It is already known that fishing damages entire ecosystems and pollutes our oceans. So would we be better off without it?
On average, we each eat more than 20 kilograms of fish every year. Worldwide, between 1961 and 2016, fish consumption increased faster compared to meat consumption, becoming more and more popular, growing twice as fast as the human population.
All of these fishy meals have used up marine fish stocks to a point where a third of our global fish stocks are now ranked as ‘overfished’. If we continue fishing at the same scales, these fish populations will continue to decline. Most of the rest are being exploited at the maximum levels that can be sustained without long-term decline.
Additionally, fishing has negative effects upon non-food species in the ecosystem, polluting the water with fishing waste. Temporary fishing bans may help to alleviate some of the worst impacts, but what would happen if we banned fishing altogether?
1. Millions would struggle to eat and earn enough
Around the world, there are more than 40 million people who earn their living directly from fishing, while another 19 million are working in aquaculture, fish-farming or growing seafood in controlled conditions such as sea pens and cages, lochs and ponds.
But these numbers may hide how much our planet depends on fishing. Around the world, estuaries and coral reefs, millions of small-time fishers make poor earnings from fishing, while many catch fish just to put food on the table for their families. Moreover, some fishers don’t make the stats, and neither do their catches.
“A lot of the small-scale catches are distributed in informal markets, where they’re not recorded,” says marine ecologist Dr. Steven Purcell at Southern Cross University in Coffs Harbour, Australia. His own studies suggest that 71 percent of those fishing for Trochus sea snails in the Samoan islands eat them themselves or give them away to friends and neighbors.
Seafood is a major source of protein across Southeast Asia and islands in the Indian and Pacific Oceans. So while in Europe or the US people could definitely eat more meat or soy products as a protein source, a possible fishing ban could lead to food scarcity in communities with little land-based farming.
We can already imagine a black market developing for fish, as they’re currently is for beluga caviar in the United States, where it is banned. Eggs from the endangered beluga sturgeon are thought to be brought in privately only to top Manhattan chefs. If fishing would be banned, you shouldn’t think about caviar anymore, but more about ordering canned tuna from the black market.
2. Seafood farms could step up to meet demand
Aquaculture already produces about half of the seafood we consume (or more, if you include seaweed), but we’ll be forced to increase that if we are to avoid annihilating wild fish stocks. If we would ban fishing, aquaculture could become our only source of seafood, meaning that, initially, we’d be eating a lot of Atlantic salmon, which is by far the most farmed fish across Europe.
“Wild fisheries allow you a diversity of products that aquaculture would probably take many years to get to,” says Dr. Sofia Franco at the Scottish Association for Marine Science. But she hopes to see a wider range of farmed seafood on the menu in the future, as expertise in different species and farming systems develops.
Until now, production has been mainly in farms open to the sea, rivers, or lochs. Newer, land-based systems, such as tanks with recirculating water, could help in reducing the pollution and damage to aquatic environments compared to the older systems.
But could you supply all the world’s fish suppers without using a drop of actual seawater? Dr. Rebecca Gentry, a marine scientist at Florida State University, suggests we wouldn’t need to do that. Additionally, aquaculture in the sea could produce the equivalent of the world’s fishing catch in less than 1 percent of the ocean surface, her 2017 paper shows.
“It’s an interesting thought experiment,” she says. “If we close all wild fisheries, look at this huge amount of ocean area that we’re no longer having an impact on.”
3. Stocks would recover, but not all of them
Temporary bans on fishing regarding certain species are already used worldwide to help to maintain fish stocks and protect the environment. Some temporary bans only last a few weeks while other last a few months every year. These seasonal bans were implemented to protect fish during their breeding season and to protect the sea bottom from damage, as with shrimp trawling bans. Other bans can last more than a year, or even longer, as in the current moratorium on fishing in the Arctic, which could last up to 16 years.
A total global fishing ban would increase stocks while helping to rebalance damaged ecosystems. For example, eating less lobster thermidor would help keep seaweed forests in good health, as the crustaceans prey on sea urchins that destroy kelp, which is a type of seaweed.
However, banning fishing doesn’t guarantee a full recovery in our oceans. According to Purcell, some species are already so badly affected by overfishing that they might never recover. In Papua New Guinea, the edible sea cucumbers that he studies, which are popular in Asian cuisine. Sea cucumbers have been so voraciously harvested that their populations are down to one-hundredth of their pre-fishing levels.
“Once they get down to less than one animal per hectare, it’s very hard for the mates to find each other, particularly for these species that aren’t moving very fast,” Purcell says. “They have to crawl around on the seafloor to find each other.”
Nevertheless, in the north of Australia, some shellfish populations exploited by Indonesian fishers have declined so much that only a few are now reproducing and rebuilding their populations seems almost impossible.
4. The oceans would be cleaner
Recent years have seen single-use plastics reflected poorly as the public has woken up to the effects of marine plastics. But few people realize what an impact fishing makes. Lost fishing gear accounts for about 10 percent of all marine litter and, according to a 2018 study, 86 percent of the big pieces of plastic floating in the ‘Great Pacific Garbage Patch’.
Without fishing, we have the chance to eliminate the pollution and emissions from fishing boats, considering that one 2014 study claimed that lobsters were the most fuel-intensive species, with some boats using 20,000 liters of fuel to catch a single tonne.
However, a negative aspect would be that aquaculture could also bring other sources of pollution, such as feed and chemical products that are used to control the disease. These pollutants enter the sea where fish are farmed in pens and cages. Franco says that aquaculture is, at least in some sectors, less polluting than it was. “Consider salmon farming in the UK – antibiotics have not been routinely used in years,” she says. “But regulations and conditions can be very different in different sectors and countries.”
Nevertheless, the global aquaculture needs to become more sustainable if the farmers want to access the most valuable markets, as these demand higher standards.