GOVERNMENT OF INDIA FISHERY SURVEY OF INDIA Department of Fisheries
Ministry of Fisheries, Animal Husbandry and Dairying

DECADAL OBSERVATIONS ON EXPLORATORY SURVEYS OF OCEANIC TUNA AND ALLIED RESOURCES IN THE INDIAN EXCLUSIVE ECONOMIC ZONE (EEZ

L.RAMALINGUM, VINOD KUMAR MUDUMALA, SIJO P VARGHESE, S.RAMACHANDRAN, P.PAUL PANDIUN, KIRAN S MALI, A.SIVA, A.TIBURTIUS, S.K.DWIVEDI, ASHOK S. KADAM, A.R.KAR, N.UNNIKRISHNAN, A.J.CHEMBIAN, J.C.DHAS, AMOD TAMHANE, RAHUL KUMAR TAILOR, SWAPNIL SHRIKE, RAJASHR

DECADAL OBSERVATIONS ON EXPLORATORY SURVEYS OF OCEANIC TUNA AND ALLIED RESOURCES IN THE INDIAN  EXCLUSIVE ECONOMIC ZONE (EEZ)

Demersal fishery resources off the west coast of India – an update

Premchand, Kiran S. Mali, A. Tiburtius, Sijo P. Varghese, L. Ramalingam, S. K. Dwivedi and D. E. Uikey

Demersal fishery resources off the west coast of India – an update

Demersal fishery resources off the east coast of India- an update

PREMCHAND, KIRAN S. MALI, A. TIBURTIUS, SIJO P. VARGHESE, A. K. BHARGAVA AND RAHULKUMAR B. TAILOR

Demersal fishery resources off the east coast of India- an update

Depredation in the Longline fishery of the Indian waters

S. Varghese, V.S. Somvanshi and Sijo P. Varghese

Depredation of fishes caught on the pelagic long line gears is a global phenomenon calling attention of the Scientists and the fishermen community to address the issues related to it at national and global level. The depredation data collected during the survey cruises of the tuna long line vessels of the Fishery Survey of India during the period 2000-06, were analysed and the area-wise depredation rate in the three regions of the EEZ, the Arabian Sea, Andaman and Nicobar waters and East Coast, in respect of the depredated cruises, depredated sets and for the entire operation is calculated and presented. The depredation rate calculated for the depredated cruises for the Indian EEZ is 2.76% (by number of fishes) and the value in relation to the predated sets is found to be about 16.23% (by number). No specific trend in depredation is observed during different years and months as the index was of varying nature. The depredation rate is also not found to have any direct relevance to the gear type, i.e., monofilament or multifilament gear. The most affected species are the tunas, swordfishes, sailfishes and seer fishes. Almost all species hooked on the lines were found to be subjected to depredation, but in varying proportion. The depredation therefore does not appear to be species-specific or time-specific either. Among the three different regions, the depredation rate is found to be higher in Andaman and Nicobar waters for the depredated cruises (2.99%), followed by Arabian Sea (2.57%) and Bay of Bengal (2.08%). Similarly the index for the depredated sets was found to be 17.06% for Andaman and Nicobar waters, 14.15% for the Arabian Sea and 12.5% for Bay of Bengal.

Introduction of Monofilament Longline technology for harvesting oceanic tuna and allied resources in the Indian EEZ

V.S. Somvanshi, S. Varghese and Sijo P. Varghese

Exploration of deep seas for locating and prospecting new resources, by introduction of new technologies, helps the coastal nations in enhancing their fish production. With the objective of introducing and popularising monofilament longlining technology in the Indian waters and training the Indian fishermen in this specialised fishing technique, the FSI has acquired two monofilament long liners named Matsya Vrushti and Matsya Drushti which are deployed for survey in Arabian Sea along the West coast and in Bay of Bengal and Andaman and Nicobar waters along the East Coast, within the Indian EEZ respectively. In order to evaluate efficiency of the modern monofilament gear with reference to that of the conventional multifilament gear a comparison of the two gears during the above period is attempted in this Bulletin. Besides providing spatio-temporal variations, an attempt has been made to present information on size and weight of individuals of each species with regard to the monofilament caught vis-à-vis conventional multifilament hooked individuals. The results of monofilament long line survey conducted in the Arabian Sea along West coast during 2005-07 registered an aggregate HR of 1.01% for all fish and 0.37% HR for yellowfin tuna, where 40% of the total catch consisted of this species. The spatial distribution of tunas and allied species has shown a higher hooking rate in latitudes beyond 18oN. The area 22-67 of lat. 22oN recorded a very high HR of 10.5% for all fishes and 10.4% for YFT alone. The seasonality of yellowfin tuna along this coast is observed to be from April-December, the peak months being April, May and August. The surveys along East coast (Bay of Bengal) yielded a HR of 1.01% for all fishes during 2005-06 and 0.85% during 2006-07. The average HR for YFT was 0.41%, and 51.5% of the catch was constituted by tunas. The seasonal variation in the HR show that the period June to December is good season for tuna fishing along the East Coast. The spatial distribution of yellowfin tunas along the East coast has indicated that some of the areas of high HR for YFT are 13-80 (0.9%), 15-82 (0.71%), 16-82, 16-83 (1.2% each) and 17-83 (0.88%). Both the vessels together achieved an average hooking rate of 0.93% during the two year period in the Indian EEZ. A comparison of the results of operation of the multifilament long lining undertaken by the two vessels Yellow Fin in the Arabian Sea and Blue Marlin in the Bay of Bengal show that the hooking rate obtained in monofilament longlining was higher. An increase in the aggregate HR in general and for the tunas in particular with a significant reduction in the HR of sharks was noticed during the monofilament operations. However the proportion of very large size fish was noticed to be higher in the multifilament gear which could be attributed to the deeper depth, these gear occupy and the behavioural tendency of large fish to swim to deeper depths.

Fishery Resources of the Indian EEZ around Andaman and Nicobar Islands

M.E. John, A.K. Bhargava, S. Varghese, D.K. Gulati, Ashok S. Kadam and S.K. Dwivedi

The Andaman and Nicobar Islands are located in the southern Bay of Bengal between latitude 6°45' N and 13°41' N and longitude 92°12' E and 93°57' E. The total coastline length is 1962 km, which is about one fourth of the coastline of India. The Exclusive Economic Zone around the islands encompasses an area of 0.6 million km2 forming about 30 percent of the Indian EEZ.

Fisheries form one of the major natural resources of the islands. Over 1200 species of fishes are known to occur in the island waters.

Though a number of development schemes had been proposed by various expert groups and task forces in the past. Concreted efforts are yet to be made and the fishery resources in the Andaman and Nicobar waters by and large remain under exploited.

Fishery Survey of India had carried out exploratory survey of demersal, neritic, pelagic and oceanic resources in the Andaman and Nicobar water by diversified methods. The surveys during the past three decades have provided very valuable information on the composition and magnitude of harvestable resources in the EEZ around the island groups.

This Bulletin provides updated information on the marine fishery resources in Andaman and Nicobar waters based on resources surveys carried out so far. The resource potential is reassessed and developmental prospects are also discussed.

Oceanic tuna resources in the North-West region of Indian EEZ

K. Govindaraj, M.E. John, Premchand, N. Unnikrishnan, Jocab Thomas and V.S. Somvanshi

Oceanic tunas and allied stocks form a major resources base for augmenting marine fish production from the Indian EES. In order to generate a sound information base to facilitate utilisation of these resources, Fishery Survey of India has been conducting survey of the deep swimming larger pelagics by tuna longlining. This bulletin contains the results of survey undertaken on board the vessel Yellow Fin along the north-west coast of India during 1996-98.

Contributions To Fishery Biology In Indian Seas

V.S.SOMVANSHI AND M.E. JOHN (EDS.)

PAPER 1. STUDIES ON SOME BIOLOGICAL ASPECTS OF STRIPED GOAT FISH UPENEUS VITTATUS (FORSKAL) FROM NORTH-EAST COAST OF INDIA

D.M.ALI AND K. GOPALAKRISHNAN

This paper presents some aspects on the biology of Upeneus vittatus from the north-east coast. The von Bertalanffy growth parameters are derived as Loo = 214 mm, K = 0.63 and t= -0.05. The mortality coefficients obtained are Z = 3.6 and M = 0.8. Sex ratio indicates predominance of females. The length-weight relationships worked out are :

Males Log W = -4.7983 + 3.2071 Log L

Females Log W = -5.4934 + 3.4285 Log L

PAPER 2. SOME OBSERVATIONS ON THE LENGTH-WEIGHT RELATIONSHIP, SIZE DISTRIBUTION AND SEX RATIO OF DEEP SEA LOBSTER, PUERULUS SEWELLI (RAMADAN)

P.PAUL PANDIAN AND G.K. AVHAD

The length-weight relationship, size distribution and sex ratio of the deep sea spiny lobster. Puerulus sewelli from the south-west coast were investigated. The length and weight measurements were found to be best fitted by the equation W = aLb and the relationships derived are as follows :

Male W = 0.0103 L2.9625 Female W = 0.0107 L2.9402 Combined W = 0.0101 L2.9702

The size of the lobster ranged from 104 to 192 mm in total length. The female to male ratio was 1:1.29.

PAPER 3. FOOD AND FEEDING HABITS OF PRIACANTHUS HAMRUR (FORSKAL) FROM THE UPPER EAST COAST OF INDIA

K.P.PHILIP

A study of the food and feeding habits of Priacanthus hamrur from the upper east coast of India revealed that it is a carnivorous species feeding on crustaceans and teleost fishes. About 60 percent of the identifiable food items was constituted by crustaceans like alima, squilla,crabs, prawns and euphausiids. Bregmaceros spp. and eel were the dominant teleost fishes. Seasonality in the abundance of food components was studied. Diversity of food was less in fishes from deeper waters. Young fishes showed a marked preference to small crustaceans. Feeding intensity was high during January to June and low during July to December. Condition factor showed good relation with the feeding intensity than maturation. A comparative study of the food items of P.hamrur and Nemipterus japonicus showed a good degree of overlap in the food items.

PAPER 4. STUDIES ON FOOD AND FEEDING HABITS OF UPENEUS MOLUCCENSIS ALONG NORTH-WEST COAST OF INDIA

A.K.BHARGAVA AND V.S. SOMVANSHI

Goat fishes of the family Mullidae are of economic importance and form a minor fishery along Indian coast. Upeneus moluccensis is the dominant species among red mullets occurring along the north-west coast. The study on food and feeding habits indicates that shrimp forms the main food of U. moluccensis. The younger specimen consumes juvenile fishes and crabs also. The fishes above 14 cm length feed actively when compared to the smaller specimen.

PAPER 5. MATURITY AND SPAWNING OF THE CAT FISHARIUS THALASSINUS (RUPPELL) OFF THE NORTH-WEST COAST OF INDIA

MANALI A. PARAB

The maturity cycle of Arius thalassinus is described. The ripeova measure 15-18 mm in diameter, size at first maturity is 36.0 cm. The fish breeds once a year during April to August. The females are predominant with a male to female ratio of 1:1.23. Fecundity varies between 34 and 88 ova per female. Parental care is exhibited by males.

PAPER 6. SOME ASPECTS ON THE REPRODUCTIVE BIOLOGY OF YELLOWFIN TUNA THUNNUS ALBACARES IN THE BAY OF BENGAL

M.E.JOHN, M.NEELAKANDAN, V.SIVAJI, B.PREMCHAND, P.S. PARASURAMAN, M.K.SAJEEVAN AND P.SIVARAJ

Some aspects on reproductive biology of yellowfin tuna obtained in longline gear from the Bay of Bengal are discussed. Males are predominant with a sex ratio of 2.45:1. In larger fish above 140 cm length the male dominance increases drastically and above 160 cm length all fish are males. The trend in sex ratio was consistent in all seasons with significant level of chi-square values. The maturity cycle, studied with reference to gonad index and group maturity index, indicates that the species spawns mainly during November to April. Comparison is made with the spawning season of the species reported from different regions of Indo-Pacific Ocean.

PAPER 7. LENGTH-WEIGHT RELATIONSHIP OF PRIACANTHUS HAMRUR OCCURRING ALONG THE NORTH WESTERN INDIAN EEZ

S.VARGHESE

Length-weight relationship of Priacanthus hamrur from the north-west coast of India is estimated. The result obtained shows that value of the exponent `b' is 2.6285 for males, 2.8803 for females and 2.7810 for both sexes combined. The growth of the species is allomet ric. The resutls are compared with the length-weight relationship of different species of Priacanthids occurring in the south-east Asian waters.

PAPER 8. PRELIMINARY STUDIES ON BIOLOGY OF ACROPOMA JAPONICUM (GUNTHER 1859) : (PISCES, PERCIFORMES, ACROPOMATIDAE)

S.K.NAIK AND D.E.UIKEY

Acropomatids are deepsea fishes sometimes found in the demersal catches beyond 100 m depth along continental shelf. Acropoma japonicum caught from the central west coast of India during March-April 1996 has been used for this study.The specimens were found in size range of 9.6-14.0 cm weighing 8-34 gm. The length-weight relationship is W = 0.020416 L2.748689. The sex ratio 1:5.43, was observed to be significantly different (X2 = 64.066 : 0.05 : df = 133) in favour of females. Males dominated among smaller individuals and females in the larger size groups. The fecundity ranged from 471 to 5331 eggs with an average of 208 eggs per gram body weight. Small prawns are the main food item of these fishes.

PAPER 9. OBSERVATIONS ON MATURITY AND SPAWNING IN INDIAN SCAD, DECAPTERUS RUSSELLI (RUPPELL, 1830) ALONG NORTH-WEST COAST OF INDIA

A.V.TAMHANE AND V.S. SOMVANSHI

Indian scad Decapterus russelli belonging to family carangidae is a commercially important fish. It breeds once in a year with a prolonged spawning season. Spawning season starts in June and continues upto December. Minimum size at first maturity determined is 13.5 cm. The sex ratio (M:F) for the entire period of study is 1:1.2. The females were found to be dominant during the study period.

Marine Fisheries Resources Off Gujarat Coast

A.K.BHARGAVA, S. VARGHESE, V.V.NAIK AND M.E.JOHN

Among the maritime states of India, Gujarat has longest coastline and widest shelf area. Coastal upwelling during south-west monsoon and the heavy run off from Sabarmati, Tapti and Narmada rivers cause enrichment of inshore areas which sustain some of the major commercial fisheries in the region. This Bulletin presents an account of the marine fishery resources survey conducted along Gujarat coast (lat. 20N to 23N) upto 1992 by different types of vessels and gear. Northern areas off Dwarka and Kutch were the most productive areas comparable with richest fishing grounds of the world. Demersal resources survey carried out by M.T. Murena during 1977, Matsya Nireekshani during 1979-80 and 1991-92, Matsya Varshini during 1979-80 and Matsya Mohini during 1986-92 showed that Gujarat coast has potential for Sharks, catfishes, perches, pomfrets, sciaenids, polynemids, seer fishes, clupeids, squids and cuttle fishes. Estimation of biomass and stock density showed that highest density of 11.3 tonnes/sq.km was observed within the same depth in lat. 23N. 67% of the total biomass estimated was in the inshore waters upto depth of 50 m. Maximum sustainable yield 81.6% was noticed in 0-50m depth and this shows that Gujarat coast is fertile for exploitation of pelagic and demersal resources.

Fishery Resources Of Lakshadweep

P.SIVARAJ, M.E. JOHN AND T.E. SIVAPRAKASAM

The Union Territory of Lakshadweep comprises a cluster of 10 inhabited islands and 17 uninhabited islands with a total land area of 28.5 sq.km. between lat. 8 and 1230'N and long. 71 and 74E. The annual marine fish production in the islands fluctuated between 2896 tonnes to 7298 tonnes during 1979-88 period with average of 4820 tonnes. Pole and line is the predominant fishing method and skipjack tuna is the major component of the catch. The FSI has done extensive tuna longline survey in the Lakshadweep sea from the vessel Matsya Sugundhi during 1983-88. Highhooking rate of yellowfin tuna has been reported. Areawise and season wise results of the survey are presented. The trawl survey vessel Matsya Varshini conducted bottom trawling in the Basses de Pedro Bank, and the results are discussed in the Bulletin. Besides finfishes, the archipelago is endowed with resources like sea cucumber and octopus. On future prospects of developing fisheries, it is emphasized that the unexploited tuna resources should be exploited by commercial operation, employing large purse-seiners, pole and line and longline vessels.