Grey mullet

Mugil cephalus

Common Name(s)

English: Common mullet, Striped mullet, Common grey mullet, Flathead grey mullet, Flathead mullet ; French:, Muge Céphale, Muge à Groose Tête, Mugo Fangous, ; Spanish: Mugil Común, Mujol


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.


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



Cá Dối Mục

Simplified Chinese


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Date of Assessments

October 2020

Peer Reviewer

Agriculture Fisheries and Conservation Department

Assessment Organisation

RS Standards




  • Grey mullet (Mugil cephalus) is a catadromous species found across the world in coastal waters of tropical, subtropical, and temperate zones.
  • It has been farmed for centuries, traditionally in ponds for subsistence farming. Mugil cephalus is an important species in the Mediterranean region, Southeast Asia, Taiwan, Japan, and Hawaii.
  • FAO FishStat reports 13,681 tonnes of total aquaculture production of Mugil cephalus in 2016. Countries with reported volumes of grey mullet produced through aquaculture include: 2,244 tonnes in Taiwan, 1,900 tonnes in Israel, 700 tonnes (estimated) in Italy, and 198 tonnes in Greece (as of 2017).
  • Though official numbers are not reported, Egypt is the largest producer of cultured grey mullet, and it is also traditionally farmed in the Philippines, India, and Russia.
  • Aquaculture of grey mullet still depends on the collection of wild fry. Not only does this affect the sustainability of the farmed grey mullet industry, but it is also has a negative effect on the wild capture fishery.
  • Freshwater and brackish water ponds are the most common method of culture for grey mullet, which are often raised in polyculture with carp, tilapia, or milkfish. In these cases, the mullet will feed on leftovers and detritus from the other species, whereas in mullet monoculture the fish have been found to grow on chicken manure or rice or wheat bran to achieve proper growth rates (FAO, 2006-2020).
  • Most, if not all, of the farmed mullet is consumed in the producing countries where increasing demand exists. There is no known export market (FAO 2006-2020).
  • Depending on the part of the world, mullet is marketed fresh, dried, salted, and frozen; and roe sold fresh, dried, or smoked.

Pond culture, Grey Mullet

Grey mullet are grown in earthen ponds all over the world, and can be raised in fresh, brackish, or saltwater. Some farmers raise mullet in a polyculture system with complementary species such as carp, tilapia or milkfish, while others grow mullet as a single species or monoculture. The ponds used to culture grey mullet are first dug or ploughed, then left to dry by the sun, and finally given a layer of manure. The ponds are then filled with a shallow layer of water to establish natural feed (algae). When ready for stocking, the water level is increased and fingerlings are added. Some farmers will continue to add fertilizer throughout the growing cycle to aid productivity, and some will also supply feed beyond what is naturally occuring in the pond. Others prefer to grow mullet without any inputs to the ponds.

  • 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


No Known FIP


  • Grey mullet production in Hong Kong can be considered to be a medium risk.
  • In 2005, the Agriculture, Fisheries & Conservation Department implemented the Hong Kong Accredited Fish Farm Scheme (AFFS), a voluntary system of guidelines for aquaculture operations that wish to be deemed sustainable.
  • The farms are using some fishmeal in feed, though the quantity and source is unknown.
  • Most grey mullet farms in Hong Kong are part of the AFFS, which provides disease prevention and treatment guidelines.
  • Grey mullet farmers collect M. cephalus from inshore waters and estuaries, or purchase wild caught fry mainly from Mainland China, and some from Taiwan. There are very few farms that source fry from local Hong Kong waters.
  • Culture of grey mullet takes place in the northwestern region of Hong Kong’s New Territories. Fishponds in use in the area total 1,131 hectares, and in 2019 produced 2,278 tonnes of freshwater fish valued at $52 million.
  • The majority of these pond fish farms are engaged in polyculture, about 96%, producing carp in combination with tilapia or grey mullet. Some ponds are part of a larger nature reserve and act as wetlands, providing habitat for millions of migratory birds every year.
  • Grey mullet production in Taiwan can be considered to be a high risk.
  • Grey mullet culture in Taiwan still depends on the limited wild populations for collection of fry and juveniles.
  • Grey mullet juveniles are harvested primarily from the northwest and southwest coasts of Taiwan, and cultured to maturity in order to harvest the valuable roe.
  • The fish are raised in earthen ponds, either in a monoculture system with tens of thousands of juveniles, or a polyculture system with several thousand juveniles.