Farmed

Giant Grouper

Epinephelus lanceolatus

Common Name(s)

English: Brindle Bass, Brindled Grouper, Queensland Grouper

Insufficient Information

Insufficient information to assess risk

Medium

There is evidence that many of the potential environmental risks of the operation are managed at some level, however risks are not fully mitigated, and there is still room for improvement.

High

At least one of the environmental risk criteria has been scored high risk, and this is having a significant impact on the sustainability of the operation.

Traditional Chinese

花尾龍躉, 'Fa Mei Long Dun'

Simplified Chinese

鞍帶石斑魚

Japanese

Tamakai

Vietnamese

Cá Mú song

Malaysian

Kerapu pertang, kertang

Indonesian

Kerapu kertang

French

Mérou Lancéolé

Spanish

Mero Lanceolade

Date of Assessments

March 2020 (Peer review November 2021)

Peer Reviewer

Dr Mike Rimmer, University of the Sunshine Coast, Australia

Assessment Organisation

RS Standards

SEASONAL AVAILABILITY

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Overview

  • Giant Grouper (Epinephelus lanceolatus) is the largest bony fish found among coral reefs in the Indo-Pacific oceans, frequently growing over a meter long.
  • The vast majority of grouper aquaculture is carried out in Asia catering for the demand for live fish in restaurants. Unfortunately data from the FAO does not identify species level within the genus Epinephelus.
  • Giant grouper fetches the highest price of any grouper species on menus in Chinese restaurants.
  • Giant grouper in particular, compared with other grouper species, is a promising aquaculture species due to its fast growth rate. The main advantages are fast growth and resilience in culture because it is an estuarine species (and thus can handle changes in temperature and salinity better than the reef-dwelling groupers). On the other hand they are extremely difficult to breed and rear in captivity, compared to other Epinephelus species.
  • A variety of systems are employed in giant grouper aquaculture, including floating cages and ponds, inshore cages, and land-based tanks (known as recirculating aquaculture systems (RAS).
  • Seed for E. lanceolatus is largely hatchery-raised, with very limited amounts coming from wild capture sources.
  • Impacts of tropical fish cage farming on the environment are dependent on the types of ecosystem that the cage farming occurs in. For example, the nutrient inputs from cage farming in coastal estuarine and mangrove habitats may be insignificant compared to that from naturally occurring organic matter, and run-off from land-based activities such as pig farming.
  • Depending on the species and sophistication of the operation, grouper feed may consist of trash fish or pellet feed. Feed conversion ratios are very high for grouper fed on trash fish though can be made much lower for pellet feed that incorporate other protein sources in addition to marine ingredients..
  • As with the aquaculture production of other marine finfish species, Nervous necrosis virus (NNV) affects grouper at every stage of production, commonly infecting hatchery-reared juveniles, and has been responsible for major mortalities and economic losses.
  • Iridovirus and bacterial pathogens such as Vibrio species, Aeromonas, Streptococcus and parasites have also been found in farmed grouper (and farmed finfish generally).
  • There are no grouper producers found among aquaculture seafood certification ratings, namely Best Aquaculture Practices, Seafood Watch, and the Aquaculture Stewardship Council.
  • Giant Grouper (Epinephelus lanceolatus) is the largest bony fish found among coral reefs in the Indo-Pacific oceans, frequently growing over a meter long.
  • The vast majority of grouper aquaculture is carried out in Asia. Unfortunately data from the FAO does not identify species level within the genus Epinephelus.
  • A variety of systems are employed in grouper aquaculture, including floating cages and ponds, offshore circular cages, and land-based tanks. Giant grouper are typically reared in either offshore cages or land-based recirculating aquaculture systems (RAS), catering for the demand for live fish in restaurants.
  • Depending on the species and sophistication of the operation, grouper feed may consist of trash fish or pellet feed. Feed conversion ratios are very high (and unsustainable) for grouper fed on trash fish though can be made much lower for pellet feed used in RAS facilities.
  • Giant grouper in particular, compared with other grouper species, is a promising aquaculture species due to its fast growth rate and relatively low food conversion ratio. It also fetches the highest price of any grouper species on menus in Chinese restaurants (Yang, 2016).
  • There are no E.lanceolatus producers found among aquaculture seafood certification ratings, namely Best Aquaculture Practices, Seafood Watch, and the Aquaculture Stewardship Council.

Recirculating Aquaculture System

Recirculating aquaculture system (RAS) technology is a relatively new system but holds promise, particularly for raising finfish. The system is made up of land-based tanks with water filtering technology that enables the facility to operate in a closed loop. The only outputs are filtered water and waste, though some freshwater systems are able to collect fish/feed waste and use as fertilizer elsewhere, further improving the sustainability of this system. Due to its technology and energy requirements, RAS has high upfront costs, but is increasingly being implemented by new companies. Several producers in Asia are using RAS to grow giant grouper.

Earthen Ponds - giant grouper

Ponds are commonly used in many aquaculture operations across the world because they can be low-cost and easy to construct. Ponds for giant grouper culture are prepared and fertilized, then may receive adult tilapia to feed on the naturally occurring algae and to serve as live prey. The giant grouper fingerlings are added a month after the tilapia, and additional feeding commonly occur. Grading takes place periodically to reduce cannibalism, and the pond’s water quality is typically tested daily, with aerators used as needed.

Net pens / cages, marine fish

The design of the cage may be circular or square, and sophistication ranges from homemade floating bamboo cages to commercially produced cages with high quality materials. Broodstock are often held in land-based tanks alongside nursery operations. Once the nursery stage is complete, fingerlings are transferred to the net cages where they are grown to market size. Feeding is conducted daily, and size grading occurs once a month to reduce the risk of cannibalism. Net cages should be moved every 2-3 years to prevent negative impacts to the bottom habitat below. The floating cages are often homemade with locally available and inexpensive materials. Many marine fish species are commonly raised this way.

  • The Latin species name
  • Evidence of the country of origin, name and location of the farm
  • Evidence that the farm is compliant with national regulations
  • Evidence that production is controlled in a way that minimises impact on the wider marine environment (i.e. there is local planning, water quality testing etc.)
  • Evidence of where the seed originates
  • Evidence that the seed used on the farm has come from sustainable sources
  • Evidence of where the feed originates
  • Evidence that the feed used on the farm has come from sustainable sources
  • Evidence that the farm does not use any banned medicines / chemicals
  • Evidence that there is a plan / procedure in place to manage animal husbandry

FISHERIES IMPROVEMENT PROJECTS

No Known FIP

COUNTRY SPECIFIC RISK ASSESSMENTS

  • Giant Grouper production in China can be considered to be a high risk. There is limited information available to complete a full risk assessment.
  • Feed is a mix of trash fish and commercially produced pellets. Trash fish is an unsustainable source of feed as it relies on high amounts of wild caught species to produce smaller amounts of farmed species, and also contributes to increased pollution from the farm.
  • Commercially produced formulated feeds for grouper are now being used more widely in China, though the origin of ingredients in these feeds is unknown.
  • A recent study of grouper mariculture in Hainan province, China detected the dominance of fluroquinolones and tetracyclines (groups of antibiotic) in mariculture water, and also identified associated Antibiotic Resistant Genes in bacteria. This has wider implications for human health, and potential spread of opportunistic antibiotic resistant pathogens.
  • Historically, grouper aquaculture has been conducted in brackish water ponds or floating sea cages; however, land-based recirculating aquaculture systems (RAS) are being promoted for raising grouper, particularly Epinephelus lancelatus (see ATA profile for Hong Kong).
  • Giant Grouper production in Taiwan can be considered to be a high risk.
  • Whilst trash fish is still used in feeds, the fish protein can be largely replaced with other proteins, such as animal protein (abattoir waste) or processed plant proteins. For example, it has been shown that fishmeal could be 80% replaced with high-quality terrestrial protein meal for the culture of other grouper species such as coioides and hybrid species.
  • Disease represents a major obstacle for Taiwan’s grouper aquaculture industry. High stocking densities are still the norm and Nervous Necrosis Virus (NNV) affects grouper at every stage of production, commonly infecting hatchery-reared juveniles.
  • There is a risk of escapes from the farm, though the best available evidence suggests that it is unlikely that the cultured species will establish in the wild.
  • The operation does not rely on the collection of wild seed. Giant grouper artificial breeding was achieved in Taiwan in the 1990s and the island now has a successful hatchery industry, supplying larvae and juveniles to grow-out facilities and other countries in the region.
  • Giant Grouper production by Aquaculture Technologies Asia (ATA) in Hong Kong can be considered to be a medium risk.
  • Using its own recirculation aquaculture systems (RAS) technology, this large-scale, indoor farming facility is the first to be recognized as an accredited fish farm by the Agriculture, Fisheries, and Conservation Department of Hong Kong.
  • RAS production systems in general must be operated at high stocking densities because they have very high operating costs, and higher densities are generally associated with reduced fish welfare, in particular higher levels of stress indicators (such as corticosteroids) and potentially more common and more severe outbreaks of disease.
  • There is insufficient information to complete a full risk assessment.
  • There is one hatchery in Australia producing giant grouper (http://www.thecompanyone.com/). Some fingerlings are exported to Taiwan and Hong Kong SAR (to ATA); some are grown out in Australia.
  • For the fish grown out in Australia, some are grown in RAS systems, some are grown in a combination of RAS (nursery and over-wintering) and in ponds.
  • The fish sent to Taiwan enter the complex value chain of Taiwanese marine finfish production and so may pass through several different systems and operations before reaching market.
  • Note that the giant grouper fingerlings grown out in Australia are vaccinated against NNV prior to leaving the hatchery. Fingerlings for export are not vaccinated because there are currently no regulatory approvals in place in the recipient countries.