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Pramod Kumar Pandey
Dean
College of Fisheries
Central Agricultural University
Agartala, Tripura
Introduction
India stands second in terms of fish production in the world
with a production recorded at 9.3 million tones. 60% (5.8 m T)
is contributed by inland fisheries (FAO, 2010).
Inland fisheries sector of India is not only a livelihood
provider (75% of 14.49 m fisherfolks are from the inland
sector), but a crucial source of food/ nutritional security to
millions of poor, lining the banks of its 7 m ha of inland water
area.
Rivers in India are facing multiple problems of severe
pollution, over extraction, encroachment, dams and barrages
which cut off the connectivity of the river with its associated
ecosystems, climate change, deforestation in catchment areas.
Aquatic Resources of India
India has vast and varied aquatic resources in different form






Rivers and Canals173,287 km
Ponds and Tanks2.25 mha
Lakes, Beels and Swamps- 1.3 mha
Reservoirs 2.9 mha
Brackish water 1.23 mha
Coast line 8,129 km
Riverine Resources of India
Indian river system having a combined length 29,000 km in the form of 14 major rivers (catchment > 20,000 km²)
 44 medium rivers (catchment 2000 to 20,000 km²)
 innumerable small rivers and streams.
Riverine system:
A) Himalayan river system
 Ganga river system (2225 km)
 Indus river system (combined length 4025 km)
 Brahmaputra river system
B) Peninsular river system
 East coast river system (combined length 647 km)
• Godavari river system
• Mahanadi river system
• Krishna river system
• Cauvery river system
 West coast river system
• Narmada river system
• Tapti river system
The Ganga River system
 Harbors
the richest
freshwater fish fauna of
India
 Gangetic
carps
to
mahseers and other
coldwater fishes of the
Himalayas, the hilsa,
catfishes etc.
The Ganga River System flows through 10 states in India and also in Nepal and
Bangladesh.
These rivers form one of the largest alluvial mega-fan regions of the world, and
deliver huge quantities of sediment from the Himalayas to the northern Indian plains
and to the Bay of Bengal in the Indian Ocean.
The Gangetic floodplains shape not only landforms but also complex human
cultures that attempt to stabilize themselves and adapt to the constantly changing
riverine forces.
Fish Biodiversity
27,800 fish species globally reported, about 11% are found
in Indian waters.
A total of 2225 finfish species have been reported from
India
629 from freshwater
 182 brackish water
1370 from marine ecosystem.
2934 species of crustaceans
 5000 mollusks
765 species of echinoderms
It is likely that the number of species might be more in
different ecosystems
Principal Fishery Resources of Ganga
Indian major carps
Catla catla
Labeo rohita
Cirrhinus mrigala
Labeo calbasu
Mahseer
Tor putitora
T. mosal
T. tor
N. hexagonolepis
Other carps
Labeo pangusia
L. dero
L .gonius
Cirrhinus reba
Larger catfishes
Sperata aor
S. seenghala
Silonia silondia
Wallago attu
Pangasius pangasius
Bagarius bagarius
Rita rita
Feather backs
Notopterus notopterus
Chitala chitala
Other catfishes
Clupisoma garva
Eutropiichthys vacha
Ailia coila
Ompok bimaculatus
O. Pabda
Clupeids
Hilsa ilisha
Gudusia chapra
Setipinna phasa
Freshwater prawns
Macrobrachium malcolmsoni
M. birmanicum
M. lamarei
We
are on the edge !
 Fragmented rivers with ‘no flows’








in between dams
Deteriorating water quality
Flood plain farming under threat
Fish catch and fisheries on the
decline
Riparian ecosystems losing
continuity and diversity
Flood plains cut off from flows
Flows not reaching the delta and
seas
Salinity traveling deep inland
Basins are closing
Current Problems/Vulnerabilities
•Waterlogging
•Siltation
•Erosion
•Lack of Irrigation Water
•Climate Change
•Lack of Freshwater Flow
•Lack of Appropriate
Technology
Waterlogging Risks
• Reduce scope of crop cultivation
• Mortality of fruits and plantation crops
• Affects soil health
•
•
•
•
Siltation Risks
Affect drainage system
Create water logging
Increase flood threat
Hamper water flow of canal and river
Lack of Appropriate technology Risks
•
Hamper food security
Erosion Risks
 Affect Fertility
 Decrease cultivable land area
 Migration of agricultural labor/farmers
Lack of Irrigation Water Risks
• Hamper irrigation
• Reduce crop production and yield
• Decrease cultivable land area
Lack of Freshwater Risks
 Hamper irrigation
 Reduce crop production and yield
Lack of Freshwater Flow Risks
 Salinity increased
 Washing of Land hamperred-Crop production and
yield decreased
 Unavailability of irrigation water
 Decrease cultivable land area
Climate Change Risks
 Cyclone Increase
 Embankment erosion
 Waterlogging
 Siltation
 Changing cropping pattern
 Reduce cropping intensity
 Crop biodiversity affected
Salinity Risks
 Hamper crop production and yield
 Soil degradation
 Crops extinction
 Affect homestead garden and Fodder cultivation
Major threats
Siltation
Siltation is most often caused by soil erosion or sediment spill.
Sometimes siltation is called sediment pollution, although that
is an undesirable term since it is ambiguous, and can also be
used to refer to a chemical contamination of sediments
accumulated on the bottom, or pollutants bound to sediment
particles.
Dams on the Ganga
The key problem of fisheries
today is that low level of water
in the dry-season, because of
flow regulation by dams,
barrages and hydropower
projects.
Obstruction and fragmentation
of
river
flow,
habitat
destruction,
accelerated
erosion and siltation, longdistance water diversions and
poor flow releases are the
major direct threats of damcanal systems in the Gangetic
plains.
Flow volume problems
Globally, fragmentation and flow regulation have caused the most severe
impacts through drastic alterations to riverine biota and ecology.
Low flows and fragmented connectivity of river channels lead inevitably to
fish population declines and breeding failure.
Over time, dams have probably led to genetic isolation of fish populations as
well as river dolphin / crocodile populations, destruction of fish breeding habitats
and spawning triggers and loss of valuable wild fish germplasm.
These losses are so large in their ecological value
and opportunity costs that they cannot be
recovered with artificial fish culture techniques
or hatcheries.
Different flows have different functions
 High flows - important for channel maintenance,
bird breeding, algae control, wetland flooding and
maintenance of riparian vegetation.
 Moderate flows - critical for recycling of organic
matter from river banks and for fish migration
 Low flows - necessary for fish spawning, water
quality maintenance, the use of the river by local
people, etc.
Why should a river flow from source to sea ?
 Is a river just water flowing waste to sea
 Is river an ecosystem in itself or a drain for carrying water
 Does a river have any functions or is just a conduit -evolutionary
and ecological functions
 delivering rich nutrients to the sea
 sustaining fisheries and livelihoods;
 protecting wetlands with their capacity to filter out pollutants;
 providing habitat for a rich diversity of aquatic life
 safeguarding fertile deltas;
 protecting water quality;
 maintaining salt and sediment balances;
Aggravation of pollution effects
The Ganges basin is one of the most
polluted large river basins in Asia,
especially with regard to domestic
sewage and agricultural runoff.
Poor flows reduce the dilution and selfpurification capacity of river water to
reduce concentration of pollutants and
local impacts on fishes.
Agricultural
fertilizers
(organophosphates, organochlorines,
nitrates etc.), heavy metal pollution
from industrial effluents, thermal power
plants, oil refineries, distilleries and
tanneries, and nitrogen-rich sewage,
waste-water and non-biodegradable
substances such as plastics, mercury,
radioactive compounds and hospital
wastes can cause fish kills or even
worse, lead to high levels of toxicity in
tissues.
Habitat destruction and alteration of erosiondeposition dynamics
•Soil erosion by erratic and sudden releases before floods can potentially lead to
alteration and destruction of fish breeding habitats and stock depression.
•Flow alteration also alters hydrological connectivity and sediment transport with
wetlands and confluence channels during flooding. As a result these productive
breeding habitats often become unavailable for catfishes and carps.
•These factors together become a problem for pre-settlement of fish juveniles and
recruits, which move into the main channels.
Perception of Fishers
 90% singled out “large dams and poor river flows” as
the main causes for a near-total decline in fisheries
and fish resources over the past 4 decades.
 About 90% people mentioned low water availability
and stoppage of fish migratory routes by large dams
as the main cause for fish declines.
 Almost 45% ( from eastern and northern UP, and
Bihar) singled out the Farakka barrage as the main
problem.
 Today, fisher folk from UP, Bihar and W B provide a
large proportion (20-40%) of construction and manual
labor force across India
 Others who stay behind have to take to menial jobs
such as rickshaw-pullers or servants
 Some are forced to take to crime to be able to feed
themselves and their families.
 These factors can weaken the social resilience of
production systems and create poverty, disparity and
community breakdown.
Mitigation measures
•Provide enough water, adequate natural flows in all rivers.
•Allow fish movements upriver, currently blocked by large dams
and barrages.
•STOP new dams and mindless, high-cost, destructive and
unsustainable engineering projects such as river interlinking.
•Ban on destructive practices of fishing, especially mosquitonetting, poisoning, dynamite-fishing, shooting net operation.
•Fishers are in need of government loans or credit, technical
know-how, permits and I-cards, housing, education and
displacement packages.
• Clearly define fishing use and access rights across all
rivers,
• Provide
clear
guidelines
on
multi-objective
management of fisheries amidst other economic
activities
 Urgent need to reduce the presently excessive river
pollution, especially industrial but also domestic
wastes.
 Other alternative livelihoods include working with
river management authorities, conservation agencies,
ecotourism, agriculture etc.
•Focus on community-based management of river
fisheries and help it develop in an ecologically friendly
and sustainable manner by formation of co-operative
society.
•Needs to be ensured through continued monitoring of
fishing activity and behavior, including by-catch or
hunting of species. This can also help the spread of exotic
food fishes that are rapidly invading our rivers (the
worst examples are Tilapia species, Chinese and
Common Carps, and more recently, Red-bellied Piranha
Conclusion
 Finally, the quest for sustaining fisheries in the
Ganga River basin in the long-term will require
rethinking of current dominant paradigms to
move towards ecological restoration of rivers,
their biodiversity, as well as socially just, rightsbased and equitable socio-political restoration of
traditional fisher communities and fisheries
management systems.