The effect of white, green, blue and yellow coloured drift gill nets on their catch with respect to Scomberomorus guttatus (Schneider), Scomberomorus commerson (Lacepede), Scomberomorus lineolatus (Cuvier), Parastomateus niger (Bloch), Euthynnus ajjinis (Cantor) and sharks Carcharius melanopterus is discussed. White nets were more effective for S. guttatus while the coloured ones caught more of P. niger. Blue had no significant effect for sharks. In the case of S. lineolatus, S. commerson and E. affinis no preference to colour was noted

Dawson, P.

Rao, J.S.

Sreekrishna, Y.

Aquatic Commons

Fish. Techno!. (1980) 17,, 75-77 
Effect of Col our on the Catch of Gill ets 
J. SITARAMA RAO, PERCY DAWSON* and Y. SREEKRISHNA** 
Kakinada Research Centre of Central Institute of Fisheries Technology, Kakinada-533 003 
The effect of white, green, blue and yellow coloured drift gill nets on their catch with 
respect to Scomberomorus guttatus (Schneider), Scomberomorus commerson (Lacepede), 
Scomberomorus lineolatus (Cuvier), Parastomateus niger (Bloch), Euthynnus ajjinis 
(Cantor) and sharks Carcharius melanopterus is discussed. White nets were more 
effective for S. guttatus while the coloured ones caught more of P. niger. Blue had no 
significant effect for sharks. In the case of S. lineolatus, S. commerson and E. affinis no 
preference to colour was noted. 
As the visibility of the fishing net in the 
water has an effect on its c?.tch, many 
workers studied the effect of coloured nets 
(Nomura, 1959, 1961; Von Brandt & 
Liepolt, 1955; Andreev, 1958; Levy, 1964). 
Nomura (1961) noted increased catch in 
dark coloured nets during d::l.y with no effect 
during night. Andreev (1962) found that 
n'::ts dyed with light colour did not fish well. 
Jester (1973) indicated that colour is species 
specific. Attempts have not been made in 
India to study the effect of coloured gill 
nets on catch. This paper reports the 
attempt of th~ authors to study the effect of 
coloured gill nets on the catch of seer, 
pomfret, tuna and sharks along the Andhra 
coast. 
Materials and Methods 
The material was polyamide white twine 
of Nm 34/3/3 with a uniform mesh size of 
50 mm bar, undyed and dyed with 
green, blue and yellow. The twines were 
kept for 20 min. at 60°C in a 1 % solution 
of neutral soap and ammonia (1 :1). Sl].bse-
quently it was kept in a bath with material 
to dye bath ratio 1 :10 at a dye concentration 
of 0.1 %. To this, acetic acid was added to 
get a pH of 3-4. The solution was heated 
to 60°C and the material after thorough 
washing and drying is introduced to the dye 
solution and heated to boil for 30 min. The 
material was taken out, excess dye solution 
was drained, washed and dried. Dyes used 
Present address: *Burla Kesearch Centre of Central 
Institute of Fisheries Technology, Burla-768017 
**Central Institute of Fisheries Education, Versova, 
Born bay-400058 
Vol. 17 
were manufactured by M/s. Sandoz (India) 
Ltd., Bombay. The net fleet had 16 units, 
the combination being four under each 
colour. Each net had 50 m mounted length 
and 6 m hung depth. The nets were operated 
in juxtaposition as surface drift at 20-65 m 
off Kakinada giving equal chances for all 
units. 
Results and Discussion 
Table 1 shows that in general, white nets 
caught more of S. guttatus, while blue and 
yellow caught more of S. commerson. It is seen 
that for S. guttatus, variation between days 
and colours is significant at 1 %level. Critical 
difference in catch w2.s worked out to be 
0.09365 with the mean logarithmic catch of 
the four different coloured nets as 0.4012 
(white), 0.2411 (green), 0.1679 (yellow) and 
0.2300 (blue). Accordingly white nets gave 
significantly higher catch in comparison with 
the other three, which were more or less 
silT'.ilar in their catching rate. As regards 
S. commerson and S. lineolatus the variance 
between nets and days was not significant 
even at 5% level indicating similarity of 
catch r2.te in aU nets (Table 1). As only 
limited number of these species were caught 
further experiments are necessary for con-
firmation. 
The catching rate is different for different 
coloured nets (Table 2). P. niger was 
caught more in green nets, whereas E. ajjinis 
was relatively more in green nets followed 
by white and sharks in yellow. The chi.-
square test (Table 2) reveals that in P. niger 
and sharks, the colour of · the net has 
Ta
bl
e 
1.
 
An
al
ys
is
 o
f v
a
ria
nc
e 
-
-
.
1 
0
\ 
W
hi
te
 
G
re
en
 
Y
el
lo
w
 
B
lu
e 
n
o
 
w
t 
n
o
 
w
t 
n
o
 
w
t 
n
o
 
w
t 
ss
 
D
F 
M
S 
F 
S.
 g
ut
ta
tu
s 
69
 
71
.9
5 
39
 
43
.0
0 
26
 
34
~0
5 
38
 
40
.9
0 
T
ot
al
 
8.
89
56
 
14
3 
B
et
w
ee
n 
1.
07
90
 
3 
0.
35
63
 
8.
67
':' 
n
e
ts
 
B
et
w
ee
n 
3.
50
47
 
35
 
0.
10
01
 
2.
47
* 
da
ys
 
~
 
(/
) 
E
rr
or
 
4.
32
18
 
10
5 
0.
04
11
 
-
""
"'
 ~ 
S.
 
c
o
m
m
e
rs
o
n
 
6 
13
.5
0 
3 
9.
05
 
10
 
30
.6
5 
11
 
38
.0
0 
To
ta
l 
1.
98
92
 
67
 
~ 
B
et
w
ee
n 
0.
12
62
 
3 
0.
04
21
 
1.
30
 
n
et
s 
~ 
B
et
w
ee
n 
0.
31
12
 
16
 
0.
01
94
 
0.
60
 
da
ys
 
~ 
E
rr
or
 
1.
55
13
 
48
 
0.
03
23
 
-
0 . 
S.
 li
ne
ol
at
us
 
10
 
18
.4
0 
3 
4.
50
 
5 
11
.2
0 
6 
10
.7
0 
T
ot
al
 
1.
35
70
 
27
 
"
0 
-
-
trJ
 
B
et
w
ee
n 
0.
17
22
 
3 
0.
05
74
 
1.
02
 
?:1
 
n
et
s 
Cl
 
B
et
w
ee
n 
0.
17
05
 
6 
0.
02
84
 
0.
50
 
~ ti
 
da
ys
 
~ 
E
rr
or
 
1.
01
43
 
18
 
0.
05
63
 
-
~:~ 
Si
gn
ifi
ca
nt
 a
t 
1 %
 lev
el
 
(/
) 0 z >
 
Ta
bl
e 
2. 
Ch
i~
sq
ua
re
 a
n
a
ly
sis
 fo
r P
. n
ig
er
, E
. 
a
ffin
is 
a
n
d.
sh
ar
k 
z ti
 
W
hi
te
 
G
re
en
 
Y
el
lo
w
 
B
lu
e 
C
al
cu
-
D
F 
R
em
ar
ks
 
;< 
I a
 te
d 
(/
) 
Sp
ec
ie
s 
n
o
 
w
t 
n
o
 
w
t 
n
o
 
w
t 
n
o
 
w
t 
X2
 
?:1
 
trJ
 
P.
 n
ig
er
 
69
 
52
.0
0 
11
9 
72
.1
3 
10
2 
65
.7
7 
11
3 
71
.9
9 
14
.7
8 
3 
0.
01
 <
 p
 <
 0
.0
01
 
trJ
 ?'1 ?:1 
E.
 a
ffin
is 
10
6.
20
 
86
.1
0 
40
 
6.
08
 
3 
0.
20
< 
P
<
 0.
10
 
""
"'
 
59
 
97
.3
0 
63
 
49
 
63
.6
0 
(/
) :I: 
'-
0 
Sh
ar
ks
 
9.
48
 
3 
0.
05
<P
<0
.0
2 
~ 
0
0
 
62
 
21
6.
65
 
58
 
15
0.
95
 
71
 
27
1.
95
 
39
 
17
0.
20
 
0 
EFFECT OF COLOUR ON THE CATCH OF GILL NETS 77 
Table 3. Chi-square analysis for P. niger and shark 
Colour X 
P. niger Green, blue and 1.34 
yellow 
Shgrks White, green and 1.39 
yellow 
significant effect on the catch, but not in E. 
affinis. Hsiao (1951) while studying the 
response of five tunnies to artificial light by 
confining them in a tank illuminated with 
two 60 W bulbs and coloured lights of 
moderate: intensity, observed that they were 
equally attr:J.cted by coloured and white 
lights. But Hsia.o & Jester (1952) found 
that white lures were slightly superior to 
coloured ones, white was not significant to 
P. niger and blue to sharks cmd hence chi-
square wa.s applied for the three coloured 
nets le2.ving the one with less ca.tch in the 
case of P. niger and sharks (Table 3). The 
chi-square test indica.ted that for P. niger 
the effect of green, yellow and blue was the 
same while for sharks white, green and 
yellow was equaJ. 
The authors wish to express their gratitude to 
Shri. G. K. Kuriyan, Director, Central Institute of 
Fisheries Technology, Cochin and Shri A. V. V. 
Satyanarayana, Scientist for their guidance, 
suggestion, and reading the manuscript and to the 
Statistical Section for the help in the statistical 
analysis. 
References 
Andreev, N. N. (1962) Hand Book of 
Fishing Gear and its Rigging. Cat. 
Vol. I 7 
DF Remarks 
2 0.70 p 0.50 
2 0.50 p p.30 
No. 654, Israel Programme for Scien-
tific Translation, Jerusalem (Translated 
from Russian) 
Hsiao, S. C. (1951) U.S. Fish and Wild 
Life Service Spec. Report. 91, p. 36, 
Bureau of Commercial Fisheries, 
Washington 
Hsiao, S. C. & Jester, A. L. (1952) U.S. 
Fish. end Wild Life Service Spec. Report. 
130, p.63, Bureau of Commercial 
Fisheries, Washington 
Jester, D. B. (1963) Trans. Amer. Fish. 
Sec. 1, 109 
Levy, H. (1964) m Modern Fishing Gear 
of the World. (Kristjonsson, H., Ed.) 
Vol. 2, p. 582, Fishing News (Books) 
Ltd., London 
Nomura, M. (1959) 111 Modern Fishing 
Gear of the World. (Kristjonsson, 
H. Ed.) Vol. 1, p. 550, Fishing News 
(Books) Ltd., London 
Nomura, M. (1961) Bull. Tokai Reg. Fish 
Res. Lab. 30, 1 
Von Brandt, A. & Liepolt, R. (1955) 
Oeslerreichs Fischerci, 8, (9/10), 93 


Effect of colour on the catch of gill nets

http://aquaticcommons.org/18091/1/FT17.2_075.pdf

Effect of colour on the catch of gill nets

Abstract

Similar works

Full text

Available Versions

Aquatic Commons