Sushi is wrecking the planet.
It may sound like hyperbole, but unfortunately it is not. While this popular repast is not alone in the endeavour, stated plainly, sushi is one of the most environmentally damaging foods one could possibly eat. About all one can say in its favour is that very little of it is made with beef.
Let’s start with the basics.
All sushi is made with rice; lots of it. That’s not good. It may surprise you, but rice is in the same league as beef when it comes to global warming.
Most people know these days that beef cattle are among the biggest emitters of global warming gases on earth. One hundred million tonnes of methane are belched from these cows and bulls every year. What most people don’t know is that rice is just as bad.
One hundred million tonnes of methane seep from rice paddies, too, the latest studies tell us. Depending on whether you count methane’s effects over 100 or 20 years, that’s the equivalent of between 2.3 and 7.2 billion tonnes of CO2 flowing into the atmosphere from the cattle and another 2.3 to 7.2 billion tonnes of CO2 from the rice we produce each year. Together they are emitting the methane equivalent of one-fifth to two-thirds of all of the carbon dioxide from all of the fossil fuels we burn across the world every year.
Of course, as it is the staple food of the bulk of humanity, rice feeds an awful lot more people than beef does, and its production involves a lot less animal suffering. But it is still a very bad player in the climate crisis.
It would be bad enough if the damage associated with sushi were limited to this rice-based acceleration of global warming. But, of course, rice content is only a small part of the sushi problem. Being composed largely of fish, sushi’s popularity is enormously more damaging than that.
The harvest of fish that fill the sushi we eat is playing an enormous role in the decimation of the world’s oceans. As the World Wildlife Fund tells us, Atlantic populations of bluefin tuna – the most popular sushi fish – have dropped 80 percent since 1978. In 2009, one million of these giant predators were plucked from the sea. Since the total population of these fish is estimated at 3.75 million and it takes 10 to 12 years for these tuna to reach sexual maturity, the prospects for these fish are extraordinarily bleak.
Other species are similarly affected. Worldwide, the scale of ocean fishing has increased enormously in the last 60 years. In 1950, a total of less than 30 million tonnes of fish were pulled from the sea, including illegal and unreported catches. By 1990, this had surged roughly 6-fold to 180 million tonnes, some 30 percent of which was illegal. Not surprisingly, the populations of the fish in the sea are way, way down. This is especially true of the big ones – tuna, cod, halibut, swordfish, shark, flounder – which are down more than 90 percent from their 1950 levels. Fishing at this intensity cannot be maintained; despite an ever-growing fishing fleet, the annual catch is now down to about 140 million tonnes. By 2050 scientists predict that the seas will be pretty much empty.
We and our sushi habit are driving this decimation. Eighty percent of all the fish caught in 2006 were eaten in the developed world. In North America and Europe, we eat an average of well over 40 lbs of fish per person each year. This is the highest aggregate level of fish consumption in the world. With over 1 billion Europeans and North Americans, our total consumption dwarfs that of even Japan whose 127 million people consume 57 lbs each.
What can we do about it? Since it seems that the world’s governments are incapable of responding to this crisis – astonishingly, Japan managed to block a proposed ban on the trade of even the most endangered bluefin tuna – it is up to us. If ocean life is to be saved, we’re going to have to stop eating sushi and pretty much all other fish. If we don’t do it now, we certainly will do it later – when there are no fish left to eat.
David Steele is a molecular biologist at the University of British Columbia and President of Earthsave Canada.