Reducing the numbers of fish caught
I. Reduce the numbers of fish caught wastefully or illegally
II. Catching smaller numbers of fish and catching them larger
III. Reduce the numbers of fish caught not directly for food
Reducing numbers of fish caught wastefully or illegally
Many fish are caught wastefully. Wasteful deaths include the fish caught unintentionally as bycatch (wrong species or size) and are then thrown back into the sea, dead or dying. In 2005, the FAO estimated that 7.3 million tonnes, or 8%, of fisheries capture was discarded each year for the years 1990-2001. In addition, an uncalculated number of fish die following escape from trawl nets. Another way in which fish are caught wastefully is in the killing of fish by lost or discarded fishing gear i.e. “ghost fishing”.
Ways of reducing the numbers of fish caught as bycatch and by ghost fishing, and increasing the survival chances of discarded bycatch fish and fish escaping trawl gears, are discussed in the pages on capture methods.
The management of fisheries can only be effective if regulations are enforced. Illegal, unreported and unregulated (IUU) fishing is a global problem. Each year, illegal fisheries capture an estimated 11.06 to 25.91 million tonnes of finfish and shellfish, compared to the 94.5 million tonnes of average annual recorded capture in 1999-2003.
Catching smaller numbers of fish and catching them larger
The suffering of wild catch fish could be reduced by a strategy to catch fewer fish, and to catch them larger so that fewer fish are caught for the same amount of food. There are other good reasons for pursuing such a strategy besides those of animal welfare. Many argue that reductions in fishing effort are necessary for managing the world fisheries sustainably. It is also argued that fish are being caught too young and need to be allowed to spawn and to grow larger before being caught, in order to maintain or rebuild fish populations. The economic benefits from fisheries might be increased by setting fishing levels even lower than those required for biological sustainability, since increasing the relative abundance of fish reduces the fuel (and hence carbon footprint) and labour costs of catching them.
Overfishing is a serious problem in world fisheries. Overfishing reduces abundance of individuals in a fish stock, by removing fish faster than can be replaced by breeding. If continued, it can lead to a collapse of that fishery, as happened with the Newfoundland cod fishery in the 1990s. Overfishing tends to reduce the size of captured fish over time, leading to increasingly larger numbers of smaller fish. This exacerbates the welfare cost of fishing.
Many scientists, and conservation groups such as Greenpeace, argue that fisheries management needs to adopt the precautionary approach. They argue for reductions in fishing effort as well as the creation of no-take marine protected areas (MPAs). These have the advantage over setting fishing quotas as a means of restricting fishing effort, in that they do not result in catch being discarded because it cannot be legally landed. Selective fishing gear is a means of capturing only those fish within the optimum size range in order to reduce “growth overfishing” (capture of fish before they have fully realized their growth potential) and “recruitment overfishing” (capture of immature fish before they can spawn).
Reducing numbers of fish not directly caught for food
Between a quarter and a third of fish capture, by tonnage, is caught for reduction to fish oil and fishmeal. This is known as “industrial” fishing. Fishmeal and fish oil are used largely for animal feed, mainly for farmed fish. fishcount.org.uk estimates that in the order of a trillion (0.97-2.7 trillion) fish are caught each year. A substantial proportion of these are used to make fishmeal and fish oil used to feed to farm animals (and other non food purposes) or fed whole to farmed fish. Our estimate of the number of fish caught to make fishmeal and fish oil each year, at around 0.5-1 trillion, is shown here (expand the window to view).
Further uncalculated numbers of fish are used as bait in catching other fish.
Increasingly this industrial fish catch is being used to feed farmed fish such as salmon. Small feed fish suffer a stressful death, one that would fail any standard of humane slaughter, to produce a miniscule amount of food. It takes 3-4 kg of wild fish to produce 1 kg of salmon. Fish used to make fishmeal vary in weight from 10g (e.g. sandeels) to 1000g (e.g. a jack mackerel). To take just one example a Peruvian anchovy, weighing 20g, is killed inhumanely to produce approximately 6g of salmon flesh.
Environmentalists are concerned about the ecological impact of the removal of large numbers of these small fish from the ocean, e.g. how it affects the fish, seabirds and other marine wildlife that feeds on them.