The farming of flatfish including flounder, turbot, and halibut has been associated with a number of environmental impacts, such as the use of marine ingredients in feed, negative impact on biodiversity, use of antibiotics, disease and parasite transfer, and impact of pollution on water quality and the seabed. ASC certified flatfish farmers work hard to improve standards in their industry, work with their local community, and respect their workers and the environment.

The ASC Flatfish Standard is applicable to Flounders (species in the genus Paralichthys), Turbot (species in the genus Scophthalmus) and Halibut (species in the genus Hippoglossus) and in all regions globally where these fish are farmed.

ASC’s programme requires farms to be independently assessed and to provide an unparalleled level of transparency by making all the audit reports publicly available on its website. Here is what makes ASC certified flatfish a responsible choice, helping you to care for the natural environment and support local communities:

  • Biodiversity

ASC certified flatfish farms minimise impacts on the local ecosystem in a number of ways, such as the development and implementation of an impact assessment to protect wildlife and sensitive habitats, protection of the ecological quality of the seabed, ensuring farms are not sited in High Conservation Value Areas (HCVA). Certified farms must greatly minimise any fish escapes. All lethal incidents with wildlife must be reported to the ASC.

  • Feed

ASC certification requires flatfish farms to adhere to strict limits to minimise the use of wild fish as an ingredient for feed. In addition, the standard requires farms to ensure full traceability back to a responsibly managed source, preferably certified, both for wild fish and non-marine ingredients including soy and palm oil.

  • Pollution

ASC certified flatfish farms are required to measure various water parameters (phosphorus, oxygen levels, etc.) at regular intervals and remain within set limits. Potential copper release into the water must be minimised and monitored.

  • Diseases

ASC certified flatfish farms are required to adhere to rigorous requirements to minimise disease outbreaks. A Fish Health Management Plan detailing steps for biosecurity management must be developed under supervision of a veterinarian and implemented on the farm. Certified farms need to adhere to low levels of parasites, and the use of medicine before a disease is diagnosed (prophylactic use), is prohibited. Producers must manage farms in such a way that survival rate is high, and they need to have a farm specific mortalities reduction program that includes defined annual targets.

  • Social

ASC certification imposes strict requirements based on the core principles of the International Labour Organisation (ILO), these include among others prohibiting the use of child labour or any form of forced labour. All ASC certified farms are safe and equitable working environments where employees earn a decent wage and have regulated working hours. Farmers need to engage with local communities (including indigenous people), have a community stakeholder complaints process in place, and inform local communities about potential health and safety risks or changes in access to resources.

What we do

Standard documents

Date of publication
July 1, 2019

Flatfish - Standard documents

Confidental Infomation