Kate Fowler finds that our dietary choices can have a huge impact, not just on ocean wildlife, but on the climate change that is affecting the whole planet
The oceans are in trouble. Before the industrial revolution, they were a net source of carbon dioxide, but since humans started emitting vast amounts of climate-altering gases, the oceans have been absorbing it.
In the last decade alone, they have absorbed a quarter of the Earth’s greenhouse gas emissions and are now considered a vital carbon sink.
Forcing the oceans to take on this role has come at a heavy price. Seawater temperatures are increasing, glaciers and ice sheets are melting, sea levels are rising, and the waters are becoming more acidic.
These changes are having a devastating impact on the lives of animals and the balance of ecosystems beneath the waves.
Animals have become displaced; patterns of migration have altered; and for some species there is a greater incidence of disease. Underwater cultural heritage sites are being damaged and lost, with coral bleaching, coral disease and coral death increasingly common.
“A report by the IMF found that saving whales would actually have a bigger climate impact than planting trees.” Photo © willtu via Adobe Stock
The increased acidity of the water is weakening the skeletons and shells of animals, leaving crustaceans particularly vulnerable, while also reducing growth and survival rates of certain species.
As the waters warm, even to a depth of 1,000 metres now, oxygen levels drop, and that places additional pressures on marine creatures.
Us land-dwelling animals may be more aware of the forest fires, heatwaves and destructive storms that occur around us, but the climate impact within the water is every bit as serious.
How eating fish drives climate breakdown
Our production and consumption of animal products is a leading driver of climate breakdown, but while the impact of beef, dairy and other animal products have become increasingly well known, the fishing industry has largely escaped scrutiny. And yet, in terms of climate impact, this is a wholly damaging sector.
For a start, ships are incredibly polluting. Half of the UK’s fishing fleet is at least 30 years old and uses a kind of oil that is particularly damaging for the climate. And then comes the impact of the tens of thousands of trawlers, dragging vast nets along the ocean floor, ripping it up and disturbing the sediment where carbon is stored.
In terms of the impact, this is definitely not small fry. Trawlers are responsible for releasing one gigaton of carbon every single year, which is equal to the emissions from the entire aviation industry.
"Trawlers are responsible for releasing one gigaton of carbon every single year, which is equal to the emissions from the entire aviation industry." Photo © Vincent via Adobe Stock
Eating farmed fish is not a solution to this, as those trawlers ploughing up the ocean floor are also catching fish to feed to captive-bred fish in farms, meaning aquaculture must shoulder some of the responsibility.
Yet another significant impact comes from those farms themselves. Oxford University research found that fish farms are powerful emitters of methane due to the perfect conditions at the bottom of the ponds where unconsumed feed and waste collect.
This is one reason why eating farmed freshwater fish, such as shrimps and prawns, has three-and-half times the climate impact of eating tofu.
And then comes the fourth climate impact of fishing, and perhaps the most surprising of all, which relates to the removal of vast numbers of fish and other aquatic animals from the wild.
Fishing farming emit large amounts of methane and decimates wild fish populations causing significant damage to ocean ecosystems. Photo © 22Imagesstudio via Adobe Stock
Fishing, by-catch and climate breakdown
By-catch – the capturing of non-target species – is an inevitable consequence of fishing. Those vast nets cannot discriminate between the species of fish that the ship set out to catch and non-target animals, including whales, sharks and dolphins.
They simply scoop up any creature unlucky enough to be in their path. Millions of large sea animals – as well as turtles, rays, starfish and diving seabirds – are also caught and killed.
This is obviously a serious matter for the animals themselves and for the balance of the ecosystem, but it is also a serious matter for the climate. This is because these large animals are important carbon sinks; they collect carbon in their bodies.
If they die in the ocean, their bodies sink to the bottom, taking the carbon with them, but when we remove millions of these large animals from the water each year, we remove their capacity to capture carbon, and this has a much bigger impact than we might imagine.
A 2019 report by the International Monetary Fund found that saving whales would actually have a bigger climate impact than planting trees.
Capturing non-target species is an inevitable consequence of fishing as vast fishing nets catch millions of large sea animals like turtles, rays, starfish and diving seabirds who cross their paths. Photo © Placebo365 via Getty Images
Ocean-based climate action can play a major role in reducing the world’s carbon footprint and deliver up to 21 per cent of the annual greenhouse gas emission cuts pledged by the Paris Agreement.
Despite this, governments are not taking seriously the role of the oceans in preventing climate breakdown or how much they are suffering because of it.
Any recommendations that are made continue to treat the oceans as a product to be exploited and monetised, rather than a natural ally in the prevention of climate catastrophe and the reversal of decimated biodiversity.
Currently, less than eight per cent of the ocean is protected.
Governmental inaction means that less than eight per cent of the ocean is currently protected, and it's wreaking havoc on biodiversity. Photo © Sirachai Arunrugstichai via Adobe Stock
We need to let the oceans heal, and the biggest thing we as individuals can do to help them is to stop eating fish. When we withdraw our support for this industry, trawlers stop ploughing up the ocean bed, destroying ecosystems, releasing climate-changing gases and removing large carbon-absorbing animals from the waters.
Populations can recover, the seagrass meadows, mangroves and kelp forests can recover, and each can store more carbon. It is the right thing to do for the animals with whom we share the planet, the planet itself, and for ourselves.
The damage already done cannot easily be fixed. It will take more than 700 years to fully reverse the acidification of the waters, such is the extent of the pollution already caused, but that is all the more reason why we should start now. The oceans can save us, but we must save them, too. Our lives and wellbeing are tied up with theirs.
Are you ready to quit eating fish to save the ocean? These cruelty-free vegan fish recipes taste like the real deal!
Featured image credit: by wildestanimal via Getty Images