International Journal of Marine Science 2015, Vol.5, No.30, 1-5
2
length-weight relationship have been studied for
various fishes like
Siganus canaliculatus
from Gulf of
Mannar (Jayasankar, 1990; Anand and Sita Rami
Reddy, 2012),
Sillago sihama
from Mandapam region
(Jayasankar, 1991),
Sphyraena obtusata
from Bombay
waters (Jaiswar et al. 2004), marine ornamental fish
(Murty, 2002)
Scarus ghobban
from Lakshadweep
(Molly Varghese et al. 2009),
Trachinocephalus myops
from Chennai (Shoba
and
Gomathy, 2007),
Lethrinus
lentjan
and
Lethrinus nebulosus
in thoothukudi coast
(Vasantharajan et al., 2013),
Myripristis murdjan
in
Cuddalore coast (Anbalagan et al., 2009),
Upeneus
vittatus
off Visakhapatnam (Rajkumar, 2004),
Scatophagus argus
(Gandhi et al. 2013). But in
Cuddalore coast the length weight relationship of reef
associated fishes is very scarce. Hence the present
study will provide further contribution to the available
length-weight relationships for most of the
commercially exploited coral reef associated fishes of
Cuddalore, southeast coast of India.
1 Materials and Methods
Ten species of coral reef associated fishes were
collected from Cuddalore landing centre (11º42΄ N;
74º 46΄E), southeast coast of India (Figure 1).
Cuddalore is one of the important fish landing centres
of Tamil Nadu having a coastline of 11km. The river
Pennaiyar, Paravanar, Uppanar and Gadilam merge
with Bay of Bengal near Cuddalore forming a vibrant
estuarine system before discharge into the sea. The
fishing harbour is located near the mouth of Uppanar
estuary. Fishes were identified using standard fish
identification manuals (Day, 1878; Fischer and Bianchi,
Figure 1 Study area map showing the location where collection
was made
1984; Talwar and Jhingran, 1991; Froese and Pauly,
2015). The total length was measured to the nearest
cm using a measuring board and the total weight was
measured to the nearest g using an electronic balance.
The LWR was calculated employing Le Cren’s (1951)
formula,
W= a.L
b
and its logarithmic form: log W = log a + b log L as
followed by Ramasesaiah and Murty (1997). Where
W is the total weight, L is the total length, “a” is the
intercept, and “b” is the slope. Length-weight
relationships may help determine whether somatic
growth is isometric (b=3) or allometric (negative if
b<3 or positive if b>3) (Ricker, 1973; Spiegel, 1991).
The degree of association between the variables was
computed by the determination of the regression
coefficient (r
2
) and statistical significance level of r
2
and 95% confidence limits of parameters a and b were
estimated
(Santos et al., 2002).
2 Result
In the present study length weight relationships of ten
species of coral reef associated fishes (
Siganus
canaliculatus
,
Siganus javus, Trachinocephalus myops
,
Lutjanus fulviflamma
,
Lutjanus russellii
,
Acanthurus
tristis
,
Upeneus vittatus
,
Scolopsis vosmeri
,
Scatophagus argus
and
Epinephelus coioides
were
analysed. Totally 1263 individuals belonging to eight
families (Siganidae, Synodontidae, Lutjanidae,
Acanthuridae, Mullidae, Nemipteridae, Scatophagidae,
Serranidae) were sampled. The
sample
size, minimum
and maximum value of length and weight and
mean
values of length and weight of each
species
as well as
the
parameters
a
and
b of
the length - weight
relationships,
and
the
coefficient
of determination r
2
are presented
in
Table
1.
The length of the fishes
ranged from 9.2cm (
Siganus javus
and
Scatophagus
argus)
to 31.2cm (
Epinephelus coioides
) and weight
ranged from 16.1g (
Siganus canaliculatus
and
Acanthurus tristis
) and 373.1g (
Epinephelus coioides
)
.
The r
2
values ranged from 0.93 (
Epinephelus coioides
)
and 0.98 (
Lutjanus russellii
).
The exponent b of length-weight relationships ranged
between 2.71 for
Scatophagus argus
and 3.20 for
Upeneus vittatus
. The LWR were significant (p<0.05)
for these coral reef associated species. In terms of
growth type, the results revealed that seven species
