302
the annual fi sh yield from the Beel was 308.45 mt
during 2009–2010 and 301.55 mt during 2010–
2011. The yield trend appeared to show a dwindling trend (Kar 2012 ). Inconsistent trend of
natural recruitment in such waterbodies (Dey
1981 ) coupled with higher catches in the turbid
water might be the causative factor for higher
yield during the fi rst year. The forage fi sh containing mainly the cyprinids and chandids, which
constitute the bulk landing, could have gained
ascendance over the predatory catfi sh to add further reasons to such propositions. The fi sh yield
from Sone Beel appeared to be low as compared
to 250 kg/ha obtained by Vaas and Schurman
( 1949 ) in some tropical FWs of Java. Further,
Jhingran and Tripathi ( 1969 ) had recorded the
range of fi sh yield from the Indian reservoirs to
be as low as 6–7 kg/ha/year.
The constant deposition of ‘silt’ exposes the
fi shes in the shallower areas to shortage of living
space (Welcomme 1979 ). This has an impact on
the production through an eventual diminution
of the water spread area (Kar 1990 ). Moreover,
the lake soil with pH 5.0–5.9, organic carbon
0.25–1.74 % and available phosphorus 0.15–
1.93 % and water with pH 6.0–7.9 and dissolved
oxygen 2.4–5.9 mg/l were not very suitable for
fi sh production (Banerjea 1967 ; Michael 1969 ).
Also, dense strands of aquatic macrophytes,
often known to bind up nutrient materials, thus
could result in reduction of natural food availability for the fi sh and lead to poor fi sh yield
(Bennet 1962 ). Further, as an attempt to increase
fi sh yield (Fernando and Furtado 1975 ) by introduction of Cyprinus carpio into the Beel, there
has been adverse effect on the autochthonous
ichthyodenizens of the Beel which could well
account for overall poor yield from Sone Beel
(Dey and Kar 1990 ).
Of the 70 fi sh species, only Puntius chola,
Parambassis sp. , Chanda nama and Gudusia
chapra contained annual average yield (ARY) of
more than 10 %. Amongst them, Puntius chola,
the minnow, contributed to the bulk of the fi sh
landing from the Beel registering an average
ARY of 21.39 and 27.82 % during the study
periods, thus portraying its signifi cant contribution to the overall fi sh yield from the Beel. It is
signifi cant to note here that the Indian major
carps (IMC) of the Beel consist of fi ve distinct
species depicting an average ARY (as a group)
of 21.39 and 27.82 % during study periods. Of
them, Labeo rohita alone portrayed an average
ARY of 0.23 and 0.24 % during the study period,
which, incidentally, was the highest amongst the
other species of the group. Non-judicious and
irrational harvest of the juvenile IMCs in greater
proportions has caused imbalance in the IMC
fi shery of the wetland culminating in overall
poor contribution of this group in the total fi sh
yield of the Beel (wetland). Concomitant to
IMCs, the Indian shad, Hilsa(Tenualosa) ilisha,
with an average ARY of 0.04 % (which is admittedly low) revealed a single run in Sone Beel
during the monsoon against two runs in other
waterbodies of India. Hilsa is generally more
prevalent in the NE, SE and SW zones of the
Beel, probably, due to fl uviatile nature of these
zones. Indeed, the day-in and day-out fi shing
operations could spare very little scope for the
recruited shads to make their return journey.
Cyprinus carpio was the only exotic carp
recorded in the Beel with an average ARY of
0.155 %. Amongst the other carps and minnows,
Puntius sarana, Rasbora daniconius and
Salmophasia bacaila depicted average ARY of
0.085, 0.63 and 0.93 %, respectively. Amongst
the cobitids, which signifi cantly include the
‘ornamental fi shes’, Botia dario accounted for
0.485 % as average ARY, while Lepidocephalichthys guntea dominated the cobitids with an
average ARY of 0.97 %.
The ‘C’-class fi sh (Swingle 1950 ) of the Beel
usually contains average ARY of 1.75 and
4.83 % collectively. However, of all the predatory fi shes, Wallago attu alone contributed to an
average ARY of 2.94 %, as revealed from the
study (Kar 1990 ). Nevertheless, Mystus vittatus
dominated the predatory fi shes with an average
ARY of 7.75 %. Fishes like Sperata seenghala,
Mystus cavasius, Ompok bimaculatus and
Eutropiichthys vacha portrayed high commercial
value and depicted average ARY of 0.075, 0.03,
0.77 and 0.09 %, respectively. The live catfi shes
include Clarias batrachus and Heteropneustes
fossilis which exhibited average ARY of 0.11
20 Wetlands of India
the annual fi sh yield from the Beel was 308.45 mt
during 2009–2010 and 301.55 mt during 2010–
2011. The yield trend appeared to show a dwindling trend (Kar 2012 ). Inconsistent trend of
natural recruitment in such waterbodies (Dey
1981 ) coupled with higher catches in the turbid
water might be the causative factor for higher
yield during the fi rst year. The forage fi sh containing mainly the cyprinids and chandids, which
constitute the bulk landing, could have gained
ascendance over the predatory catfi sh to add further reasons to such propositions. The fi sh yield
from Sone Beel appeared to be low as compared
to 250 kg/ha obtained by Vaas and Schurman
( 1949 ) in some tropical FWs of Java. Further,
Jhingran and Tripathi ( 1969 ) had recorded the
range of fi sh yield from the Indian reservoirs to
be as low as 6–7 kg/ha/year.
The constant deposition of ‘silt’ exposes the
fi shes in the shallower areas to shortage of living
space (Welcomme 1979 ). This has an impact on
the production through an eventual diminution
of the water spread area (Kar 1990 ). Moreover,
the lake soil with pH 5.0–5.9, organic carbon
0.25–1.74 % and available phosphorus 0.15–
1.93 % and water with pH 6.0–7.9 and dissolved
oxygen 2.4–5.9 mg/l were not very suitable for
fi sh production (Banerjea 1967 ; Michael 1969 ).
Also, dense strands of aquatic macrophytes,
often known to bind up nutrient materials, thus
could result in reduction of natural food availability for the fi sh and lead to poor fi sh yield
(Bennet 1962 ). Further, as an attempt to increase
fi sh yield (Fernando and Furtado 1975 ) by introduction of Cyprinus carpio into the Beel, there
has been adverse effect on the autochthonous
ichthyodenizens of the Beel which could well
account for overall poor yield from Sone Beel
(Dey and Kar 1990 ).
Of the 70 fi sh species, only Puntius chola,
Parambassis sp. , Chanda nama and Gudusia
chapra contained annual average yield (ARY) of
more than 10 %. Amongst them, Puntius chola,
the minnow, contributed to the bulk of the fi sh
landing from the Beel registering an average
ARY of 21.39 and 27.82 % during the study
periods, thus portraying its signifi cant contribution to the overall fi sh yield from the Beel. It is
signifi cant to note here that the Indian major
carps (IMC) of the Beel consist of fi ve distinct
species depicting an average ARY (as a group)
of 21.39 and 27.82 % during study periods. Of
them, Labeo rohita alone portrayed an average
ARY of 0.23 and 0.24 % during the study period,
which, incidentally, was the highest amongst the
other species of the group. Non-judicious and
irrational harvest of the juvenile IMCs in greater
proportions has caused imbalance in the IMC
fi shery of the wetland culminating in overall
poor contribution of this group in the total fi sh
yield of the Beel (wetland). Concomitant to
IMCs, the Indian shad, Hilsa(Tenualosa) ilisha,
with an average ARY of 0.04 % (which is admittedly low) revealed a single run in Sone Beel
during the monsoon against two runs in other
waterbodies of India. Hilsa is generally more
prevalent in the NE, SE and SW zones of the
Beel, probably, due to fl uviatile nature of these
zones. Indeed, the day-in and day-out fi shing
operations could spare very little scope for the
recruited shads to make their return journey.
Cyprinus carpio was the only exotic carp
recorded in the Beel with an average ARY of
0.155 %. Amongst the other carps and minnows,
Puntius sarana, Rasbora daniconius and
Salmophasia bacaila depicted average ARY of
0.085, 0.63 and 0.93 %, respectively. Amongst
the cobitids, which signifi cantly include the
‘ornamental fi shes’, Botia dario accounted for
0.485 % as average ARY, while Lepidocephalichthys guntea dominated the cobitids with an
average ARY of 0.97 %.
The ‘C’-class fi sh (Swingle 1950 ) of the Beel
usually contains average ARY of 1.75 and
4.83 % collectively. However, of all the predatory fi shes, Wallago attu alone contributed to an
average ARY of 2.94 %, as revealed from the
study (Kar 1990 ). Nevertheless, Mystus vittatus
dominated the predatory fi shes with an average
ARY of 7.75 %. Fishes like Sperata seenghala,
Mystus cavasius, Ompok bimaculatus and
Eutropiichthys vacha portrayed high commercial
value and depicted average ARY of 0.075, 0.03,
0.77 and 0.09 %, respectively. The live catfi shes
include Clarias batrachus and Heteropneustes
fossilis which exhibited average ARY of 0.11
20 Wetlands of India