International Journal of Aquaculture, 2017, Vol.7, No.24, 159-165
159
Research Report Open Access
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
Thiruvengadam Vaitheeswaran
1
, V. K. Venkataramani
2
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
Corresponding author Email
International Journal of Aquaculture, 2017, Vol. 7, No.24 doi
Received: 17 Nov., 2017
Accepted: 20 Dec., 2017
Published: 29 Dec., 2017
Copyright © 2017
Vaitheeswaran and Venkataramani, 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.
Preferred citation for this article
:
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
Abstract
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.
Keywords
Scarus gibbus
; Population dynamics; Age and growth; Thoothukudi coast; Recruitment pattern; India
1 Background
The nest building of parrotfish is always a unique group of parrot fish (Family: Scaridae) in pearl coast of India.
Parrot fish have been found in tropical, sub-tropical, Indo-Pacific, partial temperate countries and Indian Oceans,
its habitat only for coral associate fishes, have been reported that the herbivorous food and feeding habit.
Streelman and Alfaro (2002) have been reported that the 90 species of parrotfish in the group of (Family:
Scaridae). Randall (1974) has been revealed that the parrot fish feeds on coral polyps and algae. Study revealed
that the marine ornamental fish has been reported in the Gulf of Mannar, 113 species of fish from 24 families
(Venkataramani et al., 2005). Tamil Nadu ranks 5th in total fish production of the country and the total fish
production of the Tamil Nadu State during 2014-15 were 6.97 lakhs tonnes. The export of marine products of
93,477 MT and earned a foreign exchange of Rs. 5,308.17 crores during 2014-15 (Rupees). The fisheries sector of
Tamil Nadu has contributed 0.7 percent of the total Gross State Domestic Product (GSDP) of the State (Policy
note, 2015-2016). The present investigation, to estimate asymptotic length (L∞), growth coefficient (K), natural
mortality (M), fishing mortality (F), total mortality (Z), exploitation ratio (E) and recruitment pattern (Lc/L∞);
where Lc is length at first capture) and M/K and length-weight relationship of
S. gibbus
off Tuticorin coast of Gulf
of Mannar, India.
