Thiruvengadam Vaitheeswaran , V.K. Venkataramani

1 Tilapia Project-Hatchery Technical and Head Victoria Treasures Limited, Bugabo Bay Garuga on Victoria Lake, Kampala, Uganda, East Africa
2 Former Dean, Fisheries College and Research Institute, Tamil Nadu Fisheries University, Tamil Nadu, India
Author    Correspondence author
International Journal of Aquaculture, 2017, Vol. 7, No. 24   doi: 10.5376/ija.2017.07.0024
Received: 17 Nov., 2017    Accepted: 20 Dec., 2017    Published: 29 Dec., 2017

This is an open access article published under the terms of the Creative Commons Attribution License, which permits unrestricted use, distribution, and reproduction in any medium, provided the original work is properly cited.

Vaitheeswaran T., and Venkataramani V.K., 2017, Stock assessment of heavybeak parrotfish Scarus gibbus (Ruppell, 1829) (Family: Scaridae) off Tuticorin coast, India (08°53.6’N, 78°16’E and 08°53.8’N, 78°32’E) - 36M, International Journal of Aquaculture, 7(24): 159-165 (doi: 10.5376/ija.2017.07.0024)

The commercial important coral reef fishes viable source, re-aggregating, have been exploited coral reef parrot fish in pears coast of Gulf of Mannar. Its beautifully colour parrot fish reported between ranges 08°53.6’N, 78°16’E and 08°53.8’N, 78°32’E at a depth of 36 m. The parrot fishing of natural mortality (M), fishing mortality (F) and total mortality (Z) was calculated at 0.47, 0.40 and 0.87, respectively. Growth equation based on modified von Bertalanffy’s equation and Ford-Walford graph was arrived. The growth parameters such as L∞ = 104.50 cm and K = 0.23 was estimated combining both sexes. Length and weight frequency data obtained from the growth equation, has been dealing with S. gibbus attains the length of 21.96, 39.21, 51.76, 62.74, 70.58, 77.64 and 83.13 mm during first and seventh year respectively. The spawning peaks one in December and another in April could be observed. The life span of S. gibbus was estimated for seven years. The exploitation ratio of 0.46 indicated that the resource of S. gibbus is currently exploited along the Tuticorin coast. Heavy fishing pressure on the length group 6 to 81 cm revealed that S. gibbus in Tuticorin waters suffer due to recruitment overfishing. The present level of exploitation rate and exploitation ratio (F/Z) is estimated at 0.46 and 0.5 respectively. The average length of parrot fish, the beginning capture (Lc) was calculated as 20.0 cm. The total stock, average annual stock and maximum sustainable yield were estimated as 35.150 tonnes, 9.385 tonnes and 10.206 tonnes respectively. Virtual Population Analysis have been assessing the mortality ranges from 85 cm. The parrot fish study shows that the further stressed that strict management measures need to be undertaken to conserve this species from further to avoid exploitation and to restore the biodiversity of heavybeak parrotfish population of Gulf of Mannar in general and Tuticorin coast in particular.

Scarus gibbus; Population dynamics; Age and growth; Thoothukudi coast; Recruitment pattern; India