Grey Mullet Culture

Presented by- Jyoti SarojDepartment.- Fisheries Resource Management

College of Fisheries, Veraval

Introduction Mugil cephalus is commonly known as striped

mullet.

It is a euryhaline fish, cultured either alone or in combination with other fishes such as Tilapia/Milk fish/Pearl spot/Chinese carp.

History Grey mullet has been farmed for centuries in

extensive and semi-intensive ponds. Subsistence farming in ponds and enclosures has

been traditional in the Mediterranean region, South East Asia, Taiwan Province of China, Japan and Hawaii.

Since the early 1960s, flathead grey mullet has also been cultured in semi-intensive ponds with tilapia and carps in Egypt.

This species was first introduced to be cultured with carp in Israel in 1957.

Main Producer Countries• Italy• Israel• Egypt• Mexico• Peru• Hong kong• Singapore• Greece• Taiwan province of China

Habitat and Biology• Mugil cephalus is cosmopolitan in the coastal

waters. • It is found from Nova Scotia, Canada south to

Brazil, including the Gulf of Mexico and absent in the Bahamas and the Caribbean Sea.

• The flathead grey mullet is catadromous.• Flathead grey mullet is a diurnal feeder,

consuming mainly zooplankton, dead plant matter and detritus.

• Mullet have thick-walled gizzard-like segments in their stomach.

Mugil cephalus

Reproductive Biology The sexes are separate. Males are generally smaller and

slender whereas, in females belly shall be distended and swollen during spawning season.

In India Mugil cephalus breeds during the post monsoon period.

Absolute fecundity of Mugil cephalus in India is 13,20,000 and relative fecundity is 849 eggs/g body weight.

Collection of Fry

• Collected from river mouths, tidal streams, tidal creeks, swamps and tidal flats.

• In India, the fry of Mugil cephalus are restricted to the period from June to August.

• The early mullet fry are collected using dip nets, hapa nets and closed-meshed seines during high tides.

Hatchery Production

• Large numbers of sexually mature individuals are kept under optimum environmental conditions.

• Ripe fish are selected and placed in plastic or fibreglass tanks filled with seawater.

• Male:Female ratio 2–3:1 shortly before spawning.

• Females are injected by pituitary gonadotropin. Females spawn after 12 hours.

• Eggs are produced at a rate of 650–850/g body weight.

• Hatching takes place after 50-64 hrs .

Nursery Rearing After acclimatization, fry are stocked in earthen

nurseries at high densities, where they depend mainly on natural food.

Fry are kept in the nursery ponds for 4–6 months.

Stocking density 30,000/ha in nursery pond.

Rice or wheat bran is sometimes used as an additional source of food.

On growing Techniques• Grey mullet are usually culture in poly culture in

semi-intensive pond with common carp, grass carp, silver carp, tilapia and milk fish

• Intensive polyculture of mullets along with Chinese carps is carried out in Honkong.

• Mullet fingerlings stocked @ 10,000-15,000/ha and Chinese carp fingerlings stocked @ 1000-2000/ha

Rice or wheat bran added daily in amount of 0.5-1 % of biomass

Growing season is normally about 7-8 months. After 7-8 months mullet reach 75-1 kg.

Feed Supply

• Monoculture : Natural foods, grain mills and rice polishing plants.

• Polyculture: Extruded pellets are used in feed for Tilapia and Common carp

Harvesting Tecniques

Using gill nets.

Seine nets.

Total drain harvesting.

Harvesting of Grey Mullet Using Seine

Valli culture in Italy

• Modified estuaries are called Valli, produce primarily eels but mullet are the principal crop in the most advanced valli.

• Four Species are commonly stocked, according to the season, largest and most valued species is Mugil cephalus is found in the lagoon.

Valli including all the 300-500 ha structures in the venice area, located above the high tide line and connected with sea, from which brackish water pumped at high tide, creating an artificial tide.

The total annual yield of valli ranges from 90-200kg/ha of fish.

Mullet Culture In India• Mainly in West Bengal, Karnataka, Kerala and Goa.

• In monoculture stocking density is 6000no./ha production rate is 1189-1200kg/ha/year.

• Mullet is cultured with pearl spot and milk fish in south India

• Various species of shrimp often stocked in mullet.

• The net production in the grey mullet-milk fish combination ranged between 1600 and 2189 kg/ha/year.

Global Production of Grey Mullet

Egypt is the largest producer country in the mullet culture.

Sr. No.

Year Production in tones

1. 1997 25600

2. 2003 147000

Diseases and Problems Ergasilus lizae Caligus paget (Sea lice) Bacterial fin rot Saprolegnia infections

Large scale natural mortalities occur during nursery rearing.

Main Issues As aquaculture grey mullet depends largely on

collection of wild fry, it is affecting the resources for capture fisheries.

In countries where wild fry collection for aquaculture practiced, social problems usually result from the competition for resources between fish farmers and fisherman.

Conclusion• The grey mullet are polycultured with other

compatible species of fish and shrimps. • Production average 2.0-2.5 tonns/ha/year

during 8-9 months grow out periods.• Intensive farming is restricted due to non

availabilty hatchery seeds.• Highly production comes from traditional

culture system such as Valli culture in Italy.• Milk fish production is also very high in

combination with Mullet culture.

References• T.V.R. Pillay and M. N. Kutty, Aquacultre

Principles and Practices, Page No.(417-423)• Dr. P.C.Thomas, Dr. Suresh Ch. Rath, Dr.(Mrs)

Kanta Das Mohapatra, Breeding and Seed Production of Fin Fish and Shell Fish, Page No.(138-141)

• John E. Bardach, John H. Ryther, and William O. McLarney, Aquaculture the Farming and Husbandry of Freshwater and Marine Organisms, Page No.(285-300)

Thank you