Endemic
Marsh Mongoose Herpestes palustris (Carnivora: Herpestidae)
of East Kolkata Wetlands, India: a status report
JayantaKumar Mallick
Personal Assistant
to Principal Chief Conservator of Forests, Wildlife & Biodiversity, West
Bengal Office Wildlife Wing, Directorate of Forests, Govt. of West Bengal, Bikash Bhawan, North Block, 3rd
Floor, Salt Lake City, Kolkata, West Bengal 700091, India
Email: jayantamallick2007@rediffmail.com
Date
of online publication 26 April 2009
ISSN 0974-7907
(online) | 0974-7893 (print)
Editor: C. Srinivasulu
Manuscript
details:
Ms # o1936
Received 06
February 2008
Final received
03 April 2009
Finally accepted
04 April 2009
Citation: Mallick, J.K. (2009). Endemic Marsh Mongoose Herpestes palustris(Carnivora: Herpestidae) of East Kolkata Wetlands,
India: a status report. Journal of Threatened Taxa1(4): 215-220.
Copyright: © Jayanta Kumar Mallick 2009.
Creative Commons Attribution 3.0 Unported License. JoTT allows unrestricted use of this article in any medium
for non-profit purposes, reproduction and distribution by providing adequate
credit to the authors and the source of publication.
Author Details: Jayanta Kumar Mallick Postgraduatedin 1974, joined the Wildlife Wing (Headquarters) in 1976 and has been working
as PA to PCCF, Wildlife, West Bengal, for the last 33 years. He has been
involved in all departmental publications, has participated in departmental
workshops, undertaken a number of studies, is looking after departmental data
bank and has about fifty published articles and study reports on wildlife
conservation.
Acknowledgements: Shri Sampat Singh Bist, I.F.S., ex-PCCF, Wildlife & Biodiversity, West
Bengal; Shri N.C. Bahuguna,
I.F.S., Director, Sundarban Biosphere Reserve; Shri Biswajit Roy Chowdhury, Secretary, Nature Environment & Wildlife
Society & Editor, “Environ”, Kolkata; Shri Subrata Pal Chowdhury, Technical
Assistant; Shri Indranil Mitra; Shri Somnath Chakraborty and Rabindra Nath Mistry (Wildlife Wing,
Headquarters).
Abstract:Marsh Mongoose Herpestes palustris is the only extant endemic mammal of the East
Kolkata wetlands, which has been declared a RAMSAR site in 2002. Since its
first description by the scientists of the Zoological Survey of India, the
population of this species has dwindled to an alarming state due to reclamation
of the Salt Lake City and Rajarhat expansion, as well
as from other anthropogenic causes. Recently, during a field survey only a
small population of this endangered mongoose was found in a single location.
Immediate conservation measures are required to be taken by the concerned
authorities to stop its probable extinction in the near future.
Keywords:Endemic, Marsh Mongoose, Herpestes palustris, mammal, East Kolkata wetlands, Salt
Lake, Zoological Survey of India, taxonomy, habitat, conservation, status
Abbreviations:H&B - length of head and body; Tl - length of
tail; Hf - length of hindfoot;
E - length of ear; l - length of the skull; cb - condylobasal length; mw - maxillary width; iw - least interorbital width; pow - postorbital width; pm4 - length of fourth upper
premolar; ml - mandibular length; zw- zygomatic width.
Bengali
Abstract:
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Introduction
About 11% of
Indian mammalian species are endemic, with the Western Ghats being the prime
endemic zone, followed by the Deccan Peninsula and the Andaman & Nicobar Islands. For the majority, detailed information is not
available regarding their biology and population status. Many species are known only by the type
series or even by single type specimen, and have not been recorded since their
original description.
Similarly,
endemism in wetland fauna is poorly known. Among vertebrates, one species of mammal, namely the Marsh Mongoose Herpestes palustris (reported
as a new species from Salt Lake swamp of West Bengal in 1965), 44 species of
water birds and 223 species of fish are known to be endemic to the
Indian wetlands (Alfred & Nandi 2000). Information regarding the socio-biology and present status of the
endemic Bengal or Salt Lake Marsh Mongoose is scanty given its distinctive
features, compared to the other species of the same genera sharing the same
wetland habitat, i.e. H. auropunctatus (Hodgson
1836), pointed out by the scientists of the Zoological Survey of India about 42
years ago. The land-use pattern of its habitat in the East Kolkata Wetlands
(hereinafter referred to as EKW), extending over 125km2, is agriculture
(vegetable cultivation: 4.67km2 and paddy cultivation: 48.88sq.km) and
aquaculture (47.79km2). Though
classified as wetlands, only 23.66km2 is left out of such direct human activities. The paleo-environment
of these wetlands was an extension of the Sundarbanmangroves.
Formulation and
implementation of a species-specific conservation action plan for this
dwindling endemic mongoose is urgently needed. In the year 2002 the EKW was declared formally as a conservation area of
international importance. The floral and
faunal diversity of this wetland was assessed and field surveys were conducted
to understand the present day status of the Marsh Mongoose in the wetland. Studies show that urgent conservation
measures have to be taken up for the long-term sustenance of the Marsh Mongoose
against anthropogenic threats (Sanyal 1999; Walker
& Molur 1999; Dey2007).
Materials and Methods
The Marsh
Mongoose was specifically recorded by Ghose (1965), Ghose & Chaturvedi (1973),
Schreiber et al. (1989), Agrawal et al. (1992),
Ewer (1997), Agrawal (1998), Molur& Walker (1998), Hussain (1999), Sanyal (1999), Captive Breeding Specialist Group (2000), Chattopadhyay (2001), Alfred & Chakraborty(2002), Alfred et al. (2002), Anonymous (2004), Dey(2007), and Mallick (2007). The latest field study on this species was
conducted by Nature, Environment and Wildlife Society (NEWS), Kolkata, during
2005-06.
Surveys were
conducted by NEWS in different marshy and swampy areas of the 24-Parganas
districts of lower West Bengal. Based on
interviews with the local people, fishermen and scientists of the Zoological
Survey of India (ZSI), the following wetlands of East Kolkata Wetland (included
in the RAMSAR Site) - Nalban Fishery, 4 No Bhery, Sarder Bhery,Noter Bhery, Sahebmara Bhery, Chinta Sing Bhery, Goltala Fish Project, Chokher Bhery and Gopeswar Bhery - were selected for survey.
Direct
observations were made to identify the habitats with surviving populations. Random trapping with Japanese wire traps was
carried out in all the identified habitats for six consecutive months daily
from 0630 to 1100 hr, and from 1500 to 1700 hr. Live chicks of country chickens were put inside the trap as bait. The traps were placed near the burrows of
mongoose under the camouflage of leaves of water hyacinth. Field workers observed the traps from a
distance of at least 3m with binoculars, whenever necessary. In all six Marsh Mongooses, including a
1-year old juvenile female, two adult females and three adult males, were
trapped. First, the trapped mongooses
were immobilized with chloroform, then their weight
and length were measured. Before
releasing them in the wild, they were marked with black hair dye to avoid
measuring the same individuals again, if trapped.
In addition, the
indirect method of burrow count was followed in the pre-selected occupied
niches of this species falling within their territorial range. Active burrows are noted by the closing of
the burrow mouth with clay by the mongooses in the late evening after their
entry into the nests. Active burrows
were counted the next day in the morning (0730 to 0800 hr) and their locations
marked on a map.
Study Area
EKW
(22025’-22040’N & 88020’-88035’E) is a multiple-use zone to the east of the
mega-city and includes a garbage dump (known as DhapaSquare Mile and used as such since the mid-1800s), a mosaic of vegetable
fields, a series of 300-odd fishponds connected by major and secondary canals,
rice fields, wholesale markets, a few roads, and 43 villages (with a population
of about 60,000). The ownership pattern
of the sewage-fed fisheries is - Private: 93.14%; Cooperative: 0.86% and
Government: 6%.
The EKW extends
almost equally on both sides of a dry weather flow channel, which discharges
into the Kulti Gong (the wastewater outfall), 28km to
the east of Kolkata. Geo-morphologically, these wetlands form an inter-distributorymarsh of the Hoogly-Bidyadhari (silted and choked in
1930s) system over about 76km2. Early
records show that even in the middle of the 18th century the western margin of
the Salt Lake was within 3km from the river Hooghly. The system reached peak productivity in the
middle of the 20th century but is declining due to encroachment and development
fed by a real estate boom starting from the end of the 1980s.
Conservation
Significance
The EKW
presently possess considerable biodiversity value in terms of species - 104
plants, 16 mammals, 66 aves, four crustaceans, 14
aquatic insects, 10 mollusks, 20 reptiles, four amphibians and 37 fishes (Dasgupta 1973; Chowdhury 1984; De
et al. 1989; Ghosh 1990; Nandi et al. 1993; Ghosh 1997; Chattopadhyay 2001;
Anonymous 2004).
EKW were first
protected by an order of the Calcutta High Court in 1992, prohibiting any
change in the land use. After a decade, on 19th August, 2002, these wetlands
were declared as a RAMSAR Site, the only one in West Bengal, by the RAMSAR
Convention Bureau.
Taxonomy of Herpestes palustris
The taxonomic
status of some species of mongoose is still controversial and requires further
study with fresh specimens (Alfred & Chakraborty2002). The taxonomy of the Marsh
Mongoose, like other species of the genus Herpestes,is also confused. It now belongs to
the Ichneumon or Mongoose family Herpestidae (Bonaparte 1845). It was earlier
included under Family Viverridae, the Civet Family (Ellerman & Morrison-Scott 1951; Ghose1965; Chakraborty 1989) because it was believed to be
descended from the civet-like mammals. But, herpestids are differentiated from viverrids by their rounded ears and presence of anal glands
(not perianal glands).
This species was
first described by R.K. Ghose (1965) separating it
from H. auropunctatus on the basis of skin and
skull of adult male. Agrawalet al. (1992) also maintain the same status accepting the distinguishing
characters mentioned by Ghose (1965). It is still considered a valid subspecies of Herpestes javanicus(E. Geoffroy Saint-Hilaire1818) by Wozencraft (2005). Honacki et al.
(1982) synonymized H. palustris with H. (Mangusta) auropunctatus (Hodgson 1836). Wenzel & Haltenorth(1972) and Corbet & Hill (1992) considered palustris, auropunctatus and javanicus as conspecific, whereas Ewer (1997), based on Ghose’s observation that H. palustris can emit anal scent similiar to H. urva, speculated on such a relationship to H. urva (Hodgson 1836). According to the recent (2005-06) study on the species with fresh series
of H. palustris specimens, the original (1965)
species identification of the present population in EKW has been corroborated.
Live specimens
collected
The species was
originally recorded from three districts - Howrah District, north 24-Parganas
District (Ghose 1965) and south 24-Parganas District
(Ghose & Chaturvedi1973). It is suspected to be found in
other neighbouring districts of the confirmed
locations, but there is no concrete evidence behind this. It was first discovered from the marshy and
swampy areas in the eastern part of Kolkata City on the left bank of the river
Hooghly. Twenty-seven specimens of both
sexes were collected by B. Biswas during
January-December, 1965 from Salt Lake, Bantala, Duttabad, Hederhat, and Nalban areas. During
that period, the species was fairly common in Salt Lake and other marshy areas
near Kolkata. This species was also
recorded from Botanical Garden, Shibpur on the right
bank of the Hooghly River (one specimen collected by B. Biswason 25.xi.1964), Najimganj, south of Botanical Garden
at Shibpur (Howrah) (one specimen collected by R.K. Ghose on 26.i.1965), Diamond Harbour(south 24 Pgs.) and Sukhchar, c.16 km. north of
Kolkata (north 24 Pgs.) (one specimen collected by B. Biswas on 02.viii.1964). Two more locations, viz. Patiatala and Bajbaj, were recorded by S. Chattopadhyay,
N.V.K. Ashraf and G. Christopher (Walker 1999). The study, conducted by Nature Environment
and Wildlife Society, Kolkata, in the Nalban Fishery,
4 No Bheri, Sarder Bheri, Noter Bheri,Sahebmara Bheri, Chinta Sing Bheri, Goltala Fish Project, Chokher Bheri and Gopeswar Bheri within East Kolkata Wetland through random trapping
during 2005-06, reports that the whole population of mongoose in north Salt
Lake bheri areas is constituted of Herpestes palustris as
no other sympatric species of this genus was found to be trapped during the
same study.
Species
description
There appear to
be 37 recognized species of mongoose in the world. The latest is the Bengal or Salt Lake Marsh
Mongoose, Herpestes palustris,a small cat-like carnivore. Three
more species of the genus Herpestes (Illiger 1811) occur in West Bengal. These are: Small Indian Mongoose (H. javanicus auropunctatus),Indian Grey Mongoose (H. edwardsi) and
Crab-eating Mongoose (H. urva Hodgson 1836),
of which the first two species are sympatric and the third allopatric(being inhabitants of northern Bengal and northeastern India) with Marsh
Mongoose. Moreover, H. urva is a large-sized mongoose (HBL: 45-57cm and Tl: 30-35cm) characterized by a white stripe running from
the angle of the mouth to the side of the neck. But compared to the other two
mongoose species, H. javanicus auropunctatus is common in EKW (Anonymous 2004).
On an average
(n=6 trapped individuals), an adult female marsh mongoose weighs 500-625g, length
from tip to tail 56-58cm, body length 30-32cm and tail length 25-27cm. Similarly, an adult male weighs 625-900g,
length from tip to tail 61-63cm, body length 32-36cm and tail length 26-28cm
(NEWS 2005-06). Veron et al. (2007) record
head and body length of H. auropunctatus in
the Indian subcontinent as 25-32cm. Agrawal et al. (1992) have also given the following
external measurements of the collected samples of both males and females (all
measurements in mm; range with mean in parenthesis).
Morphometrics: 15 males:
H&B 284.5-365.0(335.0); Tl 224.0-235.0(263.0); Hf 54.5-63.5(58.0); E.17.7-26.5(24.0). 4 females: H&B 303.0-315.0(309.0); Tl 240-258.0(249.0); Hf51.0-54.0(52.7); E.21.1-24.0(22.5). Cranial:14 males :
l 62.7-72.3(68.0); cb 62.3-71.5(67.1); mw
10.4-12.9(11.5); iw 10.3-12.1(11.2); pow 8.6-13.8(10.3); pm4 5.7-6.3(6.0); ml 4.8-5.8(5.5); zw 29.8-34.6(32.2). 4 females: l 61.8-63.5(62.9); cb 60.9-63.2(62.0); mw 10.1-10.9(10.6); iw 9.8-11.0(10.5); pow9.6-13.1(11.1); pm4 5.6-6.1(5.8); ml 5.0-5.8(5.4); zw29.5-32.6(30.6).
Morphology: It has a small
head, long face and vermiform body, small and rounded ears, mostly concealed by
hairs, short legs and long muscular tail, thick at the base, and tapering at
the end. Its fur is rough and coarsely
grizzled (Alfred & Chakraborty 2002). It has semi-plantigradefeet with short compressed claws, which are non-retractile and are used for
digging. Its eyes are small, but
glittering and snake-like, with linear erect pupils. The tongue is rough as a cat’s. The female has only four mammae.
It is similar to
Small Indian Mongoose in some respects but varies in others (Ghose 1965). NEWS
(2005-06) also consulted the skin rolls of specimens, preserved by Zoological
Survey of India, Kolkata, for noting the major morphological differences
between Herpestes palustris and H. auropunctatus. It appears that in H. auropunctatus the muzzle is dark brown and cranium gradually narrows from the orbit,
whereas in H. palustris the muzzle is black
and the cranium narrows abruptly behind the orbit so that postorbital region
appears as a constriction between frontals and cranium (Agrawalet al. 1992). Whereas the fully
grown contour hairs of H. edwardsi nyula is long, many banded and usually
coarse, the contour hairs of H. auropunctatus is
short, soft, with a few bands. The legs
of Indian Grey Mongoose are darker than body, but those of Small Indian
Mongoose are not darker than the body. However, during 2005-06, not a single Small Indian Mongoose was trapped
from the spots identified by NEWS and the inference is drawn by them that the
whole population of mongoose in north Salt Lake bhery areas is constituted of Herpestes palustris.
There is
intra-specific variation (Alfred & Chakraborty2002). It is dimorphic in colour, having both dark and light forms. In the dark form, individual contour hair is
alternately banded with black and buff-yellow, while in light form, it is
blackish-brown and straw yellow (Alfred & Chakraborty2002).
Habitat and
Associates
It is
predominantly terrestrial (partly aquatic) and fossorialanimal. It inhabits large but shallow
water bodies covered with thick growth of aquatic and herbaceous vegetation,
that is, wetland-bogs, brackish marshes, swampy edges infested with reeds, the
emergent hydrophytes, such as Phragmites karka (Retz.) and Typha angustifolia L. (Biswas1927). Various air breathing fish,
frogs, insect larvae, snails, crabs and medium to small mammals live on the
resources of these wetlands (Sewel 1934).
Its associate terrestrial
mammalian species are Prionailurus viverrinus Bennett (Fishing Cat), Lutrogale perspicillata Geoffroy(Smooth-coated Otter), Herpestes javanicus auropunctatus (Small
Indian Mongoose), Herpestes edwardsii (Indian Gray Mongoose), Viverricula indica (Small Indian Civet), Paradoxurus hermaphroditus (Common Palm Civet or Tody Cat), Felis chaus (Jungle Cat), Canis aureus (Jackal), Bandicota indica Bechstein(Greater Bandicoot Rat), Bandicota bengalensis (Lesser Bandicoot Rat), Mus booduga (Common Indian Field Mouse), Mus platythrix (Indian
Brown Spiny Mouse) and Suncus murinus (Gray Musk Shrew), all depend on these wetlands
for food and shelter.
Behavioural pattern
The Marsh
Mongoose, besides living in the self-dug burrow, also occupies other’s burrows,
mainly along the slopes of water bodies (NEWS 2005-06). It appears that the area surrounding the
occupied burrow is devoid of such clay particles unlike those of large
bandicoot rats and fresh scratch marks are seen near the mouths of mongoose-burrows.
It is mainly
diurnal and exhibits a routine exit-entry movement, coming out of the burrow
few hours after sunrise, following a particular route for foraging in its
territorial range and returning to the burrow just before sunset. It is described as mostly solitary but
occasionally gregarious and found in small troupes, particularly in the
afternoon (NEWS 2005-06). This may help
in successful joint hunting. Pairing
during the breeding season is also seen.
It is a predator
and opportunistic omnivore. It preys on
crustaceans, mollusks, crabs, amphibians, small reptiles, birds, their eggs,
insects and larvae. It is a good
rat-hunter. Occasionally, it takes snakes and frogs, but feeds mainly on fish
and the common aquatic snail Pila globosa. Sometimes it eats a wide variety of fruits,
tubers and berries as well as smaller mammalian species which it may
overpower. It often scampers off with
its prey for consuming it conveniently.
It adopts
different techniques for hunting different types of prey. The most interesting of such techniques is
that it frequently goes to the water body searching for fish through the bed of
water hyacinth without being submerged in the water. Only its feet become wet in this process. It also wades along pond banks, poking its
hands into crevices and sifting through mud to unearth frogs and
crustaceans. While hunting, it
occasionally stands up on its hind legs. For example, after seizing it throws snails and crabs against hard base
from a standing position in order to break shells open. For consuming the eggs it uses its fore-paws
to hold the egg, cracking a little hole at the small end to suck out the
yolk. Exceptionally, as per local
reports, it was seen to hunt a Cattle Egret (Bubulcusibis coromandus Boddaert,
a common resident wader or marsh bird) by seizing it by the throat. When fighting with a snake, it takes care
that the snake does not envenomate it. If it is a non-poisonous prey, the task
becomes easier for the predator.
It is alert,
ferocious and courageous animal, particularly when the young accompanies the
mother. If enraged, it can make its body
swell as a result of the erection of the body hairs. It can squirt out a fetid fluid from its anal
glands similar to Herpestes urva (Crab-eating mongoose), which acts as a means of
self-defence or territorial marking. It is generally silent, but sometimes mews,
varying with low yelps or growling in rage with bristling of the hair,
particularly of the tail.
In general, the herpestids attain sexual maturity within a year. The females are polyoestrus,
breeding twice a year; but breeding time is not fixed. Their gestation period is around 45 days and
litter size 2-4. They live for about 10
years. But the details regarding the
breeding of Marsh Mongoose are not known. However, the courtship and mating usually starts in the early summer,
that is, March onwards, and pups are seen during early June (NEWS 2005-06; Dey 2007).
Status
H. palustris is the only endemic species of mammal in
the Indian wetlands, found in West Bengal. However, no species specific action plan has been formulated for the
conservation of species and its habitat.
The Marsh
Mongoose was originally included under Schedule IV of the Indian Wildlife
(Protection) Act, 1972 and has been upgraded to Schedule II of the Indian
Wildlife (Protection) Act, 1972 (Amendment Act 2002), vide Notification
No.S.O.1085(E), dated 30th September, 2002 and recorded as ‘Endangered’
following the IUCN criteria (Molur et al. 1998; Hussain 1999; CBSG 2000; Hilton-Taylor 2000; Alfred et al.
2002; Alfred & Chakraborty 2002; Dey 2007), but its earlier status was Lower Risk/least
concern (Baillie & Groombridge 1996).
Agrawal et al. (1992)
remark, “Prior to reclamation of the Salt Lake, north 24-Parganas District, it
was very common in that area. However, at
present it is rarely seen there due to habitat destruction”. During the 21st century it is reported in one
study from only one sample area of EKW, that is, Sahebmara bheri to the western side of the EKW
and its status in this particular area was given as ‘rare’, but it was not
recorded from other four study areas, namely, Choubhaga(south), Bantala (south east), Jhagra Sisa (east) and Mahisbathan(north) (Anonymous 2004). Earlier it was
very common around water bodies of 24-Parganas (De 1994). However, Nandi et al. (1993) could not find
this species in the wetlands of north and south 24-Parganas.
Besides
trapping, on an average, 11 to 13 Marsh Mongoose have been counted per stretch
of half kilometer in the study area by NEWS (2005-06) with the help of burrow
count method. But, since it is a part of
the sample survey based on indirect method of counting, the actual population
of Marsh Mongoose in EKW could not be estimated.
Threats
Molur et al. (1998)
pointed out the threats like catastrophic events, edaphicfactors, human interference, loss of habitat and fragmentation. The halophytic vegetation of the Sundarbans during early 1930s largely dominated the East
Kolkata cluster of wetlands (Biswas 1927; Dasgupta 1973). Later on, a gradual change has taken place in water quality from polyhaline condition to almost fresh water with a change in
the profile of flora and fauna of the region. Polarization began in 1953. But the most important and massive land use
change was caused by urbanisation initiated by the
government of West Bengal since 1956. Large-scale reclamation of this wetland started in the 1960s. Thus, out of 20,000 acres of wetlands
recorded in 1945, now less than 10,000 acres are left as wastewater fish ponds
(Ghosh 2004). Besides, the ecological character of the area is adversely affected by
industrial effluents, encroachments, etc. By 1968, 36km2 of the northern Salt Lakes and 34km2 of the southern Salt
Lakes had been reclaimed leading to a rapid decline in the population of this
endemic mammal (Agrawal et al. 1992). Another satellite township at Rajarhat is proposed over 30.75km2 at the cost of the same
type of landscape.
Moreover,
changes in land use pattern over a period of time have led to conversion of
some of the largest fish farms from pisciculture to
paddy cultivation and changes in hydrological regimes are affecting ecological
balances and functions. Another problem
in the hydrology of EKW is arsenic. The percentage of arsenic which is
considered safe for consumption is 10mg/l as estimated by World Health
Organization. However, in the northern
limits of greater Kolkata, in the areas like Bhangar,Kharibari, Rajarhat, Bishnupur I and II, Gangra, Mahisbathan II the levels of arsenic has been found to be
10-15mg/l. Additionally, large numbers
of industries dump effluents without treatment into the recently laid sewers
that empty into the city outfall channels flowing eastwards. This has caused substantial amount of metal
deposition in the canal sludge and rendered the waste water incapable of
ensuring the edible quality of the fish and vegetables grown in the wetland.
The mongooses
are also illegally hunted for their fur for use in the paintbrush
industry. Because the hairs are pliant,
soft and the tip tapering to a fine point, these are preferred by both students
and artists. Mongoose hair makes
versatile, durable brushes for oil, tempera, and acrylic painting. Each animal yields about 10g of hair. Mongoose hair brushes can be identified by a
circular dark brown tip, cream coloured centre, and
dark roots (MacDonald 2001).
Conclusions
Since the
declaration of EKW as RAMSAR site for conservation of wetland ecosystem, it has
become a mandate for policy makers and planners to have an understanding
regarding the in situ situation of this ecosystem. Though the biodiversity assessment of EKW has
already been completed, its betterment and development by harnessing the
imminent threats through conservation work programmeshas to be attained with the right earnest. Time-framed and prioritized action programmes for conservation of the only extant endemic
Marsh Mongoose, whose morphometry and external
characters distinguishes it from H. javanicus auropunctatus, of the Indian wetlands are necessary to
be implemented urgently in order to save it from extinction. Although
conservation breeding for this endemic species have recommended on the ground
that there is no captive population in India or any other country (Walker &Molur 1999), no follow-up action has yet been taken
in this regard.
The reasons for
the species vanishing from one of the largest peri-urban
wetlands in the country are massive changes in land use, conversion of wetlands
and wilderness areas into built up urban settlements and also due to changes in
the fisheries practices. It is noteworthy that, among other plant species, Aldrovanda vesiculosabecame extinct from this region during the late 20th century (Cook 1996). Like this species, several other wetland
plants may become extinct if the environmental condition arenot properly maintained from the ecological point of view. It is an indication of habitat destruction of
this important wetland.
During 1964-69 a
total of 248 bird species were recorded by the Zoological Survey of India in
this region. Among them 109 avian species
(50% aquatic) have become locally extinct (Ghosh2004). For example, the eagles were last seen here in 1992 (Unpublished report
of Prakriti Samsad, an
Non-Government Organization of Kolkata),15 wild fish (Sen 1941) and 12 reptilian species (Sewel1934) have become rare here. Among mammals, Herpestes edwardsii, Viverricula indica, Paradoxurus hermaphroditus, Felis chaus, Canis aureus and Lutrogale perspicillatahave also become rare in EKW along with Herpestes palustris (Anonymous 2004). Hence, this is an 'alarm
call' for protection of the dwindling population of Herpestes palustris and other rare wild denizens of EKW.
The Marsh
Mongoose H. palustris Ghose,
1965 is distinct from the H. javanicus auropunctatus (Hodgson, 1836) in terms of both
morphological and cranial characters and we are of the opinion that this
species needs to be resurrected out of the synonymy of H. javanicus.
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