233
species of fi shes from NE India. Nevertheless,
Nath and Dey ( 1997 ) recorded 131 species of
fi shes from the drainages in Arunachal Pradesh
alone. Sen ( 2000 ) comprehensively compiled a list
of 267 species of fi shes from NE India. Further,
according to Sen ( 2000 ), of the c 806 species of
fi shes inhabiting the freshwaters of India (Talwar
and Jhingran 1991 ), the NE region of India is represented by 267 species belonging to 114 genera
under 38 families and 10 orders. This is c 33.13 %
of the total Indian FW fi shes. Of the 267 species,
Cypriniformes dominates with c 145 species
followed by Siluriformes (72), Perciformes
(31), Clupeiformes (7), Anguilliformes (3),
Cyprinodontiformes (3), Osteoglossiformes (2),
Synbranchiformes (2), Syngnathiformes (1) and
Tetraodontiformes (1). Kar ( 2003a ) reported the
occurrence of 133 species of fi shes through a pilot
survey conducted in 19 rivers spread in Barak
drainage (Assam), Mizoram and Tripura. Kar
( 2005a ), further, reported the occurrence of 103
species of fi shes through an extensive survey conducted in six principal rivers in Barak Valley
(Assam), Mizoram and Tripura. Kar ( 2007a , b ),
Kar and Sen ( 2007 ) and Kar et al. ( 2008 , 2009 ,
2010, 2011 , 2012) have done detailed study on the
biodiversity of fi shes in Northeast India with particular reference to Barak drainage, Mizoram and
Tripura. Kar ( 1990 , 1996 , 2000a , b , 2007a , b ,
2008, 2010 , 2012a , b , c ) worked on the fi sh diversity and their yield in a large number of wetlands
in India.
Notwithstanding the above, studies on the fi sh
assemblage structure and their habitat requirements
in the lotic (streams, rivers, etc.) and lentic (wetlands, lakes, etc.) of Northeast India are scanty. Few
initiatives have started in South India (Arunachalam
et al. 1988 ). A novel approach related to the study of
fi sh assemblage structure and species inventory and
habitat requirement of individual ichthyospecies in
the assemblage have been done by the present
author in different parts of India.
15.5.1.2 Methodology
General survey of the fi sh biodiversity and habitat parameters was done using standard procedures (Armontrout 1990 ). Also, the NBFGR
Manual ( 2000 ) was consulted for studying the
habitat parameters. Headwater to downstream
studies were based on the River Continuum
Concept (Vannote et al. 1980 ). Spatial heterogeneity of river channel across small to large spatial
scales (Forman and Godran 1980 ) and longitudinal (upstream vs. downstream) and lateral (stream
margin/mid-channel) dimensions was studied.
In the present study, fi sh samples were collected through experimental fi shing using cast
nets (dia. 3.7 m and 1.0 m), gill nets (vertical
height 1.0–1.5 m; length 100–150 m), drag nets
(vertical height 2.0 m), triangular scoop nets
(vertical height 1.0 m) and a variety of traps.
Camoufl aging technique was also used to catch
the fi shes. Fishes have been preserved, at fi rst, in
concentrated formaldehyde in the fi eld itself and
then in 40 % formaldehyde in water (formalin).
Fishes have been identifi ed after standard literature (Day 1878 , 1889 ; Shaw and Shebbeare 1937 ;
Misra 1959 ; Menon 1974 , 1999 ; Talwar and
Jhingran 1991 ; Jayaram 1981 , 1999 , 2003 , 2010 ;
Kar 2007a , b ). Yield statistics were extrapolated
(Dey and Kar 1990 ; Kar 1990 ) from daily catch
statistics recorded at the landing stations (FAO
1974 ), while the trend and cyclic variations were
constructed by applying 12-month moving average method (Coxton and Cowden 1950 ; Kar and
Dey 2000 ).
15.5.2 Ichthyogeography
Zoogeography is that branch of science which
deals with the distribution of animals including
the history of their occurrence on earth. The ichthyofauna of India could be broadly classifi ed
under two groups on the basis of their distribution, namely,
(a) Freshwater (FW)
(b) Marine
The third category, namely,
(c) The estuarine forms could be either of the
two in origin.
15.5.2.1 Ichthyogeography
in General
The land masses of the world may conveniently be
divided into the following realms (Darlington 1957 )
15.5 Wetland Fishes
species of fi shes from NE India. Nevertheless,
Nath and Dey ( 1997 ) recorded 131 species of
fi shes from the drainages in Arunachal Pradesh
alone. Sen ( 2000 ) comprehensively compiled a list
of 267 species of fi shes from NE India. Further,
according to Sen ( 2000 ), of the c 806 species of
fi shes inhabiting the freshwaters of India (Talwar
and Jhingran 1991 ), the NE region of India is represented by 267 species belonging to 114 genera
under 38 families and 10 orders. This is c 33.13 %
of the total Indian FW fi shes. Of the 267 species,
Cypriniformes dominates with c 145 species
followed by Siluriformes (72), Perciformes
(31), Clupeiformes (7), Anguilliformes (3),
Cyprinodontiformes (3), Osteoglossiformes (2),
Synbranchiformes (2), Syngnathiformes (1) and
Tetraodontiformes (1). Kar ( 2003a ) reported the
occurrence of 133 species of fi shes through a pilot
survey conducted in 19 rivers spread in Barak
drainage (Assam), Mizoram and Tripura. Kar
( 2005a ), further, reported the occurrence of 103
species of fi shes through an extensive survey conducted in six principal rivers in Barak Valley
(Assam), Mizoram and Tripura. Kar ( 2007a , b ),
Kar and Sen ( 2007 ) and Kar et al. ( 2008 , 2009 ,
2010, 2011 , 2012) have done detailed study on the
biodiversity of fi shes in Northeast India with particular reference to Barak drainage, Mizoram and
Tripura. Kar ( 1990 , 1996 , 2000a , b , 2007a , b ,
2008, 2010 , 2012a , b , c ) worked on the fi sh diversity and their yield in a large number of wetlands
in India.
Notwithstanding the above, studies on the fi sh
assemblage structure and their habitat requirements
in the lotic (streams, rivers, etc.) and lentic (wetlands, lakes, etc.) of Northeast India are scanty. Few
initiatives have started in South India (Arunachalam
et al. 1988 ). A novel approach related to the study of
fi sh assemblage structure and species inventory and
habitat requirement of individual ichthyospecies in
the assemblage have been done by the present
author in different parts of India.
15.5.1.2 Methodology
General survey of the fi sh biodiversity and habitat parameters was done using standard procedures (Armontrout 1990 ). Also, the NBFGR
Manual ( 2000 ) was consulted for studying the
habitat parameters. Headwater to downstream
studies were based on the River Continuum
Concept (Vannote et al. 1980 ). Spatial heterogeneity of river channel across small to large spatial
scales (Forman and Godran 1980 ) and longitudinal (upstream vs. downstream) and lateral (stream
margin/mid-channel) dimensions was studied.
In the present study, fi sh samples were collected through experimental fi shing using cast
nets (dia. 3.7 m and 1.0 m), gill nets (vertical
height 1.0–1.5 m; length 100–150 m), drag nets
(vertical height 2.0 m), triangular scoop nets
(vertical height 1.0 m) and a variety of traps.
Camoufl aging technique was also used to catch
the fi shes. Fishes have been preserved, at fi rst, in
concentrated formaldehyde in the fi eld itself and
then in 40 % formaldehyde in water (formalin).
Fishes have been identifi ed after standard literature (Day 1878 , 1889 ; Shaw and Shebbeare 1937 ;
Misra 1959 ; Menon 1974 , 1999 ; Talwar and
Jhingran 1991 ; Jayaram 1981 , 1999 , 2003 , 2010 ;
Kar 2007a , b ). Yield statistics were extrapolated
(Dey and Kar 1990 ; Kar 1990 ) from daily catch
statistics recorded at the landing stations (FAO
1974 ), while the trend and cyclic variations were
constructed by applying 12-month moving average method (Coxton and Cowden 1950 ; Kar and
Dey 2000 ).
15.5.2 Ichthyogeography
Zoogeography is that branch of science which
deals with the distribution of animals including
the history of their occurrence on earth. The ichthyofauna of India could be broadly classifi ed
under two groups on the basis of their distribution, namely,
(a) Freshwater (FW)
(b) Marine
The third category, namely,
(c) The estuarine forms could be either of the
two in origin.
15.5.2.1 Ichthyogeography
in General
The land masses of the world may conveniently be
divided into the following realms (Darlington 1957 )
15.5 Wetland Fishes