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The diversity of cypriniforms throughout Bangladesh: Present status and conservation challenges

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Abstract

Bangladesh is endowed with a vast expanse of inland openwaters characterised by rivers, canals, natural and man-made lakes, freshwater marshes, estuaries, brackish water impoundments and floodplains. The potential fish resources resulting from these are among the richest in the world; in production, only China and India outrank Bangladesh. The inland openwater finfish fauna is an assemblage of ~267 species, the diversity of which is attributed to the habitats created by the Bengal Delta wetlands and the confluence of the Brahmaputra, Ganges and Jamuna rivers that flow from the Himalayan Mountains into the Bay of Bengal. The indigenous fish fauna of Bangladesh's inland openwaters, however, are dominated by the cypriniforms - 87 species under 35 genera. Although representatives are rarely encountered in brackish waters, certain species have adapted to some of the country's most extreme freshwater environments. There are, however, serious concerns surrounding the slow decline in the condition of openwater fish stocks which have been negatively impacted upon through a series of natural and anthropogenic induced changes. These include disturbances resulting from water management programmes including the large scale abstraction of water for irrigation and the construction of water barrages and dams, human activity resulting in the overexploitation of stocks, the unregulated introduction of exotic stocks and pollution from industry. Also, natural phenomena, regular flooding etc cause rivers to continually change course creating complications of soil erosion or oversiltation of waterways. As a consequence, many Bangladeshi species are either critically endangered or extinct. The biodiversity status of many of these have now changed from that listed in the IUCN Red Book almost a decade ago. Assessment is based primarily on the study of specimens maintained in the Fish Museum and Biodiversity Center (FMBC) of Bangladesh Agricultural University and through surveys conducted over the last ten years. The threat to inland openwater biodiversity is countrywide, but that facing cypriniform species is severe. More than 15% of cypriniforms appear to have disappeared; only one or two individuals of a further 20% of species have been found in the last ten years. The needs of Bangladesh's poor fisher community to eat what they catch and lack of a legal legislative framework means the situation can only worsen. Hope, however, is offered through several new conservation initiatives including the establishment of fish sanctuaries at strategic points in rivers and floodplains, concerted breeding programmes and the maintenance of captive stocks and cryogenically stored materials.
In: Species Diversity and Extinction ISBN: 978-1-61668-343-6
Editor: Geraldine H. Tepper © 2009 Nova Science Publishers, Inc.
Chapter 4
THE DIVERSITY OF CYPRINIFORMS THROUGHOUT
BANGLADESH: PRESENT STATUS AND
CONSERVATION CHALLENGES
Mostafa A. R. Hossain* and Md. Abdul Wahab
Faculty of Fisheries, Bangladesh Agricultural University
Mymensingh-2202, Bangladesh
ABSTRACT
Bangladesh is endowed with a vast expanse of inland openwaters characterised by
rivers, canals, natural and man-made lakes, freshwater marshes, estuaries, brackish water
impoundments and floodplains. The potential fish resources resulting from these are
among the richest in the world; in production, only China and India outrank Bangladesh.
The inland openwater finfish fauna is an assemblage of ~267 species, the diversity of
which is attributed to the habitats created by the Bengal Delta wetlands and the
confluence of the Brahmaputra, Ganges and Jamuna rivers that flow from the Himalayan
Mountains into the Bay of Bengal.
The indigenous fish fauna of Bangladesh’s inland openwaters, however, are
dominated by the cypriniforms - 87 species under 35 genera. Although representatives
are rarely encountered in brackish waters, certain species have adapted to some of the
country’s most extreme freshwater environments.
There are, however, serious concerns surrounding the slow decline in the condition
of openwater fish stocks which have been negatively impacted upon through a series of
natural and anthropogenic induced changes. These include disturbances resulting from
water management programmes including the large scale abstraction of water for
irrigation and the construction of water barrages and dams, human activity resulting in
the overexploitation of stocks, the unregulated introduction of exotic stocks and pollution
from industry. Also, natural phenomena, regular flooding etc cause rivers to continually
change course creating complications of soil erosion or oversiltation of waterways. As a
consequence, many Bangladeshi species are either critically endangered or extinct. The
* Corresponding author: marhossain@yahoo.com
Hossain M. A. R., and Wahab M. A. (2010) The diversity of cypriniforms throughout Bangladesh: present
status and conservation challenges. In: Species Diversity and Extinction. ISBN: 978-1-61668-343-6, 448 p.
Geraldine H. Tepper (ed). Nova Science Publishers Inc., New York, USA. 143-182 pp.
Mostafa A. R. Hossain and Md. Abdul Wahab 144
biodiversity status of many of these have now changed from that listed in the IUCN Red
Book almost a decade ago.
Assessment is based primarily on the study of specimens maintained in the Fish
Museum and Biodiversity Center (FMBC) of Bangladesh Agricultural University and
through surveys conducted over the last ten years. The threat to inland openwater
biodiversity is countrywide, but that facing cypriniform species is severe. More than 15%
of cypriniforms appear to have disappeared; only one or two individuals of a further 20%
of species have been found in the last ten years.
The needs of Bangladesh’s poor fisher community to eat what they catch and lack of
a legal legislative framework means the situation can only worsen. Hope, however, is
offered through several new conservation initiatives including the establishment of fish
sanctuaries at strategic points in rivers and floodplains, concerted breeding programmes
and the maintenance of captive stocks and cryogenically stored materials.
1. INTRODUCTION
Bangladesh is situated in the northeastern part of the South Asia and lies between 20o34'
and 26o38' North longitudes and 88o01' and 92o41' East latitudes. The country is bordered by
India on the West, North and North-East (2,400 kilometer land frontier) and Myanmar on the
Southeastern tip (193 km land and water frontier). On the south is a highly irregular deltaic
coastline of about 710 kilometers, fissured by many rivers and streams flowing into the Bay
of Bengal. The territorial waters of Bangladesh extend 22 km, and the exclusive economic
zone of the country is 370 km. The total landmass of the country is about 144,400 km2 and
extends 820 kilometers north to south and 600 kilometers east to west. The country stretches
out at the junction of the Indian and Malayan sub-regions of the Indo-Malayan zoogeographic
realm.
Formed by a deltaic plain, Bangladesh is virtually the only drainage outlet for a vast
complex river basin made up of the Ganges (local name the Padma), the Brahmaputra and the
Meghna rivers and their network of tributaries. The Padma unites with the Jamuna (main
channel of the Brahmaputra) and later joins the Meghna to eventually empty into the Bay of
Bengal. The alluvial soil deposited by these rivers every year has created some of the most
fertile plains in the world. Most parts of the delta are less than 12 metres above the sea level,
and it is believed that about 50% of the land would be flooded if the sea level rise by a metre.
Straddling the Tropic of Cancer, Bangladesh has a tropical monsoon climate characterised by
heavy seasonal rainfall, high temperatures, and high humidity. There are three broad
physiographic regions in the country. The floodplains occupy about 80%, terrace about 8%
and hills about 12% of the land area (Table 1). Moreover, it is a country dominated by
wetland having more than 50% of its territory under true wetlands that is freshwater marshes,
swamps, rivers estuaries and the world’s largest contiguous mangrove forest - the
Sundarbans.
Bangladesh has a total inland water area of 6.7 million ha of which 94% is used for open
water capture fishery and 6% for closed water culture fishery (Table 2). The inland open
water fishery resources have been playing a significant role in the economy, culture, tradition
and food habit of the people of Bangladesh. Rivers and their ramified branches cover about
479,735 ha area of land. Seasonal floodplain expands over a massive 5.5 million ha for 4-6
months of the year. Inland open water also contains estuarine areas with semi-saline waters
The Diversity of Cypriniforms throughout Bangladesh: Present Status 145
(0-10 ppt), huge number of beels (natural depressions often with permanent area of water)
and haors (bowl-shaped deeply flooded depressions) in the north and east and the manmade
Kaptai lake – the largest lake of the country in the south. The country is blessed with 0.26
million of closed waters in the form of ponds, ditches, oxbow lakes (channel of dead rivers)
and brackish water farms. More than 2 million people directly or indirectly depend on inland
capture fisheries for their livelihood.
Fish have been an integral part of life of the people of Bangladesh from time
immemorial. Many aspects of the Bangladeshi culture, economy and tradition are based
around fishing and fish culture activities. The sector plays a vital role in the country’s
economy, employment generation, animal protein supply, foreign currency earning and
poverty alleviation. Fish is a natural complement to rice in the national diet, giving rise to the
adage “Maache-Bhate Bangali”, literally meaning – ‘fish and rice make a Bangladeshi’.
Fisheries, second only to agriculture in the overall economy of Bangladesh, contribute nearly
5.0% to the gross domestic product (GDP), 23% of gross agriculture products and 5.71% to
the total export earnings (DoF 2008). It accounts for about 63% of animal protein intake in
the diet of the people of Bangladesh (DoF 2005). The fisheries sector provides full-time
employment to an estimated 1.2 million fishermen and an estimated 10 million households or
about 64% of all households are partly dependent on fishing, e.g. part time fishing for family
subsistence in flooded areas. Another 10% poor and middle class people are engaged in part-
time fishing, aquaculture, fish seed production and collection of shrimp and prawn seed, fish
handling, processing and marketing, net making, input supply etc.
The people of Bangladesh largely depend on fish to meet their protein needs in both the
rural and urban areas. Until 70s, there was an abundance of fish in the natural waters of the
country to well-satisfy the demand. In recent years, however, capture fish production has
declined to about 50%, with a negative trend of 1.24 % per year (Ahmed 1995). Despite the
constant depletion of the natural waterbodies for years, Bangladesh still holds one of the most
diverse inland fisheries in the world. However, the availability of many fish species has been
drastically declined, and many are either critically endangered or extinct. On the migration
journey to the floodplains, and the return to rivers, fish now face many blockage and danger,
which seriously interfere with the breeding and resulting recruitment.
Table 1. Major physiographic areas of Bangladesh
Description Area (km2) % of total area
Rivers, canals, streams 8,300 5.76
Estuarine, brackishwater water-bodies 1,828 1.27
Floodplains 112,010 77.76
Wetlands 2,930 2.03
Freshwater ponds and tanks 794 0.55
Artificial lakes 906 0.63
Hill areas 17,286 12.00
Total Bangladesh 144,054 100
Source: Hoq (2009)
Mostafa A. R. Hossain and Md. Abdul Wahab 146
Table 2. Extent of different type of water areas
Types of water areas Area (ha)
a) Inland open waters
1. Rivers (during dry season)
The Ganges 27,165
The Padma 42,325
The Jamuna 73,666
The Meghna (upper) 33,592
The Meghna (lower 40,407
Other rivers and canals 262,580
2. Estuarine area 551,828
3. Beels and haors 114,161
4. Kaptai Lake 68,800
5. Inundated flood plains (seasonal) 5,486,609
Total 6,701,133
b) Closed waters
1. Ponds and ditches 146,890
2. Baors (oxbow lakes) 5,488
3. Brackish water farms 108,000
Total 260,378
Source: FRSS-DoF 2008
2. THE KEY WATERBODIES AND THE STATUS
The inland open water fishery of Bangladesh is composed of highly diverse and unique
aquatic systems. It has an extensive network comprising of floodplains, large and small rivers,
beels, haors and baors offering tremendous scope and potential for fish production. It has
also large impounded water areas in manmade ponds, ditches, borrow pits, lakes and
enclosures (DoF 2005).
2.1. The Floodplain
Floodplains are relatively low laying land area, bordering rivers and seasonally over-
flooded by overspill from the main river channel. There are two distinct flooding patterns, one
resulting in flow direction from the floodplains to the rivers (from flush flood due to local
rainfall) and the other from the rivers to the floodplains (river overspill due to the heavy
rainfall in the upstream). The ecodynamics of floodplain are influenced by the river water
incursion and retreat and the timing and intensity of monsoon. There are great differences in
the area flooded from year to year, and this greatly influences the population dynamics of
many fish species.
The seasonally flooded area is highly productive for growth of fish and other aquatic
animals. During the dry season, as pasture land, the floodplain receives nutrients in the form
The Diversity of Cypriniforms throughout Bangladesh: Present Status 147
of animal dropping and rotting vegetation. As the monsoon approaches the accumulated
nutrients rapidly enters into the solution combined with river-borne silt, led to an upsurge of
productivity resulting in rapid growth of plants and other forms of aquatic biota. This
productivity phase offers an ideal condition for feeding and breeding of many riverine fishes
and other aquatic animals which migrate to floodplain with the rising waters. Floodplains
inundated during monsoons are nutrient rich and play a significant role as nurseries for larvae
and juvenile of many fish species (Junk et al. 1989). A large number of fresh water fish
species migrate from rivers and beels to floodplains for breeding and grazing and are
harvested by the rural professional and amateur fishers. The floodplains are essential for most
of the rural people of Bangladesh for their livelihood.
The floodplains are very rich in both floral and faunal diversity and harbour a large
number of finfish, crustaceans, molluscs amphibians, reptiles and a large number of aquatic
vegetation. FAP-6 (1992) recorded 154 finfish and prawn in the floodplain of the northeastern
region of the country. FAP-17 (1994) documented 89 finfish and prawn species in the
floodplain of Tangail. Major species under the two studies reported were Indian major carps,
several species of minor carps and loaches belonging to the Order Cypriniformes.
Fish production in 2006-07 was 819,446 mt in the floodplains, which was 77.29% of total
inland capture fish production and 51.32% of the total inland fish production. The rate of
present floodplain fish production in Bangladesh is 289 kg ha-1 year-1 which is higher than the
production in the floodplains of many neighbouring countries (DoF 2008).
Since 1970, the annual flooding of approximately 2-3 million ha of floodplain has been
either controlled or prevented altogether by means of sluice gates or pumps positioned along
earth embankments or levees (ESCAP 1998). This reduction in area is believed to be one of
the major reasons for declining floodplain fisheries in Bangladesh (FAP 17 1994). Over-
exploitation of inland fish stocks has also been reported (Graaf et al. 2001).
2.2. The Rivers
Bangldesh is a riverine country. It has numerous rivers and their tributaries (Figure 1).
The Ganges, the Brahmaputra and the Meghna are the mighty rivers. The three rivers along
with their innumerable tributaries form one of the richest habitats of fishes in the Indian
Subcontinent. In addition to three main rivers, the other main rivers are the Karnafuli,
Matamuhuri, Halda and Sangu in the southern Chittagong sub-region. The major rivers are
the Surma, Kushiara, Kangsha and Someshwari in the north-east region and the Tista,
Korotoa, Atrai, Bangalee, Mohananda in the north-west. The total length of the network of
about 310 rivers in Bangladesh together covers more than 24,000 km with a catchment area of
1,031,563 ha. Annual flooding of the rivers inundates about 70% of the total land surface.
The total annual discharge passing through the rivers system into the Bay of Bengal reaches
up to 1,174 billion m3 (Banglapedia 2004).
The rivers are not evenly distributed in the country. For instance, the numbers and size of
the rivers gradually increase from the northwest of the northern region to the southeast of the
southern region. All the rivers, except those of Chittagong hilly sub-region, belong to three
major river systems, the Ganges, the Bhramaputra and Meghna. In the global context, the
Brahmaputra is the 22nd longest (2,850 km) and the Ganges is the 30th longest (2,510 km)
Mostafa A. R. Hossain and Md. Abdul Wahab 148
river in the world. Rivers and canals roughly cover 5.8 % of the total area of the country.
According to (BWDB 2005) 57 of the rivers are trans-boundary – 54 originate from India and
3 from Myanmar. The river system of Bangladesh is divided into 6 hydrological regions as
shown in Table 3.
Figure 1. Map of Bangladesh showing main rivers and their tributaries (Banglapedia 2004).
The Diversity of Cypriniforms throughout Bangladesh: Present Status 149
Table 3. Hydrological regions of river system in Bangladesh
Hydrological region Number
of rivers Length
(km) Catchments
area (km2)
North West Region 96 4,908 63,718
North Central Region 20 1,311 18,404
North East Region 55 3,250 47,616
South East Region 24 1,320 10,068
Eastern Hilly Region 17 1,131 6,253
South West Region 98 4,969 35,576
Total 310 16,889 1,81,635
Source: BWDB (2005)
During rainy season, the rivers carry high amount of silt which makes the water turbid. In
winter, the water level decreases and water becomes clear. The depth of the coastal rivers
usually ranges from 2 m to 5.5 m and reaches up to 36.5 m near the Bay of Bengal. Salinity of
about 1 ppt extends nearly 56 km upstream in these rivers.
The rivers of Bangladesh have a great importance in respect of fisheries and other
hydrological and navigation benefits. Rivers are the migratory routes of fishes with adjacent
floodplains and vice-versa. Among the riverine fishes, Cypriniform - carps, barbs and
minnows and loaches are very important. Many of the Cypriniforms migrate upstream
(floodplain) in order to spawn in nutrient rich water, where they feed on plankton and grow
(Rahman 2005). At the end of monsoon the adult and young fishes escape to the rivers and
most likely to the adjacent deeper beels to avoid harsh condition of the floodplain during dry
season.
The hill-streams in the north and north-east are swift flowing with clear water. Many of
the Cypriniform mainly loaches inhabiting the hill-streams usually have modified paired fins
and grooved thoracic disk, which acts as adhesive apparatus. The fishes with compressed
head and horizontally placed pectoral and pelvic fins can easily stick to the bottom and do not
swept away in swift flowing water. Among the riverine Cypriniform that inhabit the hill-
streams are the members of the genera – Nemachilus, Schistura, Balitora and Psilorhynchus
under the Families of Balitoridae and Psilorhynchidae. The fish species of the Genera -
Garra, Barilius and Raiamas under the Family Cyprinidae are also available in these streams.
2.3. The Beels
The beel is a Bengali term used for relatively large surface, static waterbody that
accumulates surface run-off water through an internal drainage channel (Banglapedia 2004).
This type of shallow, seasonal waterbody is common in low-lying floodplain areas throughout
Bangladesh. The total area of beels in Bangladesh was estimated to be 114,161 ha, occupying
27.0% of the inland freshwater (Ahmed et al. 2007). The number of beels in the north-eastern
part of the country recorded was 6,034 having an area of 69,870 ha (Bernaesek et al. 1992).
The most famous beel in the country known as the Chalan beel is located in the north-
west. The other major beels in this region are Hilna, Kosba, Uthrail, Manda, Sobna and Beel
Mansur. In central region, Arial beel and Balai beel now lost their importance as natural fish
Mostafa A. R. Hossain and Md. Abdul Wahab 150
habitat. Other important beels in this region are Chanda, Boro, Mollar and Tungipara beels.
There are many beels in the south and south west and the notable are Chapaigachi, Garalia,
Panjiapatra, Chenchuri and Dakatia beels.
The beels are parts of riverine floodplain formed due to changes in the river course or
strengthening of river embankments for controlling flood (Saha et al. 1990). The beel water is
very productive in terms of fertility and nutrient, full of organic debris and organic vegetation
and provide food and shelter to many larvae and juvenile as well as adult fishes and other
aquatic organisms (Graff 2003).
Beels are mainly of two types: a) perennial beel (retain water throughout the year) and b)
seasonal beel (dried up in the dry season but during the rains expand into broad and shallow
sheets of water). The perennial beels are the dry season refuges (over wintering ground) of
many fish species. These waterbodies are very favourable natural habitat of small and large
indigenous fishes to feed, grow and breed during monsoon as well. Among the various
parameters that influence the beel ecosystem are depth, nature of catchments area or river
basin, precipitation and duration of connection to river (Sugunan and Bhattacharjya 2000).
Beels are generally rich in fisheries resources in Bangladesh and provide considerable
fish production of the country. Some important beels in greater Sylhet and Mymensingh
region are known as “mother fishery”. Beels play an important role in the fish production as
well as shelter of brood fish in the country. The beels of Bangladesh comprise about 2.82% of
total aquatic resources which supplied 77,524 mt of fish in 2007-08. Beel fishery of
Bangladesh is being deteriorating day by day due to over fishing, uncontrolled use of
chemical fertilizer and insecticide, destruction of natural breeding and feeding grounds,
harvesting of wild brood fishes and for many other causes (Azher et al. 2007).
2.3.1. Chalan beel
Chalan beel is the largest and most important watershed in the North Central Bangladesh.
It comprises of a series of depressions interconnected by numerous channels to form more or
less one continuous sheet of water during monsoon covering an area of about 375 km2. The
watershed serves about five million people predominantly through fisheries and agriculture.
Though far from its past glory, Chalan beel is still an abode of large variety of ichthyofauna
with a huge importance in local economy and people’s livelihood.
During the dry season, the water area decreases down to 52-78 km2 and looks like a
cluster of small beels of different sizes. Besides being a giant junction of a number of water
ways, the beel also served a springboard where many rivers flowed further south and east to
meet finally with the river Padma and the Brahmaputra (Iqbal 2006).
The Chalan beel comprised of 21 rivers and 93 small beels and their floodplains, 12,817
ponds and 214 borrow pits. There are 21 rivers streaming into the Chalan beel which cover a
total area of about 709 ha and 3,300 ha in dry and monsoon, respectively. Most of the rivers
and beels are at the risk of partial or total degradation due to manifold reasons like
agricultural encroachment, siltation along with other anthropogenic activities. The critical dry
out condition (0-5% of the monsoon size) was observed in 83% of the rivers and 68% of the
beels in the lean season (Hossain et al. 2009)
Hossain et al. (2009) documented 114 finfish species from 29 families in the largest beel
of Bangladesh – the Chalan beel. Among the thirty nine Cyprinifoms in the Chalan beel -
thirty one species were under Cyprinidae one under Balitoridae, six under Cobitidae and one
The Diversity of Cypriniforms throughout Bangladesh: Present Status… 151
under Psilorhynchidae. The most abundant fish species were two Cypriniform - Puntius
sophore and Puntius ticto.
The number of fishers in the Chalan beel has been changed over time with a 58%
reduction from 1982 to 2006 (Table 4). They either left their profession or migrated
elsewhere in Bangladesh. Presently there are 75,000 professional and subsistence fishers in
the Chalan beel area maintaining their livelihoods from this resource directly or indirectly.
Most of the fishermen families have been leading a sub-human life, many have been
catching eggs, spawns, fry, undersized fish and broods indiscriminately which have resulted
in scarcity of fish in the beel area. In this situation, almost all the fishermen, who used to earn
their livelihood by fishing, are now facing hardships as there is virtually no fish in the waters
in most of the time of the year.
It has been reported that the fish production in Chalan beel reduced by 31% and 52% in
1992 and 2002, respectively, as compared to the production in 1982 (Figure 2). Fish species
availability and production are tightly bound to the pattern of the flooding which takes place
during the monsoon in the Chalan beel (Ahmed 1991).
Human interferences including some development interventions such as construction of
roads, dams and embankments and human settlement adversely affected the aquatic
ecosystem and habitat of fish population in the Chalan beel by obstructing their migratory
routes. Therefore, the breeding of migratory species has been interrupted which hampered
natural recruitment of fish in the beel. Though, this is not the case for non-migratory resident
fish spawners, over-exploitation and drying up of the waterbody perhaps responsible for
overall low abundance of many species.
Table 4. Changes in number of fishermen over the years in Chalan beel
Year
Fishermen
category 1982 1992 2002 2006
Professional 53,446 46,534 33,445 22,316
Subsistence 1,23,615 1,06,335 73,612 52,684
Total 177,061 152,869 107,057 75,000
Source: Hossain et al. (2009)
Figure 2. Fish production tends in Chalan beel (Hossain et al. 2009)
Mostafa A. R. Hossain and Md. Abdul Wahab 152
2.4. The Haors
The haors are back swamps or bowl-shaped depressions between the natural levees of
rivers, or in some cases, much larger areas incorporating a succession of these depressions.
The Bengali word haor basically derived from the word sagor (literally meaning sea) and
dialectically sagor - saior - haor has been evolved (Khan et al.1990).
In terms of
morphology and hydrology, a haor can be subdivided into three major areas, the piedmont
area around the hill foot, the floodplains and the deeply flooded area (Hossain and Nishat
1989). The haors vary in size from as little as a few hectares to thousands of hectares. The
haors flood to a depth of as much as 6 m during the rainy season and in many cases two or
more neighboring haors unite to form a much larger water body.
Greater part of the north east region of Bangladesh is characterized by the presence of
numerous large, deeply flooded depressions, known as haors, between the rivers. There are
altogether 411 haors (47 major and large sized) comprising an area of about 8,000 km2
dispersed in the north-eastern Sylhet and Mymensingh districts. The haor basin is bounded by
the several Indian states - hills of Meghalaya on the north, hills of Tripura and Mizoram on
the south, and the highlands of Manipur on the east.
The two big rivers in the region – Surma and Kushiyara in association with several
smaller hill-streams - Manu, Khowai, Jadhukata, Piyangang, Mogra and Mahadao form the
dense network and supply the massive water to the haors. The rivers are primarily responsible
for providing inputs - rainwater and sediment load to the haors. The haors remain flooded for
about 7 to 8 months. During the rainy season, the haors look just like vast inland sea and the
villages within appear as islands.
In greater Sylhet the most prominent haors are Saneer, Hail, Hakaluki, Dekar, Maker,
Chayer, Tangua and Kawadighi. In consideration of the environmental importance and
heritage, the government has decided to save the Tanguar haor (9,500 ha) by symbolizing it
as an internationally critical environment area under the Environmental Protection Law of
1995 and registered as a wetland of international importance (Ramsar site, site no. 1031,
declared in 10.07.2000) under Ramsar Convention. The location-wise principal haor systems
are given in Table 5.
The haors are considered to be the most productive wetland resources of Bangladesh.
The basin supports a large variety of aquatic biodiversity and works as natural reservoir. In
past, most of the haor basin was covered with swamp forests and reed lands had a
characteristic feature of flooded forests made the entire haor a suitable habitats for small and
large fish and other aquatic animals. Livelihoods of the villagers living in and around the haor
were largely dependent on the haor resources for food, nutrition, grazing, boating, housing,
income and other forms of livelihood security.
The haors serve as the natural brood stocks of many indigenous fishes including large
carps and catfishes. With the advent of the dry season water recedes, the relatively elevated
parts of haor area begin to dry when paddy is raised on the dried upland areas. The relatively
depressed areas, however, remain under water where fishes take shelter. The haors also act as
important breeding and spawning ground of many fishes. There are a total of 141 finfish
species found in the haors. The important Cypriniform fishes available in the haors are -
Labeo rohita, L. gonius, L. boga, L. calbasu, Catla catla, Cirrhinus mrigala, C. reba,
Crossocheilus latius, Bengala elanga, Rasbora rasbora, Osteobrama cotio cotio and Tor tor.
The Diversity of Cypriniforms throughout Bangladesh: Present Status… 153
Table 5. The principal haor systems of Bangladesh
Location Name of the haors
Eastern and lowest part of the basin,
Mymensingh Baram, Banka, Habibpur, Maka,
Makalkandi and Ghulduba
Foot of the Meghalaya Hills Tangua, Shanir, and Matian
East of the Tangua system Dekhar, Pathar Chanli, and Jhilkar
Eastern rim of the basin Jamaikata, Mahai, Nalua, and Parua
Central Sylhet lowlands Hakaluki, Chatal Bar, Haila,
Kawadighi, Pagla and many smaller
Tarap and Banugach hill ranges in
the southeast Hail
South of the basin Dingapota, Ganesher, Tolar,
Anganer, Bara, and Humaipur
Kishorganj Etna and Sania
East Mymensingh Khaliajhuri
Source: NERP (1995)
2.5. The Baors
In the southwest region of Bangladesh there are a number of meandering rivers changed
their courses, part of the old course got silted up and cut-off from the main course. As a result
horseshoe shaped oxbow lakes known as baor was created. A baor apparently looks like a
lake, but unlike lakes, it remains connected with original river through channels during
monsoon. This way, the baors annually receive fresh supply of riverine water carrying fry,
fingerlings and adult fishes and other aquatic animals. Baors are very important wetlands of
Bangladesh and support a wide range of aquatic flora and fauna.
There are more than 87 baors in Bangladesh covering an area of 5,488 ha (DoF 2008).
Most of the larger baors are in southwestern Jessore region. The baors range in size from
about 25 ha to a maximum of 500 ha (Bhuiyan and Choudhury 1997). The important baors of
the country are Arial, Bahadurpur Baluhar, Bookbhara, Harina, Habullah, Rustampur,
Ichhamati, Jaleshwar, Jogini Bhagini, Joydia, Kannadah, Kathgara, Khedapara, Marjat,
Pathanpara, Rampur, Sagarkhali, Sirisdia and Sonadia.
The baors are an abode of small and large indigenous fish species. Most of the fish
species breed and thrive in the baors throughout the year. The waterbodies are shelters and
breeding grounds for fishes, amphibians, reptiles and a gamut of aquatic invertebrates. The
baors support a continuous daily harvest of subsistence and commercial fishing round the
year. About 50 species of indigenous fishes belonging to 31 genera and 20 families could be
found in a baor. All the baors are now under a heavy fishing pressure. The construction of
dams and other flood control structures have reduced the natural recruitment and contributed
to stock depletion. The total catch area in the baors is about 5,488 ha and the annual
production is about 2,460 mt (DoF 2008).
Mostafa A. R. Hossain and Md. Abdul Wahab 154
2.6. The Ponds and Ditches
There are more than 1.3 million ponds having a water surface of 0.3 million ha in the
country (DoF 2008). Though in past ponds were constructed for washing, bathing and
irrigation purposes, recently, many ponds are being constructed absolutely for fish culture
purposes. There are two types of ponds on the basis of water retention capacity – the
perennial ponds - contain water round the year and the seasonal ponds - contain water at a
certain times or seasons (mainly in monsoon).
The pond culture fisheries have always been considered as being crucial for the
livelihoods of the most vulnerable people of the country. In addition, it is also good for the
fish diversity as it encourages the domestication of wild fishes through artificial breeding and
rearing in the captivity. Selective aquaculture, however, could be detrimental for fish
biodiversity as the culture technologies advice farmers to remove all small indigenous fishes
from the ponds before releasing the fry of target fish. Farmers often use piscicide and
insecticide to clean their ponds. The practice has been going on in Bangladesh since the carp
polyculture being introduced in late 70s. As a result, though harvests from fish culture are
rapidly increasing, the catches of small fishes are declining at an alarming rate.
The fish production from ponds and ditches in Bangladesh in the year 2007-08 reached to
866,049 mt with an average production of 2,839 kg ha-1 (DoF 2008). The major culture
species are the Cypriniforms – Labeo rohita, L. bata, Cirrhinus mrigala and Catla catla.
Labeo calbasu and Cirrhinus reba are also being cultured in smaller scale. The small
indigenous Cypriniforms used to be abundantly available in the past in most of the homestead
ponds, now-a-days seldom found are Amblypharyngodon mola, Salmostoma phulo, Esomus
danricus, Osteobrama cotio cotio, Puntius sophore and Puntius ticto.
2.7. The Kaptai Lake
There are only three true natural lakes in the country. Rainkhyongkine lake and Bogakine
lake are located in the Chittagong Hill Tracts, and a lake named Ashuhila beel at the northern
end of the Barind Tract. The largest man-made lake in South Asia is Kaptai lake of 68,800 ha
(surface area – 58,300 ha). The H-shaped Kaptai lake, the only major reservoir in Bangladesh
was created from the construction of dam across the river Karnafuli near Kaptai town in 1961.
It has drowned almost the whole of the middle-Karnafuli valley and the lower reaches of the
Chengi, Kasalong and Rinkhyong rivers. Shoreline and the basin of Kaptai Lake are very
irregular. The volume of the lake is 524,700 m3 with a mean depth 9 m (maximum depth – 32
m and mean water level fluctuation - 8.14 m). Though the lake was created primarily with a
vision to generate hydroelectric power, it substantially contributes to the national economy
through freshwater fish production, navigation, flood control and agriculture. The lake is
confined within the hill district of Rangamati and embraces sub-districts of Rangamati Sadar,
Kaptai, Nannerchar, Langadu, Baghaichhari, Barkal, Juraichhari and Belaichhari
In 2007-08 fish production in Kaptai lake was 8,248 mt with an average of 120 kg ha-1.
At the early stage of the creation of lake, Indian major carps were the dominant species of
about 60% of total catch, which is reduced to 5.69% in 2007-08. Presently the major catch in
the Kaptai lake is kachki (Corica soborna) - 29.90% followed by chapila (Gudusia chapra) -
The Diversity of Cypriniforms throughout Bangladesh: Present Status… 155
29.81%, respectively. Halder et al. (2002) recorded 66 species of indigenous fish in the lake.
The major Cypriniforms available in the lake are Catla catla, Cirrhinus mrigala, Lebeo
rohita, L. calbasu and L. goinus and Puntius sarana.
There are about 10,000 people directly or indirectly involved in fishing and fishery
related activities at the reservoir. The reservoir has also provided income and employment
opportunities to people, particularly in the areas of drying and retail marketing of the fish. As
the local poor people remove the protective vegetation around the lake, the rocks are exposed
to the monsoon rains and thus eroded easily. This results in regular landslides, and the loose
rocks is washed down the slopes and carried by rivers into the lake. As a result, the lake is
silting up rapidly. By early 1990s, in its 30-year existence, it had already lost 25% of its
volume due to siltation.
3. AQUATIC FAUNA OF BANGLADESH
Bangladesh is a transitional zone of flora and fauna, because of its geographical settings
and climatic characteristics. It is natural that the water resources of the existing extent and
magnitude should harbour and support populations of a large variety of vertebrate and
invertebrate aquatic living organisms. This country is rich in fish and aquatic resources, and
other biodiversity (Table 6). Bangladesh’s water bodies are known to be the habitat of 267
freshwater fishes, 475 marine fishes, 23 exotic fishes and a number of other vertebrates and
invertebrates. Among the documented aquatic fauna, finfish tops the list, followed by the
crustaceans and molluscs (Figure 3).
Table 6. Diversity of aquatic animals in Bangladesh water
Number of Species
Animal group Freshwater Marine
Finfish 267 475
Shrimp - 41
Prawn 20 -
Mollusc 26 336
Crab 4 11
Lobster - 6
Frog 10 -
Turtle & tortoise 24 7
Crocodiles 2 1
Snakes 18 6
Otters 3 -
Dolphin 1 8
Whale - 3
Total 375 894
Source: Ahmed and Ali (1996), Ali (1997) and Banglapedia (2004).
Mostafa A. R. Hossain and Md. Abdul Wahab 156
Crustacean
and Mollusc
35.0%
Amphibian
0.8%
Mammal
1.2%
Reptile
4.6%
Finfish
58.5%
Figure.3. Percentages of major aquatic animal groups of Bangladesh.
Major carp
30.0%
Other inland fish
36.1%
Exotic carp
16.4%
Minor carp
0.6%
Hil
sa
4.6%
Other live fish
3.3% Snakehead
5.8%
Catfish
3.3%
Source: FRSS-DoF 2008.
Figure 4. Group-wise catch of freshwater fishes (2006-07).
Major carp - Rui, Catla, Mrigal and Kalibaus; Exotic carp - Silver carp, Common carp, Mirror carp and
Grass carp; Minor carp – Gonia, Reba and Bata; Catfish - Rita, Boal, Pangas, Silong and Air;
Snakehead - Shol, Gazar and Taki; Other live fish - Koi, Singh and Magur; and Other Fish - all other
fishes
The total inland open water fish production of Bangladesh in the year of 2006-07 (July-
June) was 1.783 million tons. The catch was dominated by major carps (30%) followed by
exotic carps (16.4%) and snakeheads (5.8%) (Figure 4).
4. THE CYPRINIFOM FISHES
The Oriental region (i.e. monsoonal Asia, south of 30oN) hosts over 3,500 species under
105 families of freshwater finfishes. Cypriniforms are the most diverse group of fishes in
most of the Asian countries like Bangladesh, India, Nepal, Pakistan, Myanmar, Thailand,
Vietnam, Cambodia, Indonesia and Malaysia. In terms of generic richness, the top two fish
families in Asia are Cyprinidae (147 genera) and Balitoridae (38 genera) under the Order
The Diversity of Cypriniforms throughout Bangladesh: Present Status… 157
Cypriniformes (Dudgeon 2002). Globally the Order contains 6 families (Balitoridae,
Catostomidae, Cobitidae and Gyrinocheilidae under Super Family Cobitoidea and Cyprinidae
and Psilorhynchidae under Super Family Cyprinoidea), 320 genera and more than 3,250
species.
In Bangladesh, there are 267 species of freshwater bony fishes under 156 genera and 52
families (Table 7). Among the freshwater fishes, the three Orders that dominate are
Cypriniformes, Siluriformes and Perciformes. More than one third of the total freshwater fish
belong to the three Orders – Cypriniformes (33%), Siluriformes (22%) and Perciformes
(24%). The major fish groups available in the country’s freshwater are major carps, large
catfishes, minor carps, small catfishes, river shads, snakeheads, freshwater eels, feather backs,
parches, loaches, anchovies, gobies, glass fishes, mullets, minnows, barbs and flounders.
The diversity in size, shape, colors, habitat preference, feeding and breeding of the
freshwater fishes of the country is high. If one considers only the size, there are very small
fish (maximum length - only a few cm. Danio rerio, Oryzias dancena etc.) and also there are
large fish (maximum length – more than two meters, Wallogo attu, Bagarius bagarius etc).
The Cypriniformes is the largest order of freshwater fishes in Bangladesh and includes
carps, barbs, loaches and minnows. This is usually the dominant group of freshwater fishes,
very rarely entering brackish water, and adapted to the most extreme freshwater environment.
Members of this order have compressed head and body and most species lack fin spines. They
do not have any adipose fin. The mouth is usually more or less protractile. Cyprinifoms also
have a weberian apparatus that connects the swim bladder to the auditory system (the inner
air) through a chain of small bones to facilitate an acute sense of hearing. The presence of the
weberian apparatus is one of the most important and phylogenetically important
distinguishing characteristics of the Cypriniformes and some other fishes. Body of the
Cypriniform fishes are either with cycloid scale or naked and heads are scaleless.
Table 7. Number of freshwater fish species, genera, families and orders present in
Bangladesh
Order Family Genus Species
Anguiliformes 5 6 8
Osteoglossiformes 1 2 2
Elopiformes 1 1 1
Clupeiformes 3 12 18
Cypriniformes 4 35 87
Siluriformes 13 36 59
Cyprinodontiformes 1 1 1
Syngnathiformes 1 2 3
Synbranchiformes 2 4 6
Perciformes 15 46 65
Beloniformes 3 5 7
Pleuronectiformes 3 4 7
Tetraodontiformes 1 2 3
Total = 13 52 156 267
Mostafa A. R. Hossain and Md. Abdul Wahab 158
Table 8. The key distinguishing characters of the four Cypriniform families available in
the freshwaters of Bangladesh
Characters Psilorhynchidae Balitoridae Cobitidae Cyprinidae
Pectoral fin Inserted horizontally Pectoral and pelvic inserted
laterally
Pectoral fin
ray At least two unbranched rays All rays branched or only
outermost anterior ray unbranched
Body shape Greatly arched
dorsally and
flattened ventrally
Depressed Worm-like to
fusiform Usually
laterally
compressed
Barbel Absent 3 or more pairs 3 - 4 pairs 1 - 2 pairs or
absent
Air bladder Greatly reduced;
free in the
abdominal cavity
Large; partly
enclosed in a
bony capsule - -
Spine - -
Erectile spine
near eyes No suborbital
or preorbital
spine
Pharyngeal
teeth - -
1 row 1-3 rows
Modified from Talwar and Jhingran (1991)
Among the six families of Cypriniformes available worldwide, fishes of four families
(Balitoridae, Cobitidae, Cyprinidae and Psilorhynchidae) are available in Bangladesh. Under
the four families, there are 35 genera and 87 species reported from the freshwaters of
Bangladesh. The four families can be separated by a number of key characters (Table 8).
4.1. Family Psilorhynchidae
The family only has one genus – Psilorhynchus and the members are found in primarily
in the Gangetic river system of Southeast Asia - Bangladesh, Nepal, Myanmar and Indian
state of Assam. These fishes are found in the rapidly flowing permanent hill-streams without
tidal influence.
There are about 12 species under the Genus worldwide. In Bangladesh, only three species
have been documented (Box 1.) They have been found only in a few hill-streams near the
Bangladesh-India border in Dinajpur, Mymensingh, Sylhet and Chittagong region.
In the Red Book published in 2000, all three fishes, - Psilorhynchus balitora, P. gracilis
and P. sucatio have been described as data deficient (IUCN Bangladesh 2000). Through
surveys conducted over the last ten years by the research team of Bangladesh Agricultural
University (BAU), all three species were found in a few occasions and are maintained in the
Fish Museum and Biodiversity Center (FMBC) of the BAU. They, however, were found in a
very little number (one or two individuals) together with many other small fish in fishermen’s
net and never found in the fish markets. The biodiversity status of all three Psilorhynchus
should be considered as critically endangered (Table 9).
The Diversity of Cypriniforms throughout Bangladesh: Present Status… 159
Psilorhynchidae
Psilorhynchus
P. sucatio
P. balitora
P. gracilis
Box 1. The available species under the family - Psilorhynchidae in Bangladesh
Table 9. Biodiversity status of the fishes of the family Psilorhynchidae
Fish English name Local name IUCN Red Book
2000 status Present
status
Psilorhynchus balitora Balitora minnow Balitora DD CR
Psilorhynchus gracilis Rainbow minnow Balitora DD CR
Psilorhynchus sucatio River stone carp Titari DD CR
DD- Data deficient; CR – Critically endangered
4.2. Family Balitoridae
Members of the family are known as river loaches or hillstream loaches. The rheophilic
fishes are found in the well-oxygenated torrential and swift streams of the south and east
Asian countries, and Indo-Australian archipelago except in New Guinea. Pectoral and pelvic
fins of Balitorids are usually horizontally inserted. The fishes use the modified paired fins for
cleaning the rocks. The family includes more than 60 genera and over 600 species. In the
waters of Bangladesh, however, only 4 genera containing 9 species have been reported
(Box 2).
Balitora
Balitoridae
Acanthocobitis
A. botia
A. zonalternans
B. brucei
Nemacheilus
N. sikmaiensis
Schistura
S. beavani
S. corica
S. savona
S. dayi
S. scaturigina
Box 2. The available species under the family - Balitoridae in Bangladesh.
Mostafa A. R. Hossain and Md. Abdul Wahab 160
Table 10. Biodiversity status of the fish of the family Balitoridae
Fish English name Local name IUCN Red Book
2000 status Present
status
Acanthocobitis botia Mottled loach Bilturi DD NO
Acanthocobitis
zonalternans - - DD NO
Balitora brucei Stone loach - NE NF
Nemacheilus sikmaiensis - - DD CR
Schistura beavani Creek loach - DD NF
Schistura corica - Korica DD CR
Schistura dayi - - NE NF
Schistura savona - Savon korika NO NO
Schistura scaturigina - Dari NO EN
NO – Not threatened; VU – Vulnerable; EN – Endangered; CR – Critically endangered; DD- Data
deficient; NE – Not Evaluated; and NF – Not found.
As the distribution of Balitorids goes in Bangladesh, the fishes are only available in a few
hillstreams of Dinajpur, Mymensingh and Sylhet region. Presently, all the fishes under the
family Balitoridae are very rare in Bangladesh. IUCN Bangladesh (2000) described five
fishes as data deficient and two as not threatened. The biodiversity of the Balitora brucei and
Schistura dayi were not determined. In the BAU survey, six species have been found in
varying numbers, however, Balitora brucei, Schistura beavani and S. dayi were not found.
According to the number of occurrences and number of individuals present in each
occurrence, the present biodiversity status of the Balitorids is given in Table 10.
4.3. Family Cobitidae
Members of the family are known as true loaches. They are distributed in Eurasia and
northern part of Africa, but the diversity is nowhere greater than in Asia. Bottom dwelling
Cobitids are mostly of small size (less than 30 cm). Presently more than 200 species and
nearly 30 genera are idntified under this family. New species under the family are being
described regularly. Family Cobitidae in Bangladesh is represented by 5 genera and 12
species. Most of the fishes are inhibiting the hillstreams of Dinajpur, Mymensingh and
Sylhet. A few of the members are also available in rivers, swamps and ditches throughout the
country.
Among the 12 Cobitids, the biodiversity status of 3 were not evaluated by the IUCN
Bangladesh (2000), 3 fishes described as data deficient, 2 as endangered and remaining four
as not threatened. Among the twelve fishes, the BAU survey found 11 except
Neoeucirrhichthys maydelli (Table 11). The BAU survey agrees with the biodiversity status
of four Cobitids - Lepidocephalichthys annandalei, L. guntea, Pangio oblonga and
Somileptus gongota as described by the IUCN Bangladesh (2000) as not threatened (NO).
Although Bengal loach Botia dario was described as endangered by IUCN, the BAU survey
found the fishes regularly in large quantities without noticing any decreasing trend in its
biodiversity from most of the areas of Bangladesh. Therefore, the biodiversity status of the
The Diversity of Cypriniforms throughout Bangladesh: Present Status… 161
fish should be changed to the category of not threatened (NO). Remaining three Botia sp. and
Pangio pangia are described as critically endangered (CR), and Lepidocephalichthys
berdmorei, L. irrorata as endangered (EN) based on the survey findings.
Cobitidae
N. maydelli
Pangio
P. oblonga
P. pangia
S. gongota
Lepidocephalichthys
L. guntea
L. annandalei
L. irrorata
L. berdmorei
B. dario
B. dayi
B. lohachata
B. rostrata
Neoeucirrhichthys Botia
Somileptus
Box 3. The available species under the family - Cobitidae in Bangladesh
Table 11. Biodiversity status of the fish of the family Cobitidae
Fish English name Local name IUCN
Red
Book
2000
status
Present
status
Botia dario Bengal loach Bou EN NO
Botia dayi Hora loach Rani DD CR
Botia lohachata Reticulate loach Rani EN CR
Botia rostrata Gangetic loach Rani NE CR
Lepidocephalichthys annandalei Annandale loach Gutum NO NO
Lepidocephalichthys berdmorei Burmese loach Puiya DD EN
Lepidocephalichthys guntea Guntea loach Gutum NO NO
Lepidocephalichthys irrorata Loktak loach Puiya NE EN
Neoeucirrhichthys maydelli Goalpara loach
- DD NF
Pangio oblonga Java loach Panga NO NO
Pangio pangia - Panga NE CR
Somileptus gongota Gongota loach Cheng gutum NO NO
NO – Not threatened; VU – Vulnerable; EN – Endangered; CR – Critically endangered; DD- Data
deficient; NE – Not Evaluated; and NF – Not found.
Mostafa A. R. Hossain and Md. Abdul Wahab 162
4.4. Family Cyprinidae
Cyprinidae is the largest family of freshwater fish in the world with about 220 genera
containing over 2,400 species. The members are known as carps, barbs, loaches and
minnows. Goldfish, rasboras, danios are also included in the family. These fishes have soft
finrays without true spines. In some members, however, the last unbranched ray is hardened
and forms a stiff spine-like structure, and in a few species, the last anal fin ray is also
hardened. Fishes have toothless jaw but strong pharyngeal teeth. The Cyprinids are egg-layers
and most fishes do not guard their eggs, only a very few species build nests and/or guard the
eggs.
This important family of primarily freshwater fishes is widely distributed in Asia, Africa
(excluding Madagasker), Europe and North America. The family is very dominant in most
areas within its distribution and is of considerable economic importance in many Asian
countries. This large family has been divided into various subfamilies. Sixty three cyprinid
species under four subfamilies Leuciscinae, Rasborinae, Cyprininae and Garrinae are found in
Bangladesh waters (Box 4).
There are five species available in Bangladesh belong to the subfamily Leuciscinae. The
leuciscine minnows could be differentiated from the other Cyprinids by the possessions of a
sharply keeled abdominal rim and presence of highly irregular scale pattern on the dorsal
side. The 5 species are placed under 2 genera Securicula (1 species) and Salmostoma (4
species). According to the status given by the IUCN, 3 species are not threatened, one data
deficient and one not evaluated. In the BAU survey, all five species were found. Based on the
survey findings, the biodiversity status of thee leuciscine - Securicula gora, Salmostoma
bacaila and S. phulo remains unchanged, ie., not threatened as described by IUCN
Bangladesh (2000), S. acinaces is vulnerable and S. sardinella is critically endangered
(Table 12).
Subfamily Rasborinae has 9 genera containing 21 species in Bangladesh. In the BAU
survey all except two rasborine - Raiamas guttatus and Devario aequipinnatus were found.
The genus Esomus has 2 species- E. danricus and E. lineatus. E. danricus is abundantly
available throughout the country (not threatened). E. lineatus, however, is rarely found and
the diversity is rapidly decreasing (critically endangered). The two Chela species - Chela
cachius and C. laubuca should now be considered as endangered. The 2 species of
Aspidoparia was described as data deficient by the IUCN. Both the species were found in the
BAU survey and the present status of two fish is endangered. According to the BAU survey,
the biodiversity status of Begala elonga, four Barilius sp. Raiamas bola and Danio dangila
are critically endangered. The biodiversity status of two Rasbora sp., two Barilius sp., and
Devario devario should be considered as endangered and Danio rerio as vulnerable.
There are 11 genera containing 34 species under the subfamily Cyprninae found in
Bangladesh. Among the 34 species, the BAU survey did not find 6 species - Osteochilus
hasseltii, Labeo angra, L. fimbriatus, L. dero, L. nandina and Neolissochilus hexagonolepis.
The survey found 14 fishes regularly in large quantities without any decreasing trend in their
biodiversity over the years from most of the areas of their distribution (not threatened).
Although Puntius sarana was described by IUCN as critically endangered, the stable stocks
of the species in a number of rivers and floodplain were found and the fish has been
successfully bred in the laboratory. P. sarana should be described as vulnerable. According to
The Diversity of Cypriniforms throughout Bangladesh: Present Status… 163
the findings of the survey the number of endangered and critically endangered fishes under
the subfamily Cyprninae is 3 and 10, respectively (Table 12).
The outstanding identifying character of the Subfamily Garrinae is the absence of a
groove between the upper lip and snout, the upper lip is being coalescent with the skin of
snout. The pectoral and pelvic fins are horizontally placed. It has two genera containing three
species in Bangladesh. In our survey we did not find Garra annandalei. The present
biodiversity status of the two Garrinae is endangered.
Leuciscinae Rasborinae Cyprininae Garrinae
Salmostoma Securicula
S. gora S. acinaces
S. phulo
S. bacaila
Crossocheilus
C. latius
G. gotyla
G. annandalei
Esomus Chela Aspidoparia
Bengala Rasbora Barilius
E. danricus
E. lineatus
C. cachius
C. laubuca
A. jaya
A. morar
B. elanga R. rasbora
R. daniconius
B. shacra
B. tielo
B. vagra
B. barna B. barila B. bendelisis
Raiamas Danio
R. bola
D. devario
D. rerio
D. aequipinnatus
D. dangila
Chagunius Osetobrama Amblypharyngodon
A. mola
A. microlepis
O. cotio cotio C. chagunio
Osteochilus
Cirrhinus
C. mrigala
L. gonius L. nandina L. calbasu
L. boggut L. rohita L. angra
L. pangusia L. bata L. boga
Labeo dero L. dyocheilus
Catla
P. sarana
P. chola
P. guganio
P. conchonius P. ticto P. phutunio
P. sophore P. terio P. gelius
C. catla
T
.
tor
T. putitora
Devario
S. sardinella
L. fimbriatus
N
. hexa
g
onole
p
is
R. guttatus
P. puntio
Oreichthys O. cosuatis
C. reba
Puntius
O. hasseltii
Neolissochilus
Garra
Labeo
Tor
Cyprinidae
Box 4. The available species under the family - Cyprinidae in Bangladesh.
Mostafa A. R. Hossain and Md. Abdul Wahab 164
Table 12. Biodiversity status of the fish of the family Cyprinidae
Fish English name Local name IUCN Red Book
2000 status Present
status
Securicula gora Ghora chela NO NO
Salmostoma acinaces Silver minnow Chela DD VU
Salmostoma bacaila Large minnow Katari NO NO
Salmostoma phulo Finescale minnow Ful chela NO NO
Salmostoma
sardinella Sardinella
minnow Chela NE CR
Esomus danricus Flying barb Darkina DD NO
Esomus lineatus Striped barb Darkina NE CR
Chela cachius Glass barb Chhep chela DD EN
Chela laubuca Glass barb Chhep chela EN EN
Aspidoparia jaya Joya Joya DD EN
Aspidoparia morar - Morari DD EN
Begala elonga Megarasbora Elong EN CR
Rasbora daniconius Slender rasbora Darkina DD EN
Rasbora rasbora Gangetic rasbora Darkina EN EN
Barilius barila - Barali DD EN
Barilius barna - Koksa DD CR
Barilius bendelisis - Joiya EN EN
Barilius shacra - Koksa DD CR
Barilius tileo - Pathorchata DD CR
Barilius vagra - Koksa EN CR
Raiamas bola Trout barb Bhol EN CR
Raiamas guttatus Burmese trout Bhol NE NF
Devario
aequipinnatus Giant danio - EN NF
Devario devario Sind danio Debari NO EN
Danio dangila - Nipati DD CR
Danio rerio Zebra danio Anju NO VU
Amblypharyngodon
microlepis Indian carplet Mola NO NO
Amblypharyngodon
mola Mola carplet Mola NO NO
Osteobrama cotio
cotio - Dhela EN EN
Chagunius chagunio Chaguni Chaguni DD CR
Osteochilus hasseltii Silver
sharkminnow - DD NF
Labeo angra - Angrot NO NF
Labeo bata Bata Bata EN NO
Labeo boga - Bhangon CR CR
Labeo boggut Labeo boggut - DD CR
The Diversity of Cypriniforms throughout Bangladesh: Present Status… 165
Table 12. (Continued)
Fish English name Local name IUCN Red Book
2000 status Present
status
Labeo calbasu Orange-fin labeo Kalibaus EN NO
Labeo dyocheilus - Ghora machh DD CR
Labeo fimbriatus Fringed-lipped
carp - NE NF
Labeo gonius Kuria labeo Sada gonia EN NO
Labeo nandina - Nandil CR NF
Labeo pangusia - Baitka CR CR
Labeo rohita Rohu Rui NO NO
Labeo dero Kalabans Kursa NO NF
Neolissochilus
hexagonolepis Copper mahseer - DD NF
Cirrhinus mrigala Mrigal Mrigal NO NO
Cirrhinus reba Reba Raek VU NO
Catla catla Catla Katla NO NO
Puntius chola Swamp barb Chalapunti NO NO
Puntius conchonius Rosy barb Kanchonpunti NO NO
Puntius gelius Dwarf barb Gilipunti DD EN
Puntius guganio Glass barb Molapunti NO CR
Puntius phutunio Spottedsail barb Phutanipunti NO EN
Puntius puntio Puntio barb Punti DD CR
Puntius sarana Olive barb Sarpunti CR VU
Puntius sophore Pool barb Bhadipunti NO NO
Puntius terio Onespot barb Teripunti NO NO
Puntius ticto Ticto barb Titpunti VU NO
Oreichthys cosuatis - Kosuati NO CR
Tor putitora Putitor mahseer Mohashol NE CR
Tor tor Mahseer Mohashol CR CR
Crossocheilus latius - Kalabata EN EN
Garra annandalei Sucker head Ghorpoiya DD NF
Garra gotyla gotyla Sucker head Ghorpoiya DD EN
NO – Not threatened; VU – Vulnerable; EN – Endangered; CR – Critically endangered; DD- Data
deficient; NE – Not Evaluated; and NF – Not found.
Among the 87 Cyprinifoms reported in Bangladesh, the BAU survey observed 74 over
the last ten years. The biodiversity status of many of these have now changed from that listed
in the IUCN Red Book published in 2000. The changed biodiversity status proposed here is
based primarily on the study of specimens maintained in the Fish Museum and Biodiversity
Center (FMBC) of the BAU and through surveys conducted over the last ten years. Figure 5
shows that although the percentage of not threatened and vulnerable Cypriniform remained
mostly unchanged over the last ten years, the percentage of critically endangered fish
increased almost five times. Many Cypriniforms described as data deficient by IUCN were
found in the BAU survey. The biodiversity of these fishes, however, remains under severe
threat and most are described as either endangered or critically endangered.
Mostafa A. R. Hossain and Abdul Wahab 166
CR
6% EN
16%
VU
2%
NO
29%
DD
36%
NE
11%
a
CR
32%
NO
30%
NF
15%
EN
20%
VU
3%
b
Figure 5. Comparison of percent of Cypriniform fishes under different categories – a. IUCN
Bangladesh 2000 and b. Present status NO – Not threatened; VU – Vulnerable; EN – Endangered; CR –
Critically endangered; DD- Data deficient; NE – Not Evaluated; and NF – Not found.
5. THE MAJOR CAUSES OF LOSS OF FISH BIODIVERSITY
In the past the major source of fish production in Bangladesh was the inland open water
capture fisheries. During 1960s, it contributed about 90% of the country’s total fish
production. Rapid growth of population coupled with lack of proper management policy,
however, created increasing pressure on fish resources and aquatic environment. Due to over
exploitation of fish including use of harmful fishing gears and system (fishing by
dewatering), degradation and loss of fish habitats, obstruction of fish migration routes by
construction of embankment and water control structures mainly to increase agriculture
production and road communication, siltation of water bodies by natural process, introduction
of a number of alien invasive fish species and water pollution by industry, and agrochemicals,
the natural inland fish stocks have declined significantly and fish biodiversity and poor
fishers’ livelihood have been affected seriously (Ali 1997).
The Diversity of Cypriniforms throughout Bangladesh: Present Status… 167
Fish stocks in the rivers and floodplains are declining for a variety of reasons. Most of the
indigenous fish are migratory and rely on seasonal flooding for spawning cues and access to
larval rearing habitat (floodplain). Almost all dams and embankment interfere directly with
the successful completion of the fish migration (breeding and feeding). Agriculture (excessive
removal of surface water and extraction of groundwater for irrigation), pollution (domestic
and industrial), and unregulated discharge of untreated industrial and farm effluents, habitat
destruction also have significant impact, as does the regular overflooding and lack of flooding
rain in the last few decades. Introduced species (primarily tilapia, Chinese carp and Thai
pangas) are significant contributors to aquaculture production, but also threaten the
biodiversity of indigenous fishes. In past, stocking of rivers and floodplain is carried out with
both indigenous and introduced species by government and through different projects. The
effectiveness of stocking activities has generally not been well assessed. Furthermore, the
impacts of aquaculture (both commercial and small scale) have not been accurately assessed
in this country.
Most of the literal and floodplains areas are cultivated with rice and other crops,
providing multiple annual harvests. Thus, government policy has always prioritized cereal
food production. Consequently, most development initiatives in the country have focused on
crop cultivation, rather than biological management of the rich floodplain system for fish
production, ignoring the needs of poorer people for access to renewable protein sources.
Capture fisheries in inland waters which are based on natural productivity generally have
reached the level of overexploitation. The inland open water fisheries, where the floodplains
assume an important position in the livelihoods and nutrition of the rural poor have now been
under serious threat of resource depletion due to various man-made and natural causes. The
majority of the waters of this type have been depleted to an alarming state and warrant urgent
interventions for conservation and sustenance. Ecosystem integrity has often been
destabilized and aquatic systems now fail to support decent levels of aquatic life. As a result
the livelihoods of fishers and rural Bangladeshis, previously supported by the inland open
waters, are seriously compromised (Coates 1995). Some rivers and floodplains have been
modified to a level where they are only recognized as narrow ditches and paddy fields.
During 1960s, the inland capture fisheries contributed about 90% of the country’s total
fish production. Production from inland capture fisheries has declined significantly over the
years and in 2005-06 it accounted only about 40% (Figure 6a). During 1960s, production
from inland capture fisheries was almost 20 times higher compared to the then aquaculture
production of the country (Figure 6b). However, aquaculture production both in fresh water
and brackish water has significantly increased during the last two and a half decades with
development of technology. Due to the rapid increase of aquaculture production and sharp
decrease of capture fishery production, in 2007-08, the aquaculture contributed almost
equally (about 40 %) as inland capture fisheries in total fish production of the country (FRSS-
DoF 2008). There has been a qualitative degradation of fish catch in terms of valued species
which included cypriniforms like Indian major carps and olive barb. The Indian major carps
contributed 67% of the total stock in 1967 in Sylhet-Mymensingh haor basin that rapidly
declined to 50% in 1973 and only 4% in 1984 (Tsai and Ali 1987).
Mostafa A. R. Hossain and Md. Abdul Wahab 168
0
20
40
60
80
100
60-61 65-66 70-71 75-76 80-81 85-86 90-91 95-96 00-01 05-06
% contribution of inland capture i
n
total production
a
0
4
8
12
16
20
60-61 65-66 70-71 75-76 80-81 85-86 90-91 95-96 00-01 05-06
Inland capture : aquaculture ratio
b
Source: Ali et al. (2009).
Figure 6. Trend of fish production in Bangladesh 1960-2006, a. Contribution of inland capture (%) in
total fish production, and b. Inland capture to aquaculture ratios
5.1. Effects of Usage of Pesticides and Chemicals
Every year, there are thousands of tons of different pesticides (insecticides, herbicides,
piscicide, miticides, fungicides, weedicides etc.) used around the globe that enter into aquatic
systems from direct application and indirectly through terrestrial runoff or wind-borne drift.
Pesticide affects the aquatic ecosystem by interrupting the aquatic food chain of open water
fish species resulting loss of natural diversity (Parveen and Faisal 2002).
The Bangladesh Pesticides Rule clearly states that "no person shall import, manufacture,
formulate, repack, sale, hold in stock, or in any other manner advertise any brand of
pesticides which has not been registered." The naive and illiterate farmers are, however,
convinced by glib sales talk at promotional camps, and through incentive schemes, to buy
new unregistered formulations that promise to protect crops against pest attacks and disease.
Suppliers continue to sell many chemicals banned by the government. The increased reliance
on pesticides in rice and other crop production has, in some areas, proved to be unsuitable and
unsustainable due to pesticide-induced outbreaks of insect pests, development of pesticide
The Diversity of Cypriniforms throughout Bangladesh: Present Status… 169
resistant pests, rising cost of pesticide use and the negative effects of pesticide use on human
health and the environment (Pingali and Gerpacio 1997).
The inundated floodplains of Bangladesh during monsoon are the seasonal habitat of the
many indigenous fish. The residual effects of pesticides applied to these floodplains for
agricultural purpose before monsoon lead to the fish mass mortality. Besides fish killing,
there are also many other chronic effects of pesticides on fish including changes in their
reproductive system, metabolism, growth patterns, food availability and population size and
numbers (Rohar and Crumrine 2005). Lower abundance of phytoplankton and, consequently,
lower abundance of zooplankton are observed as a result of pesticide use in the waterbodies.
The application of a pesticide might kill all individuals and it can be substantial perturbation
to the ecosystem.
The pesticides affect the aquatic biodiversity in two ways depending on the intensity:
sublethal (chronic) effect and lethal (acute) effect. The sublethal concentrations of pesticides
can alter a wide range of individual traits including changes in neurotransmitters, hormones,
immune response, reproduction, physiology, morphology and behaviour including reduced
foraging and changes in swimming ability, predator detection, learning and social interactions
(Weis et al. 2001). At relatively high concentrations, pesticides become lethal and kill the
organisms immediately. However, pesticides that are sublethal for short exposure can also be
lethal to aquatic organisms when they are exposed for longer durations (chronic exposure).
The indiscriminate use of insecticides and pesticides in the crop fields by the farmers is
one of the major causes of disappearance of many fish from the natural waters in Bangladesh
High yielding varieties (HYV) of rice have replaced the indigenous ones resulting in
substantial increase in insecticides and pesticides use and causing total disappearance of fish
from many monsoon fed water bodies (Mazid 2002). Prolonged misuse of pesticides and
fertilizers over the years has also halted the development of inland fisheries and aquaculture
(Abdullah et al. 1997).
10,000
15,000
20,000
25,000
30,000
1996 1997 1998 1999 2000 2001 2002 2003 2004 2005
Pesticide used (metric ton)
Source: Bangladesh Crop Protection Association, Aziz (2005) and www.moa.gov.bd/statistics/
Table4.15CP.htm.
Figure 7. Trend in pesticide use in Bangladesh during 1996-2005.
Mostafa A. R. Hossain and Md. Abdul Wahab 170
Pesticide use in Bangladesh got started from mid 1950s and gained momentum in late
1960s with the introduction of green revolution through the use of HYV rice in the country
(Rahman 2004). A total of 94 pesticides, with 299 trade names of different groups and
formulations have been registered for use in the crop fields. In 1999, the total use of
pesticides was about 14,340 mt (active ingredient 2,462 mt) (Banglapedia 2004). In pesticide
sector, farmers have been receiving extension services and considerable subsidies from the
government over the years (Hossain 1988). As a result of the expansive policy and to
minimize the increasing demand of staple crops, pesticide use in Bangladesh has been more
than double since 1996, rising from 11,700 mt to 25,466 mt in 2005 (Figure 6). Among the
different pesticides, more than 60% are insecticides and used mainly in the paddy field.
Table 13. The exotic fishes introduced into the freshwaters of Bangladesh and the
countries they imported from
Common name Scientific Name Source Year of
introduction
Siamese gourami Trichogaster pectoralis Singapore 1952
Goldfish Carassius auratus Pakistan 1953
Tilapia Oreochromis mossambicus Thailand 1954
Guppy Poecilia reticulata Thailand 1957
Common carp Cyprinus carpio India, Nepal 1960
Mirror carp Cyprinus carpio var specularis India, Nepal 1979
Scale carp Cyprinus carpio var communis India, Nepal 1965
Leather carp Cyprinus carpio var nudus India, Nepal -
Grass carp Ctenopharyngodon idella Hong Kong, 1966
Silver carp Hypophthalmichthys molitrix Hong Kong 1969
Nilotica Oreochromis niloticus Thailand 1974
Thai sarpunti Barbonymus gonionotus Thailand 1977
Bighead carp Hypophthalmichthys nobilis Nepal 1981
Black carp Mylopharyngodon piceus China 1983
African magur Clarias gariepinus Thailand 1990
GIFT (genetically
improved farmed tilapia) Oreochromis niloticus Philippines 1994
Genetically improved
scale carp Cyprinus carpio var communis Vietnam 1995
Thai pangas Pangasius hypophthalmus Thailand 1990
Giant pangas Pangasius gigus Thailand -
Mosquito fish Gambusia affinis India -
Sucker mouth catfish Hypostomus plecostomus Hong Kong,
Singapore -
Red piranha Pygocentrus nattereri Hong Kong,
Singapore 2003
Pirapatinga Piaractus brachypomus Hong Kong,
Singapore 2003
Modified from Rahman (2005).
The Diversity of Cypriniforms throughout Bangladesh: Present Status… 171
Table 14. The negative impacts of exotic fishes on the cyprniform fishes
Exotic fish Impact
Tilapia Their prolific breeding surpasses the carrying capacity of the waterbody
leading to stunting of tilapia and a number of cypriniform SIS – mola,
dhela, anju, darkina, chela, punti etc.
Common carp Destroy pond embankments, make water turbid by stirring up mud.
Reduce the water transparency and dissolved O2 in water. Destroy the
habitat of SIS living closed to the pond dyke and loaches in the bottom.
Grass carp High feeding competition with many herbivorous cypriniforms.
Silver carp Strong feeding and habitat competition with cypriniform – catla in both
captive condition and in the wild
Thai sarpunti Compete with local sarpunti for foods and space
African magur Predation and voracity of this catfish is legendary, predate on almost all
small fishes including most cypriniforms
Thai pangas Natural diet is finfish, crustacean and insects, periphyton and benthos.
This predatory fish is the major cause of disappearance of SIS from the
pond system
Mosquito fish They live in the littoral zone of the waterbody and compete with small
cypriniforms for food and habitat
Suckermouth
catfish One of the dangerous catfish, now found in the floodplain allover the
country, feeds on small crustaceans and cypriniforms like small loaches
and freshwater eel
Red piranha One of the most dangerous and aggressive species of piranha, feeds on
insects, worms and small and large fish. The cultured fish in the pond
system and escapees in the wild actively predate on the indigenous
fishes including many cyprinifomrs
Pirapatinga The natural diet is terrestrial plants, fruits, insects and crustaceans,
however, in captivity where the natural food is scarce the pirapatinga
predate on small cypriniforms. The fish has strong, human like teeth
used to crush food items.
In the inland open waters of Bangladesh, mass mortality of fish by pesticides mainly
occurs due to the use of pesticides in improper doses and use of banned chemicals. The most
commonly used pesticide in the crop field is organochlorine which is highly toxic to fish and
other aquatic organism. In sub-lethal doses, organochlorine affects the reproductive
physiology of fish and other aquatic fauna. A few drops of endrin can kill all fish in a pond.
Hossain and Halder (1996) reported that the main cause of disappearance of the fish from the
inland open water of Bangladesh was the use of excessive and banned pesticide and 100%
fish mortality occurred within 96 hours of the application of a number of pesticides following
even recommended dose for the crop. Lethal dose and even at sub lethal dosage of chemical
residues of pesticides largely attributed to cropland runoff contaminants killed fish as well as
other aquatic organisms (Parveen and Faisal 2002).
Mostafa A. R. Hossain and Md. Abdul Wahab 172
5.2. Introduction of Exotic Fish
Allover the world the exotic species have been recognized as an agent of the loss of
indigenous biodiversity. Alteration of species and ecosystem caused by exotic invasive
animals and plants influence the functioning and overall health of the affected ecosystems
(Ameen 1999).
As a country of rivers and wetlands, Bangladesh is very rich in fish diversity. Even then,
over the last six decades a total of 23 fishes have been introduced (Table 13). The invasive
species rapidly spread over the wetlands as biological explosives during the rainy seasons.
Most of the introduced species were meant only for captive cultivation in closed pond
systems but nobody succeeded to maintain the fish in captivity. During monsoon and/or flood
the escapees easily found their ways to the rivers and floodplains throughout the country. This
posed one of the major threats to the biodiversity of many indigenous fishes in this country.
Several introduced species are highly carnivorous and predatory and eat almost
everything including the small indigenous species of fish (SIS - which grow to a maximum
length of 5- 25 - Felts et al. 1996). Sixty fishes out of 87 cyprinids are considered as SIS.
Several exotic species also compete with the SIS and gradually occupy their niches. The
ecological, economic and biodiversity consequences of the introductions of exotic fish species
have never been taken into consideration. It is very unfortunate that the long-term, and even
short-term adverse effects were not considered while introducing the invasive species in
Bangladesh. The excessive fecundity and growth rate of these species created pressure on the
carrying capacity of the habitat, and the ecosystem balance itself by reducing the indigenous
species diversity and population. Some of the negative impacts of exotic species on
Cypriniforms are given in Table 14.
6. THE CONSERVATION MEASURES
The government of Bangladesh and a number of non government organizations (NGOs)
have taken a number of regulatory and development interventions for sustainable
management of the natural fisheries. In order to reverse the loosing trend and ensure
sustainability of fish biodiversity and production from inland open waters various measures
for protection, conservation and management of fisheries resources have been adopted time to
time. Among the measures are the implementation of Fish Protection and Conservation Act
1950 and related rules including new fisheries management policy (licensing the fishing
rights directly to the true fishers), community based fisheries management (CBFM),
establishment of fish sanctuary in the strategic points of the rivers and floodplains, fish stock
enhancement through releasing fish seed in seasonal floodplains, and fish habitat
improvement through excavation of link canals (between rivers and floodplains) and beels.
The Fish Act 1950 provides regulations for: (i) restriction on capture size of some fish for
a specific period, (ii) restriction on catch of any species for specific time or season, (iii)
closure of fishing in any water body for any stipulated time period, (iv) restriction of fishing
by dewatering or any other destructive method, (v) restriction on the use of any kind of gear
and mesh size of net, and (vi) restriction on placing fixed engine in a water course, which
may restrict fish migration.
The Diversity of Cypriniforms throughout Bangladesh: Present Status… 173
Implementation of fisheries regulations has proved to be very difficult in this country due
to institutional weakness of implementing authorities and the socio-economic conditions of
the fishers. However, the Fish Act 1950 element – ‘closure of fishing in specific area for
specific period’ as may be termed as ‘fish sanctuary’ is easier than applying other regulations
of the Fish Act. Sanctuary has been tested and found as a powerful tool for protection and
conservation of fish stock in Bangladesh.
The dry season is the critical time for the fishes, when water levels in the rivers, canals,
beels etc. recede drastically leaving a very few refuge for the inland fishes. Fish are exposed
to greater predation and increased susceptibility to fishing pressure as the water level drops
due to water extraction for irrigation and evaporation due to persistent heat of the dry season.
Loss of surface water in the dry season results in the reduction in the brood fish stock. The
fishes become increasingly vulnerable to intensive fishing and thereby the fish stock
particularly the brood stock depletes to such a level that cannot sustain the fisheries and
gradually fish diversity and production decline. Therefore, the major issue for biodiversity
conservation is to provide sufficient dry season refuges to maintain the population at
sustainable level.
Among all measures, fish sanctuary has been apparently found most effective for fish
biodiversity conservation, when other measures are difficult to implement in the present
administrative and social contexts. With this notion, Bangladesh government has established
fish sanctuaries under different development projects following a number of management
approaches since 1960 and more intensively in last decade. The NGOs like BRAC,
CARITAS, CNRS, PROSHIKA and WorldFish Centre (CBFM project) have also been
involved in fish stock development by establishing traditional sanctuaries in beels and rivers
of Bangladesh.
In addition, a number of silted up beels, baors, dead rivers and link canals have been re-
excavated by the government under the food for work programs over the years. By 2000 a
total of about 8,300 ha water area of borrow pit, baors, dead rivers, canals and beels had been
excavated (DoF 2005). In the late 1990s the government approved a series of sectoral policies
including National Fisheries Policy (1998), National Environment Policy (1995), and
National Land Use Policy (2001) with a new emphasis on maintaining and protecting the
moribund inland waterbodies. Under the National Fisheries Policy, government has
formulated strategies for inland capture fisheries and emphasized on fisher community
participation in fisheries management, along with fish sanctuaries as a key management tool
(DoF 2005).
6.1. Fish Sanctuaries
The massive siltation has threatened the existence of most of the inland waterbodies –
rivers, floodplains, beels, haors and baors. Many waterbodies once the blessings for
Bangladesh providing fishing, communication and irrigation facilities are now drying up at an
alarming rate. Most of the waterbodies are becoming empty of fish. The causes of reduced
abundance of fish are over-fishing, reduced flooding, siltation, agricultural and industrial
pollution etc. These activities have severely affected the indigenous fish diversity of the
country. The complete drying up in many parts of the river and other waterbodies is a
Mostafa A. R. Hossain and Md. Abdul Wahab 174
common scenario during lean season, which is detrimental to fish populations. Where
perennial waterbodies have been transformed to seasonal waters due to several manmade and
natural factors, establishing a fish sanctuary (refuges where fish are protected during the dry
season) can help to restore the fish habitat and fish diversity. The establishment of fish
sanctuaries in the deeper parts of the waterbodies where fish reside during dry season and
grow and attain maturity for spawning in the next monsoon– is particularly very important. At
the onset of early monsoon rains, these fish disperse on the rivers and adjacent floodplains for
breeding and feeding.
Following the provision of the Fish Act 1950, Govt. declared closed season for fishing of
certain species or for all species of fish in specified water bodies under normal fisheries
management programme and under different development schemes/projects of DoF. In 1952
Govt. prohibited catching of cypriniforms - rui, catla, mrigal, kalibaus and gonia of any size
in rivers and canals for different time period between mid March to 31 July every year except
for pisciculture purposes. Under the Development and Management Scheme of Department of
Fisheries (DoF), 23 sanctuaries were established in different floodplains during 1960-1965.
Upon having good results of the established sanctuaries, 25 more sanctuaries were established
under the same scheme of DoF during 1965-70. Afterwards 10 more sanctuaries were
established in 1987 under the Integrated Fisheries Development Project of DoF.
Most of the fish sanctuaries now focus on the need of involvement of fisher community
and local govt. in the management system, long tenure of lease period and also strong
monitoring and supervision. Besides, to safeguard of the fishers interest, the Govt. policy now
is to establish sanctuary in part of the floodplain and the remaining part is open for fishing by
the local fishers. Based on this idea, under different development projects, government has
established a number of sanctuaries involving the fisher communities with support of NGOs.
In a government declared fish sanctuary, catching/killing of fishes is prohibited by law and
order of competent authority for all the times to come or for a specified period mainly with
objective of protecting/conserving the fish.
A total of 463 permanent fish sanctuaries covering an area of 1,745 ha have been
established in 98,405 ha water bodies by 2007 (Table 15). A number of the sanctuaries have
been closed after the projects ended. Management has deteriorated in many sanctuaries due to
the conflict of interests among the stakeholders, lack of funding and lack of coordination
among the organizations.
Fish sanctuary in Bangladesh was proved to be an important and efficient tool for
management in protection and conservation of fishes and other aquatic organisms (Ali et al.
2009). Since mid 80s, concept of the involvement/participation of local fisher community in
setting up and managing sanctuaries has been the government policy. However, a major
problem in managing sanctuaries in public water bodies is the policy conflict between the
government ministries. Although the national fisheries policy envisages establishing fish
sanctuaries, there is no clear guideline for establishment and management of fish sanctuaries.
To make the fish sanctuaries more effective, the following stages should be followed -
mitigation of all the conflicts among the stakeholders involved, formulation of clear
guidelines of sanctuary management, selecting the strategic place and size of the sanctuary,
proper awareness building among the stakeholders, ensuring proper community organization
and full participation and continuous monitoring and impact assessment.
The Diversity of Cypriniforms throughout Bangladesh: Present Status… 175
Table 15. Fish sanctuaries established in Bangladesh by 2007
Project/ Programme Area of
water body
ha
Area of
Sanctuary ha Number of
Sanctuary
Fourth Fisheries Project 12,233 1,022 63
Community Based Fisheries Project
(CBFM-2) 9,602 93 182
Management of Aquatic Ecosystems
through Community Husbandry
Project (MACH)
785 76 65
New Fisheries Management Policy 1,698 77 21
Fisheries/ Fish Culture Development
in Beel and Chharas project 1,294 18 29
Aqua Development Project (Faridpur) 454 11 14
Patuakhali Barguna Aquaculture
Extension Project (PBAEP) 307 26 19
Fish Habitat Restoration Project 3,890 73 45
Fisheries Development in Jabai Beel
project 75 4 4
Sustainable Environment
Management Programme (SEMP-17) 50 17 12
Community Based Wetland
Management Project(CBWM- 4) 17 4 7
Kaptai Lake 68,000 324 2
Total 98,405 1,745 463
Modified from Ali et al. (2009).
6.2. Fish Breeding, Domestication and Gene Banking
As more fish species of Bangladesh become threatened, there is tremendous need to
preserve the disappearing genetic material as well as to conserve the existing gene pools. The
ideal strategy for conservation of threatened and endangered fish species is through
restoration of the native habitat of the species (in situ approach). Unfortunately, most habitat
damages are irrevocable and where remediation is possible it is costly and requires a great
deal of time, as the restoration process is slow. One alternative is to maintain ex situ
conservation (outside the natural environment) as live populations or in a cryopreserved
sperm bank (Pullin et al. 1991).
Domestication of wild fishes in most cases benefits both the farmer and the environment.
Investments in domestication have to pay off; therefore, researches should take into account
the biodiversity and production scenario and overall socioeconomic and environmental
outcome at a broader scale. In Bangladesh, to date about 22 fish species have been
domesticated and their breeding and rearing protocols have been developed. Around 50% of
the domesticated fishes are cypriniforms and now under nation-wide aquaculture (Table 16).
Though there is high possibility of working with reduced gene pool, it is optimistically
believed that the biodiversity of the domesticated fish are well-preserved.
Mostafa A. R. Hossain and Md. Abdul Wahab 176
Table 16. The domesticated indigenous fishes of Bangladesh
Order Fish Culture status
Cypriniformes Catla catla Country-wide commercial
Labeo rohita Country-wide commercial
Labeo gonius Country-wide commercial
Labeo bata Country-wide commercial
Labeo calbasu Small scale, sporadic
Cirrhinus mrigala Country-wide commercial
Cirrhinus reba Small scale, sporadic
Tor putitora Breeding protocol developed
Puntius sarana Small scale, sporadic
Lepidocephalichthys guntea Breeding protocol developed
Botia dario Breeding protocol developed
Osteoglossiformes Chitala chitala Small scale, sporadic
Siluriformes Ompok bimaculatus Small scale, sporadic
Ompok pabda Small scale, sporadic
Mystus vittatus Small scale, sporadic
Mystus gulio Breeding protocol developed
Clarias batrachus Small scale, sporadic
Heteropneustes fossilis Small scale, sporadic
Synbranchiformes Mastacembelus armatus Breeding protocol developed
Macrognathus aculeatus Breeding protocol developed
Perciformes Anabas testudineus Breeding protocol developed
Colisa fasciata Breeding protocol developed
Recently there has been expanded development of cryogenic sperm banks (preservation
of fish sperm in liquid N2 at -196 oC) for fish in Europe and North America. These sperm
banks are more cost effective than maintaining live gene banks which require wide space,
maintenance and high costs. Cryogenic gene banking avoids the risk of genetic contamination
and requires little space and minimal facilities.
Fish sperm cryopreservation assists conservation of fish biodiversity through gene banks
of endangered species, and assists aquaculture by providing flexibility in spawning of females
and selective breeding through synchronizing artificial reproduction, efficient utilization of
semen, and maintaining the genetic variability of broodstocks (Lahnsteiner 2004). The
technique also ensures preservation of genetic materials of the genetically superior wild fish
populations and the gene transfer between wild and hatchery stocks (Tiersch et al. 1998).
The sperm cryopreservation protocol for different fish species seems variable and
species-specific. Although fish are the main protein source in Bangladesh and other countries
in the sub-continent, and the fish biodiversity and production from open water are declining,
little attention has been paid to cryopreservation of fish sperm. In Bangladesh, research on
fish sperm cryopreservtion was started in early 2004. The studies have focused on
aquacultured or commercial species and so far none of the threatened species have been
considered (Table 17).
The Diversity of Cypriniforms throughout Bangladesh: Present Status… 177
Table 17. Cryopreservation of sperm of some fish species in Bangladesh
Fish group Fish
Indigenous - cypriniform Catla catla
Cirrhinus mrigala
Labeo rohita
Labeo calbasu
Puntius sarana
Indigenous - others Ompok bimaculatus
Mastacembelus armatus
Channa striatus
Rita rita
Exotic fishes Cyprinus carpio
Hypophthalmichthys molitrix
Hypophthalmichthys nobilis
Barbonymus gonionotus
Oreochromis niloticus
Genetic stock conservation for wild and domesticated fishes is very important, as the
genetic diversity of every species develops through a long evolutionary process over millions
of years. Cryogenic techniques can assist in the conservation of biodiversity, to bring back the
threatened species to natural environment with restocking programmes, as well as in
improving aquaculture production. Cryogenic sperm banks for more fish need to be
established as means of germplasm conservation in Bangladesh.
7. CONCLUSION
There is a crying need to adjust the existing laws and legislation of the country for
integrated resource management to save the fisheries resources. Although much of the
damage to the habitat and biodiversity of the inland water of Bangladesh over recent decades
is likely to be irreversible, there is still time to act. From now on, Bangladesh government, the
NGOs and national and international bodies should foster a social and technical environment
in which the enormous richness of the fisheries resources can stabilize and eventually rebuild
so as to continue to feed people of today and tomorrow. Poverty in fishing communities
should be reduced in part by ensuring a stable supply of fish, something can only be achieved
through improved knowledge, integration of fisheries and freshwater management, and
greater public involvement. In case of fishing closure in areas or for certain time, the fishers
should be provided with alternative income generating activities, credit with low interest and
other sustainable means. Creating public awareness of the importance of maintenance of fish
diversity in Bangladesh is extremely necessary and should be the first priority for a lasting
change. Sustenance of fish diversity can only be achieved with public support. Bangladeshi
fishers, fish farmers, traders, processors, and general people as a whole need - to understand
the issues, to be involved in the formulation of management plans and to benefit from the
whole process. A key step in building fisheries co-management and fish biodiversity
Mostafa A. R. Hossain and Md. Abdul Wahab 178
conservation with community participation is to bring all the various stakeholders in a
common front with a view to sharing resource and knowledge, creating an environment for
meaningful discussion on cross-cutting themes and valuing each other.
A renewable resource like fish, when under intense exploitation, needs a management
regime as it is not inexhaustible. Therefore, management measures should be applied in such
a way that young fish are protected to grow before capture and enough are left as breeding
stock for future generations. The management measures should include – regulate fishing
intensity at sustainable level, control gear selectivity, gear type and size of fish, closed season,
prohibition of destructive fishing, closed fish sanctuary, and allocation of resources to
different types of fisheries.
For sustainable and well-protected fish diversity for present and for future, the country
should go for -
Rational use of inorganic fertilizers and pesticides, and proper management of
industrial effluents,
Maintenance of minimum water depth (at least 1 m) during water extractions from
critical waterbodies,
Regulation of selective fishing gears, mesh sizes, and fishing by dewatering,
Establishment of more fish sanctuaries and natural beel nurseries in strategic points,
Stock enhancement programmes,
Establishment of community-based organizations (CBO) among the fishers,
Zero tolerance to new exotic fish introduction, and
Strict application of existing fisheries rules and regulations.
This is the high time to care for the biodiversity of the most valuable Cypriniform and
other indigenous fishes – the pride, heritage and livelihood of Bangladesh before they are lost
forever. The researchers, policy makers, GOs and NGOs and national and international bodies
should come forward to conserve the fish species using both in situ and ex situ approaches.
ACKNOWLEDGEMENTS
We wish to acknowledge the research fellows and students of the Laboratory of Fish
Biodiversity and Conservation, Bangladesh Agricultural University for their sincere
cooperation and assistance in preparing this manuscript. Thanks also are given to Dr. Andy P.
Shinn, Institute of Aquaculture, University of Stirling, UK and Mr. Md. Nahiduzzaman,
Professor Md. Samsul Alam and Professor A.K.M. Nowsad Alam, Bangladesh Agricultural
University for improving the English, and helping to rewrite some portion of this manuscript.
The Diversity of Cypriniforms throughout Bangladesh: Present Status… 179
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... It is very unfortunate that the long-term, and even short-term adverse effects were not considered while introducing the invasive species in Bangladesh. The excessive fecundity and growth rate of these species created Source: Hossain and Wahab ( 2009 ) 6 Livelihood Security: Implications from Aquaculture Sectors golam.rabbani@bcas.net pressure on the carrying capacity of the habitat, and the ecosystem balance itself by reducing the indigenous species diversity and population. ...
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The idea of establishing and expanding a railway system in India offered the most vibrant excitement in colonial mind. This excitement was reflected in the thoughts of two categories of people: those who had a romantic vision of India, often diluted by ingredients of ‘civilizing mission’ and those who found India as a veritable home for capitalist initiatives. The issues of capital investment and its impact on India's macroeconomic performance have been explored to a great extent. The issue of civilizing mission has also recently been subjected to close scrutiny. However, the ‘discussions’ and debates about the above two themes have considered the idea of cultural superiority of the West and Western capitalism as omnipotent. There has been hardly any focus on how the civilizing mission or the patterns of capitalist development in relation to the railway was informed by local circumstances. The lack of appreciation of the forces within both Indian society and nature has also led to complete indifference to the impact of railways on the indigenous society and physical landscape. This article focuses on how the railway projects in India were informed by and negotiated within Indian social and ecological atmosphere. The particular focus would be on the Bengal Delta. In cultural discourse level, the railway as a tool for civilizing mission could best be explained in terms of nineteenth-century romanticism. Lord Tennyson had a vision of taking some ‘savage women’ and of raising his ‘dusky race’ in some distant parts of the world. In his project, he, however, was not handicapped by the obstacles of distance and sluggishness as the pre-railway generation of the messengers of civilizing mission had experienced.
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The endangered razorback sucker Xyrauchen texanus is endemic to the Colorado River system in western North America and is threatened with extinction because of limited recruitment. To assist in management and recovery efforts, we developed methods for the cryopreservation of sperm, evaluated the influence of various factors on motility of thawed sperm, and examined the effect on fertilization of cooling rate and the addition of caffeine. Sperm samples cryopreserved with 10% methanol (MeOH) had significantly higher postthaw motility than did samples preserved with 5% or 20% MeOH or with 5% or 10% dimethyl sulfoxide, N,N-dimethylacetamide, glycerol, propylene glycol, or ethylene glycol. Sperm samples cryopreserved in 0.5-mL and 2.5-mL straws had significantly higher postthaw motility than did samples cryopreserved in 0.25-mL straws. Exposure to 10% MeOH for up to 30 min did not significantly influence sperm motility before freezing or after thawing. Cooling rate (-21°C/min or -91°C/min) did not significantly influence sperm motility. Samples thawed in a water bath at 20°C, 30°C, or 40°C had significantly higher motility than did samples thawed on the laboratory bench (19°C). Refrigerated sperm had significantly higher motility after the addition of 0.005 M caffeine; however, caffeine did not increase the motility of thawed sperm. Fertilization percentage was 41 ± 31% for the egg quality control treatments (fresh sperm) in the freezing rate study. The freezing rate of -91°C/min yielded 66% fertilization relative to the control (actual value, 27 ± 26%), which was significantly higher than the 12% fertilization (actual, 5 ± 3%) yielded by the freezing rate of -21°C/min. Fertilization percentage was 25 ± 24% for the egg quality control treatments in the caffeine study. Caffeine-treated sperm yielded 60% fertilization relative to the control (actual, 15 ± 13%), which was significantly higher than the 16% fertilization (actual, 4 ± 4%) yielded by sperm without caffeine treatment.