Giant Grouper risk assessment
November 2020 1
GIANT GROUPER – Epinephelus lanceolatus
The Giant grouper is the largest bony fish found among coral reefs in the Indo-Pacific oceans,
frequently growing over a meter long. It belongs to the genus Epinephelus, of which there are 89
grouper species, and is also known as the King grouper or Kertang grouper. Commercial
aquaculture of grouper species began in the 1970s and depended on collection of wild fry. By the
1980s, however, artificial spawning and hatchery technology was achieved for two species
(Orange-spotted grouper [Epinephelus coioides] and Malabar grouper [E. malabaricus]), and E.
lanceolatus followed in 1995. There are now about a dozen species of grouper for which the
aquaculture cycle has been closed.
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, and so the following numbers
correspond to aquaculture of all groupers in that genus. It is reported that 36 Epinephelus species
have been trialed or are currently in production in aquaculture. China, Taiwan, and Indonesia are
responsible for 95% of the world’s farm raised [Epinephelus] grouper.
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). Depending on the species and
sophistication of the operation, grouper feed may consist of trash fish or pellet feed. A feed
conversion ratio (FCR) of 1.4:1
1
has been reported for giant grouper aquaculture in RAS facilities,
though this system is not the norm. Seed for E. lanceolatus is largely hatchery-raised, with some
wild capture.
Grouper farming caters to the Chinese demand for live fish in restaurants. 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.
1
A 1.4:1 feed conversion ratio means that 1.4kg of feed is required to produce 1kg of giant grouper. This is
considered to be a favourable conversion ratio for this particular species.
Giant Grouper risk assessment
November 2020 2
China
China is the world’s largest producer of farm-raised groupers, by volume. Aquaculture in
China is currently undergoing a transformation toward more sustainable practices, and that
includes grouper aquaculture. Historically, grouper aquaculture has been conducted in brackish
water ponds or floating sea cages; however, land-based recirculating aquaculture systems (RAS)
are being promoted as the newest and most sustainable technology for raising grouper, particularly
Epinephelus lancelatus.
Risk Assessment
• Farm Siting: Medium Risk
o Planning laws exist but not fully enforced/only partially effective
• Nutrient Pollution:
o There is too limited information available to assess this criterion.
• Feed Source: High Risk
o The source of feed is undocumented or shown to come from an unsustainable
fishery.
o Feed is a mix of trash fish and commercially produced pellets
o 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
▪ Also contributes to decreased environmental quality of farm
• Disease, medicine, and chemicals: Medium risk
o Disease is a common problem in grouper aquaculture, though there is limited
information for China
• Introductions/Genetics: Medium Risk
o 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.
o Some culture is in marine net pens which poses the threat of escape; land-based
farms do not pose a threat.
• Wild Seed: Medium Risk
o Some seed likely to come from second-generation broodstock in closed loop
hatchery production.
o China imports much of its grouper seed from Taiwan.
o Collection of wild seed still takes place.
• Fish Welfare: not assessed
o There is too limited information available to assess this criterion.
Taiwan
Grouper aquaculture in Taiwan is well advanced and production of the giant grouper
(Epinephelus lanceolatus) is considered a specialty of the island nation, as well as its most valuable
cultured species. Farmers began raising groupers in 1975 in the Penghu islands by ranching wild
caught juveniles in ponds or pens until they reached market size (van Beijnen & Yan, 2018).
Closed loop aquaculture was achieved for two grouper species in the 1980s, and hatchery
technology for Epinephelus lanceolatus was achieved in Taiwan in 1995; fingerling production
began two years later. Much grouper aquaculture takes place in brackish water ponds on land,
Giant Grouper risk assessment
November 2020 3
though offshore cage culture began to be developed in the 1990s, primarily for cobia, and has now
become a means for raising giant grouper (Chen & Hsu, 2006).
Grouper farming is highly specialized in Taiwan, with each step of the process separated:
one farm produces eggs from captive broodstock, another supplies hatched larvae, a nursery
provides fingerlings, and grow-out facilities purchase the juveniles once they reach an appropriate
size for pond or cage culture (Yang, 2017). Taiwan’s mild climate allows for raising grouper year-
round, which is not possible in mainland China.
Risk Assessment
• Farm Siting: Low Risk
o Effective planning laws in place that ensure farms have been situated in a way that
minimizes impact on the local environment, also considering siting in relation to
other farms.
o Grouper aquaculture in Taiwan mainly takes place in land-based tanks and ponds,
however the industry is expanding to marine sea cages.
o In 1993, the government established exclusive fishery zones for marine cage culture
(Chen & Tsu, 2006).
o Taiwan’s Fisheries Act includes aquaculture in Chapter 2, Article 15 as a type of
“Fishing Right” fishery, identified as either:
▪ “Demarcated fishing right: the right to partition a specific water area for
operating aquaculture
▪ “Exclusive fishing right: the right to use a specific water area to form a
fishing ground for fisheries access privilege holders to operate
[aquaculture]” (Fisheries Act, 2019).
▪ Operators (individuals or fisherman association) may register for exclusive
fishing rights; once approved the association or cooperative is responsible
for drafting rules on fishery access and submit to authority for approval
o “The regulations for registration and management of inland aquaculture shall be
prescribed by the municipal/county/city competent authority…Any aquatic
organisms that involved in genetic breeding and transference shall run prior field
tests and safety assessments before promotion and utilization.” Article 69, Chapter
8, Fisheries Act, 2019).
• Nutrient Pollution – Medium Risk
o There is some monitoring of water quality and feed use, though not to any
prescribed standard; monitoring records are incomplete.
o Groupers are raised in high-density culture systems which can lead to an excess of
nutrients.
▪ “high concentrations of nitrogen and carbon discharged from cage
aquaculture are a potential threat to the environment in the vicinity of cage
farms.” (p.142, Chen & Hsu, 2006).
o As Taiwan’s grouper industry continues to improve, more technology is being
adapted for monitoring water quality and environmental conditions
▪ For instance, one giant grouper pond has installed devices that continually
monitor water quality in real time and notify the farmer of any adverse
changes via smartphone; this method is much more efficient than the
traditional reliance on the naked eye (Lin & Tseng, 2019).
Giant Grouper risk assessment
November 2020 4
• Feed Source: High Risk
o The source of feed is undocumented or shown to come from an unsustainable
fishery.
o Groupers are carnivorous and require high inputs of fish protein; trash fish is still
the most common type of feed used in grouper aquaculture in Taiwan
▪ This source is unsustainable as it utilizes large amounts of marine protein
for a smaller output, and pollutes the culture environment
o A commercial pellet feed has been developed but is not widely used; the pellets do
not have a significantly more efficient feed conversion ratio (FCR) over trash fish,
but are better for the cultured environment
▪ Over-feeding can lead to a degraded environment and thereby disease
• Disease, medicine, and chemicals: Medium Risk
o The farm can evidence that medicines and chemicals are legal, though records
incomplete.
o Disease represents a major obstacle for Taiwan’s grouper aquaculture industry
▪ High stocking densities are still the norm
▪ 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 (Yang, 2016).
▪ “Grouper have been found to be infected by NNV, Irido virus and bacterial
pathogens such as Vibrio species, Aeromonas, Streptococcus and
parasites.” (Yang, Lin & Lin, 2014).
o Antibiotics are used but this can create resistant bacteria
o An oral NNV vaccine has recently been developed and virus-free hatchery concept
proven (Yang, 2016), a promising advancement for the industry
• Introductions/Genetics: Medium Risk
o 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.
o Floating sea cages pose a risk for escapes, however, pond farming does not.
o Taiwan’s grouper industry primarily utilizes land-based tanks for hatchery
operations and land-based ponds for grow-out, limiting the chance of escapes.
▪ Marine sea cages are expanding only recently
• Wild Seed: Low Risk
o The operation does not rely on the collection of wild seed.
o 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.
o There are reports that some collection of wild seed still takes place, but Taiwan has
the most advanced hatchery technology for grouper, including E. lanceolatus
• Fish Welfare: Medium Risk
o Aspects of animal husbandry not properly controlled (e.g. stocking densities not
recorded/managed, no veterinary care).
o High stocking density in conjunction with trash fish as feed lead to poor
environmental quality and disease.
o Fish are sold and transported live.
Giant Grouper risk assessment
November 2020 5
Hong Kong – Aquaculture Technologies Asia (ATA)
Established in 2003, Aquaculture Technologies Asia (ATA), based in the New Territories,
is Hong Kong’s premier supplier of full-cycle farmed giant grouper. 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, a voluntary system of guidelines for aquaculture operations that wish to be deemed
sustainable. ATA is now supplying giant groupers at an average size of 1 – 9 kilograms to a number
of high-end hotels and restaurants, wholesaling between USD30 - 40 per kilo, and may retail up
to twice this amount.
Risk Assessment
• Farm Siting: Low Risk
o ATA uses Recirculation Aquaculture System (RAS) technology, and production
is in indoor tanks.
• Nutrient Pollution:
o RAS is a closed system, and waste water will enter sewage systems.
• Feed Source:
o The groupers are fed with high quality feed free of heavy metal and other
pollutants that are commonly found in the food chain of coastal sea fish.
• Disease, medicine, and chemicals: Low Risk
o Through the exclusive use of tap water and aquarium salt, they recreate an
environment where the habitat of giant groupers can be monitored and controlled
for safety and quality.
• Introductions/Genetics: Low Risk
o Production is solely from RAS indoor tanks.
• Wild Seed: Low Risk
o ATA brings in giant groupers as fingerlings from a hatchery. These are then
nurtured for a period of 12 to 18 months until they reach market size.
• Fish Welfare:
o Awaiting information
Indonesia
Grouper aquaculture production in Indonesia is a relatively new industry, with significant
advancements made in the last 20 years. Ever-increasing demand from China for live groupers,
alongside declining wild populations, has driven development in farming techniques, with support
from the Indonesian government in expanding the industry. While information specific to
production of Epinephelus lanceolatus is limited, the species is one of several main grouper species
raised in Indonesia (FAO, 2006-2020).
Grouper farming is scattered across the country and expanding, much of it taking place in
the southwest region of Sumatra and some in the northeast Maluku-Papua. Production is growing
in the Lampung area of southern Sumatra, and cage culture can be found throughout the islands
Sumatra, Bangka, Bangkulu, Lampung, Kepulauan, Seribu, Banten, Java, Lombok, Kalimantan
and Sulawesi (De Silva and Phillips, 2007). There is one area in particular, located in the Situbondo
Giant Grouper risk assessment
November 2020 6
region of East Java, known as the City of Groupers. “There are approximately one hundred
household scale hatcheries in Situbondo that produce grouper seeds…with an average of about 50
million eggs monthly,” (AQUATEC, 2019) which are spread to buyers across Indonesia and even
exported to other countries. In Situbondo, a fast-growing hybrid species is being developed
between the giant grouper and the brown-marbled grouper, known as Cantang grouper. Another
hybrid between the brown-marled grouper and the camouflage grouper is also raised, known as
the Cantik grouper, and prized for its fast growth rate and resistance to disease (AQUATEC, 2019).
The most commonly raised grouper species in Indonesia include Humpback Grouper (Cromileptes
altivelis) and Brown-Marbled Grouper, also known as Tiger Grouper (Epinephelus fuscogutattus).
Indonesia is a major producer of grouper seed stock, though a portion of the country’s
aquaculture production still depends on wild-caught seed. A breakthrough in grouper hatchery
technology was achieved in 1998 by the Gondol Research Institute for Mariculture (GRIM), and
grouper seed has been successfully produced on a commercial scale since. The technology has
“been adopted by farmers in the northern part of Bali, East Java (Situbondo) and South Sumatra
(Lampung).” (Section 3, Sugama, 2010).
Repeatedly identified as the most limiting factor to Indonesia’s grouper aquaculture
industry is the feed. Trash fish is most commonly used to rear grouper, but is an unsustainable
source of protein that also has a negative impact on environmental quality and contributes to the
spread of disease. Unfortunately a commercial pellet feed is much more expensive than trash fish
and without proven growth benefits (Rimmer et al. 2016). Despite its progress, there remains much
room for development and improved sustainability in Indonesia’s grouper aquaculture industry.
Risk Assessment
• Farm Siting: Medium Risk
o Planning laws in place, although these do not completely mitigate all risks
concerned with farm siting/only partially effective.
o Indonesia’s grouper farms are largely located in marine estuaries or sheltered
coastal waters, and reared using marine cage culture.
o Aquaculture is defined in Indonesia’s Fisheries Law, which describes fish
cultivation and fish breeding as a fisheries management tool.
o “Provincial Governors are in charge of identifying marine or coastal areas for the
development of mariculture, in the territories under their jurisdiction.” (FAO, 2006-
2020).
o “The 2004 Fisheries Law requires a specific license called SIUP to engage in
fishery business, including aquaculture. However, small fishermen and small fish
breeders are exempt from such requirement.” (FAO, 2006-2020).
o An SIUP for aquaculture is issued by the Provincial Governor or Head of
Municipality; companies must provide the following information to apply: business
plan, tax number, company charter, vessel documents, aquaculture site location,
environmental impact statement (FAO, 2006-2020).
▪ “An EIA is required for the cultivation of shrimp/fish-breeding ponds, with
or without a processing unit, exceeding 50 ha in size.” (FAO)
▪ Note while there are a handful of larger operations in Indonesia, most
grouper farms are small-scale and would not meet the 50ha requirement.
• Nutrient Pollution: Medium Risk
Giant Grouper risk assessment
November 2020 7
o There is some monitoring of water quality and feed use, though not to any
prescribed standard. Monitoring records are incomplete.
o Hatcheries measure water quality and feed, among other environmental factors, in
order to increase the rate of survival.
o However, some grouper farms (grow-out operations, using sea cages) may be
considered high risk as there is no measurement or regulation of feed and water
quality management.
o Trash fish is still a source of feed, contributing to nutrient pollution as fish are
simply fed to satiation as indicated by slowed activity (Rimmer et al. 2016).
• Feed Source: High Risk
o The source of feed is undocumented or shown to come from an unsustainable
fishery.
o Groupers are carnivorous and prefer high inputs of fish protein; a generic
commercial pellet feed is available but trash fish is still commonly used
o Trash fish is more cost effective for raising groupers and many farmers believe it
produces a higher quality product
▪ Trash fish was found to be more cost effective for growing grouper at a food
conversion ratio (FCR) up to 13:1
2
(Rimmer et al. 2016).
▪ However, trash fish is unsustainable as it uses large quantities of marine life
not commercially valuable to produce much smaller quantities of the
cultured species.
• Disease, medicine, and chemicals: Medium Risk
o The farm can evidence that medicines and chemicals are legal, though records
incomplete.
o Disease is a common risk in Indonesian grouper aquaculture due to high density
and use of trash fish as feed, both of which lower environmental quality and
increase opportunity for transfer.
o No hormones used in hatchery production of Situbondo region, which supplies
millions of fry (AQUATEC, 2019).
▪ However, Khumaida et al. found the cause of a recent mass mortality here
to be viral nervous necrosis (VNN), affecting hybrid grouper species.
o “The 2004 Fisheries Law provides that the use of chemical or biological substances
which may harm aquatic resources or the environment is forbidden in both fisheries
and aquaculture. Further, the Law prohibits the use of additives that may endanger
human health.” (FAO, 2006-2020).
▪ However, “No specific provisions are made with regard to the use of drugs
in aquaculture.” (FAO).
• Introductions/Genetics: Medium Risk
o 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.
o While wild seed is still used to some degree and Epinephelus lanceolatus is native
to the region, the use of hatchery seed leads to genetics that are different from the
wild populations.
2
This means that 13kg of trash fish is required to produce 1kg of farmed fish.
Giant Grouper risk assessment
November 2020 8
o There is evidence that farmed grouper have low genetic diversity, as described by
Hassan et al. (2015) regarding tiger grouper samples from small-scale Malaysian
hatcheries, which can lead to lowered disease resistance and deformities.
o Because grouper aquaculture is carried out in floating sea cages, there is a risk that
farmed individuals may escape, possibly mixing the altered genetics of cultured
fish with the wild populations.
▪ The effects of escaped farmed grouper on wild populations is not well
understood; hybrid groupers represent the highest risk as their genetics may
allow escaped individuals to outcompete native species.
• Wild Seed: Medium Risk
o Some seed comes from second-generation broodstock in closed loop hatchery
production.
o Indonesia’s grouper aquaculture is in transition: historically seed was wild caught
but is increasingly coming from hatchery operations. “Almost 75% of the seed
needed for aquaculture comes from hatcheries.” (Sugama, 2010).
o There are several government and private hatcheries, and hundreds of backyard
hatcheries are spread across the country
▪ These smaller operations supply to small-scale farmers; they produce
mainly tiger grouper (Epinephelus fuscoguttatus) and some humpback
grouper (Cromileptes altivelis) (PEMSEA, 2017).
▪ Several hybrid species have also been developed (mostly prominently the
cross between male giant grouper Epinephelus lanceolatus and female tiger
grouper Epinephelus fuscoguttatus), and seed produced in Indonesia is
distributed nationally as well as internationally.
• Fish Welfare: Medium Risk
o Aspects of animal husbandry not properly controlled (e.g. stocking densities not
recorded/managed, no veterinary care).
o At the hatchery stage groupers and their environment are closely monitored to
increase survival, however, high mortality rates persist.
o In the grow-out stage, fish are monitored but high stocking densities are common,
which leads to poor environmental quality and disease.
o Fish are sold live; grouper are worth more alive
Giant Grouper risk assessment
November 2020 9
References
AQUATEC. 2019, March 21. BPBAP Situbondo, Home of Hybrid Grouper. Retrieved from
http://aquatecindonesia.com/bpbap-situbondo-home-of-hybrid-grouper/
ATA. 2016. https://slowfood.com.hk/tag/aquaculture-technologies-asia/
Chen, Y.S., and Hsu, C.Y. 2006. Ecological Considerations of Cage Aquaculture in Taiwan. J.
Fish. Soc. Taiwan, 33(2): 139-146. Retrieved from:
https://www.academia.edu/4901615/The_Ecosystem_Approach_for_Cage_Culture_in_T
aiwan_Ecological_Considerations_of_Cage_Aquaculture_in_Taiwan
De Silva, S.S. and Phillips, M.J. 2007. A review of cage aquaculture: Asia (excluding China). In
M. Halwart, D. Soto and J.R. Arthur (eds). Cage aquaculture – Regional reviews and
global overview, pp. 18–48. FAO Fisheries Technical Paper. No. 498. Rome, FAO. 241
pp. Retrieved from: http://www.fao.org/3/a1290e/a1290e02.pdf
FAO 2006-2020. National Aquaculture Sector Overview. Indonesia. National Aquaculture
Sector Overview Fact Sheets. Text by Sri Paryanti, T. In: FAO Fisheries and Aquaculture
Department [online]. Rome. Updated 9 February 2006.
Fisheries Act. 2019. Fisheries Agency, Council of Agriculture, (Taiwan ROC). Retrieved from
https://www.fa.gov.tw/en/LegalsActs/content.aspx?id=1&chk=f8ca5d8c-49db-46b5-
9839-43d955e36275¶m=pn%3d1
Froese, R. and D. Pauly. Editors. 2019. Epinephelus lanceolatus. FishBase. www.fishbase.org.
Hassan, N. C., Aziz, A.H.A., Ali, N.M., Ariffin, N.A., Chu, I.K.C., Mustafa, S., and Sheriff, S.
M. 2015. Genetic Diversity in Farmed Tiger Grouper Broodstock Inferred by Partial
Cytochrome b Gene. International Journal of Chemical, Environmental and Biological
Sciences, Vol. 3, Issue 1. Retrieved from:
https://www.researchgate.net/publication/291756467_Genetic_Diversity_in_Farmed_Tig
er_Grouper_Broodstock_Inferred_by_Partial_Cytochrome_b_Gene
Khumaidi, A., Fadjar, M., Iranawati, F., Kilawati, Y., & Yanuhar, U. (2019). Mass mortality
associated with viral nervous necrosis of hybrid grouper (Epinephelus sp.) cultured in
city of grouper. International Conference On Biology And Applied Science (Icobas). doi:
10.1063/1.5115724
Lin, T. C., & Tseng, S. (2019, October 10). Smart Monitoring Modernizes Aquaculture Pond
Management. Retrieved from https://english.cw.com.tw/article/article.action?id=2563
Phillips M, Henriksson PJG, Tran N, Chan CY, Mohan CV, Rodriguez U-P, Suri S, Hall S and
Koeshendrajana S. 2015. Exploring Indonesian aquaculture futures. Penang, Malaysia:
WorldFish. Program Report: 2015-39.
Giant Grouper risk assessment
November 2020 10
Rimmer, M.A., Wajan, S., Indradjaja, D.D., Adiasmara Giri, N., Laining, A. 2016. Compound
feeds for grouper aquaculture – why has adoption been so poor? Aqua Culture Asia
Pacific Magazine. Vol. 12, No. 5.
https://www.researchgate.net/publication/311761708_Compound_feeds_for_grouper_aqu
aculture-why_has_the_adoption_been_so_poor
Sugama, K. 2010. Public Policy for Sustainable Development of Grouper Aquaculture in Indonesia.
Directorate of Seed Development Directorate General of Aquaculture Indonesia.
https://www.crawfordfund.org/wp-content/uploads/2014/03/sugama-
aquacultureiIndonesia.pdf
van Beijnen, J., & Yan, G. (2018, November 20). Super grouper: advances in RAS production in
Asia. The Fish Site. Retrieved from https://thefishsite.com/articles/super-grouper-
advances-in-asian-aquaculture
Yang, H.-L., Lin, H.-Y., & Lin, C.-C. (2014, January 3). The search for sustainable grouper
farming. Global Aquaculture Advocate, Global Aquaculture Alliance. Retrieved from
https://www.aquaculturealliance.org/advocate/search-for-sustainable-grouper-farming/
Yang, H.-L. (2017, March 28). Grouper farming: current bottleneck and new technology. The
Aquaculturists. Retrieved from http://theaquaculturists.blogspot.com/2017/03/28032017-
grouper-farming-current.html