PROBLEM OF AGE-DETERMINATION IN THE INDIAN MACKEREL, RASTRELLIGER KANAGURTA, BY MEANS OF SCALES AND OTOLITHS


116 / 71

Authors

  • G Seshappa Central Marine Fisheries Research Institute; Sub-station, Calicut

Abstract

The study of the scales of Rastrelliger kanagurta (Cuvier) collected from different
centres during the period 1955-67 and 1969-70 showed that at all centres specimens below
21 cm in total length were without scale-rings; a small percentage of specimens in the
• 21-22.9 cm group showed rings, while a large percentage among those above 23 cm total
length showed the rings in all the centres, this percentage being the smallest (63.1 %) at
Calicut and largest (94.3%) at Karwar. Two rings occurred frequently in specimens
above 25 cm and up to four rings occurred in the very large specimens of Vizhinjam and
Mandapam, but in these large specimens reading of the rings was difficult as they frequently
became faint and obscured as a result of the thickening of the scales subsequent
to the ring-formation. The scale-rings seem to be formed as a result of a physiological
strain on the fish during the process of growth and ripening of the gonads and also spawning.
When clear rings were not noticed in mackerel with gonads in advanced stages,
there were thin margins, which indicated the beginning of ring formation. The otoliths
did not show any annuli that could be used for age-determination

Downloads

Download data is not yet available.

Author Biography

  • G Seshappa, Central Marine Fisheries Research Institute; Sub-station, Calicut
    Central Marine Fisheries Research Institute; Sub-station, Calicut

Downloads

Issue

Vol. 16 No. 1 & 2 (1969)

Section

Articles

License

The copyright of the articles published in Indian Journal of Fisheries vests with the Indian Council of Agricultural Research, who has the right to enter into any agreement with any organization in India or abroad engaged in reprography, photocopying, storage and dissemination of information contained in these journals. The Council has no objection in using the material, provided the information is being utilized for academic purpose but not for commercial use. Due credit line should be given to the ICAR where information will be utilized.

How to Cite

Seshappa, G. (2011). PROBLEM OF AGE-DETERMINATION IN THE INDIAN MACKEREL, RASTRELLIGER KANAGURTA, BY MEANS OF SCALES AND OTOLITHS. Indian Journal of Fisheries, 16(1 & 2), 14-28. https://epubs.icar.org.in/index.php/IJF/article/view/13235