Brute Ethics





Animal Ethics Encyclopedia

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Fishing - Farming

Fish farming, also called aquaculture, is the production of fish and aquatic plants in big tanks on land or in pens floating in a lake or estuary. Aquaculture extends back at least 2,400 years when the Chinese reared carp in ponds. The industry today approached nearly 30 per cent of world fish production in 2001 and is still growing. Among the popular edible farmed fish are salmon, carp, trout, cod and halibut. Shellfish include oysters, mussels, scallops and clams. Aquaculturists also farm ornamental fish and farmed plants include hyacinths, seaweed and water lilies.

Claims In Favour

  • Fish farming fills a growing demand by an increasing human population for more fish and fish by-products.

  • Fish farming helps conserve endangered or over-fished populations, taking pressure off them by restocking depleted lakes, rivers and coasts. Lobsters, rare around some coasts, for example, can be replaced with juveniles reared in hatcheries and transported to the seabed.

  • Claims Against

  • Fish are given drugs against diseases and parasites and are given hormones to quicken growth and make them big. People who eat the fish ingest toxic residues of these chemicals.

  • Crowding induces tail and fin nipping and cannibalism.

  • Farmed fish who are used to restock lakes and rivers are reared in a barren environment where they cannot learn to survive. Most die when released because they cannot recognise, capture or handle live prey, and their lack of experience makes them vulnerable to predators.

  • Farmed fish feed on wild fish caught in the sea. Five kilograms of wild fish can go to produce one kilogram of farmed fish. This is poor economic value and is at the expense of wild fish.

  • Many fish farms use anti-predator nets. Birds, seals, sea lions, dolphins and porpoises get entangled in them and drown.

  • Some fish farmers kill fish-eating animals they see near their fish pens: predatory fish, fish-eating birds, like cormorants, herons, kingfishers and pelicans, and mammals, like mink, otters, sea lion and seals, plus crabs and starfish (both of which eat oysters).

  • Fish are given drugs against diseases and parasites and given hormones to quicken growth and make them big. People who eat the fish ingest toxic residues of these chemicals.

  • Statistics

    The worldwide total of farmed fish, 38 million tonnes, amounts to 22 kg of fish per person worldwide and is a 38 fold increase since 1950, when about one million tonnes was farmed.

    The Table below lists the top five fish farming counties in 2001. China produces two-thirds of the world total of farmed fish. Not shown in the Table are the US, which ranked 10th at 0.5 million tonnes ($0.8 billion value), and Britain, which ranked 19th at 0.2 million tonnes ($0.5 billion value).

Table: Farmed Fish in 2001
Top producers, tonnes & value.
World Total 38 million tonnes US $
China 26.1 million tonnes 26.2 billion
India 2.2 million tonnes 2.5 billion
Indonesia 0.9 million tonnes 2.4 billion
Japan 0.8 million tonnes 3.4 million
Thailand 0.7 million tonnes 2.4 billion

Source: S Vannuccini (2003): Overview of Fish Production, Utilization, Consumption and Trade. Food and Agriculture Organization of the United Nations, Fishery Information, Data and Statistics Unit. Data include shellfish. 1 tonne = 1 ton.

The World's Three Most Farmed Fish/Shellfish
(by weight)

1. Pacific king oyster (Crassostrea gigas).
Also called Japanese oyster.
4.2 million tonnes in 2001.
Usually 8 to 30 cm long (8 to 12 inch), a filter feeding oyster favouring shallow waters, introduced around the world from Japan. Reared primarily in estuaries.

2. Grass Carp (Ctenopharyngodon idellus).
3.4 million tonnes in 2001.
Grows up to 1.5 m and 45 kg (5 foot and 90 lbs). Lives in lakes and rivers. Original home was China and eastern Siberia and now introduced around the world. Feeds on plants and invertebrates. Maximum reported age is 21 years.

3. Silver carp (Hypophthalmichthys molitrix).
2.9 million tonnes in 2001.
Grows up to 1.0 m and 50 kg (3 foot 3 inch and 110 lbs). Enjoys slow flowing waters of large rivers. Original home China and eastern Siberia but introduced around the world. Feeds on phytoplankton and zooplankton.

Tonnage data from: Food and Agriculture Organization of the United Nations, Fishery Information, Data and Statistics Unit. 1 tonne = 1 ton.

For & Against: argue your case

  • Claim: Fish farms pollute the sea by discharging waste (eg uneaten food and faeces), pesticides and other chemicals into it.

  • Claim: Waste from fish farms is dilute, consisting of normal fish faeces and small amounts of uneaten food suspended in large amounts of water. It is to the advantage of aquaculture to protect and not pollute the surrounding water from contamination.

  • Drugs
  • Claim: Farmed fish need drugs to kill bacteria which cause infections. Dosing the fish with antibiotics creates bacteria resistant to treatment that would normally kill them. Resistant bacteria then spread through the water to infect other animals and people handling the fish by getting into open wounds or abrasions.

  • Claim: Fish, as with any farmed animal, require periodic treatment. All medication is properly approved by the relevant authorities and administered by vets.

  • Salmon Colouring
  • Claim: Salmon are given chemicals to change their colour to match the natural pink flesh of wild salmon and make them look appetising. The residues of these chemicals are hazardous to people eating the fish.

  • Claim: Farmed salmon are fed naturally occurring pigments to reflect the diet of wild salmon. The additives are officially approved for use and there is no evidence that they are harmful to anyone.

  • Water Use
  • Claim: Fish farming on land uses excessive amounts of water. In coming decades conflicts over fresh water availability will increase as fresh water becomes a scarce and precious resource. Fish farming exacerbates the problem.

  • Claim: Water is not consumed but is generally returned to the environment after use. It flows through raceways, sometimes covered to reduce precipitation, and is treated to remove solid wastes before it is discharged.

  • Genetically Modified Fish
  • Claim: Virtually no scientific data exist to show that genetically modified farmed fish are safe for the environment and human health.

  • Claim: Nor is there scientific data showing they are unsafe. Genetically modified farmed fish would increase farmed fish production, minimise waste discharge and the need for chemicals.

  • Also see:

    Fishing - Angling

    Fishing - Deep Sea

    © 2004 Roger Panaman All rights reserved