Basic HTML Version
International Journal of Marine Science 2014, Vol.4, No.31
http://ijms.biopublisher.ca
1
Research Article Open Access
Age and Growth Based on the Scale Readings of the Two Scarid Species
Hipposcarus harid
and
Chlorurus sordidus
from Hurgada Fishing Area, Red
Sea, Egypt
Sahar F. Mehanna
1,
, Muhammad Abu-Elregal
2
, Yassein A. Abdel Maksoud
1
1. National Institute of Oceanography and Fisheries, Egypt
2. Faculty of Science, Port Said University, Egypt
Corresponding author email
International Journal of Marine Science, 2014, Vol.4, No.31 doi: 10.5376/ijms.2014.04.0031
Received: 17 Feb., 2014
Accepted: 15 Apr., 2014
Published: 11 Jun., 2014
Copyright
©
2014 Mehanna et al., 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:
Mehanna et al., 2014, Age and Growth Based on the Scale Readings of the Two Scarid Species
Hipposcarus harid
and
Chlorurus sordidus
from Hurgada
Fishing Area, Red Sea, Egypt, International Journal of Marine Science, Vol.4, No.31 (doi: 10.5376/ijms.2014.04.0031)
Abstract
The study of age and growth of individuals in a population is fundamental for understanding the general biology of the
species and in particular its population dynamics. Age and growth of two scarid species
Hipposcarus harid
and
Chlorurus sordidus
from Egyptian Red Sea, Hurgada region were studied based on the scale readings using a non-linear back-calculation method. A total
of 1000
H. harid
(17.0 – 50.0 cm TL)
and 700
C. sordidus
(16.0–33.5 cm TL) were aged and their maximum life span was 8 and 5
years respectively. The most dominant age group in the catch is the second age group for
H. harid
(34.7%)
and the fourth one for
C.
sordidus
(45.6%). The von Bertalanffy growth parameters obtained by using the back-calculated lengths were L∞ = 57.16 cm TL,
K= 0.23 year
−1
, and t
0
= −0.65 years for
H. harid
and L∞ = 40.27 cm TL, K= 0.28 year
−1
and t
0
= -0.17 years for
C. sordidus
. These
data are needed to assist in the wise management of this potential fishery. It is also clear that more information about the scarid
biology and dynamics is needed to establish bases for a responsible fishery development of the Egyptian Red Sea.
Keywords
Red Sea; Hurgada; Age; Growth; Scales; Population dynamics; Management
Introduction
Age determination and growth modeling are critical
aspects needed to assess different fish stocks (Hilborn
& Walters, 1992; Dwyer et al., 2003). Assessment of
age and growth is also essential for estimating the
biological and physiological aspects of fishes such as
stock age structure, age-at-50% maturity, yield-
per-recruit and adaptation of stock to changes in
habitat, exploitation and productivity (Morales-Nin,
1992; Francis et al., 1998 & 2000; Campana, 2001;
Welcomme, 2001; Robinson & Motta, 2002;
Kanyerere, 2003; Sulikowski et al., 2007; Simon and
Mazlan, 2010). Also, understanding the life history of
fishes is fundamental for the scientific protection of
fish species and the sustainable use of natural fishery
resources (Jia and Chen 2011; Mehanna, 2013).
The Egyptian Red Sea sector comprises a shoreline of
about 1080 km from Suez in the north to Mersa
Halayab in the south (Mehanna, 1996 & 2011). There
are several fishing grounds along the Egyptian sector
of the Red Sea, with a mean annual catch of about 30
thousand ton (Mehanna, 2005).
Parrot fishes are a group of fishes that have been
traditionally considered a family (Scaridae), but now
they are often considered a subfamily (Scarinae)
within the family Labridae (Bellwood and Schultz,
1991; Choat, et al., 1996 & 2003). Scarids are all
marine species, found in relatively shallow tropical
and subtropical oceans throughout the world, but with
the largest species richness in the Indo-Pacific. There
are about 18 species in the Red Sea (Zootaxa, 2010),
living in the coral reefs, rocky coasts and seagrass
beds, and they play a significant role in the bioerosion
(Bellwood, 1994&1996; Streelman et al., 2002;
Bellwood et al., 2003; Smith et al., 2008). Despite of
the economic importance of scarids, there are no
studies dealing with their biology and population
dynamics in the Egyptian Red Sea. The present paper
is the first to provide growth data of the most common
scarid species in the Egyptian Red Sea sector, Hurgada