583
D. Kar, Wetlands and Lakes of the World,
DOI 10.1007/978-81-322-1023-8_27, © Springer India 2013
27.1 Introduction
‘Fish catching devices’, popularly called ‘fi shing
gears and crafts’, are the implements to harvest
fi shes from a waterbody. They exhibit bewildering
diversity globally, nationally, regionally and locally.
Variations also exist according to fi sh type, fi shermen type and season type. The effi cacies of the
gears, in the present treatise, have been determined
on the basis of fi sh catch (kg/person/gear/hour:
CPGH) (Dey 1981 ; Kar 2007a , b , c ), while wherever necessary, % of fi shing communities operating
a particular kind of gear has been evaluated from
fi eld survey. Attempts have been made to calculate
Mechanisation Index (MI) (Gadgil and Reddy
1989 ), Hanging Coeffi cient (HC) and Niche’ Width
(NW) (Smith 1986 ) from the fi eld data (Kar and
Dey 1991 , 1993a , b , 1996 ; Kar et al. 1999 ). ANOVA
tests, wherever done, indicated that there exists
highly signifi cant differences between the different
kinds of gears with regard to their CPGH (Kar and
Dey 1996 ; Kar 2007a , b , c ).
27.2 General Fish Catching
Devices in Wetlands
The wetland ecosystem is of varied type exhibiting different ecological, limnological and biological characteristics during different seasons. It
also exhibits different zones and niches according to depth distribution. As such, this type of eco
set-up enables dwelling by a rich diversity of
fi shes in the wetland. Hence, fi shes, which are the
economically important dwellers in a wetland,
are distributed according to depth, seasons, food
availability, migratory habit, etc. Accordingly,
diverse types of fi shing gears have evolved keeping pace with the rich diversity of fi shes, which
ultimately, perhaps, culminated in specialisations
and specifi city of the fi shing gears to fi sh type,
fi shermen type and season type. Thus, in a typical
freshwater wetland, longline gears are used
mainly to catch the bottom-dwelling fi shes; gill
nets are used mainly to haul the IMCs, Wallago
attu ; trawls are used mainly to catch the trash
fi shes; encircling gears are operated mainly for
catching large school of fi shes; and so on.
However, operation of enormous encircling gears
(locally called ‘Mahajal’ in India and Bangladesh)
has been having detrimental effect on the fi sh
population in a wetland, mainly because of its
ability to almost totally sieve out the fi shes from
a locality including the juveniles.
27.3 Wetland Fish Catching
Devices Exemplifi ed from
a Typical Wetland in Asia
The fi sh catching devices play important role in
the commercial exploitation of the wetland and
riverine fi sheries of the region. Various types of
fi shing gears are operated in lentic systems. An
account of the fi shing gears and crafts in Sone
Beel (the biggest wetland in Assam), as an example of fi sh catching devices from a typical wetland in Asia, is given below.
27
Fish Catching Devices in
the Wetlands
D. Kar, Wetlands and Lakes of the World,
DOI 10.1007/978-81-322-1023-8_27, © Springer India 2013
27.1 Introduction
‘Fish catching devices’, popularly called ‘fi shing
gears and crafts’, are the implements to harvest
fi shes from a waterbody. They exhibit bewildering
diversity globally, nationally, regionally and locally.
Variations also exist according to fi sh type, fi shermen type and season type. The effi cacies of the
gears, in the present treatise, have been determined
on the basis of fi sh catch (kg/person/gear/hour:
CPGH) (Dey 1981 ; Kar 2007a , b , c ), while wherever necessary, % of fi shing communities operating
a particular kind of gear has been evaluated from
fi eld survey. Attempts have been made to calculate
Mechanisation Index (MI) (Gadgil and Reddy
1989 ), Hanging Coeffi cient (HC) and Niche’ Width
(NW) (Smith 1986 ) from the fi eld data (Kar and
Dey 1991 , 1993a , b , 1996 ; Kar et al. 1999 ). ANOVA
tests, wherever done, indicated that there exists
highly signifi cant differences between the different
kinds of gears with regard to their CPGH (Kar and
Dey 1996 ; Kar 2007a , b , c ).
27.2 General Fish Catching
Devices in Wetlands
The wetland ecosystem is of varied type exhibiting different ecological, limnological and biological characteristics during different seasons. It
also exhibits different zones and niches according to depth distribution. As such, this type of eco
set-up enables dwelling by a rich diversity of
fi shes in the wetland. Hence, fi shes, which are the
economically important dwellers in a wetland,
are distributed according to depth, seasons, food
availability, migratory habit, etc. Accordingly,
diverse types of fi shing gears have evolved keeping pace with the rich diversity of fi shes, which
ultimately, perhaps, culminated in specialisations
and specifi city of the fi shing gears to fi sh type,
fi shermen type and season type. Thus, in a typical
freshwater wetland, longline gears are used
mainly to catch the bottom-dwelling fi shes; gill
nets are used mainly to haul the IMCs, Wallago
attu ; trawls are used mainly to catch the trash
fi shes; encircling gears are operated mainly for
catching large school of fi shes; and so on.
However, operation of enormous encircling gears
(locally called ‘Mahajal’ in India and Bangladesh)
has been having detrimental effect on the fi sh
population in a wetland, mainly because of its
ability to almost totally sieve out the fi shes from
a locality including the juveniles.
27.3 Wetland Fish Catching
Devices Exemplifi ed from
a Typical Wetland in Asia
The fi sh catching devices play important role in
the commercial exploitation of the wetland and
riverine fi sheries of the region. Various types of
fi shing gears are operated in lentic systems. An
account of the fi shing gears and crafts in Sone
Beel (the biggest wetland in Assam), as an example of fi sh catching devices from a typical wetland in Asia, is given below.
27
Fish Catching Devices in
the Wetlands