New breakthrough in sustainable fish farming

Scientists from the Centre for Environment, Fisheries and Aquaculture Science (Cefas) have developed pheromones which trigger feeding behaviour in fish. This technology can be applied to the aquaculture industry to make farmed fish eat a more environmentally-friendly diet, and consequently make the industry more sustainable.

The scientific break-through was revealed in an exclusive report to BBC One’s Countryfile (3rd November 2002).

“We hope that this will certainly revolutionise fish farming worldwide” says Dr Andy Moore from the Cefas Laboratory in Lowestoft, Suffolk.

One of the chief criticisms of fish farming is that species such as salmon, trout and cod, have to be fed large amounts of wild fish such as sandeel. It takes up to three tonnes of wild fish to produce one ton of farmed salmon and up to five tonnes to produce a ton of farmed cod or haddock. This has knock-on effects on the already depleted wild fish stocks. Sandeels are major prey items for a number of birds and fish, including cod. This is not sustainable, something which the fish-farming industry itself recognises.

“It will certainly have an impact on the amount of fishing that’s done to take fish specifically to feed fish in the aquaculture industry. We’re very much trying to save and conserve fish stocks around the world.” Dr Andy Moore.

Dr Moore and his colleagues have identified pheromones which are released by fish and induce feeding behaviour in other fish. They have now developed synthetic versions of the pheromones and by adding the compounds to the water, fish begin to search and will eat any food item present.

“A pheromone is a compound released by one fish detected by another fish normally by the sense of smell. It brings about specific responses such as migration, and is involved in reproduction, predator-prey interactions. So it’s a form of chemical communication between fish. We’ve been finding over the last two years that there are specific pheromones that do encourage fish to feed.” Dr Andy Moore.

Since the pheromones are naturally produced in the water by the fish it will not have an impact on the fish’s health nor the wider environment. The chemicals have already had some application for sports angling (Ultrabite?), but the core pheromone technology will now form the basis for the development of sustainable products for the commercial and aquaculture industries.

Cefas intends to work closely with the aquaculture and fish-food manufacturing industries to make fish-farming and fisheries sustainable. Worldwide trials are due to start early next year and the scientists hope that the pheromone technology will go a long way towards preserving declining fish stocks around the world.

Contacts

Andy Moore (Cefas) 01502 524212
Nicola Lower (Cefas) 01502 524209

Cefas Lowestoft Laboratory
Pakefield Road
Lowestoft
Suffolk NR33 0HT
Tel: +44 (0) 1502 562244
Fax +44 (0) 1502 513865

Notes to editors

Cefas is a scientific research and advisory centre for fisheries management and environmental protection. It provides contract research, consultancy, advice and training in fisheries science and management, marine environmental protection, aquaculture and fish and shellfish disease and hygiene to a large number of public and private sector clients around the world.

Cefas is an agency of the UK Government’s Department for Environment, Food and Rural Affairs (Defra). Cefas employs over 550 staff at four sites around the UK

Pheromones act as chemical signals and a method of communication between fish in an environment where vision is often restricted. Pheromones play a pivotal role in the biology of fish and are involved in reproduction, shoaling, feeding and migration. The pheromones are released by the fish in minute quantities and are detected by other fish using the sense of smell.

Cefas has been involved in pheromone research for 15 years and has previously identified and characterised a wide range of pheromones that are involved in attracting and synchronising reproduction in freshwater and marine fish.

Most worldwide fish stocks are overexploited and it is unsustainable to base aquaculture on increasingly limited and expensive fish protein. In addition, intensive aquaculture leads to much waste and harmful impacts on the aquatic environment.

Development of pheromone based products will allow aquaculture to move away from unsustainable fish based feed by making more environmentally friendly forms of protein palatable to fish.

Development of these pheromone-based products will increase feeding and food conversion, reducing the amount of fish based feed required and the subsequent impacts on the environment.