MATURATION AND SPAWNING OF THE HORSE-MACKEREL, CARANX KALLA (CUV. AND VAL.)

Abstract

The maturity studies of C. kalla were carried out on the material collected from the boat
seine and gill net catches from the inshore waters off Calicut from January 1958 to December
1960. The growth of ova from stage I to II was found to be less than from stages
II to III and the extent of growth from stages II to III and from III to IV was noted to
be almost the same. Growth was maximum between the stages IV and V and minimum
between V and VI. About 50% of the females were found to mature first at about
the size of 124 mm total length. An individual fish was noted to have one short
spawning period but ihe species was found to spawn all round the year with two peaks,
the major one during December-January and the minor one during May-June.
Females appeared in greater proportions in smaller size groups and the males were
dominant in higher siz; groups. The sex ratio in the catch varied widely in the different
months. However, it was nearly 50:50 during the months June, August and October of
some years.
The fecundity was. found to increase with the length of the fish and the number of
ova ranged approximately from 30,000 to 75,000 for the fish lengths 115 mm to 138 mm.
The 'condition factor' was noted to reach the minimum value at a length of 122 mm for
the females and 117 mm for the males when they are considered to mature for the first
time.