Haliotis discus hannai; Haliotis tuberculata

Method of production — Farmed
Production country — Ireland
Production method — Recirculating system
Picture of Abalone

Sustainability rating one info

Sustainability overview

Updated: November 2019.

Abalone farmed in Ireland in a recirculating aquaculture system (RAS) have little environmental impact and do not require any commercial feed sources as they are fed an algal-only diet. As the system is completely closed, it avoids impacting on sensitive habitats and has no depletion of freshwater supplies. A lack of pathogens and parasites means that there is no chemical usage and no impact from this on wild populations. There is also no risk escapes and no measures needed to deter predators. Environmental regulations and management are either not applicable or are fully effective, making abalone farmed in Ireland a sustainable seafood choice.

Feed Resources

Criterion Score: 5 info

Abalone do not require any commercial feed sources as they are fed locally-harvested seaweed only. The seaweed branches are cut by hand or collected from the shore after being washed up. No fish meal of fish oil is used and no palm oil or soy is used. Therefore, it gains the highest score in the feed section of the assessment.

Environmental Impacts

Criterion Score: 8 info

Abalone farmed in Ireland in a recirculating aquaculture system (RAS) have little environmental impact. They are built and operated on land and may utilize previously existing buildings, thereby avoiding sensitive habitats. When purpose-built, this is done on previously converted land and therefore there is no loss of habitat or loss of ecosystem functionality. As the system is completely closed, there is also no depletion of freshwater supplies as water is only used to top up due to evaporation.

Pathogens and parasites can also be a problem in RAS systems, however, this is not known to be a problem in abalone aquaculture in Ireland and any disease outbreaks would not impact on wild populations. A lack of pathogens or parasites also reduces the need for chemicals and no chemicals are used in this system.

As the system is closed, any wastewater leaving the facility has the ability to be treated and sterilised prior to discharge. Juveniles are hatchery-based and there is also no risk of escapes and no measures are needed to control predators. Therefore, Abalone farmed in RAS systems scores highly for environmental impacts and interactions.

Fish Health and Welfare

Criterion Score: 1 info

Animal welfare is not applicable for shellfish as it is not covered by EU regulations on welfare. Humane slaughter has been carried out by RSPCA definitions.


Criterion Score: 3 info

As this assessment is for land based production, the regulations regarding the environmental impacts of aquaculture are either not applicable or are in place and are fully effective. Land based recirculation systems are not subject to terrestrial planning, including farm level Environmental Impact Assessment (EIA). The producers of Abalone in recirculating systems in Ireland are not producing to independently audited, 3rd party certification standards.

Production method

Recirculating system

Abalone can be farmed on land in aquaculture systems that are enclosed, referred to as “recirculating systems”, which means that all water and waste are contained. Abalone graze on seaweeds for food.


Abalone (called ormer in France and elsewhere) are molluscs, belonging to a group of animals known as gastropods (the same group as whelks). Abalone have one shell which is flattened, its shape gave their genus the name of Haliotis which means “sea ear”. They have a worldwide distribution, along the coastal waters of every continent, except the Atlantic coast of South America, the Caribbean, and the East Coast of the United States. Abalones reach sexual maturity at a small size, and fertility is high and increases exponentially with size. The spawning season varies among species ; for e.g.. Red abalone in some locations spawn throughout the year. Sexes are separate and fertilization is external, both the eggs and sperm are broadcast into the water . A 1.5 inch abalone may spawn 10,000 eggs or more at a time, while an 8 inch abalone may spawn 11 million or more eggs. The fertilized eggs hatch into floating larvae that feed on plankton until their shells begin to form. Once the shell forms, the juvenile abalone sinks to the bottom where it clings to rocks and crevices with its single powerful foot. Settling rates appear to be variable. After settling, abalones change their diet and feed on macroalgae. Abalone feed on algae in the wild and on some farms, although a manufactured feed is also used. In the wild abalone numbers have declined for a number of reasons, the most serious being illegal harvesting.


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European Commission. 2012. Guidance on Aquaculture and Natura 2000. Available at https://ec.europa.eu/fisheries/sites/fisheries/files/docs/body/guidance-aquaculture-natura2000.pdf [Accessed on 08.08.2019].

FAO Globefish. 2017. World abalone production at high levels, yet prices remain steady. Available at http://www.fao.org/in-action/globefish/market-reports/resource-detail/en/c/902588/ [Accessed on 04.11.2019].

Hannon, C., Officer, R. A. and Le Dorven, J., 2013. Review of the technical challenges facing aquaculture of the European abalone Haliotis tuberculata in Ireland. Aquacult Int, 21, pp. 243-254. Available at https://link.springer.com/article/10.1007/s10499-012-9584-7 [Accessed on 08.08.2019].

Connemara Abalone. 2009. Abalone Farming - in the West of Ireland. Available at http://www.abalone.ie/abalone-farming.html [Accessed on 08.10.2019].

Monterey Bay Aquarium Seafood Watch. 2017. Abalone. Available at https://www.seafoodwatch.org/-/m/sfw/pdf/reports/a/mba_seafoodwatch_abalonefarmedreport.pdf [Accessed on 08.10.2019].

Monterey Bay Aquarium Seafood Watch. 2014. Recirculating Aquaculture Systems (RAS) - Global, All Species. Available at https://www.seafoodwatch.org/-/m/sfw/pdf/reports/g/mba_seafoodwatch_global_ras_report.pdf [Accessed on 11.11.2019].