fishery and population dynamics of little tuna(euthnnus affinis ) land

SYNOPSIS OF P.G. RESEARCH PROBLEM OFFishery and Population Dynamics Of Little Tuna (Euthynnus affinis) landed at Veraval coast.”UNDER THE GUIDANCE OFDr. A.Y. DESAIProfessor and HeadDEPARTMENT OF FISH ERY BIOLOGYCOLLEGE OF FISHERIESJUNAGADH AGRICULTURALUNIVERSITYVERAVAL : 

SYNOPSIS OF P.G. RESEARCH PROBLEM OFFishery and Population Dynamics Of Little Tuna (Euthynnus affinis) landed at Veraval coast.”UNDER THE GUIDANCE OFDr. A.Y. DESAIProfessor and HeadDEPARTMENT OF FISH ERY BIOLOGYCOLLEGE OF FISHERIESJUNAGADH AGRICULTURALUNIVERSITYVERAVAL Submitted by Name: KAWKABUL-SABHA Registration No. : J4-00439-2009 Degree for: M. F. Sc. (FISHERIES RESOURCE MANAGEMENT)

Title of Research problem: : 

Title of Research problem: “Fisheries and Population Dynamics of Little Tuna (Euthynnus affinis) Landed on Veraval coast.”

. INTRODUCTION : 

. INTRODUCTION Tuna contributes 1.9% of the Total Marine fish production out of 52% Pelagics of India. Euthynnus affinis constitutes Major among Gujarat Tuna. Landing of E. affinis in Gujarat is estimated as 0.65% in Gujarat and in veraval its about 17.5%. Caught in Saurashtra from Sept-May, peak Oct-Dec. Caught through gillnet of mesh size 110-115mm & 160-165mm by Jada jal by FRP Dugout canoes 30-50m depth. Very little work on Growth & stock assessment in Gujarat has been done.

Practical Utility : 

Practical Utility E.affinis forms 58% of the Total Tuna landings amounting to 32.41tonnes. Important component of drift gill net fishery in Gujarat. Season- wise body components which varies also due to Maturity and as this fish contributes to raw material of Sashimi and Canning based products studies on its Growth, Mortality & Stock Assessment assumes high importance. Therefore devising a strategy for managing this fishery resource at a sustainable level assumes importance

Objectives : 

Objectives BIOLOGY  To find out the sex ratio, maturity, batch fecundity, ova diameter, food and feeding habit. To find out the spawning season, gonad somatic index(GSI) POPULATION DYANAMICS  To find out the von –bertalanffy growth parameter asymptotic length (L∞) and Growth coefficient (k). To find out length-weight relationship and age at zero length(t0). To find out Fishing mortality (F), Natural mortality (M), Total mortality(Z). To find out exploitation ratio(E).

Review of literature : 

Review of literature Gopakumar et al. (1989) Studied fishery and exploitation status of Euthynnus affinis from cochin. Dayaratne, P., and De Silva, J. (2001) Studied the stock assessment of (E.affinis) using two set of parameters growth coefficient (K) and asymptotic length L) from west coast off Sri Lanka. .Andrade H.A., Campos R.O. (2002) Investigated on the Allometry coefficient variations of the length-weight relationship of skip jack tuna (katsuwonus pelamis) from the south west south Atlantic waters.

Continue… : 

Continue… Madhu et al.(2002) have studied on the fishery and exploitation status of coastal tunas from lakshadweep,Andaman and Nicobar islands. Darvishi,M., et al.(2003) Studied population dynamics of E affinis off the Hormuzgan province waters (Persian gulf and Oman sea). Parameters like Natural mortality, fishing mortality and total mortality were obtained from Hormuzgan waters  Lessa and Duarto-neto(2004) Worked on age and growth of yellow fin tuna(Thynnus albacores) they used parameters such as von bertalanffy growth, asymptotic length L, growth coefficient K, and age at zero length to from western equatorial Atlantic waters.

Continue… : 

Continue… Khan (2004) Studied age, growth, mortality and stock assessment of E. affinis the growth parameters estimated for the E. affinis were total mortality coefficient (Z), natural mortality(M),size range, asymptotic length(L) and growth coefficient (K). Wann-deu chiou et al.(2004) Studied the Reproduction ,Food and Feeding habits of Euthynnus affinis in Taiwan Abdusammad et al.(2005) Studied fishery and population exploitation of coastal tunas from Tuticorin Ghosh S. et al. (2006) Studied on the fishery and population characteristics and yield estimates of coastal tunas and they investigated the parameters such as yield /recruit, stock mortality exploitation and, MSY, length weight relation ship, and growth off Veraval coast.

Continue……. : 

Continue……. Sujata, Deepti (2006) and Kasim, Mohan (2007) Studied fishery and exploitation of E. affinis from north Andhra Pradesh waters and Vinjham respectively. Wang S.P., et al. (2009) estimated the stock assessment of eastern Pacific Ocean big eye tuna (Thynnus obesus) in Taiwan Shimose,T. et al(2009).Studied the age determination and growth of pacific blue fin tuna,(Thynnus orientalis) from Taiwan and Japan waters.

Material and method : 

Material and method Location: college of fisheries and CMFRI regional centre veraval Year and season of experiment: 2010 – 2011

METHOD: : 

METHOD: Multi stage stratified random sampling method (CMFRI 2009) will be followed for the estimation of the monthly and annual catch of E.affinis landed by gill-netters at veraval harbor. In this method fishes will be stratified into multistage size groups will be collected from the veraval.

Materials : 

Materials Measuring tape. Weighing electronic balance. Sampling container Forceps Scissor Label Field note book Formalin Trinocular microscope Ocular and stage micrometer Computer with FISAT software (FAO ICLARM) Stock assessment tools software.

continue : 

continue Length- weight relationship will be calculated separately for both sexes according to Lecren, (1951)as mentioned below. W=aLb Where w=weight, a=constant L=length =slope b  Von-bertanlffy growth parameters viz: growth coefficient (K), asymptotic length (L∞),will be analyzed using the ELEFAN-I(Electronic length frequency analysis)module of FISAT software.(Gayanilo et al.1996)  The growth performance index will be calculated from final estimates of asymptotic length(L∞) and growth coefficient (K)(Pauly and Munro,1984)

Continue…. : 

Continue…. The age at zero length (t0) will be calculated from pauly(1979)empirical equation given below Log(-to)=0.392-0.275logL=1.0381K where to= age at zero length L = asymptotic length K= growth coefficient  Natural mortality (M) will be calculated by Paulys empirical formula(pauly,1980).Total mortality (Z)will be calculated from length converted catch curve using FISAT software (pauly,1983).Fishing mortality(F)will be estimated as per( pauly,1980) F=Z-M where F=Fishing mortality Z=Total mortality M=natural mortality

Continue…. : 

Continue…. Exploitation ratio (E)will be estimated from the equation given by Narsimham(1994). E= F/Z where F=Fishing mortality Z=Total mortality Maximum sustainable yield will be calculated by the equation for exploited fish stocks given by Gulland,(1979) MSY=Z×0.5×B Where Z=Total mortality   B=Biomass The relative yield per recruit (Y/R) and biomass per recruit (B/R) at different levels of fishing mortality will be estimated using LFSA Package (sparre,1987).

Continue…….. : 

Continue…….. The month wise –sex ratio will be determined &chi-square test will be performed to test the homogeneity of male and female distribution (Narsimham, 1994).  Maturity will be observed according to the stages given by James et al.(1987)and size at first maturity will be determined by plotting the percentage of mature specimens (stage3 & above)against their total length.   Fecundity will be calculated by gravimetric method by preserving ovaries in 5% formalin .The ova will be obtained from the anterior, middle and the posterior regions of the eggs (James et al.1978)

Continue…….. : 

Continue…….. The gonadosomatic index (GSI)will be calculated by the formula given by kume and Joseph.(1969). GSI=weight of gonad/weight of fish ×100   The ova diameter distribution in each sub sample of the ovary will be studied under a trinocular microscope using calibrated ocular micrometer (Narsimham 1994) The relative importance of various food items in the stomach will be calculated by the index of relative importance (Pinkas et al. 1971).The IRI will be calculated as given below. IRI = (%N+%V) ×%F Where N=numbers V= volume F= frequency of occurrence

OBSERVATIONS TO BE RECORDED:BIOLOGICAL PARAMETERS : 

OBSERVATIONS TO BE RECORDED:BIOLOGICAL PARAMETERS

POPULATION DYNAMICS PARAMETERS: : 

POPULATION DYNAMICS PARAMETERS:

13. Statistical analysis : 

13. Statistical analysis . Results: will be statistically analyzed using standard methods as per analysis of covariance (Snedecor & Cochran, 1967) and chi-square test (Le-cren, 1951) No of replication: (25 fishes per sampling).

Reference : 

Reference Andrade and Campos (2002) Allometry coefficient variations of the length-weight relationship of Skip Jack tuna (katsuwonus pelamis) from the south west south Atlantic waters. J. of Fisheries Research .Vol.55,pp307-312.   Abdussamad, E.M. Pillai,P.P., Kasim,H.M., and Balasubramaniam,T.S. (2005). Fishery and population characteristics of coastal tunas at Tuticorin.of Journal Mar. Biol. Ass. India, Vol.47,pp 50-56.   Anonymous (2006) A working document IOTC-SC-INFII compilation of information on neretic tuna species in Indian Ocean.

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Continue… Central Marine Fisheries Research Institute (CMFRI) Annual report 2010, pp 27-29   Gopakumar, G., and Sadasiva Sarma,P.S.(1989). The present status of coastal tuna fishery at Vizhinjam, Trivandrum. Mar. Fish. Infor. Serv. T and E Serv.,Vol. 97,pp 1-7.   Gayanilo,F.C.Jr.,sparre,P.,and Pauly,D.,(1996).The FAO-ICLARM stock Assessment tools (FISAT)users guide FAO computerized information series (Fisheries)No. 8,Rome,FAO,126pp.

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Continue… Gulland, J,A.,(1979).Report of the FAO/UNDP workshop in the fishery resources of the western Indian ocean-south equator..FAO, Rome, IOFC/DEV/79/45:1-37. Ghosh, S., Pillai,N.G.K.,and Dhokia,H.K., (2006) A study on fishery and population characteristics and yield estimates of coastal tunas at Veraval. CMFRI(central marine fisheries research institute )Cochin.  Ghosh, S.,Pillai, N.G.K.,(2010). Fishery, population characteristics and yield estimates of coastal tunas at Veraval Indian Journal of Fisheries.Vol.57 (2), pp 7-13.

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Continue.. James, P.S.B.R.,Gupta,T.R.,and Shanbhogue,S.L.,(1978). Some aspects of the biology of ribbon fish (Trichiurus lepturus) Linnaeus off Kakinada.J. of Marine Biological Association .India,Vol. 36,pp: 23-27.  Kume,S., and Joseph,J., (1969).Size composition and sexual maturity of Gill fish caught by Japanese long line fishery in the pacific ocean east of 130 degrees W.bull.FR Sears fish Res.lab.No2  Khan, M.Z.( 2004.) Age and Growth, Mortality and stock assessment of Euthynnus affinis (Cantor) from Maharashtra waters. Indian Journal of Fish., Vol. 51,pp:209-21

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Continue.. Kasim, H.M. and Mohan,S. (2007). Tuna Fishery and Stock Assessment of component species off Chennai coast. In: Book of Abstracts, 8th Asian Fisheries Forum. 58-59 Le cren , E.D., (1951).The length weight relationship and size weight cycle in gonad weight and condition in the perch (perca fluviatus).J.Anim.Ecol.Vol.20:201-219. Lessa,R., and Duarto-neto(2004) Age and growth of yellow fin tuna(Thynnus albacores) in the western equatorial waters using dorsal fin spines.J. of Fisheries Research Vol.69,pp 157-170 .

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continue Madhu, K., R. Madhu, S.P.S. Ahlawat, E.K. Ravindran and S. Dam Roy 2002. Status of exploitation of tuna, mackerel and seerfish in Andaman and Nicobar Islands. In: Management of Scombroid Fisheries, Pillai, N.G.K., N.G. Menon, P.P. Pillai and U. Ganga (Eds.), Central Marine Fisheries Research Institute, Cochin. 49-55. Mohanraj.G., Nair,K.V.S., Asokan, P.K.,ad ghosh,S., (2007) Status of marine fisheries in Gujarat with strategies for sustainable and responsible fisheries.In:Book of Abstracts,8th Asian Fisheries Forum, 85PP, Central Marine Fisheries Resaerch Institute.   Narasimham, K.A. (1994) Fishery and population dynamics of the ribbon fish Trichiurus lepturus Linnaeus off Kakinada..J.of marine Biological Association. India,36 (1&2): 23-27.

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Continue…. Mohanraj, G., K.V.S. Nair, P.K. Asokan and S. Ghosh 2007. Status of marine fisheries in Gujarat with strategies for sustainable and responsible fisheries. In: Book of Abstracts, 8th Asian Fisheries Forum. 85 pp.   Narsimham,K.A.,(1994).Mortality, spawning and sex ratio of the ribbon fish Trichiurus lepturus Linnaeus off Kakinada. J. Mar. Biol. Ass. India, 36(1&2) :199-204.   Darvishi,M., Behzadi,S.,Salapur A. (2003) A Study on the Population Dynamics of E affinis off the Hormuzgan province waters (Persian gulf and Oman sea). J. of Animal and Fisheries science Vol.16 pp 84-89.

Continue.. : 

Continue.. Pillai, N.G.K..(2007).Report on the Tuna Fishery in India with particular reference to long tail tuna (Thynnus tonggol),Central Marine Fisheries Research Institute Cochin India. Pinkas L.,Oligophant, M.S., and Iverson,I.L.K.,(1971).Food habits of Albacore, Blue fin tuna, and Bonito on California waters.Sacromento;California department of fish and game, Fish BullVol.152: 1-139. Pauly,(1979).Theory and management of tropical multi-species stocks. A review with emphasis on the south-east Asian Demersal fisheries. ICLARM studies and reviews, 1,35pp. Pauly D.(1980) On the Interrelation ships between Natural mortality, Growth parameters and mean environmental temperature in 175 fish stocks, L.Cons.Ciem,39(2),175-192.

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Continue… Pauly D.(1983)Length converted catch curves. A Powerful tool for Fisheries Research topics (part-I) ICLARM fish byte 1(2),9-13. Pauly.(1984)length converted catch powerful tool for Fisheries Research in topics (part-iii) ICLARM fish byte ,1(2),13-14. Pauly, D.and Munro, J.l.(1984).once more, on the composition of growth in fish and invertebrates ,fish byte,, 2(1):21. Dayaratne P. and De-Silva J.(1991).An Assessment of Euthynnus affinis on the west –coast of sri- lanka.J. of Asian fisheries science Vol.4,pp:219-226. Snedecor, G.W.and Cochran, W.G.(1967).Statistical methods ,oxford and IBH publishing CO., Calcutta, 593pp.

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continue Sparre, P.(1987) Computer programming for fish stock assessment. Length based fish stock assessment (LFSA) for apple computers. FAO Fisheries Technical Paper,101(suppl 2.). 217pp.   Sujatha, K. and V.A. I. Deepti( 2006). Tuna fish resources of North Andhra Pradesh – sustainable development. In: Sustain Fish, Kurup, B.M.and K. Ravindran (Eds.), School of Industrial Fisheries, Cochin University of Science & Technology, Cochin. 421-433.   Wang S.P.,and Maunder,Mark,N.(2009).Implications of model and data assumptions on the eastern pacific ocean big eye tuna (Thunnus obesus).Journal of Fishery research ,Vol.97,pp 118-126.   Shimose T.(2009) Age determination and growth of pacific blue fin tuna (Thunnus orientalis) off Japan and Taiwan . J. of Fisheries Research :134-139. Chiou W. D.et al(2004) Reproduction and food and feeding habits of kawakawa(Euthynnus affinis)in Taiwan J. of fisheries Soc.31(1):23-38.

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