One of the greatest challenges the world faces is ensuring that a growing global population has enough to eat.

Food production needs to increase by 50% to feed a projected population of 10 billion in 2050, according to the UN’s Food and Agricultural Organisation.

Fish is a crucial source of nutrition for billions of people, providing easily-to-digest protein that is especially helpful in fighting micro-nutrient deficiencies.

Against this backdrop, it seems crazy that so much fish - about 35% - is simply wasted.

Dumped in the sea

Large trawlers account for about one-quarter of that wastage, according to the Guardian. Unwanted fish are thrown back into the sea - already dead - because they are either too small or from an unwanted species. The FAO wants some of that bycatch to be used to produce fishmeal, rather than simply being discarded.

Most of the waste, however, comes from developing countries, where fish simply rots before it can reach a factory or marketplace. The FAO says that 27% of fish that is landed is never consumed.

This is because local fisherman do not have the knowledge or equipment - such as refrigeration or ice-makers - to keep their produce fresh.

The FAO has worked with fisherman to reduce such waste, including encouraging the use of raised racks for sun-drying fish on the banks of Lake Tanganyika in Burundi, or reducing the bycatch when bottom trawling to catch shrimp in Brazil.

More people are eating more fish
Image: UN FAO

Beating hunger

The statistics about fish wastage are featured in a two-yearly report, which surveys the state of the world’s fisheries, detailing how much fish is being caught and eaten.

Fish consumption and production has been rising fast, peaking at about 171 million tonnes in 2016, and growing faster than other sources of protein such as meat.

Much of the growth is due to the steady rise of aquaculture - that is the farming of fish rather than catching wild fish - as shown in the chart below. In fact, aquaculture accounted for 46.8% of all captured fish, an enormous rise from 25.7% in 2000.

The rise in fish production is primarily thanks to farming
Image: UN FAO

Aquaculture is one way of preventing overfishing, although it needs to be done sustainably with a close watch on the type of marine life that is used as feed. Aquaculture can also help mitigate the impact of climate change, where warmer waters are changing the patterns of behaviour and undermining traditional livelihoods.

Overall, the growth of aquaculture has meant that fishing in the wild has now decreased slightly, falling to 90.9 million tonnes in 2016, a drop of two million from 2015.

Reducing plastic waste

Global fishing employs 60 million people around the world, and is a source of nutrition for many many more, providing around 3.2 billion people with nearly 20% of their animal protein needs.

Fish stocks must be protected for future generations
Image: UN FAO

The FAO’s Director-General Jose Graziano says fish are “crucial” in meeting the goal to create a world without hunger and malnutrition.

But the way we treat fish and the oceans will need to change to meet that goal.

More regulation and monitoring of responsible fishing practices is needed should include a strong emphasis on the prevention of over-fishing.

Increased effort to protect the world’s oceans, where alarming amounts of trash are destroying ecosystems, is also needed. A World Economic Forum’s report warns that, without action, by 2050 there will be more plastic in the ocean than fish, measured by weight.

And there needs to be much less waste of the fish that is caught.

Only by taking action on all three fronts will there be enough to feed future generations.