THREAD-FIN BREAMSDemersal Fisheries Resources

Rahul MondalM.Sc.(I.F.)2nd SemesterS.I.F.CUSAT

GENERAL INTRODUCTIONThreadfin breams belongs to the family-Nemipteridae, order Perciformes. They are also known as Whiptail breams and False snappers.It’ constitutes an important demersal finfish resource in the Indian EEZ. They are found in tropical waters of the INDIAN and WESTERN PACIFIC WATER.The threadfin breams, also called pink perch… Kilimeen in Malayalam, Rani in Marathi, Madhumal meenu in Gujarati, Gulivindalu in Telugu..

Taxonomic Classification

Phylum- Chordata Subphylum- Vertebrata Class- Actinopterygii Order – Perciformes Family- Nemipteridae

There are about sixty species in five genera: Genus Nemipterus swainson(1839), Genus Parascolopsis boulenger

(1901), Genus Pentapodus gaimard(1824), Genus Scaevius whitley, Genus Scolopsis cuvier (1814)

Here in INDIA the most dominant sp. are N. japonicus & N. mesoprion distinctive characteristic

Caudal fin moderately forked, upper lobe slightly longer than lower and produced into a short or moderately long filament.

Three transverse scale rows on preopercle. Axillary scale present. A prominent red-suffused yellow blotch below origin of lateral line. Eleven to twelve pale golden-yellow stripes along body from behind

head to base of caudal fin. Pectoral fins very long, reaching to or just beyond level of origin of

anal fin.

Color: Upper body pinkish, silvery below.

Nemipterus japonicus

distinctive characteristic s<Nemipterus mesoprion>

•Lower edge of eye lies below a line drawn from tip of snout to upper base of pectoral fin. Dorsal fin origin about 4-7 scale rows from an imaginary line projected upwards from posterior edge of suborbital to dorsal profile. •Axillary scale present.

Color: Oblique golden yellow stripe from beneath eye to middle of maxilla. Upper body pinkish, silvery white below. This species closely resembles N. marginatus, but lacks the filamentous extension to the upper lobe of the caudal fin; the posterior margin of the suborbital is more or less straight, rather than evenly curved; and the upper stripe on the body is not divided anteriorly.

Nemipterus mesoprion

Species & Distribution

Six species are known from the seas around INDIA. They are Nemipterus japonicus (Japanese threadfin bream), N. mesoprion (Red-filament threadfin bream), N. delagoae(Delagoan threadfin bream) N.metopias ,N.nematophorus and N.tolu (Notched threadfin bream).Out of these the first two species only contribute to the bulk of the landings.

Threadfin bream is extensively found in tropical indo-pacific regions between 34°N - 11°S latitudes and 31°E - 133°W longitudes.

They mainly occur in muddy sandy bottom. Occur mostly in shallow water b/w 5 m -80 m depth(recorded upto 300 m depth). Nemipterus japonicas occur up to 40 m depth , N. mesoprion occur beyond 40 m depth.

Countries it occurs are- coastal waters of Eastern Africa north of Durban, Seychelles, Madagascar, Mauritius, countries bordering red sea and Persian gulf, Pakistan, India including Lakhshadweep Andaman & Nicobarislands, SriLanka, Myanmar, Vietnam, Malaysia, Thailand, Indonesia, Cambodia, NorthernAustralia, Polynesia, Micronesia,New guinea, China, Taiwan, Philippines and Hawaiian islands.

In INDIA more or less well defined peaks along WEST COAST (Gujarat, Maharashtra, Kerala)..

Geographical distribution of Threadfin bream

(www.aquamaps.org, version of Aug. 2010)

FOOD & FEEDING HABBIT

Most species are benthic(bottom feeding), carnivorous, eating small fishes, cephalopods, crustaceans and polychaetes; however, a few species eat plankton.

N. japonicus prefered to feed large number of crustacean like penaeid and non-penaeid shrimps.

N. japonicus are asynchronouscyclic feeder ie. there is no particular feeding time in a day for the population but individual fishes may follow a cyclic pattern of active feeding followed by cessation in feeding

N. japonicus are opportunistic feeders.

SIZE AT FIRST MATURITY&

WEIGHT

As we can see from length of the females are larger than the males.

Mature males commenced to appear at 140 mm length and the mature females dominated up to the 260-269 mm with gradual increase in the length of fish.

The length at first maturity is 14 c.m.

published weight: 596 g ; max. reported age: 8 years ; Source:( www.fishbase.org)

REPRODUCTION

Reproduction of Nemipterus japonicusMode - Dioecism

Fertilization – External

Description of life cycle and mating behavior Females predominate at larger sizes and males at smaller sizes, due to faster growth rate in males .

SEX RATIO

The females out numbered males in the commercial catches.

Percentage of males was low in most of the months except in March, May, September, November and December.

The sex ratio was different from the expected ratio 1:1 in almost all the months showing the predominance of females in the catches

SPAWNING

They are fractional spawners.Releasing ripe eggs in 2 spawning periodsSpawning seasons varies from locality to locality and among different sp.

Males dominated over females during Spawning

In the sea off Kerala, N.japonicus and N.mesoprion spawn during monsoon and postmonsoon periods with peaks during monsoon in the former and during postmonsoon in the latter species.

Sp. Name COAST MONTH

Japonicus N.W. COAST SEP-OCTS.E. COAST NOV-APR

Mesoprion NOV-MAR

N. Delagoae & tolu

S.E. COAST FEB-MARAUG-OCT

FECUNDITY

The annual fecundity (2 batches) ranges from 23,000 to 139,000 eggs

Fecundity of the fish increases with the increase in the length and weight of the fish while ova per gram of fish body weight has no relationship with the length of the fish.

FISH & FISHERY

Average Landing(‘000 tonnes)-Throughout the India

YEAR QUANTITY

1961- 1970 10.96

1971- 1980 29.53

1981- 1990 75.36

1991-2000 145.2

2001-2005 1841961-1970

1971-1980

1981-1990

1991-2000

2001-2005

020406080

100120140160180200

Avg. landing during 1961 - 2005

(India profile, CMFRI)

State wise landings in year 2000

Avg. landings tons

GUJARAT 45,642

KERALA 37,437

KARNATAKA 19,100

MAHARASTRA 9,273

TAMIL NADU 3,284

ANDHRA P. 1,201

WEST BENGAL 69 GUJRAT

KERALA

KARNATAKA

MAHARAST

RA

TAMIL

NADU

ANDHRA P.

WEST

BENGAL0

5,00010,00015,00020,00025,00030,00035,00040,00045,00050,000

*Status of exploited marine fishery resource

Avg. landing during 1961 - 2005

COASTAL ZONE

Tons(‘000)

NE 1.8

SE 20.4

SW 43.9

NW 33.91961-1970

1971-1980

1981-1990

1991-2000

2001-2005

0

50

100

150

200Avg. landing during 1961 - 2005

CRAFTS & GEARS

Basically Threadfin breams is a by-catch species. So, it is caught with other species….

The most popular fishing gears are gillnet, longline, lift-net, push net and traps.

In Kerala mainly- Bottom trawl net, Gill nets are used

MARKET

Marketed mainly fresh, but also frozen, steamed, dried-salted, dry-smoked, fermented or made into fish balls and fish meal.

MANAGEMENT

Fishing mortality rate of 2 major species are within reasonable permissible level, although cod end and mesh size of present trawl net can affect fish stock in long run.

Increase in cod end mesh sizes can input landing in long run.

Thread fin bream fishery contributed reasonably large catch in west coast and trawl ban in this region during SW monsoon will improve the stock

Use of non-selective gear in inshore water should be discouraged.

Cont. Monitoring of exploitation, stock assessment, biological assessment and sp composition should effectively practised for sustainability the stock

REFERENCES

Handbook Of Fisheries & Aquaculture, I.C.A.R.,p. 78

Joseph Mohan M. & Jayaprakash A.A., Status Of Exploited Marin Fishery Resources Of India, C.M.F.R.I, India, p. 153

MANOJKUMAR P.P., Some aspects on the biology of Nemipterus japonicus (Bloch) from Veraval in Gujarat, Calicut Research Centre of Central Marine Fisheries Research Institute,Calicut, India

MADAN MOHAN* AND A. K. VELAYUDHAN,SPAWNING BIOLOGY OF NEMIPTERUS DELAGOAE (SMITH) AT VIZfflNJAMC.M.F.R.I, Cochin - 682031

SRIRAMACHANDRA MURTY, K . V. SOMASEKHARAN NAIR, P. A. THOMAS, S. LAZARUS, S. K. CHAKRABORTY,S. G. RAJE, C. GOPAL, P . U. ZACHARIA AND A. K. VELAYUDHAN,PRESENT STATUS OF EXPLOITATION OF FISH AND SHELLFISH RESOURCES : THREADFIN BREAMS,C.M.F.R.I, Cochin – 682031

www.fishbase.org

www.fao.org

www.wikipedia.org

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