As ever, we begin with misinformation conveyed in breathless headlines, this time about emptying the oceans of fish. Not happening. OK, it was important to draw attention to overfishing, but not with falsehoods like this.
We will see virtually empty oceans by 2048.
Seaspiracy, 2021
In 2006, Boris Worm and his co-authors published a paper in Science…The media…homed in on a single statistic.
It projects the global collapse of all taxa currently fished by the mid-21st century.
But “global collapse” does not mean “no fish left”. In the language of the science, it means that catches will fall to 10% of current levels.
Bad enough, certainly. But even then we know how to recover by systematically reducing catches, establishing protected areas, especially around spawning grounds, and looking for the causes of collapse among different kinds of fish.
[Worm] estimated that in 2003, almost 30% of the world’s fish stocks were defined as collapsed. What he then did was simply extend that trend line out until it reached 100%.
This is complete statistical bogosity. Such a mathematical projection cannot be taken as reality. It is a decent first approximation, if you use it to point out the vastness of our ignorance. Then you have to take the trouble to gather real data, consider other factors including possible measures to restore fish stocks, and build a real model.
There’s no excuse for getting this wrong today…That’s because this controversy sparked a revolution of fisheries data.
Ray Hilborn…responded with a paper in the journal Fisheries, titled Faith-Based Fisheries.
They were both invited to talk it out live on US National Public Radio…It turned out more amicable than expected. Hilbert and Worm shared a lot of common ground.
It became clear that the data set needed to really understand what was going on hadn’t been built yet. They decided to team up and construct it…The mission was to gather and aggregate data on fish abundance—the number of fish in the ocean rather than the number being caught…
By 2009 they had the data they needed. Their co-authored study—titled Rebuilding Global Fisheries—appeared in Science…
What their results showed was that, on average, there was no decline in these fish stocks. But they did find different results over different regions. Some stocks were doing well, and were in fact increasing. Others were struggling and were a cause for concern.
The history of fishing and whaling goes back thousands of years or more. Depletion of fish stocks was not a concern until the 19th century, with revolutions in fishing technology such as huge gillnets that swept up everything, and later steam-powered trawlers.
Cod fishing peaked in 1968, and then crashed, closing down completely in the early 1990s. In another familiar story,
Many countries have learned how to manage their fish stocks much more sustainably. Endangered fish stocks have made a comeback. But unmonitored and unregulated fishing techniques—where large amounts of fish are caught indiscriminately—are increasing across some parts of the world.
As usual, there is good news mixed with bad but not catastrophic news.
There are two main schools of thought when it comes to fish. One school views fish as animals in their own right. We should allow populations to increase back to their historic levels. The other school views fish as a resource. So ‘sustainability’ according to this view means catching as much fish as possible, year after year, without depleting fish populations any further.
Scientists can calculate this magical ‘sweet spot’…It’s called the ‘maximum sustainable yield’…When a fish stock is at its ‘maximum sustainable yield’ it’s around half its original, pre-fishing level.
In the early 1970s, close to 90% of the world’s fish stocks were being managed sustainably…By the early 2000s, around one-quarter of the world’s fish stocks were overexploited. By 2008, this had risen to one-third. Since then...it has stayed at one-third. This means that two-thirds of global fish stocks are managed sustainably.
Since 1990, global seafood production has more than doubled [through] aquaculture…The world now produces more seafood from fish farming [100 million tonnes] than it does from wild catch in the oceans.
So we know what works, and next we have to make sure that every country does it.
- Corals are getting bleached to death
Stop global warming. Don’t take half measures.
- Eat less fish, and only the kinds being sustainably managed
There are a number of seafood guides that do a good job of giving recommendations. In the UK the Marine Conservation Society’s Good Fish Guide is my go-to. In the US, the Monterey Bay Aquarium’s seafood watch is the best. Other countries have their own guides.
- Implement strict fishing quotas
This depends first on getting good estimates of the sizes of fish stocks.
Good management of fisheries can work.
If based on good science, and carefully monitored.
This situation is a perfect reflection of the three-true-statements: things are awful, things are much better, things can be improved…An end to overfishing is well within our reach.
- Strict regulation on by-catch and discards
Some countries have implemented a ban on discards at sea. This is sometimes called a ‘landing obligation’ which means that fisherman must keep all their caught fish on board and declare it as ‘landings’…If fisherman have a quota or limit on how much fish they can catch, they have to be much more careful about ‘by-catch’—these unwanted fish will still count toward their quota for the day.
Thus you give fishermen and corporations that process fish real incentives to reduce ‘by-catch’.
- The carbon footprint of fish, wild-caught or farmed, is much less than any livestock on land
Many vegetarians and vegans won’t like this, but even we have to allow most of the population of the Earth animal protein, sustainably raised and managed. Even Buddhists don’t try to tell laymen they can’t have meat or fish or dairy.
