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Marine

Research and Management

Editors

V.N. Pillai and N.G. Menon

Central Marine Fisheries Research Institute

(Indian Council of Agricultural Research) Tatapuram P.O., Cochin-682 014

Kerala, India

2000

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18 The Indian oil sardine

A.A. Jayaprakash and N.G.K. Pillai

ABSTRACT

The Indian oil sardine, Sardinella longiceps Val, supports a neritic pelagic fishery contributing 2 to 33 % oj the annual marine fish production in India. Though distributed all along the Indian coast the species sustains a commercial fishery ojhigh magnitude along the coasts of Kerala, Karnataka , Goa and southern part oJ Maharashtra. During the last fifty years the annual all India pro- duction oscillated between 14.000 t in 1952 to 3 lakh t during 1968.

Presently the west coast indicates a declining trend compared to an ascending pattern along the east coasl. The production from east coast surpassed that of the west coast contributing 52% of the all India production of 2.03 lakh t in 1998. The fishery along the west coast is known for its fiuctuating nature. Further, the species indicates a cyclic pattern of abundance. A variety of traditional gears were engaged in exploiting the resource till the introduction of modern and sophisticated gear like the purse seines in the late seventies and the ring seines in the late eighties. In fact oil sardine is one among the few species that have ever remained a subject matter of intensive research. The focus of this com.pilation is to present a comprehensive picture of the Indian oil sardine, its fish- ery, biology, stock, future prospects of exploitation and management measures needed for yield optimisation.

Introduction

The pelagic fisheries resource contributed 4 5 - 6 1 % to the total ma- rine fish production of 2.2 million tonnes during 1985-94. The clupeoids com- prise a major group among.tfie pelagic resource. Among the clupeoids, the Indian oil sardine [SardineUaSTongiceps Val.) known a s 'Mathi/Nalla mathV in Malayalam,'Boothai' in Kannada, 'Tarli/Haid' In Marathi, 'Noone-kauallu' in Telugu, 'Nonali/Paichaldi' in Tamil is the most predominant species t h a t forms the m a i n s t a y of the pelagic fishes of India a n d its stock is probably the widespread in the Indo-Paciflc region. The species s u p p o r t s a commercial

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Marine Fisheries Research and Management

fishery extensively in the inshore waters of the west coast (8" N a n d 16" N) from Quilon to Ratnagiri. Its contribution to the total m a r i n e fish landings varied from 2 to 3 3 % during 1960 to 1995. In the recent p a s t the highest landing of 3.00,000 t o n n e s was recorded in 1968 a n d a lowest of 4 7 , 0 0 0 t in

1994. The fish is m u c h s o u g h t after a s a favourite food item. During the early years a n d at times of glut it is also u s e d for extraction of oil a n d a s m a n u r e . The large scale fluctuation in a b u n d a n c e , the population c r a s h e s and s u b s e q u e n t revival of the fishery have ever remained a subject of centre stage attraction from very early,times. Many r e s e a r c h e r s from time to time have focused their attention to investigate a host of fishery i n d e p e n d e n t a n d fishery d e p e n d e n t factors t h a t influence the oil s a r d i n e a b u n d a n c e a n d came out with different suggesions. The d i s c u s s i o n h e r e a t t e m p t s to bring out precisely the p r e s e n t s t a t u s of our knowledge on the oil s a r d i n e , its fishery, biology, stock and identify a r e a s which require further Investigation for the o p t i m u m exploitation a n d m a n a g e m e n t of the r e s o u r c e . Material for this discussion is based on the publications in l i t e r a t u r e . Details of the p r e s e n t exploitation is t a k e n from the records of NMLRDC of CMFRI.

History at a glance

Pioneering works on the seasonal and a n n u a l migrations of oil sardine are those of Hornell (1910), Hornell and Nayudu (1924), Devanesan (1943) and Nair (1951 b ,1960) and Panikkar (1960).

The a n n u a l fluctuations encountered have been reported by Day as early as 1865 T h u r s t o n (1900) and Hornell (1910). Later, Nair a n d C h i d a m b a r a m (1951), Nair (1960, 1973), Antony Raja (1972), Balan and Reghu (1979) and Balan (1984) have also dealt extensively on this aspect.

The fishery and biological a s p e c t s have been extensively described in the works of Annigeri (1969, 1987, 1992), Anon. (1947. 1960, 1969, 1972, 1973, 1974, 1975, 1976), Antony Raja (1973), Balan (1972, 1973, 1984), Balan and Reghu (1979), Balan and Nizar (1988), Bensam (1970), Chacko and Mathew (1956), C h a k r a b o r t y et al (1975) , D e v a n e s a n (1943), D e v a n e s a n a n d C h i d a m b a r a m (1953). D h u l k h e d and U m a k u m a r i (1979), D h u l k h e d et al (1982), Dhulkhed and Uma Bhat (1985). Foetadar and Savaria (1988), J a c o b et al (1982), J a m e s (1981), Kaikini (1960), K u r u p et al (1987), Nair a n d P r a s a n n a Kumari (1973), Noble and Kutty (1978), P r a b h u (1971), P r a b h u

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The Indian oil sardine a n d D h u l k h e d (1970), R a d h a k r l s h n a n (1965), Rengasamy (1977), Sam Bennet (1965), S e k h a r a n (1962), S e k h a r a n and Dhulkhed (1963) a n d S e k h a r a n a n d Nair (1976).

Significant contributions to the knowledge of spawning biology have been m a d e by Antony Raja (1964, 1966, 1967, 1971), Balan (1965, 1972), Dhulkhed (1964, 1968), D h u t t (1968), Lazarus (1976, 1985) a n d Nair (1960. 1973).

Our knowledge on the spawning grounds and eggs a n d larvae of s a r d i n e Is limited to the works of Anon. (1974, 1976), Devanesan a n d C h i d a m b a r a m (1943), Devanesan (1943) and George < 1976, 1980). The early life history h a s been described by Nair (1959).

Many workers while studying the fishery a n d biological a s p e c t s have dealt with the age a n d growth. But s t u d i e s exclusively on age a n d growth have b e e n m a d e by Antony Raja (1970). B a l a n (1959, 1964), B e n s a m (1968), Dhulkhed (1977) a n d Gjosaetor et al (1984).

S t u d i e s on the food a n d feeding h a b i t s are those of Hornell (1910), Hornell and Nayudu (1924), Devanesan (1942, 1943), J o h n a n d Menon (1942), Nair (1953 b), Nair a n d S u b r a m a n y a n (1955), Chacko a n d Mathew (1956 b), Kuthallngam (1960, 1961), Dhulkhed (1962, 1970), Bensam (1964 c), Kagwade (1964) a n d Noble (1964). Results of the racial investigations are available from the works of Dhulkhed a n d Nagesh (1976) a n d Menezes (1975, 1980).

Accounts on t h e fishery a n d biology of oil s a r d i n e from t h e e a s t c o a s t have been reported by G n a n a m u t h u and Glrljavallabhan (1984), Kumar a n d B a l a s u b r a m a n i a n (1987), Luther (1988, 1994), M a h a d e v a n Plllai (1992), M a r i c h a m y et al (1992), R a m a s o m a y a j u l u a n d D h a n a Raju (1985) a n d S r i n i v a s a r a n g a n a n d C h i d a m b a r a m (1985). The p h e n o m e n a l i n c r e a s e in t h e landings of oil s a r d i n e on the east coast in recent years awaits a serious study.

The Central Marine Fisheries Research Institute h a s p u b l i s h e d a n a n - n o t a t e d b i b l i o g r a p h y on oil s a r d i n e c o v e r i n g all l i t e r a t u r e u p t o 1 9 8 9 (Girijakumari, 1990)

Distribution and variability

The general distribution of Sardinella longiceps is reported to b e along the coast of SomalUand, Mombasa, Seychelles, Gulf of Aden, Red Sea, Gulf of

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Marine ri»herle» Re«earch and Management

Oman, Persian Gulf, Pakistan, India, Sri Lanka, Andaman Sea, Malaysia, In- donesia, Philippines a n d Vietnam.

Studies on the variability of some morphometric a n d meristlc c h a r a c - t e r s of the species from different centres along the Indian coast, Aden, Mus- cat a n d Karachi indicated t h a t there were no local racial or brood differences (Hornell a n d Nayudu, 1924). Devanesan a n d C h i d a m b a r a m (1943) have ex- pressed the possibility of the existence of different r a c e s . Those from some region of the Indian coast differed from those from Aden and Muscat. They have further observed t h a t the oil s a r d i n e from Karwar seems to differ from that-of the Malabar a n d Bombay - Karachi coasts in certain c h a r a c t e r s i s t i c s of the h e a d and tail.

Food and feeding

Large quantities of flocculent muddy unrecognisable m a t t e r was found in t h e s t o m a c h c o n t e n t s during October-December. It w a s observed t h a t the fish fed on s u c h m u d d y m a s s at the sea-floor, exhibiting preference for bot- tom feeding (Hornell a n d Nayudu, 1924). This m u d d y material was only a well digested form of diatoms a n d other planktonlc o r g a n i s m s a n d t h a t the bottom fetedlng habit could be only occasional due to unfavourable conditions near t h e surface (Devanesan, 1943). However, the movement of s a r d i n e s towards the bottom is a common occurrence d u r i n g October to J a n u a r y (Balan, 1962) and this may possibly explain the bottom feeding h a b i t s .

The fish is a plankton feeder and mainly feeds on diatoms, dlnoflagellates, t l n t l n n l d s a n d z o o p l a n k t o n . A m o n g t h e d i a t o m s , Fragilaria oceanica, Pleurosigma, Coscinodiscus, Biddulphia and Trichodesmlum thiebautii were frequent. Those belonging to Dlnophyceae consisted of Procentrum, Ceratium, Peridinium; a n d a m o n g z o o p l a n k t o n Acrocalanus, Paracalanus, Oithona, Harpactlcolds, Lucifer and larval polychaetes have been noticed. The juve- niles are carinlvorous a n d post-larvae feed on diatoms and algae. The diatom F.oceanica Is said to probably indicate a b u n d a n c e of oil s a r d i n e in coastal w a t e r s . During spawning, there seems to be a cessation of feeding activity.

The observations of various resfearchers are s u m m a r i s e d in Table 1.

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The lodian oil sardine T a b l e 1. O b s e r v a t i o n s on t h e food a n d feeding h a b i t s of Sardinella

longiceps «

Observation Author & year

Juveniles are carnivorous, and adults feed on Phytoplankton. Indirect selection by their inefficient filtering mechanism In Juveniles lead to carnivorous diet.

Normally feed on fish eggs off Calicut. Also diatoms and dlnoflagellates

Recorded 1) Diatoms: Cosctnodicus, Frc^ilaria oceanica, Biddulphia, Pleumsigma, Nitzchia, Rhizosolenia, Asterlonella, Bacteriastrum, Dttylum, Hemidiscus, PlanktcmieOa, Thaiasiothrix

and Triceratium; 2) Dinophyceae; Dino[^sts, Procentnun, CeretWum, PerkUnium, Pyrc^f^vacus and OmUhotXTCus; 3) Tintlnnids; 4) zooplanktons like Aerocakmus, Paracakuiua, Oithcma cmd Heapaetkoids.

Food of Juveniles (40-79 mm) were diatoms, dlnoflagellates, copepods and bivalves. More dlnoflagellates with increase in length Feeding on flocculent muddy scum at sea bottom during October-December.

Nearly 90% of the food consisted of greenish and brownish mud indicating preference for bottom feeding, recognisable matter consisted of diatoms and dlnoflagellates.

Mainly feeds on diatoms and dlnoflagellates Diatoms, dlnoflagellates and zooplankton. The blue green algae Trichodesmiwn thtebautttwas frequently observed.

Food of larvae consisted of diatoms and algae, compared to copepods,ostracods, Lucifer, larval

Bensam(1964)

Devanesan(1942, 1943)

Dhulkhed(1962)

Dhulkhcd (1970)

Homell(1910)

Homell & Nayudu (1924)

John &Menon (1942) Kagwade(1964)

Kuthallngam (1960)

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Marine Fi«herie« Rpaeiurch and Management prawns, bivalves and polychaete larvae, serge- stids, diatoms an3 algae in adults.

Phytoplankton formed chief food item of Juvenl- Nair (1953 b) les and adults

Diatom Fragilaria oceanica can be an Indica- Nair and Subramanyan (1955) tor species for sardine abundance

Domination of diatoms in July-Sep. & Dec-Feb., Noble (1965) copepods at other times. Even during blooms

of F.oceanicxi catch was poor, hence ruled out the possibility of this diatom as indicator species.

Age and growth

Different views have been expressed by various experts a b o u t the age, growth r a t e and life s p a n of this fish. On the b a s i s of length frequency d a t a Hornell and Nayudu (1924) have concluded t h a t the fish grows to a length of 155-170 mm in one year a n d 190 mm In two y e a r s . They also p o s t u l a t e d t h a t spawning t a k e s place a t the end of the first a n d second years of Its life. The life s p a n w a s p r e s u m e d to b e 2.5 y e a r s . According to C h i d a m b a r a m (1950) the fish a t t a i n s 100, 145, 183 a n d 205 mm at the end of first to fourth year respectively. Nair (1953) after examining the rings on scales and otoliths came to almost the s a m e conclusion as C h i d a m b a r a m . Antony Raja (1969) is of the opinion t h a t there is differential growth r a t e In the different b r o o d s arising out of early spawning a n d late spawning in the s a m e s e a s o n . The earlier brood spawned in J u n e - J u l y h a s a high r a t e of growth reaching 105 mm in eight weeks, w h e r e a s t h a t spawned In July-August a t t a i n s the s a m e length in ten weeks. Tire m a x i m u m size group on record Is 220-229 mm (Chidambaram, 1950; Rosa a n d Laevastu, 1960). The length frequency a n a l y s i s (Annlgeri et al. 1992) showed t h a t the fish a t t a i n s 128 mm, 166 mm a n d 195 mm at the end of 1,2 a n d 3 y e a r s respectively. Results of observations on the age and growth of t h i s species by different a u t h o r s are s u m m a r i s e d In Table 2.

Table 2 Results of the age and growth s t u d i e s on Sardlnella longiceps

Observations Area Author Attains 117,172.192,210 ram at the end of 1 West coast Annlgeri et al (1992)

to 4 yeai-s. LQO = 221 mm, K = 0.75 (annual) by VBG (1938); Loo =231 mm,K=l.52 by

"264"

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The Indian oil sardine Bhatacharya method (1967); LQO = 225 mm,

K=0,73 by Wetheral et al (1987) method.

Attains 95-110, 110-125, 125-140, 150-160 and 170-180 mm at the end of 2,3,6,12 and 24 months. Estimated value of LQO

=209.8mm, K=0.05 to =13.42,normal life span 2.5 years.

Scale studies- the fish attained 143, 164 &

184mm at the 1,2 &3 years respectively.

Loo = 207 mm, K=0.53 (annual), to = 1.33 Attained 145-155 and 175 mm at the end of

1 & 2 years.

Attained 100, 145, 183 and 205 mm at the end of 1 to 4th year respectively. Tmax 4 years.

Attains 140 mm at the end of one year.

The average lengths at ages of 6,12,18 and 24 months were 87.9, 124.4, 156.9 & 172.7 mm respectively.

Attains 155-170 mm by 1st year and 190 mm by 2nd year.

By VBG method obtained a value of 147.72 mm, 172.53 mm and 187.7 mm for 1,11 and 111 year

of life

Calicut 1961-62 to 6^-67

Antony Raja (1973)

Cahcut 1955-65

Cannannore 1936-42

Balan (1959)

Banerji (1973) Bensam (1964)

Calicut Chidambaram (1950) Sri Lanka Dayaratne & Gjosaeter (1986) Mangalore Dhulkhed (1977)

Malabar Hornell & Nayudu (1924)

Parangipettai Kumar &

Balasubramanian (1987) Nair (1949. 1953) 100,145,183,205 mm at the end of 1 to IV year,

growth rings seen in otoliths Inferred to be annual

Attains 150,170, 190 mm at the end of 1 to Cahcut Prabhu (1967) 3 years

Attains 100-110 during 1st year, 150-160 Mangalore 1963-64 Prabhu &

mm in llyear and 175-180 mm in the third year 1967-68 Dhulkhed(1970) Attains 125-130 mm, 165-175 mm and 180- Calicut 1970-71 to 1973-74 Rengasamy (1977)

190 mm at Calicut ^at 1967-68 the end of 1 to 3 years

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Mrlne Fl«herie« Re»earch and Management

Av.length at age of Six, twelvcelghteen and 1960-73 twenty four months being 87,9,124.4,156.9

and 172.7 mm.

128, 166, 195 mm at the end of I, II, 111 years. West coast 1984-88

Dhulkhed (1977)

'^00 197.2 mm, K= 1.006 (annual) West coast

Kumaranefal (1992) Kurup etal (1987) Length-weight relationship

D h u l k h e d (1967 a) worked o u t t h e length-weight a n d volume relation- ship of the species from Mangalore a n d derived a t the following equation:

Length- weight I n d e t r e m l n a t e Female Male Pooled

-7.6541 + 3.6169 log L -6.3420 + 3 . 2 6 6 5 log L -6.7010 + 3.1086 log L -6.4662 + 3.2123 log L

Length-volume -7.6599 + 3.5940 log L -6.4108 + 3.5940 log L -6.6944 + 3.1091 log L -6.3439 + 3 . 2 6 2 3 log L Antony Raja (1967) also carried out a n analysis of his d a t a for five sea- s o n s a n d could not find a regular sequence of decreasing values of 'b' among the Indeterminate, female a n d male fishes.

Reproduction

Sexes are s e p a r a t e . In s p e n t and recovering fishes males could be dis- tinguished by a n externally visible m u s c u l a r papilla In the cloaca a n d in fe- males by the p r e s e n c e of a m e m b r a n o u s papilla behind the a n a l opening.

Oil s a r d i n e a t t a i n s sexual m a t u r i t y at the age of one year at a length of 150 mm. Active s p a w n e r s in the oozing condition m e a s u r e 150 to 170 mm.

Fecundity varies from 70,000 to 8 0 , 0 0 0 ova, b u t averages to 4 8 , 0 0 0 eggs. The fecundity is directly proportional to the weight of the ovary and Is generally related to the size of t h e fish.

The sex ratio appear to vary. Some Investigators found the females to predominate u p t o size at first maturity, b u t reduced segregation among ripe fish. A recent s t u d y by Annigerl et al (1992) indicated t h a t the females domi- nated at all observation centres both on the east and west coast.

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The Indian oil sardine T h e s p a w n i n g s e a s o n is protracted with certain a m o u n t of i n t e r a n n u a l variations in its d u r a t i o n . In general, it extends from May to October with intense activity during J u n e to August.According to Nair (1959) the fish s p a w n s only once in its life b u t Antony Raja (1967) h a s pointed o u t the c h a n c e s of spawning twice before t h e end of its flshable Ufe-span. D h u l k h e d (1967 b) is of the view t h a t eggs are discharged in 3 to 4 b a t c h e s during the spawning season, though Antony Raja (1967) disagrees with this observation. The spawn- ing g r o u n d s have n o t been definitely located yet. It is s u p p o s e d t h a t spawn- ing is found to take place at a b o u t 15 km from the shore at 30 m depth line in the surface a n d c o l u m n a r s t r a t a from Quilon to Karwar. Isolated cases of spawning in the n e a r s h o r e a r e a s also have been observed off Kasaragod a n d a t Cochin d u r i n g J u l y . Spawning u s u a l l y t a k e s place a t night, a few days before a n d after new moon s u g g e s t i n g t h e influence of l u n a r periodicity (Devanesan a n d C h i d a m b a r a m ,1943 a n d Antony Raja, 1969). A m e a n rain- fall range of 2 0 - 3 0 mm for J u n e - A u g u s t may indicate good r e c r u i t m e n t . It h a s been found t h a t s e a s o n s of feeble or severe rainfall coincided with extensive atresia in t h e ovaries leading to reduction in spawning potential of the popu- lation (Antony Raja, 1973). The observations of various a u t h o r s are s u m m a - rised in Table 3 .

The eggs in p l a n k t o n were collected off Kerala coast a n d its early life history h a s b e e n worked out (Nair a n d S u b r a m a y a n , 1955). The eggs are pelagic, t r a n s p a r e n t , spherical a b o u t 1.4 mm in diameter with a wide periv- itelline space. The yolk is colourless a n d h a s distinct segmentation. Gener- ally only one b u t occasionally two and rarely three spherical oil globules have been observed (Nair, 1959).

Table 3. Spawning season, size at maturity of oil sardine along the west and east coast

Author

1

Year

2

Area

3

Period

4

Maturity, spawning, sex ratio, fecundity,eggs and larvae 5

West Cout Anon Anon

(1974) UNDP/FAO/PFP (1975) UNDP/FAO/PFP

Spawning in isolated local patches in nearshore waters (12m)off Kasaragod and Cochin Young oil sardine observed during April-Aug. &

Nov., February.

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Marine Fiaheriea Reaearch and Management Anon (1976) UNDP/FAO/PFP Annigeri (1969) Karwar Antony Raja (1964) West coast Antony Raja (1969) Calicut Antony Raja (1971) Antony Raja (1973) West coast

Balan

Balan Balan

(1966) Cochin

(1972) Cochin (1973) Cochin

Balan eta! (1979) West coast

Balan andNbar (1988) Cochin Bensam (1970) Cannanore Chackoand (1956) West coast Mathew

Chidambaram (1950)

Chidambaram and( 1946) Calicut Venkataraman

Devanesan (1943) Malabar

Devanesan and (1948) Chidambaram

Spawning season April-August.

1964-65; Spawning during July, August to November- December, size at maturity 140mm.

1959-63 Spawning season July-August.

1959-60 Male matures earlier. No significant change in sex ratio Average fecundity 37,000-38,000. Older fishes have higher values of fecundity.

1956-57 25-35mm rainfall during June-July or 1972-73 20-30mm forJune-Aug.

favours good recruitment. Feeble or excess rain leads to atresia, thereby reduction in spawning potential.

1959-63 Average fecundity 48,119. Females dominated during 1959, 60, 61, 62, 64 and 65 in the boat seines at Cochin.

1959-69 Spawning season June to August.

1969-71 No significant dominance of either sex in purse seine catches at Cochin during 1969-71.

In 1978, females dominated at Calicut, Cochin and Karwar, but males at Mangalore.

1980-85 Spawning June to August.

1961-63 Spawning April to August.

1954-55 Mature and spent fishes occurred during April-August.

Females dominated above 200 mm size, equal proportions of sexes upto 200 mm.

Size at maturity 150mm.

Fecundity 70000-80000. Size at maturity 150mm.

Active spawners and planktonic eggs during September-October.

Fecundity 70000, sex ratio equal below 200 mm length fishes.

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The Indian oil tardine

Dhulkhed

Dhulkhed Dutt

Hornell

Hornell and Nayudu

(1964)

(1968) (1968)

(1910)

(1923)

Mangalore

Malabar

George

George

Lazarus

Lazarus

Nair Nair

Nair

Nair and Chidambaram Prabhu

(1976) UNDP/FAO/PFP1971-75

(1980) Ratnagiri 1971-75

(1976) Vlzhinjam

(1985) Vizhinjam

(1959) (1960)

(1973)

(1951)

(1967)

Spawning takes place at night, spawns few days before and after the new moon day.

Malpe and Kasaragod Release eggs in 3-4 batches. Size at maturity 165-169mm.

Spawning time from June tp September. Hardly any difference in sex ratio.

Different broods were noticed indicating extended spawning.

Spawning during June to August and takes place earlier in north than in southern areas.

Dominance of females upto size at maturity, reduced sexual segregation among

adult fishes.

Peak spawning from April to August, close to shore in area 11 30'N.

From 1409 stations UNDP/FAO/PFP sporadic large collections of eggs during July and August.

Spawners and spent fishes occur at Vizhinjam farther off the usual fishing grounds.

Spawning and spent fishes occurred at Vizhinjam during May 1976 from farther off the usual fishing grounds.

Spawning grounds beyond the present fishing zone.

Fecundity 78000. Sex ratio equal among juveniles and spawners. The left ovary produced 40000 eggs and the right ovary 38000 eggs.

Reviewed various aspects such as spawning, fecundity, development of eggs and larvae stages Estimated fecundity 75000.

Reviewed the biology. Spawning appeared to be

< : 2 6 9 >

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Marine FtoheriM Research and Management

Radhakrishnan (1965) Karwar 1955-64 East CoMt

Gnanamuthu& (1984) Madras 1988 Girijavallabhan

Gnanamuthu& (1989) Madras 1987 Thankaraj

Gnanamuthu etal (1989) Madras

Kuthaiingam (1960) Madras Kumar & (1987) Paranglpettal

Balasubramaniam

Luther (1988) East coast 1961-86

Maricharay etal (1992) Rameswaram 1991-92 Mandapam

Srlnivasarangan& (1985) Pondicherry 1983 Chidambaram.

protracted extending from July to October/

November. Spawning ground not far away from the fishing ground.

Observed the maturity and spawning

Mature fishes occurred during January-March.

Males dominated.

Mature fishes occurred during January-March.

Protracted spawning along west coast, May-June to September- October.

Described the larvae from hatching to 40th day.

Size at maturity 156mm for females and 158.5mm for males.

Spawning during July to September.

Spawning during March-April. Juveniles 50-80mm occur by May at Visakhapatnam.

Females dominated during October to January.

All specimens were in spent recovering stage.

Females dominated during November-December.

Embryonic development is rapid and completed in a b o u t 24 h o u r s . The newly h a t c h e d larva a b o u t 2 . 7 5 mm in length floats in w a t e r with t h e help of t h e oil globule a n d yolk. T h e one-day old larva, m e a s u r i n g 3.35 mm in aver- age length shows great r e d u c t i o n in t h e yolk a n d loss of oil globule. The two-day old larva becomes active in its m o v e m e n t s a n d grows to a b o u t 3.7 mm In length. Most of t h e yolk Is a b s o r b e d by t h e time t h e m o u t h is well developed. The t h r e e - d a y old larva s h o w s no specific features except slight r e d u c t i o n in length d u e to complete a b s o r b t i o n of yolk.

S h o a l i n g and m i g r a t i o n

I n t e r e s t i n g o b s e r v a t i o n s on t h e different types of surface a n d bottom s h o a l s have been described by Balan (1961). Shoals have been differentiated i n t o flipping, p a t t e r i n g , r i p p l i n g , c o l o u r e d , l u m i n l s c e n t , b u b b l i n g a n d

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The Indian oil sardine odourlferous. Of t h e s e the first five types of s h o a l s are generally seeri a t t h e surface a n d the last two at t h e bottom of the sea. The flipping s h o a l s are reported to occur both during day a n d night, b u t more common in the m o r n - ing a n d a t night. The pattering s h o a l s are found more d u r i n g the day t h a n a t night p r o d u c i n g s o u n d s simultaneously or in s u c c e s s i o n . The rippling s h o a l s produce ripples on t h e surface of water. Besides t h e s e , b a s e d on t h e behav»

lour p a t t e r n s the s h o a l s are further differentiated by the colour effects they produce a s b l u i s h a n d pinkish coloured shoals. There are also l u m i n e s c e n t s h o a l s easily c a u g h t d u r i n g d a r k n i g h t s . The p r e s e n c e of a series of small air b u b b l e s coming from below a n d b u r s t i n g on the surface water are believed to be released by t h e fish while feeding on m u d d y bottom. This m a k e s t h e m a n easy target to fishermen. Good concentration of fish is also Indicated by the strong fishy odour. The size of the shoal may range from 2 to 2 5 m length a n d 1 to 20 m b r e a d t h . The s h a p e of the shoals vary. They are roughly pointed in front a n d b l u n t behind. The pattering type of shoals are, however, re- ported to be oblong a n d the bluish ones somewhat n a r r o w b u t long. The speed of the surface s h o a l s is a b o u t 5 km per h o u r . The cruising capacity of the b l u i s h a n d p i n k i s h s h o a l s is m u c h lower t h a n t h a t of t h e rippling type.

The '0' year class migrate en masse from offshore to Inshore a r e a s si- multaneously at all centres on the west coast by the end of southwest monsoon.

The new r e c r u i t s continue to get reinforced u n i t e r r u p t e d l y in spite of heavy fishing p r e s s u r e . With the warming u p of water in s u m m e r , t h e shoal g r a d u - ally move offshore first from the n o r t h and from s o u t h s u b s e q u e n t l y . Tagging e x p e r i m e n t s

Large scale tagging of oil s a r d i n e w a s carried out by CM.F.R.I from sev- eral centres on t h e east a n d west coast of India during 1967-69 (Prabhu a n d V e n k a t a r a m a n , 1970). Since the recoveries were limited, no definite conclu,- sions could be drawn on the migration other t h a n t h e local dispersal observed.

Fishery

Fishing areas

In India, oil s a r d i n e Is found from Kathlawar to the C o r a m a n d a l a n d Ganjam coast. But commercial concentration is p r e d o m i n a n t along the s o u t h - west coast between 8° N a n d 16° N latitudes. This covers Kerala, K a r n a t a k a ,

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Marine Fl»herie« Research and laanagement

Goa a n d s o u t h e r n p a r t of M a h a r a s h t r a . Of late, its emergence a s a n e s t a b - lished new fishery along the east coast h a s been reported by Luther (1988).

Along t h e west coast the fishing activity is restricted to the region a b o u t 3 to 20 km from t h e shore a t d e p t h range of 5 to 2 5 m. Dense shoals of this fish a p p e a r in the inshore a r e a s along the Palk Bay during December to March period.

Pishing gear

Details of the traditional craft a n d gear engaged in oil s a r d i n e fishery Have been d o c u m e n t e d by Nalr (1973). The boat seine [Mathikolli vala) , the gillnet (Mathichala vala) a n d the shore seine (Rampant) were t h e i m p o r t a n t traditional gears. Several types of specialised n e t s like the b o a t seine {Paithu vala .Pattenkolli vala, Thattum vala, Thangu vala a n d Nethel vala) a n d shore seines [Kamba vala, Kairampani a n d Vendf) with varying m e s h size were also in u s e . The traditional gears progressively became out dated with the advent of efficient gear like p u r s e s e i n e s in the late seventies (Dhulkhed a n d Bhatt, 1985). In Kerala a n d K a r n a t a k a the place of indigenous gear h a s been s u b s t i - t u t e d by ringseine, a simulative p u r s e s e l n e .

Trends in production

The early p a r t of the fishery from 1925-26 to 1968 h a s been reviewed by Nair a n d C h i d a m b a r a m (1951) a n d Nair (1973). During the last fifty years t h e all India production of oil s a r d i n e ranged from 14,000 t in 1952 to a n all time high of 3 lakh tonnes In 1968 (fig 1) contributing 0 . 1 % to 3 1 . 9 % to the total m a r i n e fish -landings In the country. Average a n n u a l landings during

1985-93 on the west coast was 128,282 t (86%) a n d on east coast 21,262 t (14%). The a n n u a l landings in Kerala varied from 1554 t In 1994 to 184,879 t in 1989, in K a r n a t a k a 1631 t in 1994 to 4 5 . 9 0 0 t in 1988 a n d in Goa 2 t in

1994 to 2 2 , 1 8 6 t in 1 9 9 1 . State-wise average (1990-98) catch a n d percentage contribution on the west coast were, Kerala 6.7361t (47.6%), K a r n a t a k a 9,770 t (6.9 %). Goa 5,978 t (4.2%), M a h a r a s h t r a 560 t (0.4%) and Gujarat 66 t (0.08%). Correspondingly, the landings on the east coast were, Tamil Nadu 4 2 , 6 5 6 t (30.2%), Pondlcherry 4.454 t (3.1%), A n d h r a P r a d e s h 10,458 t (7.4%) a n d Orissa 130 t (0.12%).

F i s h i n g s e a s o n

The fishing s e a s o n s t a r t s in J u n e with the a p p e a r a n c e of shoals of fish

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The Indian oil sardine

S60r

ThouMnds

^9«e 1960 1960 1970 1976 1960 1966 1990 19961998

• I Lwdlngs

Fig. 1. All India oil sardine landings in tonnes

Trtnd

spawned in the previous year (Nair 1959, Antony Raja, 1969) at the s o u t h e r n end of the Malabar coast. These shoals further move n o r t h w a r d a n d by the end of F e b r u a r y progressively s t a r t withdrawing s o u t h w a r d along with young recruits (Chidambaram 1950. Antony Raja 1969).

Quarter-wise production (Fig.2)

In Kerala, the peak catch of 2 6 , 5 1 3 t (Av. 1985-93) was d u r i n g the third q u a r t e r (July-September) followed by the fourth q u a r t e r (25,442), first quar- t e r ( 2 4 , 2 5 5 t) a n d s e c o n d q u a r t e r ( 1 2 , 5 9 6 t). In K a r n a t a k a , Goa a n d M a h a r a s h t r a t h e fourth q u a r t e r followed by first q u a r t e r were productive. The landings d u r i n g the last a n d first q u a r t e r s respectively for t h e s e s t a t e s were

11.600 t a n d 9,536 t: 6,021t and 1,950 t; a n d 2,879 t a n d 2 9 5 t.

Trends (Fig.3)

T r e n d s of oil s a r d i n e landing In Kerala d u r i n g the p r e - p u r s e seine pe- riod (1971-75), p u r s e seine period (1976-81) and p u r s e seine a n d ring seine

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Marine Fisheries Research and Management CATCH (Hrousand fcnnas)

KERALA KARNATAKA

• i l Q R O l O l i Q R

QOA MAHARASHTRA ill QR WH IV OR

Fg.2. Quarter - wise production of oil sardine - statewlse

f^IEfkPAE CATCH (THOUSAND TONNES)

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KARNATAKA QOA

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Fg.3. Oil sardln landings (T) during different phases of development

"274"

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The Indian oil sardine period (1987-92) Indicated no Improvements In production despite t h e effi- ciency of t h e m o d e r n gear. In K a r n a t a k a , t h e landings Increased d u r i n g t h e second p h a s e , b u t decreased s u b s e q u e n t l y . In Goa g r a d u a l i n c r e a s e w a s seen from the initial stage to the last p h a s e .

Gear-wise contribution

In Kerala the average (1986-95) oil s a r d i n e landings by different gear w a s , p u r s e seine 3,479 t (4.7%), ring seine 4 6 , 7 4 9 t (63.6%) , trawlers 677 t (1%) and other gears 22,587 t (30.7%). In Karnataka it was: p u r s e s e i n e s 21,194 t (93.8%), trawlers 99 t (0.4%) and other gears 1,311 t (5.8%). In Goa on a n average 6,548 t (98 %) were landed in p u r s e seines and the r e s t In other gears. In M a h a r a s h t r a the p u r s e seines landed 870 t In 1995 a n d 140 t in

1993.

T h e p u r s e seines realised a n average c / e of 6 5 6 kg in Kerala compared to 4 5 9 kg In K a r n a t a k a a n d 138 kg In Goa . In M a h a r a s h t r a It ranged from 8 kg In 1993 to 59 kg in 1995. The ring seines in Kerala reaUsed a n average c / e of 2 4 8 kg. Along the east coast a highest c / e of 2100 kg h a s been reported in the p a i r trawlers at Rameswaram (Marlchamy et al 1992). ThiS high c / e noticed a t Rameswaram may not be a regular p h e n o m e n o n .

The variability in a b u n d a n c e of oil s a r d i n e Is cyclic. The decadal averages of all India production indicate a decreasing t r e n d from 2 , 0 5 , 0 0 0 t in t h e seventies to 1,37,000 t in the first half of the nineties. In fact, when the traditional gears were in operation In t h e sixties the a n n u a l l a n d i n g s were better t h a n t h a t of late seventies. This period u p t o sixties represented a p h a s e of high a b u n d a n c e , b u t the succeeding years appeared to r e p r e s e n t a declining p h a s e . The introduction of p u r s e seines and later the ring seines coincided with the low a b u n d a n c e period a n d h e n c e the total landings of oil sardine showed no Increase despite the efficiency of these gears. On the contrary the indigenous gears d u r i n g the premechanlsed era could realise 3 lakh t o n n e s m 1968.

Oil sardine - an emerging resource along e a s t c o a s t

The exploitation of oil s a r d i n e along t h e east coast till 1988 w a s spo- radic a n d r a r e . B u t It appeared t h a t there exists a variable stock of this re- source along t h i s coast also. Since there was no local c o n s u m e r d e m a n d , the

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Marine Fisheries Re»«arch and Management

stock was left to die a n a t u r a l d e a t h until a time when t h e d e m a n d came from out side the s t a t e . The last decade, henceforth, witnessed large scale exploi- tation of the resource to meet the Increased d e m a n d from Kerala. The produc- tion reached 2 1 , 5 0 0 t in 1989 a n d p l a t e a u e d a r o u n d 3 8 , 0 0 0 t till 1993. The landing was 4 3 , 6 0 0 t in 1994 a n d reached 70,500 t in 1996 a n d to a n evertime high of 111,300 t in 1997 almost equalling 111,400 t realised from west coast.

(Fig. 4). On a n average (1990-98) the east coast contributed 4 0 . 8 % a n d west coast t h e r e s t . Along the e a s t coast 7 3 . 8 % of the production w a s from Tamil Nadu, 18% from A n d h r a Pradesh, 7.7% Pondlcherry, a n d t h e rest from West Bengal and Orissa. The production from this coast s u r p a s s e d the trend along the west coast d u r i n g 1998. D u r i n g t h e year, the east coast contributed 52%

to the all India production of 2 . 0 3 lakh t o n n e s . Interestingly t h e production in all the maritime s t a t e s along the west coast Indicated a decreasing p a t t e r n compared to a n ascending trend discernible along the east coast. Trawls, pair trawls, gillnets, b o a t s e i n e s a n d shoreselnes are engaged in exploiting the re- s o u r c e .

I Etf t OOMt Lliii VMt OOMt EWt OOMt WMt 0<HMt

300

Thousand tonnes

Fg.4. Oil eardlne production East and West coast

"276"

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The Indian oil sardine Utilisation

Oil s a r d i n e is rich in oil a n d the history of t h e oil t r a d e h a s been traced by Nalr (1973). Nicholson (1915) Introduced efficient m e t h o d s of oil extrac- tion. Of t h e two grades of oil produced the refined yellow oil w a s u s e d in leather i n d u s t r y a n d in the a r s e n a l s and the inferior brown oil in t h e j u t e a n d steel i n d u s t r i e s . The oil stood very well in comparison with t h e M a n h a d e n or J a p a n e s e s a r d i n e oil (Nicholson, 1922). The g u a n o , the r e s i d u e , w a s u s e d a s m a n u r e in coffee, tea, coconut, s u g a r c a n e and tobacco p l a n t a t i o n s . Similarly the fish-meal was a n o t h e r bye-product which was in great d e m a n d for feed- ing live stock. S a r d i n e s have been successfully c a n n e d in India from the early years b u t c a n n i n g Industry suffered s e t b a c k s from time to time d u e to severe technical a n d practical difficulties leading to the closure of the Chalayam cannery in 1 9 3 3 . Though there w a s a rlvlval of the c a n n i n g I n d u s t r y the p r o d u c t s were not so easily sold in International a n d domestic m a r k e t s d u e to the high cost of c a n s (Antony Raja, 1969; Nalr, 1973).

Presently, due to t h e increased d e m a n d for fresh fish from local a n d interior m a r k e t s and easy availability of ice a n d quick t r a n s p o r t facilities, the catch is now c o n s u m e d fresh. But still the fishing i n d u s t r y h a s no infrastruc- t u r e to meet the glut situation t h a t occur at certain times a s h a p p e n e d a t Alleppey district d u r i n g J u l y to September 1999.

Fishery and environmental correlation

The literature is replete with correlation between oil s a r d i n e fishery a n d environmental conditions of t h e Malabar upwelling zone. Hornell (1910), Nalr (1953) a n d Nalr and S u b r a m a n y a n (1955) have related the a b u n d a n c e of oil s a r d i n e to t h e diatom Fragilaria (= Nitzschia) oceantca. The two blooms of this diatom, one at t h e s t a r t of the monsoon a n d the other In September-October coincide with t h e arrival of oil s a r d i n e . Heavy blooms of it were noticed d u r - ing 1949 a n d 1953 when the stock was r e s u s c i t a t i n g after the population c r a s h of the forties. Overfishing a n d growth overfishing a s causative factors for the fluctuation in a b u n d a n c e have been pointed out by S u n d a r a Raj (1934,

1937), D e v a n e s a n (1943) a n d Devanesan a n d C h i d a m b a r a m (1948). Accord- ing to Sam Bennet (1968) a study of the s t r e n g t h of the new year class recruited a n d the s t r e n g t h of the s u b s e q u e n t year class may help In forecast- ing the fishery.

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Marine Fl»herie« Research and Management

T e m p e r a t u r e , salinity and availability of food a s factors controlling oil sardine a b u n d a n c e have also been indicated by Chidambaram (1950), Annigeri (1969), Bensam (1970), C h a n d r a m o h a n and J a m e s (1977), Gopinathan (1974), J a d h a w et al (1989), J a m e s et al (1987), M u k u n d a n (1967), Reghuvendra a n d Reddy (1985). R a m a n a et al (1988), Rao et al (1973) and S u r e s h and Reddy (1980) .The influence of rainfall on oil s a r d i n e h a s been studied by Antony Raja (1972), Murty and Edelman (1971) and K u m a r a n et al (1992).

Murty (1974) h a s suggested the relation of oil s a r d i n e landings to wind drift.

L'onghurst a n d Wooster (1990) have made a detailed study on the short term a n d long term a b u n d a n c e of oil s a r d i n e in relation to the oceanographic and meteorological conditions a n d the upwelllng of the Malabar upwelling zone.

F u r t h e r , they opined t h a t the u n u s u a l l y early remote force upwelling a p p e a r s to inhibit s u b s e q u e n t r e c r u i t m e n t of oil s a r d i n e . Recently M a d h u p r a t a p et al (1992) d i s c u s s e d the influence of various factors of coastal oceanography on oil s a r d i n e fishery. S r i n a t h (1998) m a d e a n exploratory analysis on the pre- dictability of oil s a r d i n e landings in Kerala.

Most of t h e s e s t u d i e s , except a few, were of s h o r t term n a t u r e spread over space and time a n d have neither t a k e n into consideration the p h a s e s of variability in oil s a r d i n e stock nor attempted maximum p a r a m e t e r analyse.

Hence different views have been expressed by m a n y workers.

S u n s p o t a c t i v i t y and oil sardine abundance

The cyclic p a t t e r n in the a b u n d a n c e of oil sardine showed a striking similarity to the eleven year periodicity of the s u n s p o t activity. Comparison of time series d a t a on oil s a r d i n e landings a n d s u n s p o t activity revealed good correspondence. Recently, the s u n spot activity was the lowest during April 1994. It is interesting to note t h a t the catch by all the gears operating along the west coast was either lowest or nil during 1994. Landings on the west coast dipped to 4 0 0 0 t o n n e s in the s a m e year, a major population c r a s h in the recent history. The s u n s p o t activity will be a t its peak by the t u r n of this century when the oilsardine landings may be elevated to a satisfactory level a n d promising t r e n d s are already dlscerable since 1995. The production dur- ing 1997 h a s crossed 2 . 0 0 , 0 0 0 t o n n e s .

S u n being t h e u l t i m a t e source of energy h a s a b e a r i n g on t h e productiv- ity of the environment. It a p p e a r s t h a t the various physical, oceanographlcal, meteorological factors, rainfall, upwelling a n d n u t r i e n t availability are tuned

"278"

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The Indian oil sardine In relation to t h e intensity of s u n s p o t activity. Oil s a r d i n e is an immediate beneficiary of primary production by virtue of its position with a short food chain in the food web. Observations of Hornell (1910), Nair (1953) a n d Nalr and S u b r a m a n y a n (1955) a b o u t the relation between a b u n d a n c e of the fish a n d the d i a t o m s a s s u m e importance in t h i s context. However, lack of time series d a t a on m a n y of the environmental factors is a s t u m b l i n g block in a t t m p t i n g a correlation with t h e fishery for evolving meaningful fishery fore- cast models.

Stock a s s e s s m e n t

Banerji (1973) estimated the total a n n u a l oil s a r d i n e stock a s 4 , 4 0 , 0 0 0 t a n d the average s t a n d i n g crop a s 2 , 1 0 , 0 0 0 t. The corresponding figures a s estimated by S e k h a r a n (1974) were 8,10,000 t a n d 3,90,000 t respectively.

Balan et al; (1979) s t a t e d t h a t the stock level s h o u l d be a b o u t 4 l a k h t o n n e s . This is in agreement with eariier (1972-76) e s t i m a t e s (Anon. 1976). Annigeri et al (1992) e s t i m a t e d t h e MSY as 1,50,000 t a g a i n s t a m e a n b i o m a s s of 1,07,000 t indicating scope for increasing production. Their s t u d i e s indicated t h a t Increasing the fishing effort to the MSY level is not desirable in t h e p r e s e n t fishery a s s u c h a step would decrease considerably the r e t u r n s p e r b o a t to a n uneconomical level. Most of the stock a s s e s s m e n t s t u d i e s a t t e m p t e d in India on a n u m b e r of fishes have always ended u p Issuing t h r e a t e n i n g n o t e s to reduce effort level for avoiding overexploltation. These s t u d i e s have t a k e n Into a c c o u n t t h e total effort In a multlspecies fishery system. Any future s t u d i e s should, therefore, t a k e Into a c c o u n t the effective effort r a t h e r t h a n comput- ing the total effort.

Suggestions for future work

1. S t u d i e s on the indescrlminate d e s t r u c t i o n of juveniles a n d s p a w n e r s , and c o n s e q u e n t depletion of stock.

2. Effect of m e s h size regulations to suggest optimum.

3 . Effort rationalisation of p u r s e seine a n d ring seine. Consideration of effective effort for stock a s s e s s m e n t ,

4. Effect of s e a s o n a l closure of fishing operations.

5. S t u d i e s on fecundity, recruitment, a b u n d a n c e of s p a w n e r s , young fish and s t r e n g t h of the year class.

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Marine Fi»herie» Research and Management

6. A b u n d a n c e of oil s a r d i n e In r e l a t i o n to p r i m a r y p r o d u c t i o n a n d I n t e r - a n n u a l variations in the productivity of the ecosystem.

7. Tagging of oil s a r d i n e from e a s t a n d west coast of India.

8. Stock a s s e s s m e n t of oil s a r d i n e from east coast.

9. Racial investigations u s i n g latest m e t h o d s .

10. Collection of time series oceanographlc d a t a for correlation with the fishery to evolve forecast models.

11. Studies on the effect of global warming a n d rising sea level a n d El Nino. Maximum p a r a m e t e r analyses to develop fishery forecast mod- els.

References

Only the papers published subsequent to " The Indian oil sardine, Sardinella longiceps Valenciennes -An annotated Bibliography" by S.,Girijakumari 11990). CMFRl Special publication 48: 80pp. are listed in the reference.

Annigeri, G; K.Narayana k u r u p , M.Kumaran. Madan Mohan, G.Luther, P.N.Radhakrishnan Nalr. Prathibha Rohit, G.M.Kulkarnl, J.C.Gnanamuthu K.V.Narayana Rao, 1992. Stock assessment of oil sar- dine, Sardinella longiceps Val., off west coast of India. Indian J.Fish., 39 (3 & 4) : 125-135.

Bertalanffy, L. Von. 1938. A quantitative theory of oraganic growth. Human biology;

10(2): 181-213.

Bhattacharya, C.G. 1967. A simple method of resolution of distribution into Gaussian components. Biometrics, 23: 115- 35.

Gnanamuthu, J.C. and V. Thankaraj Subramaniam. 1989. On the emergence of oil sar- dine fishery along the Madras coast. Mar. Fish. In/or. Serv., T&E Ser 96: 6-7.

Kumaran, M., K.V.Narayana Rao, G.G.Annigeri, Madan mohan, P.N.Radhakrishnan Nair, Puthran Prathibha, M.Abdul Nizar, V.K.Janakl and Uma S. Bhat. 1992.

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The Indian oil sardine P r e s e n t s t a t u s of e x p l o i t a t i o n of fish a n d shellfish r e s o u r c e s : Oil sardine.Bu(!. Cent. Mar. Fish. Res. Inst., 4 5 : 92- 110.

Longhurst Alan, R. and W.S Wooster 1990. Abundance of oil sardine Sardinella longiceps) and upwelling on the south west coast of India. Canadian Journal of fisheries and Aquatic Science 4 7 : 2 4 0 7 - 1 9 .

Luther, G. 1994. S t a t u s of sardine fishery at V i s a k h a p a t n a m . Mar. Fish. Infor. Serv. T

& ESer . 1 3 3 : 1-10.

Mahadevan pillai, P.K., M.Radhakrishnan and M. Manivasagam 1992. The oil sardine fishery along northern Tamil Nadu coast with a note on u n u s u a l l y heavy landings at Cuddalore, Pazhayar and Kaveripatnam. Mar. Fish. Infor. Serv.

T&E Ser. 115: 12-14.

Madhuprathap, M., S.R.Shetye. K.N.V.Nair and S.R.Sreekuiharan Nair. 1994. Oil sar- dine and Indian Mackerel: their fishery, problems and coastal oceanog- raphy. Current Science 6 6 (5) : 340-348.

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