Reproductive biology of Sciaenid fish, Johnieops osseus (Day), from the South Kanara coast

Though some informalion is available regarding the breeding habits and early life histories of sciaenids'-s detailed studies on reproductive biology are lacking. The present paper deals with the reproductive biology of Johtlieops osseus, the dominant species of the sciaenids captured off South Kanara Coast

Ovary as an indicator of frequency of spawning in fishes

In majority of the marine fishes from tropical areas, maturation is a continuous process resulting in the occurrence of mature fishes throughout the year. In several Indian marine fishes, because of multiple spawning, a truly spent fish is scarcely found and also difficult to identify. Instead, partially spent fishes have been reported in a number of cases. As the eggs contained in the ovary are progressively ripened and shed, the ovary itself grows smaller, and to the naked eye, seems to reverse the stages by which it attained fuji maturity. The ovaries of such fi shes, though superficially resemble the normal stages III to V, differ from them in macroscopic appearance as well as microscopic structure to some extent. It occurred to the authors that such partially spent ovaries of fishes yield clues to the frequency or spawning in different species. In the present paper, the occurrence and nature of such ovaries and their relation to the frequency of spawning in two species of ribbon-fishes and a sciaenid have been discussed with supporting evidence from data on other fishes

Albino of the marine cat fish, Tachysurus tenuispini(Day)

A specimen of the marine cat fish, Tachysurus tenuispinis exhibiting complete albinism caught in a trawl net operated at night at a depth of about 25 m was collected at the Malpe fish Ianding centre on 10-2-197

Length-weight relationship and condition factor of the Sciaenid fish, Johnieops osseus (Day)

Length-weight relationship of J. osseus indicated an allometric form of growth. Seasonal variations in the condition offish could not be attributed to any particular facto

Fishery and bionomics of sciaenids of South Kanara

Sciaenids, popularly known is jew fish, croakers or drums are one of the commercially important groups of marine fishes of India. They rank very high in abundance forming on an average, 7,04 % of the tora-f{.p1arine fish catch of the country (1974-76)

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Not AvailableSciaenids, popularly known is jew fish, croakers or drums are one of the commercially important groups of marine fishes of India. They rank very high in abundance forming on an average, 7,04 % of the tora-f.p1arine fish catch of the country (1974 -76).Not Availabl

Reproductive Biology of Sciaenid Fish, Johnieops osseus (Day), from the South Kanara Coast

19-24J. osseus spawns throughout the year, releasing 3 batches of eggs in a year. Size at first maturity is 12 cm and fecundity about 46000 eggs per individual fish. Females outnumber males in commercial catches, although the sex-ratio shows no significant deviation

Instance of unusual structure of a scale of the sciaenid fish, Johnieops osseus (Day, 1876)

During the course of observations on the growth checks in the scales of the sciaenid fish, Johzzieops ossezrs (Day), one ctenoid scale which markedly differed in structure from all the other scales was encountered in a female specimen, 160 mm in length. The scale was taken from the seventh row below the lateral line in the middle region of the body

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Not AvailableLength-weight relationship of J. osseus indicated an allometric form of growth. Seasonal variations in the condition offish could not be attributed to any particular factorNot Availabl

Length-Weight Relationship and condition Factor of the Sciaenid Fish, Johnieops osseus (Day)

67-68Length-weight relationship of Johnieops osseus indicated an allometric form of growth. Seasonal variations in the condition of fish could not be attributed to any particular factor