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Reservoir Fisheries………?-223-
Chapter VII
Reservoir Fisheries
Freshwater resources are one of the most precious
commodities for the living beings and especially to human beings.
Aquatic resources of water should be assessed on the basis of abiotic
and biotic parameters in order to provide the complete spectrum of
information for the conservation, assessment of fish diversity and
better fish-management and sustainable utilization. Rapid industrial
growth in the post-independent India resulting in deforestation,
unscrupulous exploitation of river water for irrigation, siltation of
river beds and reservoirs, unattended fish catches by the untrained
fisherman, destructive fishing, damming, habitat fragmentation, loss
of habitat, predation, diseases, etc. has drastically decreased the fish
diversity in the natural waters (Mudgal, 2007).
India being the fourth largest producer of fish in the world and
second in inland fish production, its share in the world production of
fish is about 4.6 %. Fisheries sector has been recognized as a
powerful income and employment generator as it stimulates growth
of a number of subsidiary industries and is a source of cheap and
nutritious food. At the same time, it is an instrument of livelihood for
a large section of economically backward population of the country.
More than 8.0 million fishers in the country directly depend on
fisheries and aquaculture for their livelihood (Chauhan, 2004;
Ayyappan et al. 2006).
Aquaculture in India is almost synonymous to carp culture,
since the latter alone contributes to more than 80 % of the total
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Reservoir Fisheries………?-224-
aquaculture production of the country. The carp culture mainly
involves three Indian major carps viz catla (Catla catla), rohu (Labeo
rohita) and mrigal (Cirrhinus mrigala) and three domesticated exotic
carps viz silver carp (Hypophthalmichthys molitrix), grass carp
(Ctenopharyngodon idella) and common carp (Cyprinus carpio)
Ayyappan et al. (2006). Reservoirs are generally stocked with
fingerlings of Indian major carps and indigenous medium sized carps
to augment their fish production. World’s major concerns are the
aquatic resources as the rapidly increasing human population is
resulting in tremendous pressure on food security. By 2010, an
additional 40-50 million tones of fish is expected to be required to
maintain the present global per capita availability of food fish.
However, the gap between production and per capita requirement is
still very large.
According to Chauhan (2004) India is reckoned to be self-
sufficient in carp fish seed to meet the demand of aqua farming. The
present carp seed production is about 17,000 million fry and it is
envisaged to achieve a target of 25,000 million fry by 2009-10. The
only alternative is to strengthen and sustain fish farming and culture
based capture fisheries by employing better management practices
and ensuring enhanced fish production as well as the environmental
sustainability. World Fish Center (2003) has also envisaged major
growth in fish farming in Asia particularly in India, where it is
expected to increase by 67 % by 2020.
Reservoirs are important water resources in Asia; the
reservoirs are diverse and therefore the strategies to be adopted for
optimizing yields are also different (Bhukaswan 1980; Cowx, 1996;
De Silva, 2001). The fish production from reservoir depends on
nutrients, biomass, and the quantity of stocked fingerlings.
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There is a common belief that fish yields of reservoirs tend to be high
in the initial few years after impoundment, and then begin to
stabilize at a lower level (Van & Luu, 2001). As indicated by
Bernacsek (1997) fish catch per unit effort is quite low in large
reservoirs, mainly due to the low productivity of pelagic water.
Recently, reservoir fisheries resources have tended to be
overexploited (Coates 2002; Cowx, 2002). First of all this is caused
by ineffective or inappropriate management measures. Open access
may be an important cause of over fishing, and lack of knowledge on
fisheries resources may lead to or results in over fishing (Coates,
2002).
Sharma et al. (1986) and Joshi (1987) reported the induced
breeding of Labeo gonius in Rajasthan having warm climatic
condition. Labeo rohita is the important commercial fish species,
most favoured by consumers of India, fetching a high price of Rs. 40
to 50 per kg for the marketable size. It is column feeder and mainly
feeds on decaying plants and detritus. It likes artificial feed and has
a good capacity to convert it into flesh. Usually low temperatures are
harmful for growth and reproduction of fishes (Popma and Lovshin,
1996).
The fishery of Indian reservoirs is comprised of both
indigenous and stocked fish populations. Among the former, the
Gangetic major carps occupy a prominent place in north Indian
reservoirs both as naturally-occurring and stocked species. In
addition to this, they also harbour many species of common carps,
major and minor catfishes and miscellaneous species. The important
species accounting for major parts of the catch are Catla catla,
Cirrhinus mrigala, Labeo rohita, L. calbasu, L. bata, Puntius sarana, P.
chagunio, C. reba, Mystus. aor, M. seenghala, Wallago attu, etc.
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Reservoir fishery is an important component of the inland
fisheries in South and South-East Asia. In India, the total water
spread area under all categories of reservoirs is estimated to be
about 3.0 million ha, which constitutes about 50 % of total reservoir
area in South-East Asia (Singh, 2001). Indian reservoirs, being in
tropics, have a high primary productivity and have the capacity to
produce more fish yield. Minor reservoirs are amenable to more
effective fisheries management than the large reservoirs (Jhingran
and Sugunan, 1990; Devi, 1997; Piska, 1999 and 2000; Chavan,
2006 and Vass, 2006). According to Kang (1992) the average fish
production of India is 20 kg/ha whereas that of Thailand is 47
kg/ha; Sri Lanka 283 kg/ha and China 150 kg/ha. Thus India is at
the bottom of the list though the scientific man-power in fisheries
sector of India is very high. The Chinese treat reservoir fishery as
“culture” fisheries. The hydrobiology is considered as the key to
fishery management.
Length-weight relationship for any fish species gives its
performance and well being in relation to habitat and helps in
monitoring the status of fish stock for obtaining optimum yield.
These relationships may vary from time to time in the same water
body due to alterations in water quality and fish stocks. Most of the
fishes compete for food with carps tending to reduce the overall fish
productivity of the reservoir (Ayyappan et al., 2006). The general
concept of length-weight relationship is that the weight of fish varies
as the cube of its length. But as the specific gravity and shape or
body outline of the fish is subjected to changes, the cube law is not
always applicable (Rounsefell and Everhart, 1953). Various workers
have studied the length-weight relationship of different fishes like
Labeo calbasu (Pathak, 1975), Notopterus notopterus (Kalita and
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Reservoir Fisheries………?-227-
Rath, 1998), Catla catla (Jhajhria, 2003), Cyprinus carpio (Saran and
Mohan, 2004) Clarias gariepinus (Nath et al., 2006), and Puntius
sophore (Shendge, 2008).
Observations
(A) Fish fauna of the reservoir
The fish fauna of Baigul reservoir has been studied during the
present investigation. Baigul reservoir has a rich assemblage of both
naturally occurring and stocked fish species. The reservoir is leased
to a contractor for 3-5 years for fishing and the fishing season
extends from October to June. The contractor employs various
parties of fishermen for fish catch. There is only one landing centre
where all catches are brought together. The assembled catches after
local consumption in fresh condition are transported to the other
markets. In addition to the fresh trade, smaller varieties of fish
(Puntius spp., Gudusia chapra and Prawns spp.) are also dried and
supplied to other places (U.P., Delhi etc.) (Table 7.1).
The fish fauna is comprised of major carps, cat fishes, minor
carps and a large population of trash fishes. A total of 36 species of
fish belonging to 13 families were identified in the reservoir. Among
13 families Clupideae, Notopteridae, Cyprinidae, Siluridae,
Channidae and Bagridae were the most common. The fish species
such as Labeo calbasu, Catla catlaL. gonius, L. rohita, Puntius sp.,
Cirrhinus mrigala, C. reba, Mystus tengara, M. seenghala, Nandus
nandus Gudusia chapra, N. notopterus, Wallago attu, Xenentodon
cancila and M. armatus etc. were quantitatively the main components
of the fishery of the reservoir (Plate 13 and 14).
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Table 7.1 : Fish fauna of the baigul reservoirS. No. Families Species Local name Abundance
1 Clupideae Gudusia chapra Suhia ANotopterus notopterus Patra A2 NotopteridaeN. chitala Moya SCyprinus carpio Common carp LTor tor Mahaseer SB. bendelisis Bhola SPuntius sophore Sidhari LP. sarana Sidhari MCirrhinus mrigala Mrigal/Nain MC. reba Raia MLabeo gonius Kursa AL.bata Bata LL. rohita Rohu LL. calbasu Karaunch MOxygaster bacaila Chilwa L
3 Cyprinidae
Catla catla Katla LMystus seenghala Dariai tengar LM. cavasius Sutahawa
tengaraL
M. vittatus Tengara SM.oar Dariai tengar S
4 Bagridae
M.tengara Tengara M5 Heteropneustidae Heteropneustus fossilis Singhi L
Ompak pabda Pabda M6 SiluridaeWallago attu Padhani/Lanchi S
7 Claridae Clarias batrachus Magur L8 Belonidae Xenentodon cancila Kauwa M
Channa gachua Changa MC. marulius Saur AC.punctatus Girai A
9 Channidae
C. striatus Saur A10 Anabantidae Colisa fasciatus Khosti S11 Centropomidae Chanda ranga Chanari M12 Nandidae Nandus nandus Dhebari M
Mastacembelus armatus Baam MM. pancalus Malga/Patya L
13 Mastacembelidae
M. aculeatus Malga/Patya LA = Most abundant, M = Moderately abundant, L = Less abundant, S = Seasonally
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Labeo rohita Gadusia chapra
Notopterus notopterus Cirrhinus reba
Labeo calbasu Cirrhinus mrigala
Plate 13 : Different species of fishes recorded from Baigulreservoir
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Labeo gonius Catla catla
Mystus tengara Xenentodon cancila
Nandus nandus Puntius sp.
Plate 14 : Different species of fishes recorded from Baigulreservoir
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Fish and Fisheries
The findings have revealed that the Baigul reservoir harbours a
variety of fish fauna. The results of the present study have been
presented in two parts. The first part deals with the collection and
identification of collected specimen and enlisting of the fish species
recorded during the study period; while the second part deals with a
comprehensive discussion based on the present fish production data
obtained from State Fisheries Department, Uttarakhand.
(B) Catch composition
In the Baigul reservoir, the commercial fishing is started in
October and continued up to June. Almost immediately after the fish
are brought to the shore, these are grouped into three classes viz.,
class-A, class-B and class-C according to their respective market rates.
In the present investigation the monthly data on fish catch from
January to December are presented in a systematic manner. The
species wise data are divided into 4/5 groups: The first group, major
carps which comprises of Labeo rohita, Catla catla, Cirrhinus mrigala
and Labeo calbasu, while the second group includes cat fishes: Mystus
sp. and Channa striatus. The third group includes minor carps such as
Labeo gonius and Notopterus notopterus. The fourth group includes
other fishes and the fifth is weed fishes including, Gudusia chapra, etc.
(Plate 15 and 16). Total catch composition of Baigul reservoir was
199393 kg during the study period (Table 7.2 Fig. 7.1 and 7.2).
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Plate 15 : Haul of Labeo gonius , the dominant fish of Baigul
Plate 16 : Fish haul with majority of weed fishes
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Reservoir Fisheries………?-233-
Table 7.2 : Total catch composition (in Kg.) of Baigul reservoir (2005)
Months A class B1 class B2 class B3 class C class Total
Jan 1001.0 965.0 3818.0 2573.0 26611.0 34968.0
Feb 462.0 608.0 14128.0 3448.0 9384.0 28030.0
Mar 661.0 725.0 14719.0 3043.0 2266.0 21414.0
Apr 836.0 708.0 12686.0 1175.0 434.0 15839.0
May 3184.0 1386.0 13180.0 513.0 5.0 18268.0
Jun 5652.0 1498.0 16288.0 1700.0 0.0 25138.0
Jul 0.0 0.0 0.0 0.0 0.0 0.0
Aug 0.0 0.0 0.0 0.0 0.0 0.0
Sep 0.0 0.0 0.0 0.0 0.0 0.0
Oct 256.0 739.0 8315.0 564.0 5615.0 15489.0
Nov 187.0 849.0 7443.0 572.0 8170.0 17221.0
Dec 576.0 1464.0 6996.0 1191.0 12799.0 23026.0
Total 12815.0 8942.0 97573.0 14779.0 65284.0 199393.0
Percentage 6.43 4.48 48.94 7.41 32.74 100.0
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128158942
97573
14779
65284
0
10000
20000
30000
40000
50000
60000
70000
80000
90000
100000
Fish
pro
duct
ion
(kg)
A class B1 class B2 class B3 class C class
2005
Classwise total
Fig. 7.1 : Classwise total fish production in Baigul reservoir
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Reservoir Fisheries………?-235-
6.434.48
48.947.41
32.74
A class B1 class B2 class B3 class C class
Fig. 7.2 : Classwise per cent contribution of total fish production in Baigul reservoirEste
lar
Reservoir Fisheries………?-236-
Class wise monthly variations in fish production
Class - A:
The monthly variations in the fish production of class A are
presented in the Fig. 7.3. It was observed that the highest production
(5,652 kg) of class-A was found during June followed by 3,184 kg in
May. Lower production was recorded in the month of November
(187.0 kg). Production of this fish showed increasing trend from
March onwards till June. Further, the total production of this fish
category recorded during January to December was (12,815.0 kg).
The class-A contributed only (6.43 %) to the total fish production of
Baigul reservoir (Fig. 7.2 and 7.3).
Class – B1
The share in production by this category is depicted in Fig. 7.3.
The highest production (1498.0 kg) was found during June followed
by May (1386.0 kg); while the lowest production was found in the
month of February (608.0 kg). Irregular trends in production
category II were observed during the present investigation. The total
production of class-B1 was 8,942.0 kg (Fig. 7.3). This category
contributed 4.48 % to the total fish production. Another notable
feature observed in the present study showed that share of this class
has increased relatively than in earlier years.
Class – B2
The fluctuations in production by class-B2 are depicted in
Fig. 7.4. It is apparent that the highest production (16288.0 kg) of
class–B2 was recorded during June followed by 14719.0 kg
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1001
462661
836
3184
5652
0 0 0256 187
576
0
1000
2000
3000
4000
5000
6000
Fish
pro
duct
ion
(kg)
Jan Feb Mar Apr May Jun Jul Aug Sep Oct Nov Dec
A class
965
608
725 708
1386
1498
0 0 0
739
849
1464
0
200
400
600
800
1000
1200
1400
1600
Fish
pro
duct
ion
(kg)
Jan Feb Mar Apr May Jun Jul Aug Sep Oct Nov Dec
Months (2005)
B1 class
Fig. 7.3 : Monthly fish production of A & B1 Classes in Baigul reservoir
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Reservoir Fisheries………?-238-
production in March. The data also depicted that production in the
months of February (14128.0 kg) and March (14719.0 kg) was
almost similar; while the production was least (3818.0 kg) in the
month of January (Fig. 7.4). The total production of class-B2 was
97573.0 kg. It is obvious from the catch data that with high share in
the total fish catch, this class was most dominant.
Class – B3
The monthly variations in the production of class-B3 are
depicted in Fig. 7.4. It is evident that the highest production 3,448
kg of class-B3 was recorded during February followed by 3,043 kg in
March. The data also showed that production in the months of
October (564.0 kg) and November (572.0 kg) was close to each other;
while the least production was observed in the month of May (513.0
kg). A decreasing trend in the production was observed from
February to May. A total of 14,779 kg fish production was recorded
from January to December. The class-B3 contributed (7.41 %) to the
total fish landings.
Class - C
Small fish of low commercial value are included in this class-C.
The catch data of this category are depicted in Fig. 7.5. The highest
production (26,611 kg) of this category was found during January
followed by December (12,799 kg). The lowest production was found
in May (5.0 kg). A decreasing trend in fish production was observed
from February to June. The total production of this category was
65,284 kg. Further class-C contributed (32.74 %) to the total fish
production.
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Reservoir Fisheries………?-239-
3818
1412814719
1268613180
16288
0 0 0
83157443 6996
0
2000
4000
6000
8000
10000
12000
14000
16000
18000
Fish
pro
duct
ion
(kg)
Jan Feb Mar Apr May Jun Jul Aug Sep Oct Nov Dec
B2 class
2573
34483043
1175
513
1700
0 0 0
564 572
1191
0
500
1000
1500
2000
2500
3000
3500
Fish
pro
duct
ion
(kg)
Jan Feb Mar Apr May Jun Jul Aug Sep Oct Nov Dec
Months (2005)
B3 class
Fig. 7.4 : Monthly fish production of B2 & B3 Classes in Baigul reservoir
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Reservoir Fisheries………?-240-
26611
9384
2266
4345 0 0 0 0
5615
8170
12799
0
5000
10000
15000
20000
25000
30000
Fish
pro
duct
ion
(kg)
Jan Feb Mar Apr May Jun Jul Aug Sep Oct Nov Dec
Months (2005)
C class
Fig. 7.5 : Monthly fish production of class C in Baigul reservoir
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Reservoir Fisheries………?-241-
(C) Important food fishes (species wise)
Major carps are highly esteemed as food fishes in this region
because of good taste. Among the cat fishes, Mystus sp. has a good
demand in this area, because of high quality flesh. The principal food
fishes of Baigul reservoir in order of importance are given below:
SI. No. Groups Species
(A) Major carps Labeo rohita, L. calbasu, Catla catla andCirrhinus mrigala
(B1) Cat fishes Mystus tengara and Channa striatus
(B2) Minor carps Labeo gonius, and Notopterus notopterus
(B3) Weed fishes Gudusia chapra
(C) Other fishes Heteropneustes fossilis, Nandus nandus andMastacembelus armatus etc.
I. Major carps: These contributed 6.43 % to the total production.
Labeo rohita
The total monthly fish landings are shown in the Fig. 7.6. The
production of L. rohita varied from 13.0 to 2412.0 kg during the
present investigation. The highest fish production of 2412.0 kg was
recorded during June followed by 1200.5 kg production in May. The
data also depicted that catch in the month of April (159.5 kg) and
December (105.5 kg) were almost same; the lowest fish catch of 13.0
kg was observed during November. The total production 4,336.0 kg
was recorded during January to December. L. rohita contributed 2.17
% to the total landings from this reservoir (Fig. 7.7).
Catla catla
The monthly variations of Catla catla are presented in Fig.
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Reservoir Fisheries………?-242-
34968
28030
21414
15839
18268
25138
0 0 0
1548917221
23026
0
5000
10000
15000
20000
25000
30000
35000
Fish
pro
duct
ion
(kg)
Jan Feb Mar Apr May Jun Jul Aug Sep Oct Nov Dec
Months (2005)
Monthwise total
Fig. 7.6 : Monthwise total fish production in Baigul reservoirEstelar
Reservoir Fisheries………?-243-
2.17 0.58 2.09 0.68
40.83
7.921.222.86
7.41
29.53
Rohu Catla Mrigal Karuanch Kursa
Patra Tengan Saur Others Gudusia
Fig.7.7 : Per cent contribution of important fishes to total fish production in Baigul reservoirEste
lar
Reservoir Fisheries………?-244-
7.8. The highest production (676.0 kg) of C. catla was recorded
during June followed by 168.0 kg production in May. On the
contrary, the recorded production was least in the month of
February (7.0 kg). The total production recorded from January to
December was 1156.0 kg. C. catla contributed about 0.58 % to the
total landings in Baigul reservoir (Fig. 7.7).
Cirrhinus mrigala
The monthly variations in the production of C. mrigala are
depicted in Fig. 7.9. The highest production (1427.0 kg) was found
during June followed by 936.0 kg production in May. The lowest
production was recorded in November (142.6 kg). A gradually
increasing trend in production was observed from March to June;
decreasing trend in production was observed from October to
November. A total 4177.1 kg fish production was recorded from
January to December. The fish contributed about 2.09 % to the total
production landing from Baigul reservoir (Fig. 7.7).
Labeo calbasu
The production of L. calbasu varied between 13.5 and 330.0 kg
in the Baigul reservoir. The monthly fish landings are shown in Fig.
7.9. The highest fish production of 330.0 kg was recorded during
May. The catches during February - March were 126.0 - 127.0 kg
and that during May- June were 317-330.0 kg. The lowest fish catch
of 13.5 kg was observed during October. The total production from
January to December 05 was recorded as 1,346.0 kg. L. calbasu
contributed about 0.68 % to the total landings during the present
investigation (Fig. 7.7).
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Reservoir Fisheries………?-245-
251
71.5 97159.5
1200.5
2412
0 0 0 26 13105.5
0
500
1000
1500
2000
2500
Fish
pro
duct
ion
(kg)
Jan Feb Mar Apr May Jun Jul Aug Sep Oct Nov Dec
Labeo rohita
92
7 13.530
168
676
0 0 0 17 7.5
145
0
100
200
300
400
500
600
700
Fish
pro
duct
ion
(kg)
Jan Feb Mar Apr May Jun Jul Aug Sep Oct Nov Dec
Months (2005)
Catla catla
Fig. 7.8 : Monthly fish production of Labeo rohita and Catla catla in Baigul reservoir
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Reservoir Fisheries………?-246-
392.5
206.5
321378
936
1427
0 0 0
177 142.6196.5
0
200
400
600
800
1000
1200
1400
1600
Fish
pro
duct
ion
(kg)
Jan Feb Mar Apr May Jun Jul Aug Sep Oct Nov Dec
Cirrhinus mrigala
192.5
127 126
203.5
330317
0 0 0 13.5 1422.5
0
50
100
150
200
250
300
350
Fish
pro
duct
ion
(kg)
Jan Feb Mar Apr May Jun Jul Aug Sep Oct Nov Dec
Months (2005)
Labeo calbasu
Fig. 7.9 : Monthly fish production of Cirrhinus mrigala and Labeo calbasu in Baigul reservoir
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Reservoir Fisheries………?-247-
Cat fishes
The contribution of cat fishes was 4.48 % to the total fish
landings of Baigul reservoir.
Mystus tengara
It is evident from the monthly variations that the highest
production (485.0 kg) was found during June (Fig. 7.10). The lowest
production was recorded in the month of March (101.0 kg). A total
production of 2,434.0 kg was recorded during the study period. M.
tengara contributed about 1.22 % to the total fish landings from this
reservoir (Fig. 7.7).
Channa striatus
The monthly production of C. striatus varied from 367.0 to
1031.0 kg. The total production of this fish was 5697.0 kg during the
study period (Fig. 7.10). The highest production (1031.0 kg) was
noted during December followed by 960.0 kg in the month of June.
The lowest production was recorded in the month of February (367.0
kg). Irregular trends in fish production were observed throughout the
study period. C. striatus contributed about 2.86 % to the total
landings from this reservoir (Fig. 7.7).
Minor carps
Minor carps contributed about 48.94 % to the total fish
production.
Labeo gonius
The production of L. gonius varied from 2676.0 to 15155.0 kg.
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Reservoir Fisheries………?-248-
393
167
101
226
432
485
0 0 0
169 169
292
0
50
100
150
200
250
300
350
400
450
500
Fish
pro
duct
ion
(kg)
Jan Feb Mar Apr May Jun Jul Aug Sep Oct Nov Dec
Mystus tengara
446
367
492
419.5
894.5960
0 0 0
486
601
1031
0
200
400
600
800
1000
1200
Fish
pro
duct
ion
(kg)
Jan Feb Mar Apr May Jun Jul Aug Sep Oct Nov Dec
Months (2005)
Channa striatus
Fig. 7.10 : Monthly fish production of Mystus tengara and Channa striatus in Baigul reservoir
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Reservoir Fisheries………?-249-
The monthly fish landings are shown in Fig. 7.11. The highest fish
production of 15155.0 kg was observed in June followed by 13477.0
kg production in March; while the lowest fish catch of 2676.0 kg was
recorded during January. The total production recorded form
January to December was 81406.0 kg. L. gonius dominated the
fishery followed by Notopterus notopterus in the minor carps group.
L. gonius contributed about 40.83 % to the total landings from this
reservoir (Fig. 7.7).
Notopterus notopterus
The monthly variations in the production of N. notopterus are
depicted in Fig. 7.11; it is evident that highest production of 2346.0
kg was observed during April followed by 2140.0 kg production in
December. The minimum production was recorded in the month of
June (1124.0 kg). The total annual production was recorded as
15784.0 kg. N. notopterus ranked second in the catches followed by
L. gonius in the minor carps group. N. notopterus contributed about
7.92 % to the total production from Baigul reservoir (Fig. 7.7).
Weed fishes
The contribution of weed fishes was 32.74 % to the total fish
landings of Baigul reservoir.
Gudusia chapra
The production of G. chapra varied from 5.0 to 24578.0 kg. The
highest production (24578.0 kg) was obtained during January (Fig.
7.12). The production of G. chapra was almost similar in the month
of February (8432.0 kg) and November (8170.0 kg). The fish was not
recorded in catches during April and June. The total production of
Estelar
Reservoir Fisheries………?-250-
2676
12032
13477
1034011258
15155
0 0 0
62405372
4856
0
2000
4000
6000
8000
10000
12000
14000
16000
Fish
pro
duct
ion
(kg)
Jan Feb Mar Apr May Jun Jul Aug Sep Oct Nov Dec
Labeo gonius
1142
1762
1242
2346
1922
1124
0 0 0
20352071
2140
0
500
1000
1500
2000
2500
Fish
pro
duct
ion
(kg)
Jan Feb Mar Apr May Jun Jul Aug Sep Oct Nov Dec
Months (2005)
Notopterus notopterus
Fig. 7.11: Monthly fish production of Labeo gonius and Notopterus notopterus in Baigul reservoir
Estelar
Reservoir Fisheries………?-251-
2573
3448
3043
1175
513
1700
0 0 0
564 572
1191
0
500
1000
1500
2000
2500
3000
3500
Fish
pro
duct
ion
(kg)
Jan Feb Mar Apr May Jun Jul Aug Sep Oct Nov Dec
Others
24578
8432
5880 5 0
0 0
4730
8170
12378
0
5000
10000
15000
20000
25000
Fish
pro
duct
ion
(kg)
Jan Feb Mar Apr May Jun Jul Aug Sep Oct Nov Dec
Months (2005)
Gudusia chapra
Fig 7.12 : Monthly fish production of Other fishes and Gudusia chapra in Baigul reservoir
Estelar
Reservoir Fisheries………?-252-
this fish recorded during present investigation, was 58881.0 kg. It
contributed 29.53 % to the total annual fish landings (Fig. 7.7).
Other fishes
These fishes shared 7.41 % to the total fish production in
Baigul reservoir. Monthly contribution by the other fishes is depicted
in Fig. 7.12. It is evident that the highest production (3448.0 kg) was
observed during February followed by March (3043.0 kg); the lowest
production was recorded in the month of May (513.0 kg). The data
further show variability in the production during different months.
The total production of this group of fishes recorded from January to
December was 14779.0 kg.
(D) Gear wise fish production
Fishing methods
The contractors mostly use traditional fishing methods in
Baigul reservoir for harvesting the fish catch. The commonly used
gears are gill net (Fansla jal); hooks and line (Dori), drag net (Chatti
jal), triangular net (Fautta or Jhinga jal), cast net (Ghagaria jal) and
rod and line (Bansi) (Plate 17 and 18).
Gill net
Like other reservoirs, gill net is the most common fishing gearemployed in Baigul reservoir throughout the year. The net is made ofnylon cord which is about 40 to 60 m long. Mostly 3 types of mesh
sizes, viz, 15×15 mm, 45×45 mm and 75×75 mm are used forcatching minor carps, major carps and cat fishes etc. The upper edge
of the net is attached with a series of floats, whereas sinkers aresuspended at the bottom edge of the net. The net is vertically
Estelar
Reservoir Fisheries………?-253-
Drag net with 1 × 1 mm mesh bar
Gill net with 15 × 15 mm mesh bar
Plate 17 : Drag net and gill net used for fishing in Baigul reservoir
Estelar
Reservoir Fisheries………?-254-
Gill net with 45 × 45 mm mesh bar
Gill net with 75 × 75 mm mesh bar
Plate 18 : Gill net of different mesh bars used for fishingin Baigul reservoir
Estelar
Reservoir Fisheries………?-255-
suspended in water with the help of boats. The fishing operation
starts in the evening and the catch is hauled in the subsequent
morning. The operating unit usually comprises of one small boat and
two fishermen. The fishes commonly caught with this device include,
Labeo spp., Catla catla, Mystus seenghala, M. tengra, M. vittatus and
Wallago attu (Table 7.3).
Table 7.3: Class wise and gear wise fish production of Baigulreservoir
A class B1 class B2 class B3 class C class Total Percentage
Gill net 7073 3230 55740 8626 15425 90094 45.2
Triangularnet
1660 990 7450 1169 958 12227 6.1
Drag net 2280 1942 20585 2336 35471 62614 31.4
Cast net 1507 2110 11380 2043 11430 28470 14.3
Hook line 0 0 0 0 2000 2000 1.0
Line androd net
295 670 2418 605 0.0 3988 2.0
Total 12815 8942 97573 14779 65284 199393 100.0
Triangular net
Triangular nets are conical in shape and made of bamboo
pieces of about 1.2×1.2 ×2.0 m size. The length of the net may also
vary between 1.0 and 2.5 m. The posterior end of the net where the
catch is collected is known as ‘Bhog’. In the operation of this net the
fishermen dip the front edge of the net in shallow water and capture
small prawns and weed fishes like Puntius spp. and Chanda sp. The
mesh sizes of 5×5 mm to 5×10 mm are recommendable for capturing
commercially important fish species. If the net is to be used in
deeper waters, a small boat is of great help.
Estelar
Reservoir Fisheries………?-256-
Drag net
Drag net is very large in size which horizontally covers an
enormous area in length (350 to 400 m) and width (3 to 4 m). One
large and two small boats with 24-30 fishermen form one operational
unit. The mesh size of the net is about 1x1 mm. The head rope of
this net is supported by a strong cord and is provided with a large
number of wooden or plastic floats, whereas the food rope is tied
with a number of sinkers to keep the net suspended in water in
vertical position. The operational principle involves handing over one
end of the net to one party of fishermen standing on the reservoir
bank. The net is then spread out in water in the semicircular fashion
with the help of boats to encircle the fish shoal from all directions.
The operational boats then turn to hand over the other end of the net
to the second party of fishermen standing at another distant place on
the shore. The net is operated in the month of May and June to
catch the fishes like Heteropneustes fossilis, Channa spp.,
Mastacembelus spp., Chanda spp., Puntius spp. etc.
Cast net
The cast nets are also occasionally used for fish harvest from
the reservoir especially in the shallower regions. The use of this gear
is not very common owing to the vastness of the reservoir.
This net is circular in shape, which opens like an umbrella.
The bottom rope of the net, fitted along its opening, is usually
fastened with a number of weights which facilitate an easy
suspension of the net in the water. The recommended mesh size of
the net is 5×5 cm to 8×8 cm. The fisherman throws the net towards
the expected shoal site by keeping in hand the string at its apex in
Estelar
Reservoir Fisheries………?-257-
such a manner that it falls over the water body in a circular fashion.
The net suspends easily in water due to the presence of attached
weights. Subsequently, the fishermen haul the net by slowly pulling
the string and closing its circumference. The varieties of fishes
usually captured by the cast net include Labeo spp., Catla sp.,
Cirrhinus spp., Mystus spp., Wallago attu and other large size species
of food fishes present in the water.
Hooks and line
Hooks and line is another important fishing gear commonly
operated in Baigul reservoir during post monsoon and summer
months when the transparency of water is low. This device is usually
used to harvest cat fishes and murrels. Lines are made of long cords
of cotton or waste silk tied with 100 to 200 country made iron hooks.
The common baits used on the hooks comprise trash fishes, small
prawns, earthworms etc.
Line and rod
Lines and rods are also sometimes used for capturing fish by
the fishermen in summers. For this purpose, earthworms are used
as the common bait for capturing fishes such as Mystus spp. Wallago
attu and Channa spp.
Catch Statistics in relation to the nets- gears used
Gearwise distribution of catches in Baigul reservoir has been
computed during the study period (Table 7.3). Gill net is the most
common fishing gear employed during the study period in the
reservoir. The total catch by gill net was 90094 kg or 45.2 %. Out of
total catch the catch of class-A fishes (Labeo rohita, L. calbasu, Catla
Estelar
Reservoir Fisheries………?-258-
catla, Cirrhinus mrigala etc.), was 7073 kg. The total catch of B1
class (Mystus sp., Channa sp. etc.) was 3230 kg; B2 class
represented by minor carps (L. gonius, Notopterus notopterus etc.)
was 55740 kg; catch of other fishes was 8626 kg and whereas the
total catch of weed fishes (Gudusia chapra, Chanda ranga etc.) was
calculated as 15425 kg. It was observed that minor carps were the
major component (55740 kg) whereas minimum catch was of cat
fishes (3230 kg).
The total catches by triangular net was 12227 kg or 6.1 % of
the total catch comprising of A class fishes 1660 kg, was B1 class
(990 kg), minor carps (7450 kg), B3 class (1169 kg), and C class (958
kg). It was observed that the maximum catch (7450 kg) by triangular
nets was of minor carps and minimum catch (958 kg) was of weed
fishes (Table 7.3).
The total catch of drag net was 62614 kg or 31.4 %. Out of
total catch, 2280 kg was A class; 1942 kg was B1 class; 20585 kg
was B2 class; 2336 kg was B3 class and 35471 kg was C class in the
Baigul reservoir (Table 7.3). It was noted that the maximum catch of
35471 kg by drag net was of weed fishes and minimum catch of
1942 kg was of B2 class cat fishes.
The total catch of cast net was 28470 kg or 14.3 %, out of this
1507 kg was A class; 2110 kg was B1 class; 11380 kg was B2 class;
2043 kg was B3 class and 11430 kg was C class. The maximum
catch of 11430 kg by cast net comprised of weed fishes and
minimum catch of 1507 kg was of major carps (Table 7.3).
The total catch by hooks and line was 2000 kg or 1.0 %. Major
carps, cat fishes, minor carps and other fishes were not caught by
hook nets and only weed fishes were caught by hook nets (Table 7.3).
Estelar
Reservoir Fisheries………?-259-
The total catch of line and rod was 3988 kg or 2.0 % from which 295
kg was of major carps; 670 kg was of cat fishes; 2418 kg was of
minor carps and 605 kg was of other fishes. Line and rod was not
used to catch weed fishes (Table 7.3).
(E) Fish productivity of the reservoir
The fish catch statistics available from 2001-2005 were used to
estimate the fish yield for different years. On the basis of water
spread area of 2693 ha, the yield rates from the reservoir were
estimated to be 43.84 kg/ha (2001), 52.74 kg/ha (2002), 37.82
kg/ha (2003), 28.27 kg/ha (2004) and 74.04 kg/ha (2005) (Fig.
7.13). The reservoir, therefore, can be placed amongst the moderately
productive reservoirs. The catch/ha estimated for different years is
as follows:
Year Total catch (kg) Kg/ha
2001 118068 43.84
2002 142028 52.74
2003 101845 37.82
2004 76131 28.27
2005 199393 74.04
(F) Length-weight relationship of some important fishes
The regression equations describing length-weight relationship
in case of important fish species of Baigul reservoir are presented in
Table 7.4 and 7.5 as well as Figs. 7.14 to 7.17. Accordingly, the
coefficient of correlation ®, coefficient of determination (r2) and the
levels of significance (P) for the relationship between length and
Estelar
Reservoir Fisheries………?-260-
0
2000
0
4000
0
6000
0
8000
0
1000
00
1200
00
1400
00
1600
00
1800
00
2000
00
Kg
2001
2002
2003
2004
2005
Year
Fig.
7.1
3: T
otal
fish
pro
duct
ivity
(kg)
of l
ast f
ive
year
s in
Bai
gul r
eser
voir
A c
lass
B1
clas
sB
2 cl
ass
B3
clas
sC
cla
ss
Estelar
Reservoir Fisheries………?-261-
weight for Labeo rohita, Catla catla, Cirrhinus mrigala, Channa
striatus, Labeo gonius, Notopterus notopterus, Gudusia chapra and
Puntius sarana have been worked out.
Table 7.4: Equations describing length-weight relationship indifferent fishes
Fish Length weight equation
Labeo rohita Log W = -2.9945+1.7415 log L
Catla catla Log W = -3.3732+2.0561 log L
Cirrhinus mrigala Log W = -3.2783+1.8639 log L
Channa striatus Log W = -3.2949+2.0577 log L
Labeo gonius Log W = -3.0586+1.7138 log L
Notopterus notopterus Log W = -1.9404+0.9779 log L
Gudusia chapra Log W = 0.8005+0.1936 log L
Puntius sarana Log W = -1.7255+0.8609 log L
Table 7.5: Coefficient of correlation; coefficient ofdetermination and level of significance related withlength-weight relationship in different fishes
Fish No. ofspecies
Coefficient ofcorrelation
(r)
Coefficient ofdetermination
(r2)
Level ofsignificance
(P)Labeo rohita 45 0.908 0.824 <0.01
Catla catla 55 0.933 0.870 <0.01
Cirrhinus mrigala 58 0.957 0.915 <0.01
Channa striatus 45 0.876 0.767 <0.01
Labeo gonius 48 0.954 0.910 <0.01
Notopterus notopterus 60 0.871 0.758 <0.01
Gudusia chapra 52 0.888 0.789 <0.01
Puntius sarana 50 0.912 0.831 <0.01
Estelar
Reservoir Fisheries………?-262-
Labeo rohita
The length-weight relationship of L. rohita (Fig. 7.14) can be
expressed by the following equation:
Log w = -2.9945 + 1.7415 log L
r = 0.908
It is obvious from the above equation that the relationship
between length and weight is not perfectly linear (r = 0.908). Besides,
the value of coefficient of regression is also very low (1.7415), which
is indicative of the fact that this fish becomes more slender with the
increase in body length. A fairly high value of coefficient of
determination (r2 = 0.824) was obtained (Table 7.4 and 7.5).
Catla catla
In case of C. catla, the logarithmic regression equation
obtained was as follows:
Low w = -3.3732 + 2.0561
r = 0.933
It is evident that the length-weight relationship of C. catla is
comparatively more fairly high (r = 0.933). A relatively high value of
coefficient of regression (2.0561) revealed that this fish also acquired
a slender form (Table 7.4 and 7.5, Fig. 7.14).
Cirrhinus mrigala
In case of C. mrigala, the logarithmic regression equation
obtained was as follows:
Low w = -3.2783 + 1.8639 log L
r = 0.957
Estelar
Reservoir Fisheries………?-263-
Labeo rohita
y = 55.143x - 987.4R2 = 0.824
0
500
1000
1500
2000
2500
3000
3500
4000
0 10 20 30 40 50 60 70
Length (cm)
Wei
ght (
g)
Catla catlay = 113.79x - 2362R2 = 0.870
0
500
1000
1500
2000
2500
3000
10 15 20 25 30 35 40 45
Length (cm)
Wei
ght (
g)
Fig. 7.14 : Length-weight relationships of Labeo rohita and Catla catla in Baigul reservoir
Estelar
Reservoir Fisheries………?-264-
It is, therefore, evident that the length-weight relationship of C.
mrigala (Fig. 7.15) was comparatively fairly high (r = 0.957) than the
L. rohita and C. catla (Table 7.4 and 7.5).
Channa striatus
The length-weight relationship of C. striatus can be expressed
by the following equation:
Log w = -3.2949 + 2.0577 log L
r = 0.876
The graphical presentation of this relationship (Fig. 7.15)
revealed a linear relationship in length-weight parameters although
this fish also did not gain required weight as it grows in length. It is
obvious from the above equation that the relationship between length
and weight is perfectly linear (r = 0.876) (Table 7.4 and 7.5).
Labeo gonius
In case of L. gonius the logarithmic regression equation
obtained was as follows:
Low w = -3.0586 + 1.7138 log L
r = 0.954
The graphical presentation of this relationship (Fig. 7.16)
revealed a linear relationship in length-weight parameters although
this fish also did not gain required weight as it grows in length
(r = 0.954). It is obvious from the above equation that the
relationship between length and weight is perfectly linear (r = 0.954)
(Table 7.4 and 7.5).
Estelar
Reservoir Fisheries………?-265-
Cirrhinus mrigalay = 73.104x - 1898.1R2 = 0.915
0
500
1000
1500
2000
2500
3000
3500
20 30 40 50 60 70
Length (cm)
Wei
ght (
g)
Channa striatusy = 114.2x - 1972.3R2 = 0.767
0
500
1000
1500
2000
2500
3000
3500
10 15 20 25 30 35 40 45
Length (cm)
Wei
ght (
g)
Fig. 7.15 : Length-weight relationships of Cirrhinus mrigala andChanna striatus in Baigul reservoir
Estelar
Reservoir Fisheries………?-266-
Labeo goniusy = 51.737x - 1144.5
R2 = 0.910
0
200
400
600
800
1000
1200
20 25 30 35 40 45
Length (cm)
Wei
ght (
g)
Nonopterus notopterusy = 9.5055x - 87.172R2 = 0.758
0
50
100
150
200
250
300
10 15 20 25 30 35 40
Length (cm)
Wei
ght (
g)
Fig. 7.16 : Length-weight relationships of Labeo gonius and Notopterus notopterus in Baigul reservoir
Estelar
Reservoir Fisheries………?-267-
Notopterus notopterus
The regression equation for N. notopterus was estimated to be
as follows:
Log w = -1.9404 + 0.9779
r = 0.871
The graphical presentation of this relationship (Fig. 7.16)
revealed a linear relationship in length-weight parameters although
this fish also did not gain required weight as it grows in length (Table
7.4 and 7.5). Besides, the value of coefficient of regression is also
very high (0.9779), which is indicative of the fact that this fish
became more slender with the increase in body length.
Gudusia chapra
In case of G. chapra the length-weight relationship is presented
by the following equation (Fig. 7.17).
Log w = 0.8005 + 0.1936 log L
r = 0.888
It is obvious that the variation in weight on account of its
growth in length does not conform to the cubic formula for length-
weight relationship (Table 7.4 and 7.5).
Puntius sarana
The length-weight relationship of P. sarana (Fig. 7.17) can be
expressed by the following equation:
Log w = -1.7255 + 0.8609 log L
r = 0.912
Estelar
Reservoir Fisheries………?-268-
Gudusia chapray = 1.5617x + 6.3171R2 = 0.789
0
5
10
15
20
25
30
35
40
45
50
10 12 14 16 18 20 22
Length (cm)
Wei
ght (
g)
Puntius saranay = 7.2599x - 53.148R2 = 0.831
0
20
40
60
80
100
120
140
160
180
10 15 20 25 30
Length (cm)
Wei
ght (
g)
Fig. 7.17 : Length-weight relationships of Gudusia chapra and Puntius sarana in Baigul reservoir
Estelar
Reservoir Fisheries………?-269-
It is, therefore, evident that the length-weight relationship of P.
sarana was more linear (r =0.912) with a fairly high value of
coefficient of determination (r2 =0.831) (Table 7.4 and 7.5).
(G) Strategies for the fisheries management of thereservoir in relation to plankton food web
The present investigation confirms the observations made by
Sugunan (1995) that effective stocking of seed is a prerequisite for
the higher production of fish from the reservoirs. Katiha (2002) found
that higher productivity was the direct outcome of optimum stocking
measures adopted through pen culture.
Fish yield in impoundments depends not only on geo-
morphological and physico-chemical characters, but much more on
manner and level of exploitation (Sugunan, 2000). Considerable work
has been carried out on the fisheries and management of water
bodies in India (Welcomme and Henderson, 1976; Jhingran and
Sugunan, 1990; Cowx, 1994; Sugunan, 1995, 2000; Sugunan and
Sinha, 2000; Sugunan and Katiha, 2004 and Pillay and Katiha,
2007).
The indigenous fish stock levels of Baigul river system are not
adequate to realize the yield potential of the reservoirs. Hence, it is
absolutely necessary to stock the Baigul reservoir with fingerlings of
suitable fish species to maximize production at a sustainable level.
The objectives of stocking are besides aiming at maximizing yield, to
take care of preservation of the biodiversity of the system. Stocking
programme in Baigul reservoir appears to be judicious with stocking
of Indian major carps (rohu, catla and nain (mrigala). Sporadic
occurrence of common carp has been recorded in the catches. The
present yield of reservoirs is moderate.
Estelar
Reservoir Fisheries………?-270-
According to Das et al. (2002), catla should form the dominant
component of stocked fishes. The performance of rohu in reservoirs
especially in oligotrophic ones has not been very encouraging; the
growth of rohu has been found to be impressive in old reservoirs with
rich periphytic flora and fauna. The presence of aquatic vegetation is
particularly suitable for the growth of rohu in Baigul. The reservoir
also contains huge amount of detritus which is a good food resource
for nain. Hence, Indian major carps (rohu, catla and nain) should
form the dominant component of stocking in Baigul reservoir (Plate
19 and 20).
The length of fish seed at the time of stocking is critical in a
reservoir ecosystem to enhance their survival. A length of 10 cm and
above is ideal for quick growth and better survival. About 200-300
fingerlings per hectare may be stocked in large reservoirs and 300-
400 fingerlings in medium and small reservoirs. Average area
[(FRL+DSL)/2] or 60 % of the full reservoir area may be considered
for computing the stocking (Das et al., 2002).Stocking should be
done preferably during post-monsoon (September-October), when the
water level stabilizes and a spurt in zooplankton production occurs.
The Baigul reservoir is stocked with only 4-5 cm fry/fingerlings of
Indian major carps and perhaps it is the main reason for low
recovery of Indian major carps in the catches.
According to Pillay and Katiha (2007), natural breeding and
recruitment of stocked species varies from reservoir to reservoir.
Breeding is no guarantee for successful recruitment, as survival
depends on many factors. In general, natural recruitment is not
dependable in reservoirs, especially in those formed on tributaries,
which warrants stocking on a continuing basis.
Estelar
Reservoir Fisheries………?-271-
Plate 19 : Fishermen spreading drag net forharvesting in reservoir
Plate 20 : Fishermen with the catch
Estelar
Reservoir Fisheries………?-272-
The effects of water-level fluctuations on the reproduction of
fishes and the effectiveness of spawning in reservoirs are reported by
several investigators. The fluctuations of water level in reservoirs are
not always injurious; a deliberate drawdown is sometimes used as a
management tool in reducing stocks of undesirable fishes. Otherwise,
it may be used to establish favorable spawning and feeding areas for
desired species in the impoundments by a practical application of
managed fluctuations. Yakovleva (1969) stated that the fluctuations of
water level at specific periods possibly improve conditions and
increase the breeding efficiency of the fishes. A reduction of water
level in Volgorad reservoir, USSR, 1.5 m to 2.0 m from normal
preserve level in summer led to improving the breeding conditions of
fishes throughout the reservoir in the spring. Allen (1970) has
suggested that the water level in reservoirs must be maintained or
slightly increased during the spawning activity of desirable fishes. A
level between reasonable limits is maintained for about two to three
weeks or until the spawning is completed. This will avoid exposing the
eggs to an extreme low level with a risk of standing, or submerging the
eggs in too deep water. During summer season there is a large draw
dawn of water for irrigation purposes exposing a huge bottom area of
the lake. This season also corresponds with the development of the
brood stock. It is therefore suggested proper maintenance of the water
level in Baigul is very essential.
Though there is a system of mesh regulation, it is not generally
enforced. Strict mesh regulation should be enforced to prevent
exploitation of small sized species. Small-meshed nets could
however, be operated in certain seasons and in certain areas to
exploit the minor carps and minnows under supervision. The best
season for such operation would be the period of low water levels.
Estelar
Reservoir Fisheries………?-273-
The reservoir is leased to a contractor for a period of 3-5 years
for fishing. The highest bidding contractor is required to deposit 25
% of the money immediately and rest is deposited within specified
time given by the Department. The fishermen co-operative societies
taking part in bidding are given preference with 25 % concession.
As the reservoir is surrounded by several villages and colonies,
large scale poaching is a common feature. Attempts to prevent illegal
fishing by the fisheries personnel manning the reservoir or by the
contractor are violently resisted by the poachers. Therefore the
prohibition of destructive methods of catching fish, such as
explosives, poisons, snatches, fishing traps and the taking of fish in
places where at times they congregate has to be strictly avoided.
The fishermen are not the permanent residents of Tarai region,
but they are hired by the contractor from the eastern parts of Uttar
Pradesh, Bihar and West Bengal. They from small parties while
fishing and the income accruing as a result or total fish catch is
distributed among them. The monthly income of a fishermen ranges
between Rs. 2000 to Rs. 3000 per month.
The fishes caught at the reservoir reach different markets such
as, Kichha, Rudrapur, Pantnagar, Haldwani and Baheri through
various retailers-cum vendors. During the peak seasons, however,
the surplus quantity of fish catch, including the trash fish and small
prawns (dried), are transported to the distant markets.
In order to augment fisheries in Baigul reservoir, the state
department has also established a fish-seed production farm of
about 4 ha in the vicinity of this reservoir. The farm has the capacity
to produce 40 lac fish fry/fingerlings per year.
Estelar
Reservoir Fisheries………?-274-
Discussion
Reservoir fisheries are of considerable economic importance in
view of its vast resources, potential employment opportunities and
significance as a source of animal protein in our diet. According to
Jhingran (1989), the average fish yield from the reservoirs has been
extremely low during the last decade or so. This is obviously because
of the prevalent unscientific management practices resulting from
inadequate knowledge of the ecology and production biology of the
reservoir. The fish fauna of Baigul reservoir mainly consists of a rich
assemblage of minor carps and forage fishes, residual cat fishes and
some amount of major carps.
Fish fauna of Baigul reservoir comprised of 36 species of major
carps, minor carps, cat fishes, other fishes and weed fishes. Deorari
(1993) reported 35 fish species belonging to 21 genera of major
carps, minor carps, cat fishes and weed fishes in Dhaura Reservoir.
Balai (2007) recorded 40 species (28 genera) belonging 13 families
representing 5 orders in Jaisamand reservoir. Pathani and Joshi
(2007) identified 39 species of fish belonging to 14 families in Nanak
Sagar reservoir. Deorari (1995) recorded 49 fish species belonging 15
families from Nanak Sagar reservoir.
Rose et al. (2006) reported 22 species belonging to 7 families
contributing to the commercial fisheries of water bodies of Ajmer,
besides the large sized major carps, cat fishes and murrels in
substantial members. Singh et al. (2006) recorded 53 different
species belonging to 7 orders, 18 families and 34 genera from
Mahanadi River. Mohite (2006) recorded 31 species of fishes
belonging to 11 families in reservoirs of Solapur District,
Maharashtra. Sakhare and Joshi (2002) reported the
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occurrence of 20 fish species belonging to 4 orders in Bori reservoir
in Osmanabad district of Maharashtra.
Sultan et al. (2005) reported that the fishes of category A and B
representing major carps of all size groups behaved as a sub-
population; initially major carps were 10.62 % and 0.89 % for the
royalty regime. Category C fishes constituted nearly 38.71 % and
category D (49.77 %) in royalty regime. According to Balai (2007),
fishes of category-I contributed only (4.87 %), category-II (36.44 %),
category-III (15.92 %), category-IV (5.65 %), category-V (24.73 %) and
category-VI contributed (12.38 %) to the total fish production of
Jaisamand reservoir. In the present study class-A contributed
(6.43%), class-B1 (4.48 %), class-B2 (48.94 %), class B3 (7.41%) and
class-C (32.74 %).
Singh and Sharma (1991) have also recorded a large
population of weed fishes (40 %) in Nanak sagar reservoir. Deorari
(1993) recorded that the contribution of weed fishes ranged from
42.1 to 56.6 % in Dhaura reservoir in tarai region. Similarly, the
weed fishes contributed about 57 % of the total fish catch from
Tumaria reservoir in Udham Singh Nagar district (Rawat, 1991). The
weed fishes were also the most important component of reservoir
fishery in Baigul reservoir contributing 32.74 % to the total catch
during study period. The highest catch of weed fishes during winters
in Baigul may be attributed to low temperature in which these fishes
become more sluggish and caught easily. During summer, due to low
water level with high temperature, the fish catch was also high. The
aquatic weeds present in these reservoirs give better place for the
shelter of the weed fishes. Labeo gonius is most dominant fishery of
this reservoir which contributed 40.83 % in Baigul to the total catch.
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In the present investigation, the contribution of important
fishes/groups to the total fish production was calculated as follows:
Catla catla (0.58 %), Cirrhinus mrigala (2.09 %), Labeo rohita (2.17
%), Channa striatus (2.86 %) and other fishes (7.41 %). Balai (2007)
recorded monthly fish production of Catla catla as 49.59%, Cirrhinus
mrigala (6.74 %), Labeo rohita (1.68 %), Wallago attu (1.34 %),
Channa marulius (0.09 %) and other fishes (36.66 %) in Jaisamand
reservoir; major carps contributed 58.01 %, cat fishes 5.33 % and
other fishes 36.66 %. In the present study major carps contributed
6.43 %, cat fishes (4.48 %), minor carps (48.94 %) and weed fishes
(32.74 %).
As per the report of Sakhare and Joshi (2003) the potential
yield in the reservoirs of the districts of Maharashtra was estimated
at 5432.28 tones based on stocking level of 9733 lakh fish seed.
Deorari (1993) have observed the limnological features of the
Dhaura reservoir and indicated the possibility of a better yield of
fish. The moderate temperature of water (15.5ºC to 34.5°C) is
favorable for good growth of plankton. Similarly the pH values (7.2 to
8.6) are also favorable for a high rate of production. Baigul reservoir
with almost similar limnological profiles appears to be a favorable
habitat for fish growth. Rawat (1991) has reported an average fish
production of 21.30 kg/ha for Tumaria reservoir whereas Singh and
Sharma (1991) reported a production of 10-14 kg/ha for Nanak
Sagar reservoir; both reservoirs are located in the tarai region.
Development of fisheries in a particular reservoir directly
benefits a large number of people engaged in different activities. But
the fish production from these reservoirs is currently much below
than their potential. In Indian reservoirs, the fish yield ranges from a
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minimum of 2.5 kg/ha/yr to a maximum of 120 kg/ha/yr (Jyoti et
al., 2004). Some of the reasons for low yield are lack of
understanding of reservoir ecology, paucity of indigenous fish fauna,
faulty stocking and over exploitation. Sugunan and Sinha (2000)
emphasized that the fish productivity is related to morphometric,
hydrological and ecological features of particular water because the
yield is partly a function of biotic and abiotic factors influencing
production process of that ecosystem. The low fish production (28.34
kg/ha) from Baigul reservoir in 2004 could be attributed, among
other factors, to inadequate stocking, and irrational exploitation. In
Baigul reservoir the dominance of weed fishes might have interfered
with the growth of major carps. Besides competing for food and
space, the weed fishes provide a forage base for predatory cat fish
populations which in turn affect the recruitment potential of
economic carps as well.
The commercial fishing in Baigul is carried out mostly from
October to June, using traditional types of gears viz., gill net, hooks
and lines, drag net, triangular net, cast net and rod and line. The
fishing methods are designed to suit the local conditions and the
availability of different fishes in the reservoir. Some of the gears are
very specific and are designed for a particular species although most
of them take multispecies catches. The gill nets of different sizes
were effectively used during the periods of maximum water level to
capture valuable fish species like minor and major carps and at
fishes. Simultaneously, the hooks and lines were also used.
Drag nets were frequently used during May and June in
shallow areas with maximum catch efficiency. The majority of fishes
trapped by the drag net were weed fishes. Because of a very low
market price of the weed fishes caught by the drag nets, this gear is
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economically less viable. The highest catches of fishes (62614 kg)
were obtained by drag net during present investigation. The
contribution of drag net was 31.4 %. Triangular and cast nets were
operated in both the years, to catch small prawns, weed fishes,
major carps, minor carps and cat fishes. The contribution of cast
and triangular net was 14.28 % and 6.13 % and total catch was
28470 and 12227 kg in the Baigul reservoir. The use of rod and lines
were occasionally observed in summer for catching cat fishes. The
total catch of line and rod and hook line was 3988 and 2000 kg
during study period. The contribution of these nets was very low.
The majority of carps are omnivores feeding on plankton.
However, during larval stages zooplankton constitutes the main food
of all carps. Large populations of weed fishes must be depleting the
zooplankton population in the Baigul reservoir. Consequently the
lack of adequate zooplankton feed in the reservoir could be the major
factor for the low population of major carps in general, and Catla
catla fishery in particular as the latter is a zooplanktophagous fish.
Standing water bodies support a wide range of indigenous fish
species in the dry season and make a crucial contribution to fishery
production (Hoggarth et al., 1999 and Craig et al., 2004), with G.
chapra an important element of the catch. A similar observation was
found in the present investigation.
The causes of success or failure of particular fish or groups of
fishes in man-made reservoir are many. The changed,
ecomorphological features, availability of food, spawning success,
survival and recruitment of young to the fishable stock, employment
of suitable gears, season of fishing etc. are some of the factors that
contribute to the success or failure of the fishery. Bhatnagar (1963)
and Rajagopal (1969) have observed that the decline of fishery in
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Tungabhadra reservoir could be attributed to elimination of the
juveniles by the non-selective gears like shore seine and intensive
exploitation of natural stock by gill nets.
Jhingran (1991) has suggested that minimum mesh size
permitted for gill nets should not be less than 30 mm. According to
David and Rajagopal (1978) the gill nets with mesh sizes of 40, 50
and 70 mm were found to be more effective for commercial fishing in
Tungabadhara, Govind sagar and Hirakund reservoirs.
Krishnamurthy et al. (1964) pointed out that in Mettur and
Krishnarajsagar reservoirs, nets of larger mesh sizes (> 50 mm) were
used to catch the commonly occurring carps and cat fishes. Similar
patterns of use of gill nets have been observed in Baigul reservoir.
Deorari (1993) pointed out that in Dhaura reservoir, gill nets of
larger mesh sizes (> 50 mm) were used to catch the commonly
occurring commercial fishes viz. carps, cat fishes and some weed
fishes. Similar patterns of use of gill nets (50 – 75 mm mesh size)
have been observed in Baigul reservoirs.
In the present investigations, a sharp decline in water level
could have reduced the fishing season and lead to concentrated
fishing in summer, resulting in a total exploitation of the fishery. The
average size of carps and cat fishes, therefore, dropped below the
marketable size and the catch per unit effort was reduced. Thus,
fishery in the Baigul reservoir predominantly yielded small-sized
herbivorous forage fish and weed fish. The small fish are sun- dried
and marketed while the larger ones are transported to the nearby
markets.
Phytoplankton population in Baigul reservoir is represented by
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the extensive blooms of blue green alga, Microcystis aeruginosa
which is not directly utilized by the existing fish species. Obviously,
it does not enter the food chain as a result of which the zooplankton
population in Baigul reservoir is low.
The major aims of the stocking program in the reservoir are
biological control and balancing a depleted fish population.
According to Luu (1998) and Luong et al. (2004), development of
these stocked species relies on natural food within the reservoir
being ecologically sound and most likely more sustainable.
Consequently, the stocking needs to compensate for recruitment over
fishing, and to maintain the fisheries productivity of a water body at
the highest possible level (Welcomme, 1998). The findings of this
study and results of fish stocking in the reservoir are positively
related to changes in population.
The perusal of Table 7.4 and 7.5 reveals that relationship
between length and weight differed significantly (r = 0.871 to 0.957);
P < 0.01 in different fishes. Based on the coefficient of determination,
more than 90 % of variations in weight in Cirrhinus mrigala and
Labeo gonius and more than 80 % in Catla catla were attributable to
the variation in length in Baigul reservoir. Similar results were also
reported by Rao et al., (1991), De and Dutta (1990), Reddy and Rao
(1992), Singh (1994), Ujjania and Sharma (1999), Ujjania (2003) and
Rose et al. (2006) reported such relationship in certain freshwater
fishes. Ujjania (2003) also calculated them and observed ‘b’ values
from 2.853 to 4.06 and V values of 0.458 to 0.947 (length range 25
to 75 cm) from Surwania dam (small water) body of Banswara,
Rajasthan. Reddy and Rao (1992) reported growth parameters in
freshwater fishes. The results obtained in the present study are
comparable to those obtained the above studies.
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The growth exponent values of present study of Labeo rohita
were found comparable to those reported by Singh (1994) from lake
Jaisamand, Udaipur and Ujjania (2003) from Surwania Dam,
Banswara. The values of regression coefficients (0.1936 to 2.0577)
indicated that the growth rates of the fish were lesser than the cube
of their length. There are also reports of significant deviation of
length-weight relationship from the cube law in the fishes (Sultan,
1981; Gowda et al., 1987; Sivakami, 1987; Kulshreshta et al., 1993;
Pandey, 1995; Mitra, 2001 and Nath et al. 2006). Agarwal and
Saxsena (1979) recorded the value of 2.18 for Catla catla. Basheer et
al., (1993) observed ‘b’ value for Channa punctatus to be 2.9419.
Hasmana and Lal (1993) reported that the value of ‘b’ ranged from
2.5 to 3.9.
The fishery of Baigul reservoir is mainly comprised by medium
sized carp Labeo gonius. Weed fishes, catfishes and minor carps
comprise the rest of the fishery. Major carps contribute only 6.43 %
to the total fish catch. The dominance of weed fishes and the
presence of catfishes in reasonable amount are apparently the major
factors in preventing the development of major carps in sizeable
numbers. It is recommended that L. gonius should be stocked in the
reservoir to increase its production as it has good recruitment rate.Estelar
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