THE CONSERVATION ACTION PLAN THE GANGES RIVER DOLPHIN - 2010-2020 FOR National Ganga River Basin Authority Ministry of Environment & Forests
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THE CONSERVATION ACTION PLAN
FOR
THE GANGES RIVER DOLPHIN
2010-2020
National Ganga River Basin Authority
Ministry of Environment & Forests
Government of India
Prepared by R. K. Sinha, S. Behera and
B. C. Choudhary
2MINISTER’S FOREWORD
I am pleased to introduce the Conservation Action Plan for the Ganges river dolphin
(Platanista gangetica gangetica) in the Ganga river basin. The Gangetic Dolphin is one of the last
three surviving river dolphin species and we have declared it India's National Aquatic Animal.
Its conservation is crucial to the welfare of the Ganga river ecosystem.
Just as the Tiger represents the health of the forest and the Snow Leopard represents the health
of the mountainous regions, the presence of the Dolphin in a river system signals its good
health and biodiversity. This Plan has several important features that will ensure the existence
of healthy populations of the Gangetic dolphin in the Ganga river system.
First, this action plan proposes a set of detailed surveys to assess the population of the dolphin
and the threats it faces. Second, immediate actions for dolphin conservation, such as the
creation of protected areas and the restoration of degraded ecosystems, are detailed. Third,
community involvement and the mitigation of human-dolphin conflict are proposed as
methods that will ensure the long-term survival of the dolphin in the rivers of India.
This Action Plan will aid in their conservation and reduce the threats that the Ganges river
dolphin faces today. Finally, I would like to thank Dr. R. K. Sinha , Dr. S. K. Behera and Dr.
B. C. Choudhary and others who have been working on this document. I look forward to the
implementation of this Conservation Action Plan.
Regards,
Jairam Ramesh
Minister of State for Environment & Forests (Independent Charge),
Government of India
3ACKNOWLEDGEMENTS
We are indebted to Dr. Manmohan Singh, Hon’ble Prime Minister of India, Sri Nitish Kumar,
Hon’ble Chief Minister of Bihar, and Sri Jairam Ramesh, Hon’ble Minister of State for
Environment and Forests (Independent Charge), Government of India for their support in
declaring the Ganges River Dolphin as the National Aquatic Animal, and to the National
Ganga River Basin Authority, Ministry of Environment and Forests, for constituting a
Working Group for the preparation of this Conservation Action Plan for the Ganges River
Dolphin and for financial support through the same.
We are thankful to all the contributions received from the participants to the Workshop for the
formulation of this Action Plan, held at Patna on the 22 and 23 February, 2010. We are
grateful especially to Dr. Randall R. Reeves, Chairman of the Cetacean Specialist Group of
International Union for Conservation of Nature (IUCN), Sri P. R. Sinha, Director, Wildlife
Institute of India, Dehradun, Sri B. A. Khan, Chief Wildlife Warden, Government of Bihar,
and Dr. A. R. Rahmani, Director, Bombay Natural History Society for their scientific and
technical support during the Workshop and later. The participation, enthusiasm and
willingness to devote time and thought to our requests for advice and assistance are testimony
to their commitment to the Ganges River dolphin’s conservation.
We are grateful to Sri Rajiv Gauba, Joint Secretary, Ministry of Environment and Forests,
Government of India for his untiring support and encouragement for long term initiatives for
Ganges dolphins in India.
Finally, thanks to Sri Shashank Srinivasan for his contribution to the editorial process of this
document.
4Copyright
Reproduction of this publication for educational or non-commercial purposes is authorized without prior
permission from the copyright holder provided the source is fully acjnowledged.
Citation
Sinha, R. K., Behera, S. K., and Choudhary, B.C. 2010. The Conservation Action Plan for the Ganges River
Dolphin 2010-2020. Ministry of Environment and Forests, Government of India. 33 pp.
Patna University, Patna
5CONTENTS
PREAMBLE 5
CHAPTER 1:
INTRODUCTION 6
CHAPTER 2:
A SCIENTIFIC ACCOUNT OF THE SPECIES 9
CHAPTER 3:
THREATS TO THE GANGETIC DOLPHIN 12
CHAPTER 4:
STRATEGY FOR THE CONSERVATION OF THE RIVER DOLPHIN 15
CHAPTER 5:
RECOMMENDATIONS FOR THE CONSERVATION OF THE GANGES RIVER DOLPHIN 18
CHAPTER 6:
ACTIONS FOR CONSERVATION OF THE GANGES RIVER DOLPHIN 22
REFERENCES 25
TABLE:
POPULATION STATUS OF THE GANGES RIVER DOLPHIN IN THE GANGES RIVER SYSTEM 29
APPENDICES 31
6PREAMBLE Ganges River dolphin were made under the
Ganga Action Plans (GAP) I (1985) and II
(1991) through research and conservation
The Ganges River dolphin, Platanista projects. These provided baseline scientific
gangetica gangetica, is one of the most information about the species, including the
charismatic mega-fauna of the Indian fact that habitat degradation, through
subcontinent. pollution and reduced water flow, and
poaching were threatening its existence.
It is among the four obligate freshwater
dolphins found in the world with the others
being the 'bhulan' or Platanista gangetica The Prime Minister declared the Ganges
minor in the Indus River in Pakistan, the River dolphin as the National Aquatic
'baiji' or Lipotes vexillifer in the Yangtze Animal in the First Meeting of the National
River in China, and the 'boto' or Inia Ganga River Basin Authority (NGRBA) on
geoffrensis in the Amazon River. The 'baiji' the 5th of October 2009. The Ministry of
was reported to be functionally extinct in Environment and Forests (MoEF)
2006. subsequently notified the Ganges River
dolphin as the National Aquatic Animal on
The Ganges River dolphin is distributed in the 10th of May 2010 and constituted a
the Ganges-Brahmaputra-Meghna and Working Group to prepare a Conservation
Karnaphuli-Sangu river systems of India, Action Plan for the Ganges River dolphin.
Nepal and Bangladesh. The total population
is estimated to be between 2500 and 3000 This plan recommends a number of specific
individuals in its entire distribution range, conservation actions, including some related
out of which more than 80% is within Indian directly to management. The challenge is to
territory. implement these plans and ensure the long-
term survival of the dolphin in the rivers of
This species has been included in Schedule I India.
of the Indian Wildlife (Protection) Act 1972,
in Appendix I of the Convention on
International Trade in Endangered Species
(CITES), in Appendix II of the Convention
on Migratory Species (CMS) and categorised
as Endangered on the International Union Note:
for the Conservation of Nature's (IUCN) This Action Plan for the Conservation
of the Ganges River dolphin has been
Red List.
prepared under the auspices of the
The Ganges River dolphin is extensively National Ganga River Basin Authority
mentioned in India’s mythological and and thus these recommendations
historical literature. However, it was William concern dolphin populations only in
Roxburgh, the then Superintendent of the the Ganga and its tributaries.
Calcutta Botanical Garden, who wrote the Conservation recommendations for the
first scientific paper on this species in 1801. Brahmaputra River and its tributaries
will be covered in a subsequent
John Anderson published a report on its
biology, including a distribution map, in publication.
1879 after which there is no record of further
scientific work on this animal for the next
one hundred years.
The first efforts in the 20th century to
document the status and threats faced by the
7Chapter 1 Construction of embankments as flood
control measures in eastern Uttar Pradesh,
INTRODUCTION Bihar and West Bengal has disrupted the
connections between the river and its flood
There are three recognised species of river plains and wetlands. About 3500kms of
dolphins, which inhabit rivers and estuaries embankment were constructed in Bihar post-
in Asia and South America, and all are Independence resulting in the increase of the
among the most endangered cetaceans on flood prone area from 2.5 million ha to
Earth. In fact, one species, the 'baiji' or almost 7 million ha. Similarly 1811kms and
Chinese river dolphin, was declared 1184kms of embankment were constructed
functionally extinct in 2006 (Turvey et al in Uttar Pradesh and West Bengal
2007; Hopkin 2007). The remaining species respectively. Embankments interrupt access
are the Amazon River dolphin, the Ganges to the spawning habitat for floodplain-
River dolphin and the Indus River dolphin. dependent fish and eliminate eddy-counter
Although several marine dolphin species are currents where the Ganges River dolphins
commonly found in rivers quite far upstream, spend much of their time. Dredging and the
river dolphins are morphologically and removal of stones, sand, and woody debris
phylogenetically distinct from marine also compromise the ecological integrity of
dolphins and most are restricted to the riverine environment, especially in small
freshwater ecosystems. Because rivers are tributaries. Increasing pollution in the river
more vulnerable to degradation than the may adversely affect dolphin health and their
ocean, river dolphins are in worse shape than bioaccumulation may have serious
their seafaring cousins. consequences.
The Ganges River dolphin is endemic to the DISTRIBUTION
Indian sub-continent and has a fairly
extensive distribution range. It is found in Historical distribution
the Ganges-Brahmaputra-Meghna and
Karnaphuli-Sangu river systems of India and “The water-hog is in all Hindustan rivers”
Bangladesh, while a few individuals may said Babur in the Babur Nama (circa 1500
survive in the Karnali, and the Sapta Kosi AD). Probably by “all Hindustan rivers”,
Rivers in Nepal. While there is no Babur was talking about the rivers of North
meaningful estimate of range-wise India, where he had traveled widely. Cuvier
abundance, approximately 2500-3000 (1836) claimed that the ‘susu’ ascended the
Ganges River dolphins are assumed to Ganges in great numbers to the limit of their
survive across their entire range. Due to a navigability. Anderson (1879) recorded its
continued decline in its population, the distribution in the Ganges over an area
IUCN changed its status from ‘Vulnerable’ to comprised between 770E and 890E; in the
‘Endangered’ in 1996. Brahmaputra it occurred throughout the
main river, as far eastwards and upstream as
Numerous factors exist for this decline; the 950E by 27030'N. He also reported that even
deliberate killing of Ganges River dolphins in the month of May, when the Ganges was
for oil and meat still occurs. The demand for very low, dolphins were seen as far up the
these products means that there is little Yamuna as Delhi. He also emphasised that
incentive for fishermen to reduce the by- the upstream range of this dolphin was only
catch or to release dolphins that are still alive limited by insufficiency of water and by rocky
when they are found entangled in nets. The barriers. The Ganges River dolphin occurred
construction of more than 50 dams and in the entire length of the Ganga and
barrages within the Ganges River dolphin’s Brahmaputra, and all their tributaries from
historic range has drastically altered its the delta at the Bay of Bengal till the
habitat and fragmented the meta-population. Himalayan foothills, where only rocky
8barriers, high velocities or shallow water
limited its distribution. •It is a unique charismatic mega-fauna.
Current Status and Distribution •The species has recently been declared the
‘National Aquatic Animal’ by the
The Ganges River dolphin ranges into most Government of India, and is part of our
of the large tributaries in the Ganges Basin: national heritage.
the Ramganga, Yamuna, Gomti, Ghaghara,
Rapti, Son, Gandak and Kosi besides the Lessons learned from the Yangtze River
main channel of the Ganga. In the dolphin
Brahmaputra valley it ranges into the major
tributaries such as the Tista, Adadhar, The Yangtze River dolphin, Lipotes vexillifer,
Champamat, Manas, Bhareli, Subhansiri, has been declared functionally extinct due to
Dihang, Dibang, Lohit, Disang, Dikho and uncontrolled development, illegal fishing
Kulsi rivers. Downstream it ranges through activities and intense vessel traffic in the river
the larger tributaries between the Hugh and (Turvey et al., 2007). Both the Ganges River
Meghna rivers, as far as the tidal limits at the and Yangtze River dolphins have similar
mouth of the Ganges. They are also reported environmental requirements. The Indus
from the Fenny, Karnaphuli, and Sangu River dolphin has a low population estimated
rivers to the southeast of the mouths of the to be around 1600-1700 individuals (WWF-
Ganges (Rice 1998). Pakistan 2010). Therefore, rapid
conservation actions are required before the
Ganges dolphins have been extirpated from Ganges River dolphin population declines
portions of their upstream range in Nepal irreversibly. Freshwater dolphins in Asia are
and India, and populations have been among the world’s most endangered
fragmented and reduced in numbers where mammals and there is an urgent need to
they still occur (Table 1; Sinha et al., 2000). establish conservation priorities based on
scientifically credible abundance estimates
Importance of the species (Perrin and Brownell, 1989; Smith and
Reeves, 2000a; IWC 2001; Smith and
The Ganges dolphin is an indicator species Jefferson, 2002).
for the river ecosystem and is at the apex of
the food chain. It is an endemic and rare The Ganges River dolphin is a Flagship
aquatic mammal found only in the Indian Species for river conservation
subcontinent and is part of our natural
aquatic heritage. Developing a It is clear that there is enormous public
comprehensive program to conserve river support for ensuring the maintenance and
dolphins in Ganga is required for the protection of the Ganges River dolphins. As
following reasons: a flagship species, its conservation requires
greater efforts along the lines of that
•India is the last stronghold with extant provided to the tiger and the elephant. Other
populations in the Ganges-Brahmaputra endangered river species such as the softshell
River Systems. The species is in peril in turtle (Aspideretes gangeticus ), gharial
Nepal and Bangladesh. (Gavialis gangeticus ) and smooth-coated
otters (Lutra perspicillata) will also benefit
•It is an excellent indicator of riverine from conservation actions that benefit the
ecosystem health. Ganges River dolphin.
•As a signatory to numerous international
conventions, India must fulfill its treaty
obligations to aid in the conservation of this
species.
9HABITAT water in monsoon and it is thus assumed that
the water temperature and turbidity are not
Water levels in the Ganga are seasonal in significant factors in determining the
nature. Peak flows occur between July and distribution of this species.
September when the river is fed by monsoon
run-off and Himalayan melt-water, while Habitat Fragmentation
leanest flow occurs from February to March.
The flow in the Ganga and its tributaries is The complex geomorphology of freshwater
regulated, and the natural flow regime has and estuarine systems tends to concentrate
been disrupted, by the construction of dams the distribution of cetaceans in counter-
and barrages. While there were occasional currents associated with confluences,
reports of dolphin sightings in some of the meanders and mid-channel islands (Hua et
smaller tributaries of the Ganga during the al., 1989; Smith, 1993; Smith et al., 1997,
1980s, it is now likely that dolphins have 1998). The Ganges River dolphin population
been completely extirpated from these rivers was fragmented by construction of the dams
due to insufficient and inconsistent water and barrages on the main stem of the Ganga
supplies. The large-scale diversion of river and its tributaries (Smith et al., 2000).
water for irrigation in the dry season causes Barrages are low, gated diversion dams
water flow to diminish especially between comprised of a series of gates used to control
Haridwar and Allahabad. the elevation of an upstream ‘head pond’.
Barrages also restrict the movement of river
Habitat preference dolphins and other aquatic mega-fauna,
thereby separating them into subpopulations.
Although the Ganges dolphin is fluviatile in Reeves et al., (1991) questioned the degree to
habit, it may also be found in brackish water, which dolphin subpopulations are isolated,
though it never enters the sea. It is generally suggesting that individuals may occasionally
assumed that salinity defines the downstream move downstream through barrages.
limits of its distribution, while physical
barriers and low prey densities at high Dolphins in the main channel of the Ganga
elevations define the upstream limits. were split into two subpopulations in 1975
Dolphins are abundant in the long stretches when the Farakka Barrage was
of deep water in association with shallow commissioned. The Lower Ganga Barrage at
water meanderings, confluences and mid- Narora (1966) and the Middle Ganga
channel sand bars. Barrage at Bijnor (1984) further fragmented
the Ganga main stem population into four
The primary habitats preferred by the subpopulations. Dolphins have now been
Ganges River dolphins are characterised by extirpated above the Middle Ganga Barrage
an eddy-counter current system in the main at Bijnor. Today they occur in three
river flow caused by a point bar formed from subpopulations bounded by the Bijnor,
sediments and deposits, a convergent stream Narora and Farakka Barrages (Fig.1).
branch, or by an upstream meander. They are
also found below sand bars and bridges Previous dolphin surveys
where eddies are formed.
Abundance monitoring of the dolphin
Being a mammal, the Ganges River dolphin population has been conducted since the
can survive a wide range of temperature early 1990s using direct visual counts from
fluctuations. It can tolerate temperatures as vessels through continuous surveys, surveys in
low as 50C in the River Karnali in the winter discrete segments or point counts from the
in Nepal, and as high as 350C in the summer river bank (Smith, 1993; Smith et al., 1994;
in the plains of Uttar Pradesh and Bihar. Sinha et al., 2000). Methods were
They have also been found in highly turbid insufficiently detailed and hence it was not
10easy to evaluate bias, estimate precision, or
reliably detect trends from the data. In
addition, different workers used different
methods, precluding direct comparison of
counts in different stretches of different
rivers.
There has been considerable international
concern regarding the endangered status of
the Ganges River dolphin. The IUCN
Cetacean Specialist Group and other
researchers have emphasised the importance
of establishing conservation priorities based
on scientifically credible abundance estimates
(Perrin and Brownell, 1989, Smith and
Reeves, 2000a, IWC, 2001, Smith and
Jefferson, 2002).
CONSERVATION STATUS
This species has been included in Schedule I
of the Indian Wildlife (Protection) Act 1972,
in Appendix I of the Convention on
International Trade in Endangered Species
(CITES), in Appendix II of the Convention
on Migratory Species (CMS) and categorised
as Endangered on the International Union
for the Conservation of Nature's (IUCN)
Red List.
11Chapter 2 the mouth. The species does not have
crystalline eye lens rendering it effectively
A SCIENTIFIC ACCOUNT OF THE blind, although it may still be able to detect
SPECIES the intensity and direction of light.
Navigation and hunting are carried out using
Taxonomy echo-location. The body is a deep brown
colour, stocky in the middle and attenuating
Though the names of William Roxburgh and to a narrow tail stalk behind the dorsal fin.
Heinrich Julius Lebeck are associated with The dorsal fin is a very low triangular hump
the first description of the Gangetic dolphin located two-thirds of the body length from
in 1801, priority for the description goes to the anterior end. The broad flippers have a
Dr. Roxburgh who named it Delphinus crenellated margin, with visible hand and
gangetica (Pilleri 1978). In 1828 Rene Lesson arm bones. The flippers and flukes are thin
adopted a genus based on the Bengali name and large in relation to the body size.
‘Susuk’ and described the species as Susu
platanista. However, Johann Wagler adapted Body size is about 2m - 2.2m in males and
Platanista as a genus in 1830 and from then 2.4m - 2.6m in females. At the time of birth
onwards it is known as Platanista gangetica. they measure 70cm - 90 cm and weigh
between 4 kg to 7.5 kg. While adults usually
The Indus and Ganges populations were weigh between 70 kg and 90 kg, an adult
long regarded as identical. However, Pilleri pregnant female (2.5 m) caught at Araria in
and Gihr (1971) divided them into two north-eastern Bihar in February 1993
species based on differences in skull weighed 114 kg. Similarly an adult female
structure, but Kasuya (1972) reduced the two (2.4 m) killed in the Ganga at Patna on the
taxa to subspecies of a single species. This is 29th of April 2010 weighed 97 kg.
supported by the results of Yang and Zhou
(1999), who found that there was little Primitive characters
difference between the cytochrome-b
sequences of the Ganges and Indus river Platanista gangetica gangetica bears some very
dolphins. There was probably sporadic primitive characters not known in other
exchange between the Indus and Ganges cetaceans, such as the presence of a caecum at
River dolphin populations by head-stream the junction of the small and large intestines.
capture on the low Indo-Gangetic plains The position of the testis is more dorsal than
between the Sutlej (Indus) and Yamuna that in other marine cetaceans and
(Ganges) rivers (Rice, 1998). Thus one subcutaneous muscle is present between two
species is recognised in the genus Platanista ; layers of blubber (Sinha et. al. 2010).
the Ganges River dolphins are currently
Platanista gangetica gangetica and the Indus Behaviour
River dolphins are Platanista gangetica minor.
Ganges River dolphins swim and vocalise
Physical description constantly. Due to the turbid nature of the
Ganges, the underwater activities of Ganges
The Ganges River dolphins have a long, dolphins in the wild are difficult to observe.
pointed snout that is characteristic of all river Their short surfacing time is also a major
dolphins. Both the upper and lower jaw sets constraint for behavioural studies. A recent
of long sharp teeth are visible even when the study recorded six types of surfacing patterns,
mouth is closed. While the snout is long and which were dependent on age-class and off-
widens at the tip, the female’s snout is shore distance of the individual (Sinha et al.
generally longer than that of the male and 2010a).
may curve upwards and to one side. The eyes
are extremely small openings slightly above
12Ganges River dolphins exhibit greater invertebrates (Sinha et al., 1993), and
preference for the surface than other river possibly turtles and birds. A list of prey
dolphins; even when swimming, which they species documented for the Ganges dolphins
do on their sides, they occasionally keep their is presented in Table 2. They exhibit active
beaks out of water. Newborn calves foraging behaviour in the morning (0700
frequently leap completely out of the water. hrs- 1000 hrs) and after noon (1500 hrs -
1700 hrs). The dolphins have been observed
Group behaviour chasing and preying upon surface dwelling
fish species, such as Rhinomugil corsula. On
The Ganges River dolphin is not usually some occasions it was noticed that they drive
considered to be gregarious. In one of the fishes to a particular area for community
few quantitative studies of group size, it was feeding.
observed that 90% of the groups and 80.4%
of the total dolphins observed during the dry Migration and Dispersal
season in the Meghna and Jamuna Rivers of
Bangladesh were solitary individuals. While The marked seasonal changes in the dolphin
the calves accompany mothers, adults are distribution and density over much of its
normally found alone or in small groups. range are due, at least in large part, to
However, other investigators reported groups fluctuations in water levels. During the dry
of as many as 25 to 30 dolphins at the season from October to April, many dolphins
confluence of the Ganga and Gandak at leave the tributaries of the Ganga and
Patna. Brahmaputra systems and congregate in the
main channels, only to return to the
Reproduction and Life History tributaries the following monsoon. Dolphins
were seen 100kms upstream in the River Son
Though the breeding season of the Gangetic in the flood season in the early 1990s,
dolphin extends from January to June, newly returning to the main stem of the Ganga
born calves can be seen even in other months. after the floods abated in October. They may
While mating usually takes place between become isolated in pools and river branches
March and June, it has been observed even in during the dry season (Reeves and Brownell,
July. Only a single baby is born after a 1989). One dolphin, which had entered a
gestation period of about 9 months. At the deep pool in River Damodar from the
time of birth the neonate is about 70 cm and Hooghly river, was rescued in January 2001
weighs about 4 kg - 5 kg. The mother and after it stayed behind even after the end of
calf remain together for about one year. The the flood season.
male attains sexual maturity at an age of
about 10 years when they reach a length of The Ganges River dolphins even disperse in
1.7 meters while the females are known to the main channel of the Ganga in search of
attain sexual maturity at 10 or less years prey. Observations in Nepal show that they
(Kasuya 1972) when they are around 2m long move in and out of tributaries of the
(Harison 1972). During the surveys, Gandaki, Koshi, and Karnali systems during
newborn calves were sighted throughout the high water seasons, probably spending low-
distribution range by various surveys, which water seasons in deep pools of the tributaries.
indicates that the river habitat is conducive In the main rivers, a decrease in abundance
for dolphin breeding in spite of various biotic during the summer would confirm a seasonal
pressures. pattern of migration (Shreshtha, 1989).
Food and feeding
Ganges River dolphins are catholic feeders
and feed on several species of fishes,
13Relatively high densities of dolphins are
found at sites where rivers join or just
downstream of shallow stretches, in areas
where the current is relatively weak, off the
mouths of irrigation canals, and near villages
and ferry routes. In the Indus, about 40%-
45% of the dolphin population is found at
junctions of tributaries with the main river
stem, at least during the dry season,
presumably being attracted to these areas by
concentrations of prey (Reeves and Brownell,
1989).
The population above the Kaptai dam in the
Karnaphuli River in Bangladesh disappeared
over a period of 6 or 7 years after the
construction of the dam. Similarly, dolphin
population disappeared from the main stem of
the Ganges, above the Middle Ganga Barrage at
Bijnor (about 100kms downstream Haridwar)
after 12 years of its construction. Dolphins in
Nepal are almost extinct in Mahakali, Narayani
and Sapta Kosi due to construction of barrages
at their heads at India-Nepal border.
14Chapter 3 proximity with them, in these regions.
Accidental killing in fishing nets, as well as
THREATS TO THE GANGETIC direct killing by the fishermen to reduce
DOLPHIN competition, affects dolphin populations.
HUMAN – DOLPHIN CONFLICT Use of dolphin products
Poaching The fishermen and other riparian people in
many areas have traditionally been using
In its entire distribution range, and especially dolphin oil for burning and as a liniment
in Bihar, the species is facing threats to its (Anderson 1879). Some people regularly eat
existence from poaching. Deliberate killing the meat and in Bangladesh pregnant women
of 'susus', especially harpooning, is believed consume the dolphin oil (Smith et al. 1998).
to have declined in most areas but some Currently the dolphin oil is used as fish bait
individuals are still taken each year. Their oil in Bihar and Assam for catching two
and meat is used as liniment, as an economically important fish, Eutropiichthys
aphrodisiac and as bait for catfish. A few vacha and Clupisoma garua (Sinha 2002).
cases of poaching are recorded in the middle Demand for these products creates an
Ganges in Bihar (Sinha et al., 2000), in the incentive for poaching and a disincentive to
Kalni-Kushiyara River of Bangladesh, and in dolphin conservation. Appendix B details the
the upper reaches of the Brahmaputra River use of dolphin oil as bait.
in Assam, India (Mohan et al. 1997). With
very low population of the species in rivers, HABITAT DEGRADATION
even a few catches will have devastating
effects on long-term survival of this endemic Construction of dams and barrages
species. Appendix A details some anecdotes
of dolphin killings. Development of hydroelectric power and
irrigation in the Ganges River system has
Accidental killing prevented dolphin migration and has led to
the segregation of populations. This
Entanglement of Ganges River dolphins in fragmentation of the metapopulation has
fishing nets causes significant damage to the reduced the dolphin gene pool, leading to a
local population. Accidental killing is a severe loss of genetic diversity.
problem for Ganges River dolphins
throughout most of their range. The primary These developments have also altered the
cause is believed to be entanglement in overflow and flooding cycles of the Ganga
fishing gear such as nylon gillnets because river system, which influences the
their preferred habitat is often in the same movements and spawning of flood-plain
location as primary fishing grounds. The dependent fishes.
problem of accidental killing is expected to
worsen with increasing fishing intensity. In addition to fragmenting dolphin
Accidental killing due to collisions with populations, dams and barrages degrade
vessels has also been observed. downstream habitat and create reservoirs
with high sedimentation and altered
Dolphin - fisherman competition assemblages of fish and invertebrates (IWC,
2000).
Riverine areas of high productivity sustain a
rich and diversified fish community, which Luxuriant growth of macrophytes and
attracts dolphins as well as fishermen. excessive siltation have eliminated suitable
Dolphins face intense competition with the habitat immediately above Farakka Barrage
fishermen, and are brought into close (Sinha, 2000).
15Irrigation Sedimentation
Excess extraction of the river water for Due to loss of vegetation cover in the
irrigation has lowered water levels catchment area and in floodplains, the
throughout the species range and has increasing rates of sedimentation cause a rise
threatened suitable habitat in the Ganges. of the river bed, reducing the river's water
The long-term implications of the reduction retaining capacity. Sedimentation has a direct
of dry-season flow in the Ganges are impact on the physical and biological
catastrophic for the survival of 'susus'. characteristics of the river basin. It affects the
other river biota, including fish, reducing the
prey base of the dolphin. High altitude
The total measured flow of suspended sediment grazing, forest management, limited
in the tributaries to the Ganga River is 488 x cultivation, and road building in the
106 t/yr, while the quantity of sediment moving mountain ranges from where these rivers
in the Ganga at Farakka is 729x106 t/yr of originate are the prime factors influencing
which 328x106 t/yr is transported down the sedimentation (Wasson, 2003). The River
Hooghly River (Wasson, 2003). Ganges receives sediments from Himalayas
as well as the peninsular region
The River Kosi, one of the major tributaries of
the Ganga, carries maximum silt load in the Pollution
Ganga system with average annual suspended
load to the tune of 2774 tonnes/km2 which is The concentrations of fertilizer and pesticide
the second highest for any river of the world. residues, and industrial and domestic
The Huang River carries the highest load of effluents are very high in the Ganges River.
2804 tonnes/km2 (IUCN 1980). The effects of such pollutants may be
deleterious to dolphin populations, and
pollutant loads are expected to increase with
industrialisation and the spread of intensive
modern agricultural practices (Smith and
Reeves 2000a).
Riverine resource extraction
About 1.5 million metric tons of chemical
Dredging and development of the river fertilizers and about 21,000 tons of technical
environment has altered its nature and grade pesticides are dumped annually to the
eliminated counter currents, one of the most Ganges-Brahamaputra river system in India
preferred habitats of the dolphin. in 2002-2003. Concentrations of
Increasingly heavy river traffic in the Ganges polychlorinated biphenyls (PCBs),
and Brahmaputra may result in habitat hexachlorocyclohexane (HCH), chlordane
restriction, noise pollution, depletion of prey compounds, and hexachlorobenzene (HCB)
base and changes in feeding behavior of the in the Ganges River dolphin blubber, muscle,
'susus' in the rivers. Other sources of habitat kidney, liver and prey collected from stomach
degradation include the removal of stones, of the dolphins collected during 1993
sand (Mohan et al. 1997) and woody debris through 1996 from the River Ganges in and
(Smith, 1993). These activities threaten the around Patna, India were determined by
ecological integrity of the riverine Senthilkumar et al., (1999). The study
environment, especially in small tributaries compared the organochlorine concentrations
where suitable habitat is more confined and with values reported for samples analysed
therefore more vulnerable to local sources of during 1988 through 1992 and suggested
degradation. that the contamination by these compounds
has increased in the river. Kannan et al.,
(1997) determined concentrations of butyl-
16tin compounds in dolphins, fish, the final fate of these animals can be
invertebrates and sediments collected from monitored. Rarely can any such individuals
the Ganges in and around Patna. Total level successfully return to the main channel of the
in dolphin tissues was up to 2000 ng g-1 wet river; most of them get stranded and are
weight, which was about 5-10 times higher subsequently killed, either by the locals or
than in their diet. The bio-magnification because of the water-regulating gates in these
factor for butyl tins in river dolphin from its canals.
food was in the range of 0.2-7.5. Butyl-tin
concentrations in Ganges River organisms The depletion of prey base
were higher than those reported for several
persistent organochlorine compounds. A The sustained and heavy exploitation of
recently discovered micro-pollutant, small fishes of rivers by the wide spread use
perfluorinated compounds, was assessed in of the mosquito nets in river may affect the
tissues of the dolphin carcasses collected prey base of the Ganges River dolphin.
from the Ganges in and around Patna While the rate of renewal of this resource is
(Yeung et al., 2009). Organo-chlorine and remarkable, there is no data on prey
organo-tin concentrations in the tissues of abundance estimates and further research is
Ganges River dolphins are high enough to required to quantify this threat.
cause concern about their effects
(Kannan et al., 1993, 1994, 1997)
Possible impacts of river traffic
There have been numerous proposals to
utilise sections of the Ganga for inland water
transport. Currently, cargo steamers carry
goods from Haldia to Patna regularly,
occasionally travelling up to Varanasi. There
is heavy river traffic in and around Kolkata
and river tourism has recently been started
between Kolkata and Varanasi.
Collisions with these vessels, and the effects
of the noise they generate, are a serious
problem for dolphins. Since this species
depends upon echolocation for many of its
activities, including foraging, sonic pollution
may adversely impact their well-being. The
Ganges dolphins were seen to be avoiding
the river stretch with heavy traffic in the
River Hooghly in and around Kolkata,
preferring relatively undisturbed areas where
a lower number of mechanised vessels ply
(Sinha 1997).
Mortalities in irrigation canals
Small numbers of dolphins occasionally enter
the large irrigation canals in Uttar Pradesh.
While reports of such occurrences are
received regularly, it is only in rare cases that
17Chapter 4 habitat degradation are potentially serious
but difficult to quantify.
STRATEGY FOR THE CONSERVATION
OF GANGES RIVER DOLPHINS Concern about unsustainable exploitation
applies particularly to small cetaceans
Successful strategies to facilitate the recovery (Perrin, 1999). Ganges River dolphins are
of depleted populations, reverse trends of especially vulnerable because of their inland
population decline and habitat deterioration, freshwater distribution. A complicating
and ensure that robust populations with factor is that their small size makes the
high-quality habitat are secure will need to carcasses easy to handle, transport, process
be multifaceted, adaptable, and tailored to and conceal from management authorities.
particular local or regional conditions (Reeves Measures to regulate directed takes are not
et al., 2003). The many elements outlined easy to devise and implement, but without
below are integral to a comprehensive them, the species population is at risk.
conservation strategy for the Ganges River Among the elements needed for an effective
dolphin. management scheme are abundance
estimation and reliable demographic
The Vikramshila Gangetic Dolphin Sanctuary knowledge of how many animals are being
(VGDS) stretches for about 50 km of the Ganga removed
between Sultanganj and Kahalgaon in Bihar, and
is the only protected area designated for Ganges Developing and encouraging alternative
River dolphin. A Management Plan for the fishing techniques
VGDS was prepared in 2001 by the State
Government, but could not be implemented due Dolphin oil is used as bait to attract two
to lack of dedicated manpower and financial target fish species (Clupisoma garua and
support. Three members of the Bihar State Eutropiichthys vacha), which are then netted
Wildlife Board visited VGDS in the first week of or hooked. This use of dolphin oil and their
April 2010 to assess the current status of the body parts creates an incentive for hunting
sanctuary management plan. Activities harmful dolphins and a disincentive for fishermen to
to dolphins, such as oil fishing, and use of fishing release any that may become entangled in
nets dangerous to the dolphins, were found to be their nets.
conducted within the VGDS. In the absence of
vigorous education, monitoring and enforcement, Oil extracted from fish offal available at
dolphins are at risk in VGDS. outdoor markets has been tested and found
to be an effective substitute for dolphin oil
Ensuring that any catch or other uses of the (Sinha, 2002), and encouraging its use may
Ganges dolphin are sustainable result in a reduction of dolphin kills.
The following factors make the deliberate
exploitation of Ganges dolphin a high-risk Reducing incidental mortality through
endeavor from a conservation viewpoint: rescue and release efforts
(a) They have intrinsically low rates of
population increase; A program was initiated in Pakistan in 2000
(b) Most populations are subjected to by- to rescue Indus river dolphins that are
catch in fisheries; stranded in irrigation canals or isolated deep
(c) There is uncertainty associated with pools where they are unlikely to survive
estimates of their life history parameters, (Braulik, 2000). A similar program in Indian
absolute abundance, trends in abundance, river systems for the Ganges River dolphin
and total mortality; will contribute to its conservation.
(d) The effects of chemical and noise
pollution, reduced prey abundance, and
18Managing future dolphin-oriented tourism system should be enforced to ensure a
reduction in dolphin exposure to toxins.
Though no dolphin-oriented tourism exists
on the Ganga yet, recently introduced river Reducing the effects of water development
tourism between Kolkata and Varanasi on rivers in Ganga basin
attracted foreign tourists to watch dolphins
in the Ganga. The Ganges River dolphins need to be
considered in the assessment of impacts of
While dolphin watching is a potential water development projects. The preferred
sustainable income source for fishermen and option from a conservation perspective is to
locals, it is important to ensure that dolphin refrain from interfering with the natural flow
watching on the Ganga is conducted in a regime and to avoid constructing barriers to
manner that is respectful to the animals, local animals and sediment movement. However,
people and fellow tourists. Guidelines and socio-political conditions make it impractical
codes of conduct should be developed, to completely halt water developmental
adopted and promoted by both the tourism activities especially in the Ganga basin, so the
industry as well as by government agencies to immediate goal must be to manage such
ensure that unregulated dolphin watch activities in ways that will minimise the harm
tourism does not become a menace for the to dolphins and other aquatic species.
Ganges River dolphin.
The following principles, elucidated at a
Habitat protection and restoration 1997 IUCN workshop at Rajendrapur,
Bangladesh, on water development and
Protected areas freshwater cetaceans, may be adapted to this
context:
Existing protected areas in the Ganga and its
tributaries fall far short of what is needed. • Ganges dolphins require sufficient year-
Few protected areas capable of providing round water flow to move, forage, and
comprehensive protection to the species they carry out activities that ensure
support. reproductive success and recruitment into
A major challenge in extending the coverage breeding population.
and level of protection conferred through • Large daily fluctuations in flow should be
protected areas is to convince stakeholders avoided.
that conservation measures can benefit them • Equilibrium between sediment erosion
and thus deserve their support. and deposition is necessary to maintain
essential habitat features, which can often
While a buffer zone aids in protection, be accomplished by managing flow
animals that are relatively safe from releases according to environment
entanglement in fishing gear while inside a criteria.
reserve with strong enforcement may meet a • Access to floodplains should be preserved
gauntlet of nets as they move beyond its to ensure natural spawning and rearing
borders. habitat for fishes which are prey base of
the dolphin.
Researching and reducing environmental • Information on the pre-development
pollution ecological conditions of a river is essential
for evaluating mitigation efforts (like
While more research is needed to elucidate provision of fish ways etc.) and to
the impacts of contaminant exposure on implement future development decisions.
dolphin health, the precautionary principle • Post-development empirical studies are
demands that restrictions on the discharge of needed to monitor the operational aspects
untreated effluents into the Ganga river of projects as well as the effects on
19upstream and downstream populations of
cetaceans and their habitat.
• Cumulative and synergistic impacts of
multiple developments should be
considered in assessments of
environmental impact.
Enhancing the capacity and governance
framework for Ganges dolphin
conservation
Capacity-building refers to enhancement of
human capabilities through a combination of
education and infrastructure improvement. It
is vital that local scientists and activists be
able to provide the impetus and expertise for
dolphin conservation efforts in their own
regions.
20Chapter 5 Identified Critical Stretches
RECOMMENDATIONS FOR THE Some areas of the Ganga river system which
CONSERVATION OF THE GANGES need urgent protection measures were
identified during a workshop on the
RIVER DOLPHIN
‘Conservation of Ganges River Dolphin’
organised at Patna on 22-23 February, 2010
The Ganges River dolphins have narrow
based on inputs from the participants, which
ecological requirements and a fragmented
included most Indian dolphin researchers as
population structure. Conserving this species
well as the Chair of the IUCN Cetacean
requires coordinated efforts among agencies,
Specialist Group Dr Randall Reeves.
organisations, and communities within the
species range. Conservation issues can best be
addressed by adopting population or regional
Critical Stretches for Ganges River dolphins
level approaches for sustainable co-
management. The intention is to tailor
Uttar Pradesh
conservation strategies to the specific
Middle Ganga Barrage at Bijnore to Lower
character of highly threatened ecological
Ganga Barrage at Narora (165 km)
environments. It is important to implement
Fatatehpur to Mirzapur (150 km).
the strategies under the leadership of local
Chambal-Yamuna confluence near Etawah to
scientists, managers and community groups Ganga-Yamuna confluence at Allahabad
or stakeholders. Conservation efforts will
ultimately succeed only if embraced by the Bihar
people living in and near the animals’ Gangi-Ganga Confluence near Sinha Ghat, Ara
habitats. 20km upstream Ghaghara-Ganga confluence at
Doriganj, Chhapra) to Fatuha (confluence of
In the Ganga basin, the river dolphins have Ganga and Punpun (80 km).
declined in abundance and in the extent of Barh to Mokama to Maniharighat (Katihar)
their range. This species is competing with (210 km). This stretch includes the Vikramshila
humans for shrinking water resources. Large- Ganges Dolphin Sanctuary (60 km).
scale engineering projects that give people River Gandak from Triveni Barrage at Indo-
hope for economic development and relief Nepal border to Ganga – Gandak confluence at
from flood and famine pose dire threats to Patna (320 km)
this animal and other aquatic wildlife.
Identification of gap areas in dolphin
Anderson (1879) published a distribution
distribution range
map of the Ganges dolphin (Map I). While
much of the historical distribution range has Participants in the workshop defined ‘gap
been surveyed in the last few decades, surveys areas’ as
of many areas are yet to be conducted. The (a) areas within the known historical range of
stretches in the rivers that contain healthy the Ganges River dolphin that have not
breeding dolphin populations with long-term been surveyed systematically and
survival potential designated as ‘critical scientifically or
stretches’ need to be identified. The action (b) areas within the known historical range
Plan of the IUCN/SSC Cetacean Specialist where there is evidence indicating that
Group calls attention to the need for range- the dolphins are no longer present (i.e.
wide population assessments in support of gaps or discontinuities in dolphin
conservation efforts for obligate or true river distribution). These areas are detailed in
dolphins including the Ganges River Appendix C.
dolphins (Reeves and Leatherwood, 1994).
21Map: Historical range of the Ganges River Dolphin (Anderson, 1879)
•Develop and utilise the most appropriate
Category (a) areas identified and prioritised methodology for the population estimation
by the Working Group set up by the of dolphins.
Ministry of Environment and Forests must
be surveyed at least once a year to monitor •Develop methods for safe handling of
the population. Ganges River dolphins for scientific and
Immediate support should be provided by the rescue efforts.
Central government to researchers,
organisations and NGOs identified by the •Assessment of the habitat of the Ganges
Working Group to carry out surveys and River dolphin
researches following appropriate survey
methods in the critical stretches. •Study the movement and dispersal pattern
of the Ganges River dolphin to assess the
Identification of areas of research for long- home range and habitat utilising modern
term conservation of the Dolphin in the technologies such as satellite tracking.
River Ganga and its tributaries.
•Develop and utilise health markers in the
•Evaluate the viability of the Ganges River Ganges River dolphin to rapidly assess the
dolphin populations for long-term survival, health of an individual.
and prepare management plans for each
population. •Study bio-accumulation of toxins, and their
effects, in the Ganges River dolphins.
22•Evaluation of the genetic diversity of the injures dolphins. Use of fishing nets made up
species and development of in vitro systems of mosquito netting material (Hindi - ‘Kapda
for possible future captive breeding efforts.. jal’) should also be banned as it collects small
To increase National Awareness about the fish which serve as food for dolphins, and
Ganges River dolphin and the importance fetch very little or no income to fishermen.
of freshwater ecosystems
Since the Ganges River dolphin is a Schedule
•Identification of target groups to execute I animal under Wildlife (Protection) Act
conservation actions 1972, use of its body parts, such as tissue and
oil, is illegal. Wildlife officials should
•Designation of Brand Ambassadors for conduct frequent raids to enforce this law
awareness campaigns. and culprits must be punished under the
Wildlife (Protection) Act 1972, amended till
•Development of education and publicity date.
material.
The 5th of October should be celebrated as
•Development of a dedicated web portal for “National Indian River Dolphin Day” as on
the Ganges River dolphin this day the animal was declared as the
National Aquatic Animal of India by the
Identification of potential dolphin Prime Minister of India. This date is also
sanctuaries in the Ganga river system suitable as the week from the 2nd October to
8th October is celebrated as the Indian
Potential sites for intense dolphin ‘Wildlife Week’.
conservation should be demarcated in the
Ganga River System. Universities and research organisations
should be encouraged to develop dolphin
Provision of institutional support for the research programs
long-term survival of the Ganges River
dolphin
The establishment of Dolphin Conservation
Centers and strengthening of research
facilities available in India will aid in better
coordination among agencies responsible for
the conservation of the Ganga River dolphin.
Each state with Ganges River dolphin
populations should have a regional Dolphin
Conservation Center, with a nodal agency
responsible for its operation. It is proposed
that WWF-India in Uttar Pradesh, Morena
Center of National Chambal Sanctuary for
Madhya Pradesh, Patna University/Central
University of Bihar for Bihar and Zoological
Survey of India, Kolkata for West Bengal
should be designated as the state-specific
nodal agencies.
The use of nylon monofilament fishing
gillnets in stretch of rivers having dolphin
population should be banned, as this net
23Chapter 6 may also be considered between India, Nepal
and Bangladesh.
ACTIONS FOR CONSERVATION OF Action: Chief Wildlife Warden and MoEF
THE GANGES RIVER DOLPHIN Timeframe: Immediate
Estimated Budget: Five crore rupees
Action 1. Initiating state-wise Ganges
Dolphin Population Status Surveys and Action 3. Capacity Building for Ganges
Threat Assessment River Dolphin Conservation and
Management
Status surveys need to be conducted
simultaneously in identified critical and gap Even though the endangered river dolphins
areas at least twice a year depending upon are found in the Ganges and Brahmaputra
local conditions for a minimum period of basin, there have been few comprehensive
three consecutive years. This will help in the research programs and status surveys that
preparation of state-wise national Ganges cover the entire distribution range.
River dolphin population status reports. Universities and other institutions in India
need to be supported to develop programmes
The Chief Wildlife Wardens of each state to study Dolphins and their habitat
should consult experts to conduct surveys conditions. In addition to establishing
using standardised survey methods, detailed dedicated Centres in Ganges Basin for
in Appendix D. Local scientists should Dolphin research, identified institutions may
conduct the initial surveys, aided by experts need to be supported for conducting training
and wildlife officials. This will help in the programme for frontline protection staff as
preparation of a Ganges River Dolphin well as university researchers and teaching
Status Report staff on research methodologies. Some of
the identified organisations who could take
Action: State Chief Wildlife Wardens; up such capacity building programmes in
Timeframe: Immediate various regions are WWF-India, Wildlife
Estimated Budget: Fifty crore rupees Institute of India, and Patna
University/Central University of Bihar. The
Action 2. Setting up of Protected Areas for MoEF may also need to initiate a National
the Ganges River dolphin Dolphin Conservation Project on the lines of
Project Tiger and Project Elephant to ensure
Based on the results of the status survey and continuous funding support for capacity
identification of river stretches that support building and other conservation efforts.
breeding populations of the Ganges River
dolphin, states need to be encouraged to System has to be developed for guiding and
propose manageable Protected/Conservation adopting the research scholars by the peers
Areas under the provisions of the Wildlife for encouragement of the guided research
(Protection) Act (1972) taking local and development activities on Ganges River
stakeholders into confidence. The Chief dolphin.
Wildlife Wardens of states in the Ganges Action: MoEF
River dolphin distribution range may seek Timeframe: Immediate
the aid of professional institutions and Estimated Budget: Ten crore rupees
organisations for the development of such
proposals. Action 4. Minimising Fisheries Interface
and Incidental Capture of River Dolphins
The establishment of Trans-boundary There is a serious need to review the existing
Protected Areas for Ganges River dolphins fisheries practices, legislations and Acts. Also
24there is a need for the development of a
sustainable fishery management plan Similar ‘Dolphin Watch’ programmes in the
compatible with river dolphin existence. The Ganges river basin may be developed with
Central Inland Fisheries Research Institute, appropriate guidelines and environmental
Barrackpore or the Tata Institute of Social safeguards. Organisations such as Patna
Sciences, Mumbai could take up this as a University, Central University of Bihar,
national review with help of each of the Bhagalpur University, WWF-India and
concerned state level fishery department. Wildlife Institute of India may be entrusted
to develop and implement such model
Action: MoEF. programmes through the development of
Time: Immediate appropriate mechanisms including
Estimated Budget: Five crore rupees involvement of National and State Tourism
Organisations.
Action 5. Prevention, Mitigation and Action: MoEF, Central and State Tourism
Restoration of Impacts on Dolphin Departments.
Habitats from Developmental Projects Timeframe: Two Years
Estimated Budget: Five crore rupees
Intensive development projects proposed in
the river basins that have direct impacts on Action 7. Ensuring Critical Levels of
the dolphins and their habitat need to be Water Flow in Riverine Habitats of
identified. Environmental Impacts Dolphins
Assessments (EIAs) of such projects need to
focus and indicate the possible impact of the The survival of the Ganges River dolphin
proposed activities on dolphins. and a host of other aquatic wildlife is
dependent on riverine ecology in general and
A model Dolphin Habitat Restoration the maintenance of an optimum water flow.
Project in stretches of habitat that are Based on systematic and continued research
considered to have been degraded to a and regular monitoring with the involvement
suboptimal level may be initiated. of hydrologists and other multi-disciplinary
professionals, critical water flow and
Action: MoEF minimum depths for all river dolphin
Timeframe: Immediate habitats should be determined, and
Estimated Budget: Five crore rupees management actions should be set in place to
ensure such flow and depth.
Action 6. Community Involvement in
river dolphin Conservation and Action: MoEF.
Management Time frame: Three years
Estimated Budget: Five crore rupees
The involvement or active participation of
local stakeholders like traditional fishing Action 8. Education & Awareness
community and other riverbank communities
is essential for dolphin conservation. There With the declaration of the Ganges River
have been some initiatives in this direction dolphin as the National Aquatic Animal,
such as ‘Dolphin Mitra’ in Bihar and there is a need to educate and increase the
‘Community based Dolphin Watch awareness level of all spectrums of the society
Programme’ in Chilika Lake. Communities about the species, its habitat requirements
involved in such activities with benefit and its current threatened status.
sharing options such as ‘River Cruise’ or
‘Dolphin Watch Programme’ have helped Special attention should be given by River
popularise Dolphin Conservation & Dolphin states to set up Interpretation
Management Activities. Centers along the Ganges.
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