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CHAPTER I
GENERAL INTRODUCTION
1.1 Background
Cyprinus carpio Linnaeus (1758) is one of the commercially important and oldest
domesticated freshwater fish in the world. Cyprinus carpio is more popularly known as
the common carp, German carp, or European carp. It belongs to the order Cypriniformes
and the family Cyprinidae. The family Cyprinidae (cyprinids) is one of the largest
families of freshwater teleost fish having seven subfamilies, 220 genera and
approximately 20,000 described species (Howes, 1991). The native range of common
carp extends from Japan (Mabuchi et al., 2005) to the River Danube in Eastern Europe
(Balon, 1995a). Human activities associated with the cultivation and domestication of
carp for food and for ornamental characteristics, however, have introduced common
carp into many new waterways throughout Asia, Africa, the Americas, Oceania,
Australia and New Zealand (Koehn et al., 2004). Now the species comprises different
genetic variants in different parts of the world (Chistiakov and Voronova, 2009).
In India the C. carpio communis (Chinese stock) popularly called scale carp that
was introduced in 1957 is found in all over country (Reddy, 2005). In has been
hypothesized that certain micro-mutations may or have created changes in their genetic
constitution. The molecular markers have immense help in finding out the differences in
the species and to determine genetic distance between individuals or populations. In the
current study an attempt has been made to evaluate the genetic variability of common
carp in India and differences of proximate compositions among the genetic variants if
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any. This will help in the understanding of the genetic variability and proximate
biochemical compositions of exotic fish species Cyprinus carpio in India and Northeast
India in particular.
1.2 Taxonomy of Cyprinus carpio
Linnaeus first described Cyprinus carpio in 1758. Cyprinus carpio is
taxonomically a confusing species. According to the review by Barus et al., (2002) it
remains without a holotype and was described ‘using specimens from pond culture,
designating Europe as the terra typica. Presuming that all domestic European forms
originated as wild carps from the Danube, specimens from the Danube River can be
considered as typical’. Most of the confusion comes from giving quasi taxonomic
names to feral specimens or populations. For example, Zhou & Chu (1986) list 12
species from Yunan Province, China, and Barus et al., (2002) cite more than 30
synonyms and over 10 sub-species, varieties and morphs from across its range. This
compares with those given by Kottelat (1997) of 15 sub-species and eight varieties and
morphs. Using the best data available, Barus et al., (2002) concluded that only three
sub-species of Cyprinus carpio can be recognized which are the European and central
Asian common wild carp, Cyprinus carpio carpio L., the East Asian common wild carp,
Cyprinus carpio haematopterus Temminck & Schlegel, 1846 and the south-east Asian
wild carp, C. carpio viridiviolaceus Lacepe de. None of the data are convincing, nor is
the claimed occurrence of Cyprinus carpio haematopterus throughout East Asia from
the Amur River across China, Korea and Japan. More than 200 years earlier, the first
colonies of the Portuguese and the Dutch were established at Nagasaki. Common carp
culture was by then widespread in the European homelands of these colonists and it is,
therefore, possible that the common carp was introduced by them to Japan (Balon,
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1995b, 2004). Tableware decorated with common carp images once belonging to these
early Dutch colonists can be seen on display in a Nagasaki Museum (Balon, 1995b).
While Cyprinus carpio haematopterus became the nominal sub-species for China, it is
possible that these were feral descendants of domesticated European fish that escaped or
were introduced in Japan and possibly China. This taxonomic confusion may be
resolved by molecular markers but it would be more prudent to consider the wild
ancestor of the common carp as a single species, Cyprinus carpio, widely distributed
from the Danube to the Amur river, as feral forms elsewhere and as naturalized
wherever suitable conditions prevail (Lever, 1996). Common carp are closely related to
goldfish. The two are often confused, and the two species are mainly distinguished by
the presence of two pairs of barbels on either side of the common carp’s mouth (Curtin,
2001).
Figure 1.1. Morphology of Common carp (adapted from Haynes, 2009)
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Figure 1.2. Wild common carp (a) and its feral form (b) from Danube delta in 1990
(from Antipa, 1909; Balon, 2004)
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Figure 1.3. Photographs of Cyprinus carpio communis found in India
Systematic Position of Cyprinus carpio
Domain: Eukaryota - Whittaker & Margulis,1978 - eukaryotes
Kingdom: Animalia - Linnaeus, 1758 - animals
Subkingdom: Bilateria - (Hatschek, 1888) Cavalier-Smith, 1983
Branch: Deuterostomia - Grobben, 1908
Infrakingdom: Chordonia - (Haeckel, 1874) Cavalier-Smith, 1998
Phylum: Chordata - Bateson, 1885 - Chordates
Subphylum: Vertebrata - Cuvier, 1812 - Vertebrates
Infraphylum: Gnathostomata - Auct. - Jawed Vertebrates
Superclass: Osteichthyes - Huxley, 1880 - Bony Fishes
Class: Osteichthyes - Huxley, 1880 - Bony Fishes
Subclass: Actinopterygii - Ray-Finned Fishes
Infraclass: Actinopteri
Cohort: Clupeocephala
Order: Cypriniformes
Family: Cyprinidae - Minnows and Carps
Subfamily: Cyprininae
Genus: Cyprinus - Linnaeus, 1758
Specific name: C. carpio - Linnaeus, 1758
Scientific name: Cyprinus carpio Linnaeus, 1758
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1.3 Habitat and biology of Cyprinus carpio
The Cyprinus carpio is an adaptable freshwater species. The species is typically
full-scaled and coloured silvery-black or grey, olive-green or yellow-brownish on their
backs, softening to pale yellow or cream on their bellies (Figure 1.1) (Kirpitchnikov,
1967; Balon 1995a; Lintermans, 2007), although many colour and scale variants occur
in both wild and cultivated populations. They are globally distributed and has firmly
established populations on every continent except Antarctica (Lever, 1996). Common
carps are tolerant to low oxygen levels, high levels of turbidity, moderate salinity
(14%), a wide range of temperatures (2 - 40.6 °C) and high levels of toxicants (Koehn
2004). Wild common carp live in the middle and lower streams of rivers, in inundated
areas, and in shallow confined waters, such as lakes, oxbow lakes, and water reservoirs.
Common carp are mainly bottom dwellers but search for food in the middle and upper
layers of the water body. They sucked sediments into their mouths and expelling
indigestible particles through their gill openings (Billard, 1999; Koehn et al., 2000).
Best growth is obtained when water temperature ranges between 23 °C and 30 °C.
Common carps can reach 0.6 to 1.0 kg body weight within one season in the
polycultural fish ponds of subtropical/tropical areas. Growth is much slower in the
temperate zone: here the fish reach the 1 to 2 kg body weight after 2 to 4 rearing
seasons. The maturity period of Asian carp strains is slightly shorter. The spawning of
European carp starts when the water temperature is 17-18 °C. Asian strains start to
spawn when the ion concentration of the water decreases abruptly at the beginning of
the rainy season (Crivelli, 1981). In tropical and subtropical regions carp usually mature
during their first year and may spawn several times within a given year (Sivakumaran et
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al., 2003). Female gonad development is continuous when temperatures are above 16°C
(Crivelli, 1981). Wild common carps are partial spawners (Tekelioglu, 2000).
Domesticated common carps release all their matured eggs within a few hours.
Common carp is capable of laying eggs in the closed fish rearing ponds (Bauer and
Schlott, 2004).
1.4 Food and Feeding of Cyprinus carpio
Common carp are bottom feeders, feed by filtering small particles from the water
or by sieving food items from the bottom sediments, sucking sediments into their
mouths and expelling indigestible particles through their gill openings (Koehn et al.,
2000). During feeding, food is sucked into the mouth along with water and sediments.
At the entrance to the pharynx or throat, gill rakers form a meshed structure that can
sieve out larger items from the ingested water and sediments, which are expelled
through the opercular openings behind the gills. This behaviour can stir up fine
sediments and increase turbidity (Koehn, 2004). Their diet varies, depending on what
foods are available, but they are known to eat micro crustaceans, aquatic insect larvae,
molluscs, swimming and terrestrial insects and seeds and other plant matter (Koehn et
al., 2000). According to Eder and Carlson (1977), they are omnivorous, feeding mostly
on benthic organisms (e.g., chironomid larvae and pupae), detritus, and algae. Juvenile
carp feed mainly on small planktonic animals, smaller crustaceans and insect larvae. As
common carp grow they gradually eat larger crustaceans and aquatic insects, along with
some plant material. Common carp have a high tendency towards the consumption of
animal food, such as water insects, larvae of insects, worms, molluscs, and zooplankton.
Zooplankton consumption is dominant in fish ponds where the stocking density is high.
Additionally, the common carp consumes the stalks, leaves and seeds of aquatic and
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terrestrial plants, decayed aquatic plants, etc (Flajshans and Hulata, 2006). They are
voracious feeders. With the extendible mouth they suck in all the decaying materials
and the micro organisms along with the clay from the bottom of the pond and take in the
feed and expel the clay and other non edible portions. They also eat up all kinds of
micro organisms, worms and small aquatic creatures found at the bottom of the pond.
They have the habit of making holes on the sides and at the bottom of the pond and
thereby affect the stability of the pond or the trees that may be growing on the bank of
the pond (Zambrano and Hinojosa, 1999). Their diet may alter depending on prey
densities (Scheffer, 1998). For example, high density, cyprinid populations like Green
Lake common carp may switch to feeding on zooplankton when abundant rather than
benthos. High predation pressure on algae-grazing zooplankton ultimately leads to high
algal biomass (Scheffer, 1998).
1.5 Subspecies and strains of Cyprinus carpio
Wild common carp are typically torpedo-shaped, full-scaled, and coloured
silvery-black or grey, olivegreen or yellow-brownish on the dorsal surface, softening to
pale yellow or cream on the ventral surface and flanks (Kirpitchnikov, 1981; Balon,
1995; Lintermans, 2007). Variations in scale morphology, colour and body shape,
however, are common in both wild populations and domestic strains. Domestic common
carp are typically rounder and plumper-bodied than wild carp. Feral population of
domestic common carp, however, revert to a wild-type body shape soon after
establishment (Balon, 1995). Traits such as dwarfism, the absence of ventral fins, the
presence of an additional fin, elongated fins and a dolphin-like head have also been
reported in both wild and domestic populations (Kirpitchnikov, 1981; Wang and Li,
2003). Owing to a large geographic range, a long history of culture and artificial
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selection by humans for aquaculture and ornamental
varieties of C. carpio (USGS, 2005) which
Kirpitchnikov (1967) recognized four subspecies of
carpio (Europe), C. c. aralensis
c. viridiviolaceus (South East Asia). But, Balon (2006) suggested that
subspecies could be clearly recognized:
(East Asia). Kirpitchnikov (1999) then questioned t
Most recently, Kottelat (2001) considered the common cultured carp in S
to be a distinct species, C. rubrofuscus
populations in Eurasia is shown in figure 1.5.
Figure 1.4. Ranges of wild common carp populations in Eurasia
1999; Chistiakov and Voronova, 2009).
There are about 30-35 strains of domesticated common carps in Europe.
strains are maintained in China.
have a broken pattern of unusually large scales or
and leather carp respectively. If the common carp h
Cyprinus carpio
Cyprinus carpio
Cyprinus carpio
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selection by humans for aquaculture and ornamental purpose there are a number of
(USGS, 2005) which exhibit much morphological variation
Kirpitchnikov (1967) recognized four subspecies of common carp viz.
C. c. aralensis (Central Asia), C. c. haematopterus (East Asia) and
(South East Asia). But, Balon (2006) suggested that
subspecies could be clearly recognized: C. c. carpio (Europe) and C. c. haematopterus
(East Asia). Kirpitchnikov (1999) then questioned the validity of C. c. viridiviolaceus.
lat (2001) considered the common cultured carp in South East Asia
C. rubrofuscus. The geographical range of wild common carp
shown in figure 1.5.
. Ranges of wild common carp populations in Eurasia (from
1999; Chistiakov and Voronova, 2009).
35 strains of domesticated common carps in Europe.
in China. Sometimes genetic variants are found in the wild th
have a broken pattern of unusually large scales or no scales at all, known as mirror carp
and leather carp respectively. If the common carp has only a single row of scales it is
Cyprinus carpio carpio
Cyprinus carpio haematopterus
Cyprinus carpio viridiviolaceus�
purpose there are a number of
logical variation.
common carp viz. Cyprinus carpio
(East Asia) and C.
(South East Asia). But, Balon (2006) suggested that only two
C. c. haematopterus
C. c. viridiviolaceus.
lat (2001) considered the common cultured carp in South East Asia
range of wild common carp
. Ranges of wild common carp populations in Eurasia (from Kirpitchnikov,
35 strains of domesticated common carps in Europe. Many
Sometimes genetic variants are found in the wild that
no scales at all, known as mirror carp
as only a single row of scales it is
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called a line carp (USGS, 2005). The nishikigoi, or koi as it is commonly known as in
the United States, is also a type of C. carpio, as are the Oujiang color carp and the long-
fin carp. ‘Mirror’ scales are a common feature of domestic common carp strains. These
scales are larger and shinier than ordinary scales, and usually do not covers the entire
body (Kirpitchnikov, 1981). The absence of normal scales has been favoured by
artificial selected in domestic fish to make them easier to de-scale for cooking
(Michaels, 1998).
The colour variations of common carp include golden, red, blue, orange, steel,
green, albino, yellow, lemon-yellow, green, violet and brown which are seen in both
wild and domestic populations (Kirpitchnikov, 1981; Wang and Li, 2003). Red, golden
and orange individuals are found amongst domestic and wild populations in both
Europe and Asia (Kirpitchnikov, 1981; Balon, 1995a). Moreover, the selective breeding
has led to the production of fancy carp, or koi, in Japan which are now available in a
wide range of colours, scale morphologies and body shapes.
In physical shape, common carp are characterized by two types: one with big
stomach and other with slender body. The body is elongated and somewhat compressed
and flat on both sides. The mouth can be extended forward as it opens up. The lips are
thick and smooth. Two pairs of fleshy whiskers (barbels) are present on either side of
the mouth, with the posterior pair being longer than the anterior pair (Koehn et al.,
2000). Dorsal fin base long with 17-22 branched rays and a strong, toothed spine in
front; dorsal fin outline concave anteriorly. Anal fin having 6-7 soft rays and anal fin
spines with sharp spinules. The scales are large and cycloid with 33–40 scales along the
lateral line and scales are absent on the head. The colour of common carp is genetically
determined, but some environmental effects, such as colloid content of water and the
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age of fish influence the shading of inherited colouring. The colour is variable, wild
carp are brownish-green on the back and upper sides, shading to golden yellow
ventrally. The fins are dusky, ventrally with a reddish tinge. Golden carp are bred for
ornamental purposes. Other traits are forked tail (caudal fin); no teeth in the mouth;
three rows of pharyngeal teeth on the lower element of the last gill arch, the outer two
rows of these pharyngeal teeth each having one tooth and the inner row having three
teeth (1,1,3:3,1,1 arrangement, which separates common carp from many other Cyprinid
species). Pharyngeal teeth are a distinguishing characteristic in the Cyprinid family,
both by structure and number, but within the strains of common carp there are no
remarkable differences (Bakos and Gorda, 2001).
Morphological description of strains includes the qualitative characters
determining the external features and also taxonomic classification (FAO, 2005). The
scaliness of common carp as a determining factor consists of four different basic forms:
scaly, mirror (scattered), linear and leather (naked) varieties. These types of scaliness
are determined genetically by four alleles at two loci, designated Ss and Nn, which
display Mendelian inheritance. The scaly carp results from the SS, nn and Ss, nn
combinations. The ancient, primitive populations and the oldest cultured forms are
covered with a regular pattern of scales. The mirror carp results from the homozygote
recessive ss, nn genotype exclusively. The typical mirror pattern is a single unbroken
row of scales on the top of the back, some scales near the tail and at the base of fins.
Preferably there are no scales along the lateral line or scattered across the surface of the
body in the mirror carp. The linear carp is basically similar to the mirror, but the lateral
line is completely covered by a wide line of scales. This is determined by the SS, Nn
and Ss,Nn genotypes. The leather carps result from the ss, Nn genotype and are
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absolutely scaleless. Irregularly, a few scales can be found at the base of fins.
Transitional forms of scaliness similar to linear or leather varieties can sometimes be
observed in mirror carp (ss, nn genotype), but these are called strongly- or slightly-
scaled irregular mirror or scattered carps (Bakos and Gorda, 2001).
1.6 Distribution of Cyprinus carpio
The common carp is perhaps the highly distributed fish all over the world. The
original natural distribution of common carp was restricted to a narrow belt in central
Asia within latitude 35˚-50˚N and longitude 30-135˚E and altitude 300m above sea
level (Jhingran and Pullin, 1998). It is now distributed in Western Europe throughout
Eurasia to China and Southeast Asia and from Siberia to Mediterranean and India. In
the past two centuries, common carp was introduced into Africa and America, which
make it one of the most important aquaculture species worldwide with an annual global
production of 3.4 million metric tons (FAO, 2007). As per FAO (Food and Agriculture
Organisation) database, common carp has been introduced in 110 countries while it is
native to 24 countries. Common carp can tolerate a variety of conditions but are
generally found in lakes and slower flowing rivers with soft bottom sediments (MD
DNR, 2008). They can live in fresh to brackish water and thrive from 20 to 60 degrees
North and South. C. carpio is one of the first fish species to be introduced into other
countries with human aid and now enjoys global distribution (MD DNR, 2008).
Fishbase.org (Froese and Pauly, 2008) has a comprehensive list of the status of common
carp in every country. The status of common carp is shown in three categories: native,
introduced, and not-established (Figure 1.5). Basically "native" means that carp live in
an area independent of human interference and have free-living and self-maintaining
populations, "introduced" refers to wild populations of carp are established but only
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because at one time people brought them there, and
conditions where carp are found in a country but ar
self-maintaining populations.
With the help of radiotracking Koehn and Nicol (199
is a mobile species. Large movements occurred both
individuals moving up to 230 kilometres between Yar
Murray River in Australia in
the year apparently independent of water temperatur
Figure 1.5. Global distribution of common carp (source:
and map designed by Joshua Ro
1.7 Culture of Cyprinus carpio
The Cyprinus carpio
food. They have been reared in ponds in China as ea
(B.C) (Horvath et al., 2002). Buddhist monks were probably responsible fo
distribution of carp from China and Vietnam through
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because at one time people brought them there, and "not established" refers to
conditions where carp are found in a country but are not widespread in free
ations.
With the help of radiotracking Koehn and Nicol (1998) showed that common carp
is a mobile species. Large movements occurred both upstream and downstream, with
individuals moving up to 230 kilometres between Yarrawonga and Barmah on the
Australia in only a few months. These movements occur throughout
the year apparently independent of water temperatures as low as 8°C.
. Global distribution of common carp (source: Rearranged from Fishbase.org
Joshua Robert Leisen).
Cyprinus carpio
Cyprinus carpio has been one of the oldest domesticated species of
food. They have been reared in ponds in China as early as the 5th century
2002). Buddhist monks were probably responsible fo
distribution of carp from China and Vietnam throughout south–east Asia. In Europe, the
"not established" refers to
e not widespread in free-living and
8) showed that common carp
upstream and downstream, with
rawonga and Barmah on the
only a few months. These movements occur throughout
Rearranged from Fishbase.org
has been one of the oldest domesticated species of fish for
rly as the 5th century Before Christ
2002). Buddhist monks were probably responsible for the
east Asia. In Europe, the
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domestication of carp was started by monasteries in the 12th century. Balon (1995a)
argues for an even older domestication of common carp in Europe, suggesting that
common carp were first domesticated by the Romans in the 1st and 2nd centuries
Christian Era (C.E). This argument is based on evidence that the Romans maintained
ponds for freshwater fish, and that common carp were an important food source in
Roman settlements along the River Danube. There is, however, no direct evidence to
support this theory. The common carp was a luxury food in the middle and late Roman
period, and it was consumed during fasting in the middle Ages. The fish were kept in
storage ponds by the Romans, and later in fish ponds constructed by Christian
monasteries. In this European practice the common carp were kept in monoculture.
Balon (1995a) also disputes early domestication of common carp in China, arguing that
the fish stocked in early Chinese ponds could have been other carp species, such as
grass carp, silver carp or the Indian major carps, rather than Cyprinus carpio. While it is
difficult to verify exactly which species were reared in ancient China, there is currently
a wealth of aquaculture carp strains in China that have been derived from indigenous
wild populations and have a long history of cultivation (Kohlmann et al., 2003; Zhou et
al., 2004a; Zhou et al., 2004b). Xingguo red carp, for example, have been cultivated for
approximately 1,300 years (Zhou et al., 2004a). Even if common carp domestication in
China does not date back to the B.C.E. period, it has been in practice in this region for
over 1,000 years. Today common carp are a globally important species. The common
carp was introduced in several countries of East, Middle and West, as this fish was
found to be the easiest to culture intensively. Although in America and Canada its
culture did not flourish, its cultivation became very popular and widespread in Europe,
Asia and Israel. Now, India is also a leading producer of common carp. Being fecund
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and robust, they are ideal for aquaculture and as such, are farmed extensively
throughout Eurasia, and to a lesser extent in North and South America (Zambrano et al.,
2001) and Africa (Costa-Pierce et al., 1993). In Asia they are typically grown in
polyculture ponds with 3-5 other fish species, each exploiting a different ecological
niche in the pond (Koehn et al., 2000). The harvesting of common carp for food, both
from the wild and from aquaculture, has been growing steadily since the late 1970s
Common carp are subsequently an important source of protein and provide income for
many people. When culturing began, wild forms of common carp from ancient
populations dominated. Some of them exist up to the present day as elongated scaly
forms of wild carps enriching the local fish fauna, but most cultured common carp now
look different from their ancestors.
The culture practices of common carp is vary from place to place and country to
country; these may be classified as pond culture, cage culture, culture in paddy fields,
culture in sewage-fed water, culture in streams, culture in closed recirculating water
system and culture combined with duck raising. Cultivation of common carp is
practised as monoculture as well as poly-culture. The common carp is preferred in the
culture system because of some attributes such as i) it is a very hardy fish; it can tolerate
wide pH range, salinity range and temperature range; and high turbidity, ii) fish is
omnivorous; iii) fish can be easily flattened on cereals and leguminous seeds, iv) fish
feeds well on a variety of artificial foods, v) fish is easily induced to spawn in captivity,
vi) fish does well as a constituent of poly-culture vii) fish responds well to selective
breeding and hybridization, making improvements feasible in the race viii)fish is found
to be more economical to raise. Another impetus to the culture of common carp is the
suitability in poly-culture practices. The common carp is an omnivorous feeder and
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successfully used in mixed rearing. The yield of such polyculture is often very high as
compared to that of monoculture in a pond. In polyculture, common carp is reared with
tench (Tinca tinca) in Yugoslavia; roach (Rutilus rutilus) in France, mullet and tilapia in
Israel, gold fish and bream (Abramis brama) in Russia (Srivastava, 1995).
1.8 Breeding of Cyprinus carpio
Common carp breeds once annually in temperate waters but several times in a
year in tropical waters. This disadvantage of temperate waters can be made over with
application of the induced breeding technique. In tropical waters, the availability of
spawn is assured throughout the year. It takes only three months for both sexes to be
ready for the next spawning after the last one (Vilizzi and Walker, 1999). In India, as
many as five spawning in a year have been recorded in the case of common carp.
Widespread adoption of common carp culture in tropical and semi-tropical waters is
attributed to this single advantage; common carp not only competes well with
indigenous species native of the place on this point but even commands preference over
the latter. In the tropics, common carp attains sexual maturity in the first year. Sexes are
distinguished with great difficulty. Whereas older sexes are relatively easily identified
due to the presence of tubercles on the side of the head and on the paired fins of males,
young sexes can be recognized only after stripping of gonadal products. Fecundity
varies according to size. A typical adult common carp can lay 300,000 eggs in a single
spawning. The number of eggs varies from 36,000 to 2,000,000 in a single spawning
season by each female. Although carp typically spawn in the spring, in response to
rising water temperatures and rain fall, carp can spawn multiple times in a season. In
natural conditions spawning are stimulated in two ways: i) use of water slightly warmer
than water of pond where breeders were stocked, and ii) real plants (Hydrilla, Naja or
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similar weeds) or artificial plants and other egg collecting devices (Kakaban of
Indonesia) (Srivastava, 1995). In commercial operations, spawning is often stimulated
using a process called hypophysation. In such condition, common carp generally breeds
within 6 to 10 hrs after being released in the breeding pool and by morning, the egg
collectors could be seen with millions of eggs. Eggs are adhesive and deposited onto
plant material such as submerged plants, tree roots, roots of undercut banks, leaf litter,
and/or logs in a mass or singularly (Wang, 1986) in spring to early summer. Eggs are
generally round to oval and either clear or tinted yellow. Eggs are abandoned by the
female and hatch in 3 to 5 days after being laid. In artificial breeding the eggs are then
transferred to the hatching hapa. Hatching is best achieved in a cloth hapa. Fertilized
eggs look a dirty yellow in colour and may be easily distinguished from the dead or
unfertilized eggs which are opaque and white. Hatching occurs in 46 to 48 hours at 28
to 310C. If the water temperature is less than this, the incubation period prolonged in
temperate climate at 200C hatching takes a much longer period extending even up to
144 hours. The just hatched larvae attach to walls or plants by means of their cement
glands. When the yolk sac is absorbed they become free swimming and begin to feed.
Paucity of food supply may lead to heavy mortality. Transfer to nursery ponds may be
done within the first three weeks of spawning. Females may spawn several times in one
season. Juvenile carp live in shallow floodplain habitats and are more abundant where
the density of adult carp is low (Srivastava, 1995). Growth rates of common carp vary
greatly between different regions, depending on temperature, food availability and
population density. Common carp grow rapidly and reach 10 to 13 centimeters in length
within the first year of life (Steiner, 2000). Common carp have been reported to live up
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to 20 years and reach a maximum weight of 60 pounds (27.216Kg), though most fall
between 1(0.4536Kg) and 10 pounds (4.536Kg) (Wang, 1986).
The embryonic development of common carp takes about 3 days at 20-23 °C.
Under natural conditions, hatched fry stick to the substrata. About three days after
hatching the posterior part of the swim bladder develops, the larvae swim horizontally,
and start to consume external food with a maximum size of 150-180 µm (mainly
rotifers). Gonad weight in mature females is between 15 and 30 % of total body mass.
Males have relatively large testes (5-10% of BW). Egg size averages 1000 eggs /gram
(Balon, 1995a). Common carps reproduce in spring time, and spawn only once in
temperate climates. Under laboratory conditions, (see earlier) carp females can be
stripped every 8 weeks. Males can be stripped every 10 days. Ovulation is induced with
carp pituitary, either as crude preparation, or as extract, in two injections. Stripped eggs
have limited storage time (2-4 hours at room temperature). Milt can be diluted in
extenders, and stored at 0-4ºC for several days. Eggs are degummed prior to fertilization
and incubated in conical upflow jars. Hatching is temperature dependent and takes place
after 3-5 days of incubation (range for 18 - 25ºC). Common carp may spawn throughout
the year in tropical areas of India, with peaks in January-March and July-August
(Linhart et al., 1995). Breeding is carried out in hapas, cement tanks or small ponds.
Submerged aquatic plants are used as substrata for egg laying. When the fry are 4 to 5
days old, they are stocked into nursery ponds. Common carp are stocked with Chinese
carps, and/or Indian major carps, tilapia, mullet, etc., in polycultural systems. This
constitutes a natural food and supplementary feed-based production method, in which
fish that have different feeding habits and occupy different trophic niches are stocked
into the same ponds. The frequent application of manure or fertilizers and the proper
�
species ratio, make the maintenance of productive p
organisms, and the maximal utilization of the produ
(Jhingran and Pullin, 1985;
1.9 Global production of
Globally, common carp is a major culture species, a
cyprinid production. In 2007, world production of c
million ton from approximately 80 countries and re
global freshwater aquaculture increased by an avera
between 1980 and 2007 (Jeney and Jian, 2009). The g
Cyprinus carpio from 1950 to 2010
Figure 1.6. Graph showing increased global aquaculture produc
from 1950 to 2010. (Source: FAO Fishery Statistic)
India is the sixth largest producer of fish in the
second in world aquaculture produc
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species ratio, make the maintenance of productive populations of natural food
organisms, and the maximal utilization of the productivity of pond ecosystem possible
; Kestemont, 1995; Parihar, 1999).
Global production of Cyprinus carpio
Globally, common carp is a major culture species, accounting for 15.2% of all
cyprinid production. In 2007, world production of cultured common carp reached 2.9
million ton from approximately 80 countries and regions, which was 9.9% of total
global freshwater aquaculture increased by an average global rate of 7.9% per year
between 1980 and 2007 (Jeney and Jian, 2009). The global aquaculture production of
from 1950 to 2010 is shown in Figure 1.4.
. Graph showing increased global aquaculture production of Cyprinus carpio
from 1950 to 2010. (Source: FAO Fishery Statistic)
India is the sixth largest producer of fish in the world (6.41 million tonnes) and
second in world aquaculture production (2.22 million tonnes) (Basavaraja,
opulations of natural food
ctivity of pond ecosystem possible
ccounting for 15.2% of all
ultured common carp reached 2.9
gions, which was 9.9% of total
ge global rate of 7.9% per year
lobal aquaculture production of
Cyprinus carpio
world (6.41 million tonnes) and
Basavaraja, 2007). Carps
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are the most widely cultured freshwater fish in India. Mixed species culture is most
common where the three species of Indian major carps (IMC), i.e. catla (Catla catla),
rohu (Labeo rohita) and mrigal (Cirrhinus mrigala) are cultured with three exotic carp
species, namely, silver carp (Hypophthalmichthys molitrix), grass carp
(Ctenopharyngodon idella) and common carp (Cyprinus carpio). However, the number
of species and their combination vary depending on seed availability, consumer
acceptance and ability to grow well in different environments. The common carp is
perhaps the world’s most extensively cultured species. The Bangkok Strain of common
carp is one of the most widely farmed fish globally. In India, it is one of the four fish
species commonly farmed either singly or in combination with the IMCs and also with
the Chinese carps, grass carp and silver carp. Cyprinus carpio is an omnivorous fish,
capable of withstanding fluctuation in the water levels and other adverse environmental
factors. It grows almost at par with the fastest growing IMC, the catla. However,
sometimes, due to its prolific breeding habit, it offsets the stocking density of the
culture pond, resulting in a production of undersized fish of very low market value
(Basavaraja, 2007). Detailed studies on the cultivable aspects of common carp have
been carried out at the Pond Culture Division of Central Inland Fisheries Research
Institute (CIFRI), Barrackpore, India. The common carp breeds naturally in confined
waters. Spawning occurs in shallow marginal weed-infested areas. It spawns throughout
the year in a tropical country like India, with two peak breeding seasons, one lasting
from mid-January to March and the other during July and August. However, diverse
breeding techniques of this species have been described (Hora and Pillay, 1962;
Alikunhi, 1957; Alikunhi, 1966).
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1.10 Genetic variability of Cyprinus carpio
Common carp has been cultured for several centuries, initially in temperate European
and Asian countries, and has been significantly altered by deliberate and accidental
genetic changes over this long period of culture (Basavaraju et al., 2004). In some
tropical regions, the common carp adapt to local conditions through unconscious
selection, genetic drift and inbreeding, commonly resulting in a deterioration of culture
performance. In China, variants of C. carpio have been artificially selected for
ornamental purposes. Release of exotic fish into the wild water bodies of a country can
have genetic impacts at three levels: on the individuals released, on specific native
individuals or on closely related indigenous species and the effects can be either direct
or indirect. Direct impacts include those that operate on a species by initiating changes
in gene flow, through hybridization and introgression. Indirect effects are primarily
those caused by inadequate number of spawners, either through release of a small
number of individuals, or in the indigenous species through ecological processes such as
competition, predation, new diseases or parasites. Such genetic effects may lead to a
loss of indigenous fish populations and their genetic diversity. Fishes have a greater
potential for successful hybridization without sterility than either mammals or birds, and
this may lead to complex introgression when domesticated fishes meet the wild stocks.
Exotics may thus interbreed with either native congeners or with other aliens. Examples
of genetic deterioration due to alien fish species introductions and transfers within
aquaculture activities are very numerous (Arthington, 1991). The environmental impact
of such deterioration is evident as aquaculture facilities are, except in very rare
situations, connected with the hydrographic system (rivers, lakes) and both accidental
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stocking and interactions with wild populations may occur quite often. The most
frequent cases concern introgressive hybridization and loss of genetic variability.
Hybridisation can also lead to changes in chromosome number (ploidy), creating
lineages that have one or two complete sets of chromosomes from two separate species
(allopolyploid lineages). These lineages can be capable of, or limited to, asexual
reproduction (parthenogenesis). They can subsequently have greatly elevated levels of
reproductive output, as all individuals are capable of producing offspring (Billington
and Hebert, 1991). In Africa and Latin America, there has been a widespread breeding
of different genetic strains, particularly of the tilapiine cichlids, which has already
resulted in a considerable mixing of the gene pool. Indirect effects arise from the impact
of reductions in population size on genetic diversity, either through release of too few
individuals (founder effect), high mortality due to adaptation to new environments
(population bottleneck) or ecological effects on native fish through such forces as
competition, predation or transfer of diseases or parasites from introduced fish. The
common carp genetic studies had been performed in the last few years, which focused
on development of genetic markers (Zhou et al., 2004a; Wang et al., 2007; Zhang et al.,
2008; Kongchum et al., 2010) for breeding and genetic evaluation, construction of
genetic maps (Sun and Liang, 2004; Cheng et al., 2010) and physical map (Xu et al.,
2011a), collection of a large set of ESTs (Christoffels et al., 2006) and microRNA (Yan
et al., 2009), construction of bacterial artificial chromosome (BAC) library (Li et al.,
2011) and collection BAC-end sequences (BES) (Xu et al., 2011b), transcriptome study
with cDNA microarrays (Moens et al., 2007), characterization of functional genes (Wan
et al., 2011) and quantitative trait loci (QTL) analysis (Zhang et al., 2011).
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1.11 Phylogeography
Phylogeography is concerned with the principles and processes governing the
geographical distributions of genealogical lineages, especially those at the intraspecific
level (Avise, 1998, 2000). Phylogeographic study is undergoing a major expansion as
the range of convenient genetic markers available to study geographic variation
increases. Ultimately, the aim of phylogeography might be defined as a means to
understand microevolution and speciation in its geographic or spatiotemporal context.
Understanding the geographical context of the observed pattern is essential in the
development of evolutionary models of real organisms (Kidd and Michael, 2006).
Detecting coincidence or concordance of geographic variation in genotypes, or their
genealogies, and the environment is therefore at the heart of phylogeographic inference.
Geographical concordance between genealogies may be across sequence characters
within a gene, between significant genealogical partitions across multiple genes within a
species, or in the geography of gene-tree partitions across multiple co-distributed
species. The latter has been called comparative phylogeography and may provide a
‘bridge’ between the historically separate disciplines of phylogeography and historical
biogeography (Bermingham & Moritz, 1998). A wider definition of phylogeography
includes genetically controlled traits, such as morphology or behaviour, for which
comparable concordance patterns can be studied (Avise, 1998). Phylogeographers must
manipulate a wide range of data and information types including ‘raw’ character
matrices and DNA sequences, derived trees and network graphic representations,
coalescent hypotheses as well as external contextual data describing environmental
variation and landscape structure. Phylogeography therefore utilizes a heterogeneous set
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of quantitative and qualitative data obtained from a wide variety of sources with
differing data structures, e.g. trees, networks, spatial grids or vector points, lines or
polygons. Phylogeography integrate both phylogeny and geography within a
quantitative analytical framework that encompasses the diverse aspects of
phylogeographic concordance. Without such a framework, phylogeography will remain
essentially a narrative biogeographic approach (Humphries, 2000). In the phylogenetic
or population genetic approach, graphical phylogenetic trees, networks or clades are
calculated from the observed variation data. These graphical representations of
evolutionary relationships are subsequently compared to external information that could
be another trait of the same organism, a trait or distribution of a different organism, or
an environmental variable, to identify congruent spatial and phylogenetic pattern
facilitating the inference of, usually qualitative, historical scenarios (Taberlet et al.,
1998; Hewitt, 1999). Population genetics in relation to biogeography have been studied
by several authors in different ichthyo-faunas. For example, phylogeographic studies of
the fishes of the south-eastern United States was done by Bermingham and Avise
(1986), Nearctic North America by Bernatchez and Wilson (1998), Central America by
Bermingham and Martin (1998), and Australia by Hurwood and Hughes (1998).
1.12 Biochemical composition
Fish is one of the important food sources as it includes essential fatty acids, amino
acids and some of the principal vitamins and minerals in sufficient amounts for healthy
living (Borgstrom, 1961). It has been widely accepted as a good source of protein
(Andrew, 2001) and it is rich in essential amino acids (lysine, methionine, cystine,
threonine, and tryptophan). Amino acids are the building blocks of proteins and help to
maintain health and vitality. There are 20 amino acids that can be found in the human
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body, 18 of which are important in human nutrition. Eight amino acids cannot be
synthesised de novo by humans and other mammals and hence must be supplied in the
diet; therefore they are called essential amino acids. The nutritive quality of any food
protein is determined by the i) the content of essential and nonessential amino acids; ii)
the mutual proportions of specific essential amino acids, which preferably should be
similar to that found in the proteins of the body; iii) the energy supplied, which is
essential for protein synthesis in the body; iv) the digestibility of the protein (Boisen et
al., 2000). Fish meat contains significantly low lipids and higher water than beef or
chicken and is favored over other white or red meats (Neil, 1996). In human nutrition,
fatty acids such as linoleic and linolenic acids are important for preventing skin diseases
and are considered essential as they cannot be synthesized by the organism. However,
fish oils contain other "essential" polyunsaturated fatty acids which act in the same way
as linoleic and arachidonic acids (Elvevoll and James, 2002). Fish lipids are well known
to be rich in long-chain n-3 polyunsaturated fatty acids (n-3 PUFA), especially
eicosapentaenoic acid and docosahexaenoic acid. Long chain, n-3 PUFA cannot be
synthesized by humans and must be obtained from the diet (Alasalvar et al., 2002).
Minerals are essential nutrients, they are components of many enzymes and metabolism,
and contribute also to the growth of the body (Glover and Hogstrand, 2002). These are
obtained by human from different food sources. Fishes are important source of
minerals. Minerals are chemical constituents used by the body in many ways. Although
they yield no energy, they have important roles to play in many activities in the body
(Malhotra, 1998). Every form of living matter requires these inorganic elements or
minerals for their normal life processes (Hays and Swenson, 1985). The importance of
mineral elements in human, animal and plant nutrition has been well recognized.
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Deficiencies or disturbances in the nutrition of an animal cause a variety of diseases and
can arise in several ways (Soetan et al., 2010). Minerals play a critical role in various
body functions and are necessary to sustain life and maintain optimal health for humans
and animals. Calcium and phosphorus as macro-nutrient are the most important
elements in exoskeleton, bone, scales, and teeth formation and responsible for
maintaining the acid-base equilibrium (Watanabe et al., 1997). In addition calcium is
required for blood clotting process while phosphorous is a component of
deoxyribonucleic acid (DNA), ribonucleic acids (RNA), nucleotide and act as a co-
factor for different enzymes (Davis and Gatlin, 1996). For example, manganese is
considered to be an activator for different enzymes such as leucine-aminopeptidase and
zinc activates the alkaline phosphatase enzyme. Some trace elements serve as
metalloproteins (e.g. iron in haemoglobin, copper in haemocyanin) or metalloenzymes
(e.g. zinc serves as a metalloenzyme for carbonic anhydrase, carboxypeptidases,
glutamic dehydrogenase and a variety of other enzymes (Clark et al., 1987).
Biochemical composition of flesh is a good indicator for the fish quality, the
physiological condition of fish and habitat of fish (Shamsan and Ansari, 2010;
Ravichandran et al., 2011). Fish of various species do not provide the same nutrient
profile (Takama et al., 1999) and the nutritive value of a fish varies with season
(Varljen et al., 2003).
1.13 Impact of Exotic Fish
Non-indigenous species may affect indigenous species by competing for
resources, preying on native fauna, transferring pathogens, or significantly altering
habitat (Pimentel et al., 2000). In India, tilapia (Oreochromis mossambicus) was
introduced in 1952 in certain as ponds and reservoirs, but the species spread all across
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the country within a few years due to its prolific breeding and adaptability to wide range
of environmental condition. A number of other exotic fish species such as Aristichthys
nobilis, Clarias gariepinus, Pangasianodon hypophthalamus, Oreochromis niloticus,
Pygocentrus natterei, Piaractus brachypomus etc have been introduced illegally in
India (Goswami, 2000). Tilapia is an omnivorous grazer that feeds on phytoplankton,
periphyton, aquatic plants, small invertebrates, benthic fauna which causes loss of
biodiversity in aquatic ecosystem. Overpopulation of the species affected the fisheries
of several reservoirs in Tamil Nadu, Kerala, Karnataka, Rajasthan and West Bengal and
also posed threat to species like mahseers (Tor tor and T. putitora), which are on the
verge of extinction (Thakur, 1996). Exotic fish Grass carp, Ctenopharyngodon idella
has been found to consume plant material, and uprooting macrophytes which cause
erosion of bank. During flood this fish cause huge loss to the paddy field. In pond they
mostly consume tender species and tougher aquatic plants remain untouched. This
causes modification of aquatic plant communities which could significantly affect
trophic structure of aquatic ecosystem (Choudhury et al., 2012). Due to sharing of food
and aggressive behaviour, the exotic fishes can alter trophic relationships in aquatic
communities in different ways such as increase the amount of prey available to native
predators and can reduce the amount of forage available to native species (Moyle,
1986). Diseases caused by bacteria, viruses, and parasites are often conveyed along with
exotic species and may pose threat to a native community by transfer of parasites from
exotic to native fishes. Rainbow trout, Oncorhynchus mykiss from western North
America have carried furunculosis to Europe. North American fathead minnow
Pimephales promelas has been proved to introduce Yersinia ruckeri, which is the
causative agent of red mouth disease to parts of northern Europe. The cause of outbreak
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of the parasitic fluke in Norway was due to introductions from farmed salmonids to
wild population (Langdon, 1989; Whittingham and Chong, 2007).
Fishes have great potential for successful hybridization without sterility, and may
produce long-lasting hybrids in the wild. Indigenous species may interbreed with
introduced exotics. Hybridization between exotic and native fishes results loss or
reduced genetic integrity (Hickley and Chare, 2004; Gunnell, 2008). The impacts can be
significant and include loss of pure forms, reduced mating efficiency, less fit stocks
through the loss of adapted gene complexes, disruption of migration (spawning and
feeding) patterns, altered behaviour, changes in life-cycle timing, lower reproductive
output and other effects. Welcomme (1988) found that the translocation of hatchery
reared brown trout Salmo trutta is genetically inferior to wild-bred stock.
Another important report on the impact of introduction of exotic fish is the
elimination of local species. The larvivorous fish Gambusia has been called the “fish
destroyer”, and is said to replace native species aggressively (Singh and Lakra, 2011).
High fecundity power of some exotic fishes causes disappearance of some local species
(Goswami, 2006). In Loktak Lake of Manipur, Cyprinus carpio has now replacing the
endemic fish species particularly Osteobrama belangeri (Singh et al., 2010a). Koehn
(2004) reported that the invasion of Cyprinus carpio in Australia has already causing
serious implications to the native fish communities. Some exotic fishes cause
degradation of aquatic habitat. The introductions of the goldfish and common carp have
affected the ecosystem, by greatly increasing turbidity (Crivelli, 1995; Choudhury et al.,
2012). Habitat degradation and consumption of large amount of macro invertebrates by
common carp affects natural balance of aquatic system (Wilcox and Hornbach, 1991).
The increase in turbidity due to the presence of common carp reduces the light
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availability for aquatic plants, which subsequently reduces survival rate of macrophytes
and create an unfavourable ecological condition in pond (Meijer et al., 1990).
1.14 Invasiveness of common carp
An invasive species can be defined as any species that has been translocated from
its indigenous environment to a new environment and successfully established a self-
sustaining population. Common carp is regarded as invasive species as it is
opportunistic omnivores and adjusted with varying dietary preferences according to
availability of the food (Parks, 2006). It is currently considered to be one of the world’s
most ecologically harmful invasive species (Lowe et al., 2004). Its impacts arise mainly
from the ability to alter aquatic habitats through high levels of excretion and by
disturbing the bottom sediments of water bodies; often resulting in increased turbidity,
degraded water quality and reduced macrophyte and benthic invertebrate densities
(Zambrano and Hinojosa, 1999; Parkos et al., 2003; Matsuzaki et al., 2007). In another
study it was found that introduction of exotic fish could affect the species diversity of
native fish species and could disrupt the food web function of the ecosystem (Jackson,
2002; Vander Zanden et al., 1999). The habitat changes caused by common carp (e.g.,
increased turbidity and loss of macrophytes) may influence small native fish and other
benthic fauna (Llewellyn, 1974). Common carp are currently considered as the worst
freshwater pest fish in both Australia and New Zealand (Chadderton et al. 2003, Koehn,
2004). In several countries it is considered as a problem because of their impacts on
water quality, soft-leaved aquatic plants and native fish populations. But yet the global
aquaculture production of Cyprinus carpio has been increasing in last few decades
(Figure 1.4).
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Table 1.1. Attributes of common cap as invasive species (derived from Koehn, 2004)
Attributes Details
Invasion history, widespread
distribution and abundance
Introduced and established throughout
Europe, Asia, Africa, North, south and central
America, Australia, New Zealand, Papua
New Guinea and some islands of Oceania.
Wide environmental tolerances Temperature tolerance ranges from 2 to
40.60C, salinity tolerances up to 14%, pH
from 5.0 to 10.5, and dissolved oxygen levels
as low as 0.4mg/L.
Early sexual maturity Males at 1 year, females at 2 years
Short generation time 2-4 years
Rapid growth Hatching of eggs is rapid (2 days at 250C)
and newly hatched carp grow very rapidly
High reproductive capacity High fecund broadcast spawners with egg
counts as high as 2 million per female
Broad diet Omnivore/detritivore
Gregariousness A schooling species
Possessing natural mechanism of
dispersal
A mobile species with fish moving between
schools. Dispersal can also occur with
downstream drift of larvae.
Commensal with human activity Bred as an ornamental (koi) and aquaculture
species, used as bait and some anglers.
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1.15 Introduction of Cyprinus carpio in India
Immediately after independence, the Govt. of India had decided to introduce
some exotic species of fish for various purposes such as to meet the demands of the
fish, combating malaria and other vector borne diseases and for ornamental purposes
etc. For this several exotic species have been introduced into India with proper
government approval and for specific intentions. However several other species of
exotic fishes were introduced without any approval or any studies which may be termed
as unintentional. The State is vulnerable to exotic invasion from neibouring country
Bangladesh and several exotic fish species have already invaded from it (Goswami,
2000). In India the common carp was introduced for composite fish farming in India to
increase fish production in ponds, tanks, lakes and reservoir (Srivastava, 1995).
In India, there are three varieties of common carps: viz i) common carps with
small scales regularly covered all over the body called scale carp Cyprinus carpio
communis, (ii) those with shining big scales irregularly covered all over the body called
mirror carp Cyprinus carpio specularis and (iii) those with only few scales on the body
called leather carp Cyprinus carpio. nudus. However, the scale and mirror carps have
become popular in India due to its ability to survive in hot climate. The colour varies
from gray to orange. In India, the mirror carp was introduced for the first time 1939
from Ceylon into Nilgiris. Later on they were introduced to Bangalore and in 1947.
(Yadev, 2006). The Scale carp was brought from Bangkok in 1957 and transplanted to
Cuttack. This Bangkok strain of common carp has been introduced in most of the
reservoirs and lakes of plains where it has been established (Shetty et al., 1989). The
Prussian strain of the common carp was introduced in Nilgiris (Tamil Nadu) in 1939
(Chacko, 1945) and this stock now comprises a mixture of scale carp (C. carpio
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communis), mirror carp (C. carpio specularis) and leather carp (C. carpio nudus). All
these varieties are mostly confined to the cold upland waters and do not generally breed
in the plains (Alikunhi, 1957). The Chinese stock of common carp which breeds freely
in the plains was introduced in 1957 in Cuttack, wherefrom its seed has been distributed
throughout India and its culture popularized (Alikunhi, 1966). Now, Common carp is
widely distributed throughout India have become the most abundant large freshwater
fish in India. Common carp become naturalised in India and has been increasing their
presence in the wild water bodies in India (Singh et al., 2010a).
Increased occurrence of common carp in the Ganga River was recorded and found
that common carp has established in the Ganga River as a pest through naturally
breeding populations which is now becoming the source for invaded to other places
(Singh et al., 2010b). Impacts of exotic fish in the Ganga River have been found to be
mild at present but it may cause habitat alteration, trophic structure alteration, and
hybridization in due course of time (De Silva et al., 2006; Lakra et al., 2008). In
Manipur, Cyprinus carpio has escaped into the Loktak Lake and is now replacing the
important local and endemic fish species particularly Osteobrama belangeri. The
catches of common carp fish production of Gobind Sagar reservoir in the state of
Himachal Pradesh have increased by 30% in the reservoir for the last eight years.
Progressive increase in the catch of common carp was recorded from two tonnes during
1992-93; the catches have increase to 24 tonnes during the year 2009-10
(http://hpfisheries.nic.in). Due to introduction of common carp in the lakes of Kumaon,
the catches of schizothoracids was found to drastically decline (Singh and Lakra, 2006)
and the production of common carp increased since 1985 (Shyam Sunder, 1998).
Besides common carp, a few other alien fish species have established their populations
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in the natural environment of India through natural reproduction. Out of over 30 exotic
food fish species, only carps, tilapia, hybrid catfish and white shrimp have been
commercially used for aquaculture. Grass carps and silver carps introduced into the
lakes and reservoirs for their characteristic feature of controlling excessive vegetation
and plankton bloom respectively (Welcomme and Vidthayanon, 2000). The exotic
fishes were meant mainly for aquaculture, which in due course moved into open waters
inadvertently or because of unawareness which may cause serious ecological problems
(King and Hunt, 1967).
1.16 Occurrences of Cyprinus carpio in Assam
In Assam, several exotic fish species viz. Cyprinus carpio, Ctenopharyngodon
idella, Hypophthalmichthys molitrix, Aristichthys nobilis etc are now available in all
rivers, tributaries and wetlands. However the common carp is found more abundantly
all over Assam. The fish catch reports shows that their numbers have been increasing in
all rivers and wetlands. The above mentioned four exotic species have now shared about
30 to 50% in few markets of Lower Assam. In North East India, the Brahmaputra,
Barak, Teesta, Chindwin and Kola dyne systems with large number of their tributaries,
connected wetlands, numerous hill streams and other streams and rivulets furnish a wide
variety of fish species inhabiting different ecological niches (Nath and Dey, 2000). The
common carp is being farmed in Assam along with Indian Major Carp (Choudhury and
Goswami, 2012). The C. carpio communis is the widely available strain of common
carp in India including Assam. The exotic fish species Cyprinus carpio communis is
now available in all rivers, tributaries and wetlands in Assam. The fish catch reports
shows that their numbers have been increasing in all rivers and wetlands. Various
studies indicate that common carp have great potential to further expand their range in
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India. Considering this, the present study was encompasses a preliminary survey of the
occurrences of exotic Cyprinus carpio communis in two major wetlands (beel) of
Assam.
Assam is blessed with abundant productive and diversified fresh water resources
to harbour various fish species and water birds. The Brahmaputra Valley of Assam
endowed with large number of fresh water bodies, locally called beels. The role of beel
or wetlands in conserving fish diversity has been widely acknowledged as these
ecosystems are used by fishes as a refuge for breeding, feeding and nesting purposes at
one or the other stage of their life cycle (Wetzel, 2001). According to the Directory of
Asian Wetlands (Scott, 1989), India has totally 27,403 wetlands, of which 23,444 are
inland wetlands and 3,959 are coastal wetlands. Wetlands occupy 18.4% of the
country’s area of which 70% are under paddy cultivation. The Wildlife Institute of
India’s survey reveals that they are disappearing at a rate of 2% to 3% every year
(NWCP, 2009). In Assam, beels cover an area of 101232 ha (Jhingran and Pathak,
1987). Beels are considered as one of the most renowned reservoirs of different kind of
fish species and contain a wide variety of peculiar animals and plants of their own.
Wetlands are a land-water linkage of great importance. In a natural system, water
reaches a wetland through rainfall, surface flows or groundwater discharge and leaves
by way of recharge to a groundwater aquifer, discharge to a watercourse, or
evapotranspiration. Wetlands vary in size and depth seasonally, annually, or over longer
time periods with changes in climate. Besides these, wetlands provide quality
environment to the region and accelerating the rural economy. In last two decades, the
indigenous fish populations in the wetlands of Assam have been affected by several
exotic fish species through niche overlapping and habitat degradation (Choudhury et al.,
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2012). The rapid growth of such exotic fish species may affect the indigenous fish
population through competition for food, shelter and breeding sites. The exotic fishes
have high fecundity power and easily adaptable to the environment of Assam. The
decreasing catch rate of several indigenous fish species in natural water bodies may be
due to rapid multiplication of exotic species (Choudhury et al., 2013). There has been
an increasing demand for exotic fish species in India due to high return. The exotic were
brought into the country with the objectives of broadening the aquaculture and
increasing the yield through better utilisation of trophic niches. Now these exotic fishes
have established in the natural water bodies of India including rivers and beels of
Assam through accidental escaping from captivity, flood or during transportation
(Choudhury et al., 2013).
1.17 Invasion of Cyprinus carpio in wetlands of Assam
Considering the approach of the present study, an attempt has been made to have
some information of invasion of Cyprinus carpio and other exotic fish, a preliminary
study was conducted to know the extent of invasion of exotic fish in two wetlands viz.,
Kapla beel and Urpod beel, two open types of wetlands connected with the Brahmaputra
river system. This was examined in two methods. Firstly, the total commercially caught
fishes in Kg was recorded and percentage of each group including exotic fish was
calculated thereof. The percentage of catch of common carp was recorded separately
along with the total catch. Secondly, calculation of Abundance Index of four exotic
fishes (Density of fish populations at each study site) in Urpod beel and common carp in
Kapla beel was done from total catch. In order to collect data on fish catch, field
investigation was conducted from January to December during 2011 at Urpod beel. The
fish production data of Kapla beel was studied from 2008-09 to 2011-12. All data was
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collected on weekly basis and then compiled as monthly basis. Data collections were
done from all important landing centres and market areas of the beel during 6:00AM to
5:00 PM. Fish species in study site were identified by using the keys given by Jhingran
(1975) and Fisher and Bianchi (1984). The abundance index of exotic fish was
calculated by using the following formula (Singh et al., 2010a):
AI (%) = n (k) x100/N
Where, AI = abundance index, n (k) = number of exotic fish caught at each study site,
N = number of all the fish species caught at that site.
1.17.i Invasion of Cyprinus carpio in Kapla beel
The Kapla beels/ wetland is the located at Sarukshetri mouza of Barpeta district of
Assam. It extends between latitude of 26018'12" to 26
025'7" N and between longitudes
of 91008'42" to 91
014'50" E. (Figure 1.7 and 1.9 A, B, C, D). The total area of the Kapla
Beel is about 642 Bigha (91 hectors). The whole area comprises three beels namely
Saru-Kapla, Salmara and Borkona which together constitute a greater Kapla Complex.
The Kapla beel is a beautiful perennial beel of Assam which harbours varieties of
piscean and avian fauna. The water level of the beel changes variably according to
season. It reaches an average height of 13-14 ft during mid rain seasons usually (July to
September), while water level falls to 7-9 ft during the dry season (October –June). This
beel holds a key position in the socio-economic life of surrounding human communities.
The beel act as the perspective spawning ground a variety of fish group including
Indian Major Carps. Kapla Beel harbours about 70 different species of fishes belonging
to 6 major orders like – Cypriniformes, Siluriformes, Channiformes, Perciformes,
Clupeiformes, Mastacembeliformes. Among these, the Indian Major Carps and exotic
carps Cyprinus carpio and Hypopthalmichthys molitrix are the dominant species.
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Figure 1.7. Location map of Kapla beel (www.google
Figure 1.8. Location map of Urpod beel of Assam
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Figure 1.7. Location map of Kapla beel (www.google map.com)
. Location map of Urpod beel of Assam (www.google map.com
Figure 1.7. Location map of Kapla beel (www.google map.com)
www.google map.com)
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Figure 1.9 . Photographs showing parts
beel (E, F) of Assam. The
and Cyprinus carpio communis
abundance has been increasing in the beels in recen
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showing parts of Kapla beel/wetland (A, B, C, D) and Urpod
e beels are the home many indigenous fish species
communis is a commonly available exotic fish species and the
abundance has been increasing in the beels in recent years.
/wetland (A, B, C, D) and Urpod
home many indigenous fish species in Assam
is a commonly available exotic fish species and their
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1.17.ii Fish catch data of Kapla beel
The Kapla beel is a natural habitat and breeding ground for many fish species
including Indian major carps. The beel harbour a large number of other fish groups such
as air breathing fish, minor carps, cat fishes and ornamental fishes. In the present studies
the various fish species found in Kapla beel have been recorded by dividing them into
seven groups namely, Indian Major Carps, Murrels, Catfish, Feather back, Common
carp, Other Exotic fish and Misc. The fish catch data that were collected from the beel
are presented in the Table 1.2. The total fish catch in the Kapla beel was 12,610 Kg,
9,620 Kg, 7,890 Kg and 5,480 Kg in the year 2008-09, 2009-10, 2010-11 and 2011-12
respectively. The total exotic fish catch percentage in the beel was 13.00% in the year
2008-09 and it reaches to 22.35% in 2011-12 (Table 1.2). From the studies it has been
observed that out of several exotic fish species, Cyprinus carpio is found abundantly in
the beel. In 2008-09 the catch percentage of Cyprinus carpio in the beel was 2.85% of
total fish which is become 4.10% in 2011-12. The fish catch statistics during the study
period indicated that the fishes belonging to the Indian Major Carps has been gradually
decreasing from 23.79% in the year 2008-09 to 18.61% recorded in the year 2011-12
(Figure 1.11 to 1.13). All the indigenous fish group populations are decreasing in the
four years. Once Feather back fishes especially Notopterus chitala was abundant in the
beel and in recent years their production has also been decreasing. Abundance index
(AI) of Common carp in Kapla beel during 2008-12 is shown in Figure 1.14 which has
been increasing year by year. Similarly other indigenous fish species like Aorichthys
aor, Wallago attu, Channa marulius, Channa striatus have also been decreasing
tremendously. The statistical data have clearly indicated that the overall production of
fish in the beel decreasing very rapidly and its last year’s production is less than half of
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the production of four years back. The decreasing is more prominent of fishes belonging
to the major and intermediate groups in the beel and on the other hand, the exotic fishes
especially Cyprinus carpio, Ctenopharyngodon idella, Hypothalmichthys molitrix and
Aristichthys nobilis have been increasing in the beel rapidly.
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Table 1.2. Production of various Fish group and their percentage in the Kapla beel of
Barpeta district of Assam during 2008-2012
Fish/fish
groups
2008-09 2009-10 2010-11 2011-12
Fish
catch
in Kg
% of
fish
catch
Fish
catch
in Kg
% of
fish
catch
Fish
catch
in Kg
% of
fish
catch
Fish
catch
in Kg
% of
fish
catch
Indian Major
Carps
3000 23.79 2060 21.41 1670 21.17 1020 18.61
Murrels 2080 16.49 1650 17.15 1200 15.21 780 14.23
Catfish 1900 15.07 1120 11.64 1150 14.57 930 16.97
Feather ack 1140 9.04 875 9.09 710 9.00 505 9.21
Common carp 360 2.85 280 2.91 250 3.17 225 4.10
Other Exotic
fish
1280 10.15 1230 12.78 1160 14.70 1000 18.25
Misc. 2850 22.60 2405 25.00 1750 22.18 1020 18.61
Total
Indigenous
fish
10970 87 8110 84.3 6480 82.19 4255 77.65
Total exotic
fish
1640 13 1510 15.37 1410 17.87 1225 22.35
Total fish
production
12,610 9,620 7,890 5,480
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Figure 1.10. Production of different fish group in Kapla beel
Figure 1.11. Total fish catch of Kapla beel duing 2008
0
5
10
15
20
25
30
2008-09
Indian Major Carps
Feather back
Misc.
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. Production of different fish group in Kapla beel during 2008
. Total fish catch of Kapla beel duing 2008-12
2009-10 2010-11 2011
Indian Major Carps Murrels Catfish
Common carp Other Exotic fish
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. Production of different fish group in Kapla beel during 2008-12
12
2011-12
Other Exotic fish
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Figure 1.12. Common carp catch in Kapla beel during 2008-12
Figure 1.13. Abundance index (AI) of Common carp in Kapla beel during 2008-12
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Common carp catch in Kapla beel
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�Tab
le 1
.3. A
bundan
ce i
ndex
(A
I) o
f ex
oti
c fi
sh C
om
mon c
arp
in K
apla
b
eel
duri
ng 2
008
-12
Yea
r Ja
n
Feb
M
arch
Ap
ril
May
Ju
ne
July
A
ug
Sep
t O
ct
Nov
Dec
M
ean A
I
2008-0
9
5.5
8
5.2
1
3.2
3
2.1
8
2.0
3
5.0
0
5.3
2
6.5
6
7.1
4
7.7
3
7.2
2
7.6
7
5.4
0
2009-1
0
6.5
5
5.1
8
3.4
6
2.1
7
2.6
2
6.7
5
8.0
9
10.4
5
10.6
6
9.3
8
9.1
1
8.3
2
6.8
9
2010-1
1
6.1
1
7.8
7
4.2
1
3.2
0
2.3
4
7.0
7
7.6
4
8.9
5
10.2
4
10.1
3
11.1
5
9.2
9
7.3
5
2011-1
2
7.1
2
9.6
8
5.1
0
2.2
8
2.0
6
7.5
5
8.7
2
10.1
5
11.2
4
10.0
8
10.5
7
9.4
8
7.8
4
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Invasion of Cyprinus carpio in Urpod Beel
The abundance or invasion of Cyprinus carpio was also surveyed at Urpod beel of
Goalpara district of Assam. The Urpod beel covers an area of about 649.38 ha and is
located between latitudes 26005'05" to 26
006'45" N and longitude 90
034'08" to
90037'45"E. Total wetland area of Goalpara district is 33221 ha that includes 151 small
wetlands (<2.25 ha). River or stream occupies 84.77% of wetlands. The other major
wetland of the district is Waterlogged (7.1%) and Lake/pond (7.0%). The average
annual rainfall in the district is 1614 mm (National Wetland Atlas, Assam). The wetland
is surrounded by the NH-37 in the south, west and north with patches of agricultural
land of villages like Agia, Shyamnagar, Gendera, Garukutia etc (Figure 1.8 and 1.9 E,
F). The eastern side of the wetland is surrounded by villages like Maijunga, Garaimari,
Khurabhasa etc. The beel is connected with another wetland called Patakata beel by a
small drain in eastern side. The Jinari river is passes by the side of the Urpod beel
before meeting the Brahmaputra river. The Jinjiram river originates from the Urpod
Beel, flows parallel to the Brahmaputra and ultimately joins near South Salmara of
Dhubri district. The beel has been included in the list of National Wetland Conservation
Programme under Govt. of India.
Fish catch data of Urpod beel
The Urpod beel is one of the potential wetland within northeastern regions of
India. In the present investigation, it has been observed that the beel contain a rich fish
diversity. The beel covers a huge area, so it is difficult to estimate the total catch of the
beel per year. The fish catch data were collected from the fisher man in different landing
site and data are compiled as percentage in Kg of different fish group from the total
catch (Table 1.4). The fish-catching intensity is higher during winter. The
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commercially important indigenous fish species of the beel are Labeo rohita, Labeo
calbasu, Labeo gonius, Catla catla, Cirrihinus mrigala, Labeo gonius, Notopterus
chitala, Aorichthys aor, Wallago attu, Channa marulius, C. punctatus, Heteropneustes
fossilis, Clarias batrachus, Notopterus notopterus etc. The exotic fish species available
in the beel are Cyprinus carpio, Ctenopharyngodon idella, and Hypothalmichthys
molitrix, Aristichthys nobilis and Clarias gariepinus. The exotic species are available
throughout the year and there has been a considerable increase of catch percent of exotic
fish in the beel. Among the exotic species common carp recorded 6.43% of total catch
in the month February (Table 1.3, Figure 1.15). The common carp has established
breeding populations in the beel. The fish catch record showed that common carp and
grass carp are more abundant other exotic fish. The mean Abundance index of four
exotic fish namely common carp, grass carp, silver carp and bighead carp in Urpod beel
are 14.85, 10.01, 8.53, and 5.74 respectively (Figure 1.16). Thus the common carp is
more abundant exotic fish in the beel.
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Table 1.4 Month wise fish catch (in percentage ) in Urpod beel during 2011
Month Common
carp
catch
Other
exotic
fish
catch
Indian
Major
Carps
Murrels
catch
Cat
fishes
catch
Feather
back
catch
Misc.
Fish
catch
January 4.59 12.11 16.56 14.2 15.18 10.05 27.31
February 6.08 7.56 16.38 19.66 13.56 6.82 30.29
March 6.14 7 15.27 19.12 12.5 2.64 37.29
April 4.11 6.25 12.36 16.32 12.07 1.03 48.1
May 3.40 6.95 15.33 14.29 13.17 3.15 44.04
June 3.35 15.88 17.56 16.39 10.36 3.22 35.04
July 2.15 16.02 22.83 13.16 14.33 4.32 27.14
August 2.68 14.91 21.34 13.11 15.2 4.11 28.91
September 3.3 12.38 24.61 11.08 16 4.23 29.54
October 4.1 13.31 22.39 13.45 14.28 5.44 27.71
November 6.08 11.3 24.62 14.26 14.37 6.2 24.2
December 7.07 9.16 25.4 16.37 16.33 7.89 18.22
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Figure 1.14. Percentage of month wise catch record of four exotic fish and other fishes
in Urpod beel during 2011.
Figure 1.15. Abundance index calculated from catch record of four exotic fish in Urpod
beel during 2011.
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Tab
le 1
.5 A
bundan
ce i
nd
ex (
AI)
of
four
exoti
c fi
sh (
Com
mon c
arp
, G
rass
car
p, S
ilver
Car
p,
Big
hea
d c
arp)
in U
rpod b
eel
duri
ng 2
011
Ex
oti
c fi
sh
Jan
Feb
M
arch
Ap
ril
May
Ju
ne
July
A
ug
Sep
t O
ct
Nov
Dec
M
ean A
I
Com
mon c
arp
12.1
2
10.2
6
10.0
0
8.6
2
12.1
5
15.2
0
16.6
5
18.1
7
20.5
2
16.7
8
12.3
4
15.4
5
14.8
5
Gra
ss c
arp
12.1
0
8.1
6
8.2
6
5.2
0
6.4
4
10.0
0
12.6
7
12.2
5
10.8
1
11.7
2
12.1
5
10.3
8
10.0
1
Sil
ver
Car
p
8.2
0
4.6
8
5.1
0
4.2
1
5.0
5
12.3
5
12.6
2
10.1
5
12.8
4
9.5
8
8.8
6
9.1
8
8.5
3
Big
hea
d c
arp
4.4
8
2.5
6
2.0
7
3.3
7
4.1
3
8.7
9
10.1
7
9.8
5
8.0
0
6.3
3
5.7
3
3.1
8
5.7
4
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Kapla beel of Barpeta district and Urpod Beels of Goalpara district of are two
impotant freshwater lakes/wetlands in Assam which have rich fish diversity and they
harbour almost all freshwater species available in the north eastern region. But this
native fish groups have been decreasing day by day. Immergence of exotic fish may be
a factor for decreasing the native fish species. Few years back the Indian Major Carps
were the most abundant fish group in the Kapla beel and Urpod beel of Assam. But now
a decreasing of total fish production has been observed in Kapla beel from the last four
years’ data. The probable cause of decreasing rate of IMC may be sharing of food and
trophic niche and high fecundity rate of exotic fish. The common carp an exotic
omnivorous fish can reproduce in confined water and this is supposed to be the main
cause of increased production rate of this fish. The species has already established
breeding populations and contributes a large percent of the exploited stock in the rivers
and beel of Assam. The introduction of a non-indigenous species may work
synergistically with other factors, such as water diversions or pollution, to alter the
population and distribution of indigenous species (Nyman, 1991). The breeding
population of common carp can negatively impact native species both directly and
indirectly by competing for food (Arthington, 1991) and habitat. Percentage of high
Abundance Index (AI) has revealed that exotic fish are now abundantly found in the
Kapla beel and Urpod beel of Assam. The exotic fish may cause changes in the
existing aquatic community through competition with native species or predation on
them, as well as through overcrowding or aggressive behaviour. Despite possessing
some attractive culture characteristics, exotic fish species generally becoming invasive
and reduce the availability of local species in natural water bodies and consequently
adversely affecting fish biodiversity and aquatic ecosystems (Lakra et al., 2008). The
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common carp has found to deteriorate the water quality of culture pond and grass carp
has found to destroy paddy field during monsoon (Choudhury et al., 2012). Invasion of
exotic species is the second most important threat to biodiversity after habitat loss.
Species invasions in freshwater lakes have been shown to cause major changes in the
distribution and abundance of endemic organisms, thereby changing the flow of energy
and nutrients (Lodge, 1993; Mills et al., 1994; Ricciardi and MacIsaac, 2000). Alien
species after established in new habitat threatens native biodiversity in that habitat by
causing changes in ecosystem. The native fish species has been decline in alarming
rates due to invasiveness of exotic fish species. A number of exotic fishes are now
available in all major rivers, reservoir and wetland of India (Kumar, 2000). The Yamuna
River and Ganges River system harboured several exotic fish species including common
carp and Nile tilapia (Singh et al., 2010a). The exotics compete with the indigenous
species for food, habitat and even prey upon them, introduce new parasites and diseases,
result in the production of hybirds and cause genetic ‘erosion’ of indigenous species
(Welcomme, 1992). There are many examples of displace of endemic fishes by exotic
fishes in lakes, and can cause changes in food web structure (Mills et al., 1994;
Ricciardi and MacIsaac, 2000). In Chiang Ek Lake of Cambodia the population of
Notopterus notopterus and other fish also have been reported to be declining due to
exotic species tilapia which constitutes up to 80% of the catch (De Iongh and Van Zon,
1993). Once such exotic species are established in a system, eradication is extremely
expensive and in many cases impossible. Hence, before releasing alien species in a
system, it is necessary to estimate the potential success and counterbalance the
ecological aftermath (Zambrano et al., 2006). In India, several exotic species viz.,
Clarias gariepinus, Ctenopharyngodon idella, C. carpio, H. nobilis, H. molitrix, O.
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mossambicus and O. niloticus niloticus were recorded from river Ganga in Uttar
Pradesh with dominancy of C. carpio (NBFGR Annual Report, 2009-2010). There are
numerous examples of the extinction of native species due to introduction of exotic
species (Lodge et al., 2000). Fleming et al. (2000) found that invasions of farm Atlantic
salmon Salmo salar in Norway have the potential for impacting on native population
productivity, disrupting local adaptations and reducing the genetic diversity of wild
salmon populations. Courtenay & Moyle (1992) called fish introductions “crimes
against biodiversity”. According to Minns and Cooley (2000), Introductions of non-
indigenous fishes can reduce diversity and modify local community dynamics in
freshwater systems. Introduced species can cause major changes in community structure
and ecosystem function (Lodge, 1993).
The present survey showed that exotic fish occurrences have been increasing
while the production other fishes are decreasing. Various anthropogenic activities are
responsible for alarming decline of fish populations in the rivers and wetlands. Over
fishing, using of chemicals and poisons, dynamiting, small mesh size fishing gears,
destruction of natural spawning and breeding grounds are main causes of decline of the
freshwater fishes. The exotic fish invasion is thought to be an important cause of
reduction of indigenous fish population. Freshwater fishes are the most imperilled
vertebrate group with a high projected extinction rate. According to Ricciardi and
MacIsaac (2000), freshwater lakes (beels) are among the ecosystems most vulnerable to
species invasion. There is a strong need for public education and awareness about the
impacts of alien species on native fauna and flora. Unless the public is aware of these
impacts, alien species will continue to be spread throughout the world. Proper
monitoring of infestation of exotic fish could save the threatened or endangered fish
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populations in wild water bodies. Detail dietary and behavioural analysis of exotic is
important before and after introduction in new environment or places. The different
exotic fish has apparently increased in recent years and the production figure of
freshwater fish fauna has changed in Assam (India). Introductions were primarily made
for aquaculture but in Assam particularly the intensity of seasonal flood in higher and
every year a large number of cultured fisheries are immerged during flood and thereby
the cultured exotic fish species invaded to natural water bodies such as beels and rivers.
The escape of the exotic fish from aquaculture to wild water may be harmful to the
indigenous aquatic fauna including fish and environment as a whole. To protect the rich
fish diversity in beels of Assam and for conservation of aquatic freshwater ecosystems,
adequate attention should be paid to check the further proliferation of invasive exotic
fish species. The present preliminary investigation has shown that in the Kapla beel of
Barpeta district of Assam the total fish production has been found decrease in the last
four years. But still the catch records detect the increased production of common carp
and other exotic fishes. The catch record and abundance index showed acceleration of
common carp infestation in the beel.
In the above account it has been observed that the Cyprinus carpio population has
been proliferating in India including Assam and the population has established in
different aquatic bodies in India. So, study of phylogeography of Cyprinus carpio
communis was aimed through study of mitochondrial gene. In addition, certain
biochemical parameters were also investigated from distinct genetic haplotypes of the
species.
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AIMS AND OBJECTIVES
In the present investigations Cyprinus carpio communis was selected and samples
were collected from different parts of the country (India) in order to identify the genetic
variations along with variations of some biochemical parameters such as proximate
compositions, amino acid profile and fatty acid profile of the varied strains of the
species. The objectives of the present study are-
1. To study the genetic divergence of Cyprinus carpio communis from different aquatic
bodies through partial sequencing of Cytochrome b gene
2. To analyse the proximate compositions along with amino acid profile and fatty acid
profile of the different haplotypes or variants identified in genetic study from different
regions of the country.
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