Mangrove booklet aw.FH10 - Zoological Survey of India

Fauna of
Ecosystems of India
Mangroves
ZOOLOGICAL SURVEY OF INDIA
Special Publication Series on the occasion of CBD CoP-11, 2012 - India

Fauna of Ecosystem of India
Mangrove Ecosystem
Compiled by
M. K. Dev Roy
C. Sivaperuman
Edited by the Director, Zoological Survey of India, Kolkata
ZOOLOGICAL SURVEY OF INDIA
Prani Vigyan Bhawan, M-Block, New Alipore, Kolkata 700 053
Phone: +91 33 2400 6893, +91 33 2498 6820
website: www.zsi.gov.in

CITATION
Dev Roy, M. K. and Sivaperuman, C. 2012, Fauna of Ecosystems of India-Mangroves:
1-11. (Published by the Director, ZSI, Kolkata)
Published : September, 2012
© Government of India
Published at the Publication Division by the Director, Zoological Survey of India,
M-Block, New Alipore, Kolkata- 700 053. Printed at Hooghly Printing Co., Ltd.,
Kolkata 700 071

Introduction
Mangroves in India account for about five per cent of the world's
mangrove vegetation covering 4,445 km2 along the coastal States
and Union Territories of the country, which is only 0.14 per cent of
the country's total geographic area (Table 1 and Fig. 1). These
mangrove habitats comprise three distinct zones namely the East
coast habitats having a coast line of about 2,700 km, facing Bay of
Bengal, the West coast habitats with a coast line of about 3,000 km,
facing Arabian sea, and Island Territories of Andaman and Nicobar
and Lakshadweep with about 1,816.6 km coastline. The long
coastlines and their mangrove vegetation have immense role in
protecting coastal biodiversity. The mangrove cover has been
categorized into, very dense mangroves, moderately dense
mangroves, and open mangroves. The very dense mangroves cover
of 1,147 km2 (25.8 % of mangrove cover), moderately dense
mangroves 1,629 km2 (36.6 %) and the open mangroves an area of
1,669 km2 (37.6 %).
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Table 1. Mangrove cover in different States and Union Territories
Area (km2 )
Sl. State / UT Very Moderately Total
No. Dense Dense Open
1. Andhra Pradesh - 15 314 329
2. Goa - 14 2 16
3. Gujarat - 195 741 936
4. Karnataka - 3 - 3
5. Kerala - 3 5 8
6. Maharashtra - 58 100 158
7. Orissa - 156 47 203
8. Tamil Nadu - 18 17 35
9. West Bengal 892 895 331 2118
10. Andaman & Nicobar 255 272 110 637
11. Daman & Diu - - 1 1
12. Pondicherry - - 1 1
Total 1147 1629 1669 4445
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Source: FSI, 2005

Geographic Distribution
Mangroves of Andhra Pradesh
Mangrove forests account for only 582 km2 , representing only about
0.9 per cent of the State's total forest area. Mangroves are found in
the estuaries of rivers, but extensive mangrove wetlands are present
only in the Godavari and Krishna deltaic regions.
Mangroves in Tamil Nadu
Mangroves in Tamil Nadu exist on the Cauvery deltaic areas.
Pichavaram has a well-developed mangrove forest dominant with
Rhizophora spp., Avicennia marina, Excoecaria agallocha, Bruguiera
cylindrica, Lumnitzera racemosa, Ceriops decandra and Aegiceras
corniculatum as the dominant flora. Mangroves also occur near
places like Vedaranyam, Kodiakarai (Point Calimere), Muthupet,
Chatram and Tuticorin.
Mangroves of Gujarat
Gujarat State, which has about 1,650 km long sea cost has mangroves
spread over an area of 911 km2 , which comes to about 20 % of the
national mangrove area. About 90 % of mangroves in Gujarat are
located around the Gulf of Kachchh while the rest of the mangroves
are found in the Gulf of Khambhat and on the South Gujarat coast.
Mangroves of Maharashtra
The Sewri Mangrove Park was declared as protected area by the
Mumbai Port Trust. This park consists of 15 acres of mangroves in
the mudflats between Sewri and Trombay.
Mangroves of Goa
A total of 1.78 km2 has been declared as Reserved Forest to protect
and conserve the mangrove forests in Goa. Mandovi River is one of
the best mangrove forests and houses most of the species found in
Goa.
Mangroves of Pondicherry
The mangroves of Pondicherry lie at latitude 11° 46'03" to 11° 53'40"
North and longitude 79° 49'45" to 79° 48'00" East and cover an area
of 1.68 km2 along the sides of Ariankuppam estuary, which opens
into the Bay of Bengal.
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Mangroves of Orissa
The mangroves of the Orissa coastal area are distributed in the
following three zones, namely, Mangroves of Mahanadi Delta,
Mangroves of the Brahmani and Baitarani Delta i.e. the Bhitarkanika
Mangrove, Mangroves of the Balasore coast. Bhitarkanika Mangrove
is also considered as the third largest mangrove zone of the country.
Mangroves of Karnataka
There are only isolated areas covered with mangroves and over the
decades these ecosystems have vanished because of denudation.
The State Forest Department now has taken up extensive cultivation
of mangroves in the estuaries of Gurupur and Nethravati Rivers.
The plantations are coming up in the River estuaries of Nethravathi,
Gurupura, Mulky, Sasihithlu, Pavanje, Thanneerbavi, Kuloor,
Panjimogaru, Adamkudru and Ullal in Mangalore.
Mangroves of Kerala
The mangroves are encountered as isolated patches and their total
area is less than 50 km2 . Mangroves are distributed in part of Kochi
Port and Research farm at Puthuvypu, Mahe to Dharmadam coastal
belt, Mallikkad, Ashram, Pathiramanal, Mangalavanam and in several
other small pockets.
Mangroves West Bengal
The Sunderbans mangroves in West Bengal are of the deltaic type
in the estuarine phase of the Ganges as well as Brahmaputra river
systems. The Sundarbans mangrove is considered the best habitat
for the Royal Bengal Tiger (Panthera tigris tigiris). As per the tiger
census 2011, it is estimated that about 270 tigers inhabit this region.
Andaman and Nicobar Islands
A total area of 966 km2 of mangrove vegetation occurs in Andaman
and Nicobar Islands. Of these, 929 km2 occur in Andaman and 37
km2 in Nicobar Islands. The mangrove vegetation of these islands
constitutes 9.4 % of the land area or 10.85 % of the total forest area.
Mangroves occurring in these islands are mostly fringing the creeks,
backwater and muddy shores.
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Faunal Diversity
Indian mangrove ecosystems are known to have a total 3066 faunal
species (Table 2). The distribution of different faunal groups in
different states is presented in Table 3. The faunal species component
is about 3 times greater than the floral component of the mangrove
ecosystem. Because mangroves occupy the intertidal zone, they
interact strongly with aquatic, inshore, upstream and terrestrial
ecosystems and in this way
mangroves help to support
a diverse flora and fauna of
marine, freshwater and
terrestrial species. The
Indian mangrove
ecosystems consist of a
wide variety of fauna and
mixture of invertebrates are
found in the mudflats
within mangrove forests.
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The most dominant groups in the mangroves are insects, mollusks,
fish and birds. The saltwater crocodile Crocodilus porosus are very
commonly seen in the mangrove ecosystem. Over 400 species of
birds have been observed including transcontinental migratory
species. Many species of mammals including Royal Bengal Tiger
(Panthera tigris tigiris), Macaca spp. and Axis axis are the most common
species in this habitat.
Table 2. Number of species of different faunal groups reported
from mangrove ecosystems of India
Sl. No. Faunal group Number of species
1. Prawns and lobsters 55
2. Crabs134
3. Insects 705
4. Mollusks 302
5. Other invertebrates740
6. Fish parasites 7
7. Fin Fish 543
8. Amphibians11
9. Reptiles82
10. Birds419
11. Mammals68
Total 3066
Kathiresan & Qasim, 2005
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Table 3. State-wise distribution of different faunal groups in mangroves of India
Number of species
Taxa West Orissa Andhra Tamil Pondi- Gujarat Maharashtra Goa Karnataka Kerala Andaman
Bengal Pradesh Nadu cherry & Nicobar Is.
Sarcomastigophora 62 - 28 - - - - - - - -
Ciliophora 31 - 71 - - - - - - - -
Apicomplexa 44 - - - - - - - - - -
Myxozoa 25 - - - - - - - - - -
Porifera 1 - - - - - 1 - - - -
Cnidaria 7 3 6 - - - 3 - - 1 -
Ctenophora 1 1 - - - - - - - - -
Platyhelminthes43 - - - - - - - - - -
Nemertinea 2 - - - - - - - - - -
Rotifera 4 - - 23 - - - - - - -
Gastrotricha - - - - - - - - - - 1
Kinorhyncha - - - - - - - - - - 1
Nemata (=Nematoda) 68 - - 40 - - - - - - 29
Acanthocephala 3 - - - - - - - - - -
Stipuncula 2 - - - - - - - - - 2
Mollusca 142 54 43 53 15 37 44 23 11 35 101
Annelida 78 36 26 98 - 6 8 7 - 31 14
Echiura 2 2 - - - - - - - - -
Sipuncula 2 1 - - - - - - - - 2
Crustacea 254 64 92 135 21 28 17 67 2 47 83
Insecta 238 44 3 142 7 - - 2 30 67 332
Archinida 114 - 5 13 - - - - - 51 3
Echninodermata 20 - - - - - 3 - - - 7
Pisces 364 48 69 217 72 65 12 24 37 132 253
Amphibia 11 5 4 3 - - - 2 - - 3
Reptilia 71 46 12 7 - 6 - 6 - 14 7
Aves234 174 125 200 24 147 121 85 32 203 53
Mammalia 47 35 23 - - 7 - 3 - 13 11
Total 1870 513 507 931 139 296 209 219 112 594 902
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Characteristic Fauna
The specialized root systems and other morphological adaptations
of mangroves form dense forests on the shore lines, creating a
secured habitat for a variety of fauna. Since the mangroves are
transition ecosystems, they give refuge to terrestrial, marine/brackish
water as well as purely intertidal organisms, making itself a rich
diverse ecosystem. The muddy or sandy sediments of the mangrove
forest are home to a variety of epibenthic, in faunal, and meiofaunal
invertebrates. The mangroves may play a special role as nursery
habitat for juveniles of fish whose adults occupy other habitats (e.g.,
coral reefs and sea grass beds), because they are surrounded by
loose sediments, the submerged mangroves roots, trunks, and
branches provide niche for epifaunal communities including bacteria,
fungi, macro algae and invertebrates.
The aerial roots, trunks, leaves and branches host other groups of
organisms. A number of crab species live among the roots, on the
trunks or even forage in the canopy. Insects, reptiles, amphibians,
birds and mammals thrive in the habitat and contribute to its unique
character. Crabs are the most conspicuous invertebrates inhabiting
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mangroves. Upper zones are inhabited by marsh crabs and closer
to shore the fiddler crabs, Uca spp., are dominant. The mud crab,
hermit crabs, prawns and shrimps are mangrove dwellers. Fiddler
crabs in particular play an important role in the cycling of nutrients
in mangrove ecosystems as they feed on detritus or micro-organisms
living on detritus.
Threatened Fauna
Total of 20 species of threatened fauna were reported from mangrove
ecosystem in India (Table 4).
Table 4. Threatened fauna of Indian mangroves
Sl. No. Family Species name
Reptiles
1. Crocodilidae Crocodilus porosus
2. Varanidae Varanus bengalensis
3. Varanidae Varanus salvator
4. Varanidae Varanus flavescens
5. Trionychidae Lissemys punctata
6. Trionychidae Trionyx gangeticus
7. Trionychidae T. hurum
8. Emydidae Batagur baska
9. Boidae Python molurus
10. Cheloniidae Lepidochelys olivacea
Birds
11. Pelecanidae Pelecanus philippensis
12. Threskiornithidae Threskiornis melanocephalus
13. Ardeidae Ardea goliath
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Threats to the Ecosystem
The threats to the mangrove ecosystem could be broadly grouped
into two: Natural and Anthropogenic. These factors may affect the
system as a whole or any one entity within the system. The natural
threats include: Climatic changes, Cyclones and Physical processes.
Diseases, deterioration, pollution, grazing, agriculture, aquaculture
and human encroachment (including reclamation), are considered
as the anthropogenic threats to the ecosystem. More than 35 per
cent of mangroves forest in the world has already been destructed.
About 50 per cent of mangroves have been cleared in countries
such as India, the Philippines, and Vietnam, while in the Americas
they are being cleared at a rate faster than tropical rainforests. The
major threats posed on the mangrove forests and their habitats are
clearing of the mangrove forests for various purposes, over
harvesting, river changes, over fishing, destruction of coral reefs,
pollution and climate change.
Conservation efforts
Many countries have promulgated laws and regulations to protect
the remaining mangrove areas and to mitigate further loss. Effective
enforcement of this legislation is, however, often hampered by a
lack of finance and human resources. Several Asian countries have
ratified the Ramsar Convention on Wetlands and have designated
mangrove areas as Ramsar sites or as National Parks, Reserves or
Wildlife Sanctuaries. In India, a legislative framework for the
conservation and management of mangroves is already in place.
The Indian Forest Act, 1927 and the Wildlife (Protection) Act, 1972
provide protection to flora and fauna. The Forest Conservation Act,
1980 states that no forest area shall be diverted for any non-forestry
purpose without prior approval of the Government of India. This
act has proved very effective in preventing diversion of mangrove
forest areas for non-forestry purposes. The Environment (Protection)
Act, 1986 also play a crucial role in the conservation and management
of mangrove ecosystems. The Government of India had set up the
National Mangrove Committee at the Ministry of Environment and
Forests in 1976 to advise the government about mangrove
conservation and development.
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Faunal group studied in the Mangrove Ecosystem by
ZSI
Andaman and Nicobar Islands: Polychaeta, Spinuculida,
Arachnida, Mollusca, Crustecea, Insecta, Echninoderms, Fishes,
Reptiles & Amphibians, Birds and Mammals
Kerala: Annelida (Polychaeta), Arachnida, Mollusca, Crustecea,
Insecta, Fishes, Reptiles & Amphibians, Birds and Mammals
West Bengal: Porifera, Cnidaria, Ctenophora, Rhyncocoela,
Aschelmithes, Chaetognatha, Bryozoa, Brachiopoda, Mollusca,
Annelida, Echiurida, Spincula, Arthropoda, Echninodermata, Fishes,
Reptiles, Amphibians, Birds and Mammals
Gujarat: Polychaeta, Mollusca, Crustecea, Echninoderms, Fishes,
Reptiles & Amphibians, Birds and Mammals
Goa: Crustacea, Mollusca, Echninoderms, Fishes, Reptiles &
Amphibians, Birds and Mammals
Tamil Nadu: Crustacea, Mollusca, Echninoderms, Fishes, Reptiles
& Amphibians, Birds and Mammals
Orissa: Porifera, Ctenophora, Bryozoa, Mollusca, Annelida,
Echiurida, Spincula, Arthropoda, Echninodermata, Fishes, Reptiles
& Amphibians, Birds and Mammals.
Andhra Pradesh: Porifera, Cnidaria, Chaetognatha, Brachiopoda,
Mollusca, Annelida, Arthropoda, Echninodermata, Fishes, Reptiles
& Amphibians, Birds and Mammals.
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