Bumper landings of skipjack tuna, Katsuwonus

pelamis was observed at Visakhapatnam Fishing

Harbour on 28th October 2011, wherein about 42 t

were landed by hooks and line

Jaiganesh, P

Rajapackiam, S

Rudramurthy, N

Sethi, S N

CMFRI Digital Repository

Marine Fisheries Information Service T&E Ser., No. 209, 201110First record of  the chimaeroid,  Rhinochimaera atlanticaat Kasimedu Fisheries Harbour, ChennaiS. N. Sethi, S. Rajapackiam, P. Jaiganesh and N. RudhramurthyResearch Centre of CMFRI, ChennaiChimaeras are shark like fishes having large headand elongated body that taper to a whip-like tail. Theycome under the subclass Holocephali, characterisedby the fusion of the upper jaw to the cranium andabsence of scales. Unlike sharks and rays(Elasmobranchii), chimaeras have only 4 pairs ofgill openings which are hidden by a pair of softgill covers, that extend to the base of the pectoral finsand a single external gill opening on each side of thehead (Table 1). On 21-01-2010, a female long nosechimaeroid, Rhinochimaera atlantica,  measuring 150cm and weighing 8 kg was landed at KasimeduFisheries Harbour, Chennai which was caught from adepth of  50-80 m by mechanised gillnet (Fig. 1 and 2).Fig.1. Rhinochimaera atlantica landed at KasimeduFisheries Harbourcurrent pattern was hence in the same direction asthat of wind, as because in the east coast during theonset of winter, the direction of current is fromsouth-east.About 80% of the catch was landed by thenon-motorised sector and the remaining 20% bymotorised crafts. The landings were from three fishingvillages viz., Jalaripeta, Uppada and Bheemunipatnamwith an average catch of 250 kg/craft. Each line oflength  varying from 200 to 300 m was equippedwith 10 to 20 hooks, operated at a depth of 70 to100 m. The other species landed in association withskipjack tuna were yellowfin tuna (Thunnusalbacares), sailfish (Istiophorus platypterus), marlin(Makaira indica), dolphinfish (Coryphaena hippurus),carangids (Caranx sp.) and spotted seer fish(Scomberomorus guttatus) with catches of 2 t,1.75 t, 1.25 t, 0.3 t , 0.075 t and 0.07 t, respectively.The length of K. pelamis landed varied from 440to 650 mm FL with corresponding weight ranging from1333 to 4700 g. Biological investigations revealed thatmajority of the stock were in spent and recovery phase.Catch was auctioned at a price of ` 50-60 /kg to thefish merchants. The sudden reversal in wind directionassociated with the current pattern in the samedirection could have influenced the movement of thespecies which have migrated from offshore tonearshore waters, hence accounting for this suddenincrease in catch. Moreover skipjack tuna is knownto breed in deepsea along the east coast duringJuly - August and then migrate to coastal waters forfeeding during the winter months, which could alsohave contributed to this sudden increase in catch.This is further substantiated by the fact that in majorityof the fishes (55%), the gut was in gorged condition.The catch was negligible during previous couple ofmonths, wherein a total of 5 t were landed togetherfrom mid of August to mid of October. This is thehighest reported landing of skipjack tuna fromVisakhapatnam Fishing Harbour on a single day.Marine Fisheries Information Service T&E Ser., No. 209, 2011 11Total length 150 2nd dorsal inner margin 1Standard length 121 Pelvic fin anterior margin 12Snout to origin of 1st dorsal 71 Pelvic fin posterior margin 6Snout to origin of  pectoral 48 Pelvic fin inner margin 1Snout to origin of anal 110 Anal fin anterior margin 8Snout to origin of head 47 Anal fin posterior margin 6Snout to origin of eye 3.2 Anal fin inner margin 11st dorsal anterior margin 9 Length of upper caudal fin 261st dorsal posterior margin 9 Length of lower caudal fin 331st dorsal inner margin 1 Weight 8 kg2nd dorsal anterior margin 4 Sex F2nd dorsal posterior margin 43Table 1. Morphometric measurements (cm) of Rhinochimaera atlantica landed at Kasimedu Fisheries Harbour, ChennaiThe specimen was a mature female with fournumbers of ripe oocytes, measuring 6 cm in diameter.Stomach was full and contents were in semi-digestedcondition. Other than the report on occurrence of twochimaeroid egg capsules off Tuticorin, Gulf of Mannarfrom commercial deepsea catch at a depth of250-400 m (Arumugam et al., 1990), this is the firstreport on the landing of chimaeroid from south-eastcoast of India.Fig. 2. Digestive system of the female chimaeroid,R. atlantica landed at Kasimedu Fisheries HarbourBopyrid parasite Epipenaeon ingens (Nobili, 1906) (Bopyridae,  Isopoda)infestation in penaeid shrimps of Cuddalore coast, Tamil NaduP. ThirumiluResearch Centre of CMFRI, ChennaiWhile observing the regular landings of penaeidshrimps by mechanised trawlers at CuddaloreFisheries Harbour, species belonging toParapenaeopsis stylifera and Metapenaeopsisstridulans were found infected with the bopyridparasite, Epipenaeon ingens (Nobili, 1906) duringJune, July and November 2010. Details on the extentof parasitic infestation are given in Table 1.In P. stylifera, the percentage of parasitation variedfrom 13.5 to 14.6 in males and 9.7 to 20.8 in femalesduring pre-monsoon months (June-July), while it was68.4 and 26.1 in males and females respectively duringthe monsoon month (November). In M. stridulans, theparasitation ranged from 20 to 41.7% in males and20.8 to 27.5% in females during pre-monsoon monthsand 9.8% in males and 27.4% in females duringNovember.  During the three months of observation,infestation in males of P. stylifera registered 30.2%,when compared to 16.7% in females. However, inM. stridulans, more females were affected (27.4%)as compared to males (19.3%). Earlier records ofpresence of E. ingens in Indian penaeid shrimps arereported in P. stylifera from Malabar coast,Metapenaeopsis stridulans, M. mogiensis, P. styliferaand Parapenaeopsis maxillipedo from Chennai,Penaeus monodon and P. stylifera  from Parangipettai,

First record of the chimaeroid, Rhinochimaera atlantica at Kasimedu Fisheries Harbour, Chennai

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