STATUS OF THE MAMMAL FAUNA IN SUNDARBAN TIGER RESERVE , WEST BENGAL-INDIA Sectional

Sundarban Tiger Reserve (2,584.89 km) in West Bengal is a part of the world’s largest estuarine wetland and the only mangrove tigerland, spread over India and Bangladesh. Its plant associations exhibit a great generic/species diversity and offers habitats of many rare and endangered mammals. The dense thickets of Heritiera fomes, Nypa fruticans and Phoenix paludosa form the prime habitat of Panthera tigris tigris. This tigerland is also the abode of a good number of its prey and other associated mammal species. A one-year (January-December 2010) study was conducted with the frontline forest department staff to investigate the distribution and status of the mammalian species found in this thirty-eight years’ old tiger conservation area, involving literature review, questionnaire and ground surveys. This has revealed shrinkage of the mangrove swamp habitat and a number of mammal species in decline due to extensive anthropogenic and natural threats. Out of forty nine extant species recorded (eight orders: twenty three families), four are globally endangered, four vulnerable and two near threatened as per IUCN Red List. Alarmingly, fifteen mammal species were found on only rare occasions. In addition, six species (two orders: three families) had become extinct during the last two centuries. Though distributed over all forest block areas, the frequency of tigersighting was recorded more from Sajnekhali Wildlife Sanctuary and the buffer areas than Sundarban National Park or the core area. High-priority wildlife conservation, proper implementation of the tiger action plan, further infrastructural development and effective joint forest management are essential for saving this tigerland.


Introduction
In 1947, the Radcliff Mission awarded the western Sundarbans (the Hooghly-Matla estuary) to West Bengal, India and the eastern Sundarbans to East Bengal (now Bangladesh).The western Sundarbans in North and South 24-Parganas districts form about 40% of this largest estuarine wetland-cum-TAPROBANICA, ISSN 1800-427X.October, 2011. Vol. 03, No. 02: pp. 52-68. © Taprobanica Private Limited, Jl. Kuricang 18 Gd.9 No.47, Ciputat 15412, Tangerang, Indonesia.mangrove tigerland and 60% falls in Bangladesh.Sundarban Tiger Reserve (STR) is located a little south of the Tropic of Cancer between 21° 32' -22° 40' N and 88° 05' -88° 10' E. It is bounded by the rivers Kalindi, Raimangal and Harinbhanga on the east along the Bangladesh border, the rivers Bidya and Matla on the west, the Bay of Bengal on the south and the khals (erosion channels) Bara Herobhanga and Gomdi as well as the rivers Pitchkhali, Kapura, Korankhali, Raimangal and Kamlakhali on the north (Fig. 1).The surface area of STR is 2,584.89km 2 , of which the forest cover is 1,680 km 2 and 905 km 2 is under water regime (Table 1).STR is a network of rivers, channels and creeks that forms innumerable flat islands, which are submerged mostly during the high spring tides and partially during the ordinary high tides.There are no villages within STR, but there is a 65 km forestvillage interface on the north-western side that is prone to frequent tiger-straying and livestock depredation (Vyas, 2004).The sources of all the rivers flowing through STR being progressively silted up, these are getting more brackish and shallow year after year.By repeated scouring during the ebb tides, innumerable small khals have been formed.Their banks are as high as two metres in some places, but shallow in the interior islands due to repeated silt deposits.The climate in STR is subtropical, where the temperature varies from 20 °C (December-January) to 33 °C (June-July), the average annual rainfall is 1,763 mm (75% received during June to September) and the humidity level is 70-80%.This region is often exposed to severe storms and cyclones.
STR is one of the foremost reserves of Project Tiger, which was launched in 1973 to save the Bengal tiger from extinction (Chaudhuri & Chakrabarti, 1979d).In 1984, Sundarban National Park was declared with an area of 1,330.12km 2 , which was also designated as the inviolate core area including the primitive zone or gene pool at Chamta block.In 1987, this park was recognized as a World Heritage Site (UNESCO) under Criterion IV-Habitats of rare and endangered species.The Sundarban was also included in the World Network of Biosphere Reserve in 2001.The Government of India has recommended the Sundarban as a Ramsar Site (a wetland of international importance).In 2007, an area of 1,699.62 km 2 was notified as the Critical Tiger Habitat (CTH) by including additional area of 369.50 km 2 (Reserve Forests) to the existing core.This CTH consists of nine blocks divided into forty two compartments: Matla (four), Chamta (eight), Chhotohardi (three), Goasaba (four), Gona (three), Bagmara (eight), Mayadwip (five), Netidhopani (three) and Chandkhali (four).The buffer zone of 885.27 km 2 (as revised in 2009) includes six blocks (twenty nine compartments).Of these, Panchamukhani (five) and Pirkhali (seven) blocks form Sajnekhali Wildlife Sanctuary (362.42 km 2 ), the gateway to this tigerland.The balance area in Arbesi (five), Jhilla (six), Khatuajhuri (three) and Harinbhanga (three) blocks is earmarked as a multiple-use zone for regulated harvest of various forest resources for meeting the local needs.
The study area is divided into four territorial ranges including six beats: Sajnekhali, Basirhat, East and West.STR is administered by the field director along with one deputy and two assistant directors.(Naskar & Mandal, 1999;Raha & Saha, 2004;Gopal & Chauhan, 2006;Chaudhuri, 2007).

Material and Methods
After conducting a literature survey on the mammalian diversity in STR, a database was prepared for facilitating field verification during the study period (January-December 2010).A sample questionnaire survey was also conducted on a set Working inside the hostile mangrove habitat, which is approachable and traversed only by the watercrafts, is very difficult due to inaccessibility, absence of any forest road, natural obstacles and lack of logistic infrastructures.The stiltroot/pneumatophore-infested and muddy forest floor prevents any transect survey.Hence, the field study was conducted with the help of the stationed and mobile forest department staff, who are engaged in regular patrolling and monitoring.A number of field visits (12 x 3= 36 days) to the site were also made by the author.

Parameters
Both up-and down-stream surveys were carried out by using a mechanized boat at a speed of 1.5-3 km/h along the rivers and creeks from 5:30 h to 19:00 h.Observations were made from both the front and back of this vessel with a binocular.The boat-survey was, however, suspended at night due to poor visibility and security-risk.At night, the observations were made from the wire-caged watch towers at Sajnekhali, Sudhanyakhali, Dobanki, Netidhopani, Burirdabri, Jhingakhali, Gazikhali, Mayadwip, Gabbani, Arbesi-1 and Haldi by using a search light.
The mammal fauna were listed on the basis of direct sighting, indirect methods (e.g.foot prints, faeces, scratch marks, calls, etc.), questionnaire survey and departmental records (census, monitoring, casualty and rescue data).The mammal species sighted were identified and classified by consulting a current field handbook (Bahuguna & Mallick, 2010).

Threats:
The mangrove ecosystem is so fragile that any interference may lead to extinction of various components and also the ecosystem as a whole in the long run.Being the only forest in a region inhabited by 3.9 million people (2001 census), more than 5% of whom are estimated to enter forest for fishing, honey-collection, wood-cutting and shrimp fry-collection, the study area is prone to heavy biotic pressure.Between 1994Between -1995Between and 2001Between -2002, ten tigers were poached while straying into the fringe villages.Though poaching of the tiger has been reduced, poaching of the prey species like the spotted deer and wild boar has led to prey-depletion.Although snaring is a traditional practice along with traps of different kinds, the spotted deer are also killed by gun-shot by following their track.The consumption of venison is largely local, but the actual impact of this problem is unknown.Deer meat and skin have been seized recently from the fringe villages like Samsernagar as well as the distant towns like Baruipur.
Besides, illicit felling of the small timber and fuel wood, unauthorized fishing, destruction of the spawns of various fish in the course of large-scale catching of the tiger prawn (Peanacus monodon) spawns, are reportedly high in the buffer zone because of rapid increase in the human population, poverty and unemployment in the reclaimed areas.All these have adverse effect on the ecological balance, leading to elimination of the floral and faunal species.
Often the Sundarban suffers from severe storms and cyclones.During the super cyclone Aila (May 2009), the frontline shelter vegetation was damaged severely in some vulnerable areas.Many deer were swept away to the fringe villages and, in some cases, the villagers captured them and handed over to the forest staff, but some might have been poached by the distressed people for consumption (Banerjee, 2009).Except one case of tiger-straying into a fringe village, there was no report of any tiger's death during the study period.Inasmuch as the wild islanders are excellent swimmers and possibly warned of the incoming natural calamity in advance, most of them could escape and perhaps took refuge in the unaffected highlands with dense vegetation.
The reduced freshwater flow from the Ganges and its distributaries and increase in salinity (range varying from 0.4% to 27.5%) of the water and soil has caused floristic changes and shrinkage of the tiger's prime habitat, i.e.Sundari (Heritiera fomes), Hental (Phoenix paludosa) and Golpata (Nypa fruticans).Gradual sinking of the delta due to rising sea levels is also reported.The islands or sandbars like Bedford (Suparibhanga), Kabasgadi, Lohachara (in river Hooghly) and New Moore /South Talpatti, 2 km from river Harinbhanga, have already disappeared and the Ghoramara Island (80 km 2 ) has submerged.Water pollution sources include the exhaust oil from the watercrafts, sewage and chemical effluents upstream.Soil erosion and silt deposition, uncontrolled tourism (about one hundred thousand people visiting the Sundarbans every year), straying of tigers from seven forest blocks, viz.Pirkhali, Panchamukhani, Arbesi, Jhilla, Chandkhali, Goasaba and Harinbhanga into the fringe villages (21 villages mostly affected) and depredation on the domestic animals, killing of human beings entering the forests by the tigers and the porous international border (about 20 km) with Bangladesh are some of the serious management problems in STR.Moreover, there are organizational (frontline staff) and infrastructure deficiencies.Project Tiger Directorate assessed that comparatively an extensive area is covered by a staff in the Sundarban-Ranger 215.42 km 2 , Forester 112.39 km 2 and Guard 25.34 km 2 (GOI, 2005).

Results and Discussion
Forty nine extant species (eight orders: twenty three families) were recorded during the present study, out of which four are globally endangered, four vulnerable and two near threatened as per IUCN Red List and, alarmingly, 20 mammal species (40.81%) were found only rarely (Table 3).Fifteen species are, however, included in Schedules I and II of the Indian Wildlife (Protection) Act, 1972.Besides, six species (two orders: three families) were extinct during last two centuries due to habitat degradation and ecological changes (Table 4).are present in the fringe areas.Among the civets, the small Indian civet (Viverricula indica) is common in the reclaimed lands along with the palm civet (Paradoxurus hermaphrodites), which is seen occasionally.At present, the main ungulate prey species in STR are the cheetal (Axis axis), which are found in small and large herds, and the wild boar (Sus scrofa), only loners of which are sighted.The Great one-horned rhinoceros (Rhinoceros unicornis), small one-horned rhinoceros (R. sondaicus), barking deer (Muntiacus muntjak), swamp deer (Cervus duvauceli), hog deer (Axis porcinus) and wild buffalo (Bubalus bubalis) are already extinct (Bahuguna & Mallick, 2004;Mukherjee, 1980).During early 1990s, Project Tiger estimated the populations of the cheetal (31,000), wild boar (12,000) and rhesus macaque (38,000).Rhesus macaque (Macaca mulatta), the only primate in the Sundarbans, is quite abundant.They are gregarious and found in scattered groups of 30-40 individuals.At Sudhanyakhali, this monkey is abundant seasonally and its numbers generally decline after April, when most of them migrate to the interior forests, and increase from October onwards with the start of the tourist season.Their mating season is usually between February and July.
The rivers and near-shore waters are the abode of five aquatic mammals: the dolphins and porpoises.Among them, the Gangetic dolphin (Platanista gangetica) and Irrawady dolphin (Orcaella brevirostris) are common along the upper part of the rivers Matla, Bidyadhari, the confluence of Raimangal and Jhilla at Bagna, Amlamati and at Sudhanyakhali.Rarely, the black finless porpoise (Neomeris phocoenoides) is met with.An Indo-Pacific hump-backed dolphin was sighted and photographed a few years back near Sajnekhali.There are no recent records of sighting any Pantropical spotted dolphin in the Sundarban.
Among the rodents, Bandicota indica, B. bengalensis and Mus booduga are quite abundant.The white-bellied tree rats (Rattus rattus arboreus Horsfield, 1851), nesting in bunches of leaves and twigs, were also observed.Holes and nests of the five-striped palm squirrel (Funambulus pennantii) in the tree trunks and branches were also discovered.
All the previous censuses  in STR recorded a population of ±250 tigers on the basis of pugmark analysis (Table 5).Block-wise abundance of the tiger in 2004 census was also assessed (Table 6).Accordingly, tiger concentration was calculated to be <10 km 2 /tiger.Since 2006, a new methodology-"Monitoring of tigers, co-predators, prey and habitat" through direct sighting, collection of pugmarks and scats, roaring and other signswas introduced in Sundarbans.Data were available during 2007-2008 (Table 7) and 2008-2009 (Table 8).The present survey, based on direct sighting and indirect evidences along the river/creek banks, bank-side mangroves and at the watchtower locations, revealed that the tigers were present throughout the landscape with varying abundance.In all, the tiger was sighted 417 times (mean 13 in September and maximum 56 in January) in fourteen forest blocks during the study period (Table 9).Such sighting was frequent during the winter and summer months.Maximum sighting was recorded on the north-western forest blocks like Pirkhali (43.16%),Netidhopani (18.46%),Arbesi (13.18%) and Panchamukhani (5.75%).Although tiger was not sighted in Mayadwip block, the pugmarks of a mother along with a cub and (separately) those of an adult male were traced in this island a number of times in May.  ur cubs were also sighted, two each at Pirkhali and Chhotohardi in November.However, the cubsighting ratio is very low in the study area.In all, only five cubs were found in three out of fifteen blocks (20%).Earlier, the author found the signs of hunting a deer by the tiger at Burirdabri (Khatuajhuri block), opposite Bangladesh.There was a resident tiger family including a cub in this small island.
During the study, the tigers used different habitats for definite purposes like shelter, breeding, hunting, etc.This habitat use pattern vis-à-vis the forest types are recorded separately (Table 10).Out of thirteen forest types/associations, nine (88%) are used as habitats (shelter= 72%, breeding= 7% and hunting= 9%) and four types (12%) are not normally preferred by the tigers.Due to frequent shifting or island-migration and occupation of new habitat by the tigers, the habitat occupation and range of movement varies considerably from individual to individual and from time to time, mainly depending on availability of the prey species-be it wild, domestic or human beings entering forests with legal permits or illegally.
A review of the human-tiger conflict data showed only one case of tiger poaching during the twenty first century (Table 11).Moreover, the incidences of human deaths due to tiger depredation in the forests are also on the wane (Fig. 2).But tigerstraying cases have recently been increased greatly, particularly after the onslaught of cyclone Aila in 2009 (Table 12).The straying tigers were captured with the help of the villagers and committee members and rehabilitated in the wild.Similarly, a good number of other mammals were also rescued and rehabilitated (Table 13).
Shrinkage of habitat due to tides, salinity of creek waters and pneumatophore-infested forest floor have offered a very adverse habitat conditions for the tigers.Nevertheless, they were reportedly more or less present in all the fifteen blocks of STR since early 1970s and their predatory aberration was also reported as they used to migrate from block to block (Chamta-Matla to adjoining Chandkhali-Netidhopani-Panchamukhani-Pirkhali) (Chaudhuri & Chakrabarti, 1980).But their abundance is variable in different blocks.Earlier, the tigeroccupancy in STR was reported to be 1,586 km 2 (Jhala et al., 2008).
The Sundarban is a unique habitat (Vyas, 2005), where the tiger occupies the pinnacle of both the aquatic and terrestrial food web.While the males change their territory more, the females tend to hold a territory for comparatively longer periods.The territory of a male also overlaps the territories of more than one female.The cubs are reared exclusively by the mother and they remain attached to her for up to two and half years.The female cubs often occupy territories or home ranges adjacent to that of their mother.During the daily activity, every tiger records its presence while walking on soil amenable to receiving its pugmarks.While the tiger pugmarks were found along the banks of the creeks and rivers, their scats (wet as well as dry) were found at Harinbhanga 3, Jhilla 1, 2 and 3, Arbesi 5, Chandkhali 2 and 3, Bagmara 3 and 8, Chamta 4, Matla 3, Chhotohardi 3, Panchamukhani 5, Khatuajhuri 2, Mayadwip 1, Pirkhali 2 and also near the sweet water ponds visited by the tigers like Dobanki camp (Pirkhali 5), Sajnekhali camp (Pirkhali 1), Choragazi (Panchamukhani 3), Jhingakhali (Arbesi 1), Tushkhali (Khatuajhuri 1), etc.The nail marks (scratching) of some tigers on the trees like X. granatum (males), S. apetala and Avicennia spp.(females) were also observed.The tiger-roars were heard mostly between the premonsoon and the pre-winter, but rarely thereafter.These calls are generally related to the hunting, mating and sometimes while the mother moving with her cubs encounters an enemy.
The habitat pattern in STR is uniformly monotonous, not broken by such landscape features that are known to provide specific cover for the tiger in other areas.The Heritiera and Phoenix thickets, which are not either regularly inundated or inundated for a short period, form a favoured tiger's den and signs of its presence is commonly found in the plant consociations of Rizophora-Bruguiera, Avicennia-Oryzha, Excoecaria-phoenix, Exoecaria-Ceriops, pure Ceriops and pure Oryzha.The natural prey animals occupying the tiger niche are the cheetal, wild boar and rhesus monkey.During the study, the encounter rates of the cheetal was found to be high (3.8/km 2 ) compared to those of the wild boar (0.14/km 2 ) and rhesus macaque (1.2/km 2 ).Large groups of the deer were seen on the higher grounds, which are generally not inundated during the high tides.The Rhesus monkeys were commonly found on the Keora (S. apetala) patches.
The secondary predators are mainly the fishing cat and, to a small extent, the jungle cat and leopard cat.The fishing cats dwell amidst the dense vegetation associated with the marshes and mangroves (Mallick, 2010a).The encounter rate of the fishing cat was 0.03/km 2 .The pugmarks of the leopard cat were distinguished from those of the fishing cats on the basis of absence of any nailimprint on the soil.Otters were rarely sighted (encounter rate 0.009/km 2 ).
Among the dolphins, the Gangetic dolphin is frequently found in the eastern side, particularly in the river Raimangal, the upper part of which is fed by some freshwater flow.It descends during the monsoon season when salinity is low but appears to decrease in number during the summer (Mallick, 2011).This migration also seems to be associated with the migration and dispersal of fishes, which are their main prey.The Irrawaddy dolphins are not found in the more saline Matla-Hooghly estuary.
Seventeen individuals were seen in the premonsoon and twenty two in the post-monsoon months.The Irrawaddy dolphins were recorded mostly in the lower reaches of the river Raimangal and a few were also observed at the Jhilla and Amlamati.There was no sighting record of this species in the river Matla, which is a habitat of the Ganges dolphin.The black finless porpoise were rarely found in the rivers near the estuary.
The Sundarban tiger exhibits certain distinctive morphological adaptations that make it particularly suited to the mangrove habitat (Barlow et al., 2010).Unlike the mainlanders, these islanders are much smaller (suggesting insular dwarfism), more muscular with leaner frame and lesser body mass (±100 kg).The stress factor associated with changes in their natural habitat and the availability of the smaller prey species is often related to such phenomenon.
In the study area, two adult female and three adult male tigers were captured, radio-collared and released back into the forests.Of them, a six-year old male (Netidhopani tiger) was captured, while straying into inhabited areas, and weighed only 97 kg.Its neck was measured 53 cm against the normal size of 65-75 cm.Another adult tiger (Khatuajhuri male), which was caught at Malmelia village of Basirhat range, was also found to be frail and underweight (108 kg) with the neck-size of 58 cm.
The natural prey animals of the Sundarban tiger are also smaller (e.g., the Cheetal, wild boar and rhesus monkey), compared to the heavier sambar or gaur in the mainland.It is assumed that a smaller islander needs lesser food.Less body weight enables it to move through the muddy terrain with minimum loss of energy, otherwise the feet of a heavy-weight tiger would sink deep into the muddy soil during its movement along the banks.Besides, these islanders are capable of leading an almost amphibious life unlike the mainland tigers.Besides, its prey species like the cheetal and wild boar are also semi-aquatic.The rhesus macaques were also found to migrate in search of food.Hence, the predator has to change their territory following its prey species.Garga (1948) recorded a tiger swimming over 6 miles in the river Hooghly.There were records of tiger swimming more than 20 km, negotiating from one island to another, crossing more than one river.A problem tiger, which was released in the southernmost limit of STR, came back to the capture area on the north by covering about 100 km and crossing a good number of channels within a month.Tigers were seen swimming at right angle parallel to the current and changing their course, when they felt disturbed.In April, a tiger swam of continuously in the morning for about three hours in the rivers Mayadwip and Bidya, before entering forests at a different location.The radio-collared tigers were recorded to cross, on the average, ten channels (mean width 25 m and maximum width 200 m) per day.In STR, the tigers have been recorded to cross larger (>5 km width) channels as well.From the sighting records, it appears that the tigers move even during the daytime in an undisturbed area.
Apart from the long-stretch swimming, the tiger has adapted to changed food habits.An earlier study on the scats of the tiger at fifty three locations in STR has revealed that in addition to its natural terrestrial prey species like the cheetal (32.35%), wild boar (38.23%), rhesus macaque (2.94%), its food included the fish (2.94), crab (4.41%), water monitor lizard, Varanus salvator (7.35%), turtles (1.47%), fishing cat (1.47%), birds (2.94%) and Phoenix leaves (Sanyal, 1993(Sanyal, & 1999c)).The tigers also ate honey and, before breaking the combs, smeared themselves with mud to avoid the stings.Remains of the venomous snakes (Ophiophagus hannah and Naja naja) were also detected in the stomach of a dead tiger at Netidhopani, after onslaught of the Aila.In case of the man-eating within the forest areas, the victims were mostly fishermen.Only 5% of the tigers were reported to be man-eaters (Sanyal, 1998).Its frequent straying into the villages for hunting the domestic animals often causes retaliatory killing by mobs.
In STR, the deer is the most important herbivore in terms of number and biomass and their grazing and browsing is the main factor in structure of the vegetation cover.The fodder grass is limited in STR and includes the Dhani grass (Porteresia coarctata) as well as patches of Saccharum spp.grown on the sea-facing mud flats, which are good grazing grounds for the deer, but except for the newly generated succulent tips, the remaining parts are untouched.However, the cheetals prefer the Keora leaves, fruits and buds and also leaves of the TAPROBANICA VOL.03: NO. 02 Baen, Genwa and Kankra.They were seen to stand erect on their hind legs and browse the Sonneratia leaves.
The Keora fruits and leaves are also liked by the rhesus monkeys.The succulent leathery leaves of other mangrove trees are also taken by them.During June-July, the monkeys throw fruits on the ground, which are consumed by the cheetals.The monkey troops also drop the twigs and leaves, which are eaten by the deer.
The habitat of the wild boar is the tangled mass of Garan, whose extensive breaks harbour the sounders.The freshwater ponds dug in the forests near the watch towers attract the deer, pigs and tigers.The monkeys, however, consume the dew drops from the leaves of Keora.Like the tigers, the rhesus macaques feed on hermit crabs to supplement their diet and for this purpose, they have even to dexterously manoeuvre their movements to avoid landing their feet on needlelike piercing pneumatophores, which speaks of their obligatory dependency on this diet.
The size of a tiger's home range depends on prey abundance and in case of the males, access to the estrus females.In the study area, the mean distance moved by the radio-collared tiger/tigress per day was found to be 4.64 km 2 , whereas the maximum distance covered/day was 13.5 km 2 .While following a tiger on the bank of the Nabanki khal, it was observed to move a distance of 1 km in ten minutes.A radio-collared tigress moved over a radius of c. 30 km 2 during a week (Mallick, 2010b).However, it could move much faster while chasing its prey.
The total mangrove forests of India and Bangladesh, having a viable tiger population, can potentially share their gene pool.Migration of the tigers between these two segments was anticipated, but there was no proof in the past.But during 2010, evidence of such territorial shifting was known.The straying Khatuajhuri male, blind on the right eye with signs of territorial fights, which was captured on 20 th May, radio-collared and released in the nearby forests on 22 nd May, crossed the river Harinbhanga and strayed into the Bangladesh Sundarban, where it remained in the island of Talpati till his collar stopped functioning on 5 th August.Hence, no further information regarding its movement was available.

Recommendations
Saving the tigers is essential not only for the biodiversity protection but also to safeguard the national identity.Project Tiger authorities should take immediate steps to conserve and expand mangroves, while preventing the poaching.The government should also take stringent measures to curb the immediate threats of environmental degradations for long-term survival of the floral and faunal resources through habitat improvement programmes.High priority for conservation, further infrastructural development and effective joint forest management are essential for saving this last stronghold of the Bengal tiger in India.The real challenge is to implement the tiger action plan by reconciling the competing interests of the multiple stakeholders and regulating the heavy biotic pressure, while making a safe and healthy habitat for the tigers and other species in this unique landscape with active participation of the local communities.

Fig. 1 :
Fig.1: Location of the study area within the Ganges River estuary complex in the Bay of Bengal.

Table 01 :
Blockwise distribution of the reserve forest in STR

Table 2 :
Landscape characteristics in STR (from Jhala et

Table 3 :
Checklist and status of extant mammalian species in STR (C: common, R: rare, EN: endangered, VU: vulnerable, NT: near threatened, LC: least concern, DD: data deficient)

Table 4 :
List of extinct mammalian species in the study area Apart from the tiger, there are no other large terrestrial carnivores in the Sundarbans.The small carnivore community is composed of the leopard cat (Prionailurus bengalensis), fishing cat (Prionailurus viverrinus) and jungle cat (Felis chaus).The creeks fringing the mangroves and associated mudflats harbour the diurnal smooth Indian otter (Lutra perspicillata) and the nocturnal small-clawed otter (Aonyx cinereus), which live on the fishes, crustaceans and mollusks.The jackal (Canis aureus) and Indian fox (Vulpes bengalensis)

Table 5 :
Tiger census (plaster cast method) in STR

Table 7 :
Month-wise tiger monitoring data in STR  during 2007-2008

Table 8 :
Month-wise tiger monitoring data in STR  during 2008-2009

Table 9 :
Month (M)-wise tiger sighting records in STR during 2010 survey

Table 10 :
Habitat types used by tigers in STR

Table 11 :
Natural death cases (ND) and poaching (P) of mammalian species in STR

Table 12 :
Tiger straying incidents detected in STR

Table 13 :
Rescue and release of mammalian species other than tiger in STR