Salmon farm, U.S.
Credit: Department of Marine Resources, State of Maine.

Despite a wide recognition of fish sentience (see also do fish feel pain), there is little protection for farmed fish species. The World Organisation for Animal Health (OIE) recognises, in its policy statement, that:

“The use of fish carries with it an ethical responsibility to ensure the welfare of such animals to the greatest extent practicable”

and has published welfare guidelines on the transport and slaughter of farmed fish. However, most farmed fish throughout the world, and many in the EU, are handled, transported and killed by methods that do not meet these welfare recommendations and are not humane.

EU law recognises fish as sentient beings and gives theoretical protection during rearing and slaughter. The EU’s “AHAW” panel has published scientific opinions on the animal welfare aspects of husbandry systems for six farmed fish species (Atlantic salmon, trout, eel, common carp, seabass and seabream) and on the welfare aspects of the main systems of stunning and killing of eight farmed fish species (the above species, turbot and tuna). However, EU directives contain no detail regarding fish on permissible rearing conditions, such as stocking density or enrichment, or slaughter methods. Many existing commercial killing methods cause substantial suffering over a prolonged period of time.

The magnitude of the serious welfare problems in EU and global fish farming are multiplied by the large numbers of animals involved. It seems probable that the rising number of farmed fish slaughtered globally for food each year, estimated at between 37 and 120 (midpoint 80) billion* in 2010 (see estimate of farmed fish numbers), has already have overtaken that of farmed mammals and birds reported by the FAO at 63 billion that year.

In the EU, farmed fish numbers are lower but represent a significant proportion of farmed vertebrates slaughtered each year. EU farmed fish numbers are estimated at 460 to 1,700 million**, for which the mid-point of 1.1 billion equates to 15% of total EU farmed birds and mammals slaughtered in 2010 (most of these (86%) being chickens). Since the lifespan of farmed fish (typically ranging from a few months to over a year) is generally several times that of broiler chickens reared for meat (which are typically slaughtered at around six weeks of age) the numbers of animals in the EU alive at any one time may well be greater for fish than the combined totals for farmed mammals and birds.

Improving fish welfare in global aquaculture will require:

  • humane slaughter, transport and handling methods
  • environmental rearing conditions that both promote fish health and meet the ethological needs of the species
  • fish feeds based on trimmings and alternative feeds rather than purpose-caught wild fish.

Some key welfare issues in fish farming are discussed in the pages below. A fully referenced discussion of the welfare issues in fish farmed is available in the following paper:
Study to estimate numbers of farmed fish killed in global aquaculture each year (pdf 540 KB) 40 pages. July 2012.



* estimated range 36,734 million to 121,757 million (midpoint 79,246 million) rounded to 2 significant figures.
** estimated range 465 million to 1,699 million (midpoint 1,082 million) rounded to 2 significant figures.

1. Chapter 7.1. Introduction to recommendations for the welfare of farmed fish. 2010 OIE Aquatic Animal Health Code.