COBIA (Rachycentron canadum)

Seafood containing heavy metals as a result of environmental contamination causes toxicity inhuman beings. To evaluate such kind of contamination, our study targeted the analysis of metalssuch as lead, copper, cadmium, mercury, and arsenic in muscle tissue of the fish. The fishcommonly consumed such as Brama brama (Pomfret), Rachycentron canadus (Surmai/King Fish),Rastrelliger kanagurta (Mackerel), Eleutheronema tetradactylum (Ravas/Indian salmon), andMetapenaeus monoceros (Brown Prawn) were collected from four different docks in the city. Theheavy metals in tissue samples of fish were estimated using voltammeter and cold vapor atomicabsorption spectrophotometer. Heavy metal concentration in the tissues varied significantlydepending upon the locations from where the fish were collected. Although the concentration ofarsenic, copper, cadmium, and lead were in normal range, the concentration of mercury was foundto exceed the daily permissible levels (1kg/g) as a food source for human consumption. We haveanalyzed heavy metals from different locations in Mumbai-Versova dock, Sassoon dock, NaviMumbai dock, and Mazgaon dock.20. Dhawan, R.M., Namboothiri, P.V.S. & Gopinathan, V.G. (1969). Results of trolling lineoperations in Goa waters during 1965-68. Indian Journal of Fisheries, 16(1-2), 181-187.The results of trolling line operations conducted for the first time in Goa waters by the Directorateof Fisheries, Panaji, during the yrs 1956-68 have been discussed. These operations, in later years,led to starting of a small commercial fishery. The trolling line catches are constituted byScomberomorus commerson, Chorinemus lysan, Caranx sansun, Sphyraena sp, Chirocentrusdorab, Rachycentron canadus, Euthynnus affinis and Thynnus macropterus. The size groups,gonadal condition and food of Scomberomorus commerson and Chorinemus lysan which were the 2main spp in the fishery have been described.21. Ditty, J.G. (2001). Preliminary guide to the identification of the early life history stages ofRachycentrid fishes of the Western Central Atlantic. NOAA Technical Memorandum NMFSSEFSC, 460 (12).The family Rachycentridae, contains a single cosmopolitan species, Rachycentron canadum, foundprimarily in tropical and subtropical waters, except those of the eastern Pacific (Briggs 1960).Cobia are a highly prized recreational species that are also taken incidently in commercial fisheries.In the western Atlantic, cobia fish occurs from Massachusetts to Argentina but are most commonalong the U.S. Atlantic and Gulf coasts. Cobia are usually absent from northern Gulf of Mexico andtemperate Atlantic waters along the U.S. coast during late fall and winter when they are found offthe Florida Keys. Cobia migrates north along the Atlantic and Gulf coasts during spring,reappearing in the northern Gulf during March and April. Cobia is taken off Louisiana and Texasassociated with oil and gas platforms or rafts of Sargassum.22. Ditty, J.G. & Shaw, R.F. (1992). Larval development, distribution, and ecology of cobiaRachycentron canadum (family: Rachycentridae) in the northern Gulf of Mexico. Fishery Bulleting,90(4), 668-677.Cobia (Rachycentron canadum) is a highly prized recreational species of worldwide distribution intropical and subtropical seas, but the development, distribution, and ecology of its early life stagesare poorly known. Eggs are spherical, average 1.24 mm in diameter, and have a single oil globule(mean diameter 0.45 mm). The perivitelline space is narrow and the embryo heavily pigmented.Eggs hatch in about 24 h at 29 °C based on the relationship between egg diameter and watertemperature to predict development time in other marine fishes. Larvae hatch at about 2.5 mmSL.Cobia spawns in both estuarine and shelf waters during the day, and eggs and larvae are usuallycollected in the upper meter of the water column. Larvae are recognized by the large supraorbitalridge with a single spine, laterally swollen pterotics, heavy body pigmentation, minute epithelialspicules covering the body integument, and a pair of moderate-to-large, simple spines on either sideof the angle of the posterior preoperculum. Only 70 larvae < 20 mmSL were collected andidentified from the Gulf of Mexico between 1967 and 1988; most occurred between June andSeptember at surface temperatures greater than or equal to 25 °C, salinities > 27 ppt, and within the100 m depth contour. Similar patterns of head spination provide evidence of a sister-grouprelationship between cobia (Rachycentron canadum) and dolphinfish rather than that previouslyhypothesized between cobia and remoras.23. Dung, L.Q. & Cu, N.D. (2008). Partial chronic toxicity test of copper (Cu), zinc (Zn), and cyanide(Cn) for young cobia fish (Rachycentron canadum). Marine Research in Indonesia, 33(1), 49-53.6