable energy than was generated in 2018; six times more sustainable seafood; 12 million jobs; and $15,5 trillion in net economic benefits.” it’s important to realise how much industry, food, healthcare and day-to-day survival the ocean and the high seas actually give us. A really fascinating read for anyone interested in the sea, climate change or anything environmental related.
October 7, 2025
You can tell that this book is written by someone who truly loves the ocean. The urgency and awe is noticeable in the writing! Sometimes it repeats itself a bit too much for my taste, but even then it's a wonderful, both broad and in depth, book
October 19, 2024
This was an informative and well-researched book about the transparency of what is going on in the depths of the ocean.
February 22, 2025
Some interesting information but needed better organization and editing.
April 22, 2025
“The High Seas” é um alerta escrito com precisão e fôlego jornalístico. Heffernan percorre o vácuo legal, ecológico e moral do oceano aberto, revelando como a ausência de soberania possibilita a superexploração, crimes e o colapso ambiental. Ao falar de peixes, redes e tratados, o livro aponta para algo maior: o custo de fingirmos que o que está longe não nos diz respeito. Uma leitura que constrói uma cartografia do abandono, amplia o horizonte e convida à responsabilidade.
September 27, 2024
In The High Seas, science journalist and former marine biologist Olive Heffernan takes a broad but deeply researched overview of the dangers facing the ecology of international waters around the globe.
Ranging from better known threats such as overfishing and deep-sea mining to more obscure but no less disturbing issues such as genetic data grabs and deliberate polar ice melts, Heffernan paints a picture of rampant corporations and powerful governments blithely ignoring international law (already very loose) in order to line pockets and ring-fence power and influence.
Told with a journalist’s clarity and brevity but also with an associated scientist’s sense of fury, the High Seas describes a present (and future) of unchecked capitalism rapidly changing and destroying essential oceanic ecosphere. As Heffernan points out, the scale of the destruction is so large that its distance from the shore becomes irrelevant. Everything that happens in the deep water now affects the wider planet, from melting ice caps to rising carbon in atmospheric gasses to reduced fish stock. There are some positive notes within, mostly highlighting the hard work of underfunded groups pushing back against the waste and destruction. But, the lack of accountability and flimsy law (where it even exists) means there is almost no apparent way to slow the process, much less stop it.
The book is a clarion call for us all to read about what is being done in the name of profits; profits that are not even trickling down to us. So much of the damage has no silver lining at all beyond the already overtstuffed pockets of a few corporate bosses. Read The High Seas and learn what is happening over the horizon and ask yourself whether you’re prepared to tolerate it.
(Proof copy supplied. Opinions my own.)
Ranging from better known threats such as overfishing and deep-sea mining to more obscure but no less disturbing issues such as genetic data grabs and deliberate polar ice melts, Heffernan paints a picture of rampant corporations and powerful governments blithely ignoring international law (already very loose) in order to line pockets and ring-fence power and influence.
Told with a journalist’s clarity and brevity but also with an associated scientist’s sense of fury, the High Seas describes a present (and future) of unchecked capitalism rapidly changing and destroying essential oceanic ecosphere. As Heffernan points out, the scale of the destruction is so large that its distance from the shore becomes irrelevant. Everything that happens in the deep water now affects the wider planet, from melting ice caps to rising carbon in atmospheric gasses to reduced fish stock. There are some positive notes within, mostly highlighting the hard work of underfunded groups pushing back against the waste and destruction. But, the lack of accountability and flimsy law (where it even exists) means there is almost no apparent way to slow the process, much less stop it.
The book is a clarion call for us all to read about what is being done in the name of profits; profits that are not even trickling down to us. So much of the damage has no silver lining at all beyond the already overtstuffed pockets of a few corporate bosses. Read The High Seas and learn what is happening over the horizon and ask yourself whether you’re prepared to tolerate it.
(Proof copy supplied. Opinions my own.)
Displaying 1 - 12 of 12 reviews