Ramalingaiah, D (MAJOR)Suguna, TRavindra Kumar Reddy, DLAVANYA, D2021-07-142021-07-142017-05https://krishikosh.egranth.ac.in/handle/1/5810170505THESESThe flathead grey mullet, Mugil cephalus fishery supports the livelihood of the fishermen along Krishnapatnam and Mypadu coasts. In the present study, Morphometric and Meristic characteristics, Length-Weight relationship, Food and feeding, Reproductive biology, Age and Growth and Mortality parameters were studied. The maximum length of Mugil cephalus examined was found to be 32 cm and 36 cm from Krishnapatnam and Mypadu coasts respectively. The observed ‘b’ values in Krishnapatnam (male = 3.093, female = 3.023, pooled = 3.288) indicates that growth was isometric in male and female population, where the value of b can be approximated to 3. Growth in pooled population indicates the allometric growth pattern (b=3.288). In Mypadu coast, the ‘b’ values (male = 2.99, female = 3.32, pooled = 3.0944) showed that the growth is positive allometry for females and isometric growth for males and pooled population, where b value can be approximated to 3.0. Mugil cephalus found to be omnivorous, preferring mainly on Diatoms. The length at first maturity was observed to be 219.5 mm. Fecundity estimates ranged from 88,998 – 3,01,142 eggs in Kp coast and 86,568 - 3,24,148 eggs in Mypadu coast. Age at zero length (t0) calculated as - 0.4589 year and - 0.3447 year for the fishes collected from Krishnapatnam and Mypadu coasts. Growth parameters such as asymptotic length “L” and growth co-efficient “K” were estimated to be 35.839 cm and 0.7391 yr -1 from Krishnapatnam coast and 41.4891 cm and 0.54203 yr -1 from Mypadu coast. The total mortality (Z), natural mortality (M) and fishing mortality (F) calculated from Krishnapatnam coast were 1.4949, 1.3644 and 0.1305 and Mypadu coast were 2.2245, 1.0732 and 1.1512 respectively. This study indicates that fishing operations can be increased in Krishnapatnam coast. Regulation of mesh sizes for fishing gear in both the coasts will help in improving the fish to breed before being caught.EnglishThesis