OBSERVATION ON VERTEBRATE FAUNA OF D'ERING MEMORIAL WILDLIFE SANCTUARY, ARUNACHAL PRADESH

The D'Ering Wildlife Sanctuary formerly known as Lali Sanctuary is located at Pasighat Forest Division, East Siang district, Arunachal Pradesh. It is one of the least faunistically explored area in India. So, special efforts were made to survey wildlife of the sanctuary during 2000-2001 and 2001-2002. The paper mainly deals with the vertebrate fauna i.e., mammals, birds, reptiles, amphibians and fishes. Nevertheless special emphasis has been given on mammals and birds only. Very little information is available on some higher vertebrates of Arunachal Pradesh from the works of Jayaram and Majumder (1964), Ripley (1980), Saha (1982), Moll and Vijay (1986), and on faunal elements of Namdhapa Biosphere Reserve (Datta and Barman 1985, Sanyal and Gayen 1985, Saha 1985). In the present paper an attempt has been made to give an account of the vertebrate fauna with special reference to mammals and birds occurring in the D'Ering Wildlife Sanctuary area under report.


INTRODUCTION
The D'Ering Wildlife Sanctuary formerly known as Lali Sanctuary is located at Pasighat Forest Division, East Siang district, Arunachal Pradesh.It is one of the least faunistically explored area in India.So, special efforts were made to survey wildlife of the sanctuary during 2000-2001 and 2001-2002.The paper mainly deals with the vertebrate fauna i.e., mammals, birds, reptiles, amphibians and fishes.Nevertheless special emphasis has been given on mammals and birds only.
Very little information is available on some higher vertebrates of Arunachal Pradesh from the works of Jayaram and Majumder (1964), Ripley (1980), Saha (1982), Moll and Vijay (1986), and on faunal elements of Namdhapa Biosphere Reserve (Datta and Barman 1985, Sanyal and Gayen 1985, Saha 1985).In the present paper an attempt has been made to give an account of the vertebrate fauna with special reference to mammals and birds occurring in the D'Ering Wildlife Sanctuary area under report.

STUDY AREA
The D'Ering Wildlife Sanctuary of East Siang District, Arunachal Pradesh (Map 1) lies in between 95° 15' to 95°30' east longitude and 27°50' to 28°50' to north latitude.It is bounded by Sibia river in the east, Siang river in the west, Central Wildlife Division of Ying Kiong in the north and North Lakhimpur district of Assam in the south.A large number of jheels, nullahs and waterbodies are present in and around the sanctuary.The total area of the sanctuary is 1,638.4hectares.The sanctuary was damaged heavily by flood in 2000 resulting in the decline of wildlife population.

MATERIALS AND METHODS
During 2000-2001 and 2001-2002, two surveys were made on foot along the forest trail while along the river course country boat was used.The observations were carried out from early morning to sunset by using binocular, telescope for visual recording of higher vertebrates.The nocturnal observations were carried out by using headlight, spotlight and three-celled torch.Sometimes mist nets were used to capture small birds and release after identification.Hand-made drag net was ~ used for collections of fish samples.

RESULTS AND DISCUSSION
The faunal resources belonging to higher vertebrates (mammals, birds, reptiles amphibians and fishes) are as follows: Mammals (Figs. 1 and 2) Twenty-three species of mammals belonging to 16 families have been recorded (Table 1) from this wildlife sanctuary.Out of 23 species of mammals 2 species namely Small clawed otter (Amblonyx cinerea) and Common otter (Lutra lutra) are rare and recorded along the Sibia river and its tributaries.The only aquatic mammal, the Gangetic Dolphin (Platanista gangetica) was recorded along the course of the Brahmaputra river.Only a few individual of this species was observed.According to Sinha et al., (2003) a total of about 2000 dolphins have been estimated in the Ganga and the Brahmaputra river system.In the 19 th century dolphins were plentiful in the entire distributional range.But their population is declined due to shrinkage of many smaller tributaries in upper reaches of the Ganga where they were found earlier and nowadays killed both incidentally or directly.The IUCN recently change the status of the species from vulnerable to endangered (Baillie and Groombridge, 1996).Though the species, wild buffalo (Bubalus bubalis) has become very rare but it is common only a few protected areas of Assam e.g.Kaziranga, Manas and Dibru-Saikhowa and also recorded from Kachar district of southern Assam (Choudhury, 2002).Their population is under severe threat due to depletion of suitable swamp and grassland habitat, large scale poaching and communal hunting (Ranjit Sinh et al., 2002).Two herds of the species, one herd comprising of four adults and three juveniles and the other herd comprising of four adults have been recorded around the Sibia river bed.The tiger (Panthera tigris) population in this sanctuary is very low.The presence of tiger in this sanctuary could only be ascertained by a few recent spoor marks and few traces of recent hunting.In Arunachal Pradesh though there is excellent ever green vegetation and plenty of water, the tiger population is less due to limited number of prey animals (Sankhela, 1977).The invasion of elephant (Elephus maximus) is noted by the presence of their foot-prints and bolus.The personnel of Forest Department reported that in the month of May and June the herds of elephant about 15-20 in a group migrate to the sanctuary from adjacent Mohanbari and Sadia forest of Assam.They reside here for two to three months and again return to Mohanbari and Sadia forest of Assam in the month of September and October.This seasonal migration to Lali Sanctuary is due to scarcity of food in Mohanbari and Sadia forest for cultivation and abundance of food in Lali Sanctuary.The deer groups of the family Cervidae and the wild boar (Sus scrota) of the family Suidae are less in population.TheWild Boar, Barking deer, Sambar etc. were once common in the sanctuary as stated by forest personnel.But at present their population became very low due to illegal killing of the animals for meat and skins.Chakraborty and Sen (1991) stated that in recent years wild animals came in close contact to the people who realised the commercial value of the forest products and this further encouraged them to the killing of animals.
Birds  While conducting the field survey during 2000-2001 and 2001-2002, 123 species of birds belonging to 39 families (Table 2) were recorded.The avifaunal components belong to both passerine as wel1 as non passerine fonns.In all 107 species are resident and 16 species are migratory.The wetland birds belonging to 13 families i. e., Podicipedidae, Pelecanidae, Phalacrocoracidae, Ardeidae, Ciconiidae, Anatidae, Accipitridae, Rallidae, Glareolidae, Charadriidae, Laridae, Alcedinidae, Motacil1idae, were recorded during the survey.The water birds were mostly observed along the Brahmaputra, Sibia and Siang rivers.Among the water birds two groups of Spot-billed Pelican (Pelecanus philippensis) were recorded, one group comprising of 41 in number in April 2001 and the other group comprising of 28 numbers in April 2002 along the course of Sibia river.The status and distribution of this species is globally threatened/vulnerable and over al1 population is declining (Alfred et al., 2001).The Osprey (Pandion haliaetus) was also encountered during the survey.It is to be noted that this species belonging to schedule-I of the Indian Wildlife (Protection) Act. 1972 and its further amendments, is also listed as IBA species and enlisted in APPENDIX-I of the CITES.

Tringa nebula ria
Green Shank Rare R S.L.M.

Hoplopterus in die us
Red Wattled Lapwing Rare R S.L.M.

Pluvialis dominica
Eastern Golden Plover Abundant M

Gallinago minima
Jack Snipe Rare M

Chlidonias hybrida
Whiskered Tern Rare R

Sterna aurantia
Indian River Tern Abundant R

Larus ichthyaetus
Great Blackheaded Gull Rare M

Graminicola bengalensis
Large Grass Warbler Rare R

Prinia socialis
Ashy Wren Warbler Rare R

Phoenicurus ochruros
Black Redstart Rare R

Orthotomus sutorius
Tailor Bird Rare R

Motacilla alba
White Wagtail Common R

Motacilla cinerea
Grey Wagtail Rare R

Nectarinia asiatica
Purple Sunbird Rare R

Zosterops paJpebrosa
White-Eye Rare R

Pyrrhoplectes epauletta
Goldheaded Black Finch Rare R Among the aquatic birds the ducks and geese (Anatidae) as stated by Alfred et al., (2001) are the winter migrants to the Indian sub-continent.There are some species of water birds whose southernmost palaearctic breeding range extends into Indian boundaries in Ladakh, Kashmir (Ruddy Shelduck, Pintail and Barheaded goose) and sometimes in central and eastern Himalayas.
Nevertheless they behave like a true winter migrant in spreading over northern peninsular India.species has undergone an alarming decline throughout its former range, as its grassland habitat has been lost due to cultivation or degraded by over grazing (Rahmani et aI., 1991).Its past distribution ranges from southern Uttaranchal to upper Assam, through the Nepal Terai, Bengal Duars and Brahmaputra river valley (Ali and Ripley, 1969;Rahmani et aI., 1991).The known population of less than 300-400 individuals is at serious risk from further habitat loss, warranting its inclusion in the IUeN list of endangered species (Baral et al., 2002).As regards Black Bulbul (Hypsipetes madagascarinsis), though this species is the resident bird in Arunachal Pradesh (Ripley, 1982), only three birds of this species were recorded during survey.
In overall, diversity of wildlife species particularly higher vertebrates in D' Ering Memorial Biosphere Reserve, Arunachal Pradesh, however, represent 20 species of mammals, 38 species of birds, 10 species of mammals, 9 species of birds and 30 species of mammals, 18 species of birds respectively (Table 3).
The divisional boundary of Pasighat Wildlife Division is bounded by Dibang Valley district in the east, West Siang district in the north and west and North-Lakhimpur district of Assam in the topography is characterised by the beautiful valley of Siang river with numerous streams, situated along the foot hills of eastern Himalaya.The climate of the terrain may be divided into four seasons (i) pre-monsoon from March to May, (ii) south-west monsoon confined to June to September, (iii) post monsoon, October and November, (iv) winter season mainly from December to February.The hottest months are July and August with the minimum temperature of 24°C and the maximum temperature of 33°C.The coldest months are December and January with the minimum temperature near about 12°C and maximum 22°C.The total annual rainfall ofPasighat Forest Division is 6508.5 mm.The maximum amount of rainfall is in the month of July i.e., 1243 mm. and monsoon shower ends in September.The soil of Pasighat Wildlife Division is of new alluvial type.The vegetation of this region are of mixed riverine and mixed moist deciduous type which include small and tall trees, shrub, bamboograsses, climbers, orchids etc.The thorny trees like Jujuba, Zizyphus jujuba Lamk are very common in the forest.

Table 2 .
: List of Avifauna recorded in D'Ering Memorial Wildlife Sanctuary (R : Resident bird, M: Migratory bird, S.L.M.: Subject to local migration) Sch -I = Schedule 1 of Indian Wildlife (Protection) Act.
It has been noted that a good number of Collared Pratincole (Glareola pratincola) observed during the survey.It was also noted that they are crepuscular and forms unispecies foraging group while frisking on the surface of water and above.The families Ardeidae, Ciconiidae, Charadriidae, Rallidae, Motacillidae are the major components of the marsh birds, while marsh birds belonging to family Charadriidae are rare except the Eastern Golden Plover (Pluvialis dominica).The Large Egrets (Ardea alba) are abundant and thrive on benthic fauna.The Median Egret (Egretta intermedia), Pond Heron (Ardeola grayii), Cattle Egret (Bubulcus ibis), Temminck's Stint (Caladris temminckii) and Whitenecked Stork (Ciconia episcopus) were observed and recorded.As regards Whitenecked Stork only two individuals were observed in Sibia river during the survey.They are resident and locally migratory, and occur well-watered plains country, partial to water-logged ground and feeds on fishes, frogs, reptiles, crabs, molluscs and large insects etc.The Gulls and Terns belonging to the family Laridae prey mainly on fishes and allied aquatic forms.A good number of Blackbellied Tern (Sterna acuticauda) and Indian River Tern (Sterna aurantia) were abundant.The avian families associated with wetland were recorded such as Motacillidae and Alcedinidae.Among them the White Wagtail, (Motacila alba) were commonly found.The passerine and non-passerine birds represent a good number.But the Bengal Whitebacked The vulture was found to devour mainly on decaying bodies of the domestic animals inside the sanctuary.During the survey several such decaying bodies were noticed.The local herdsman informed that the enormous loss of livestock was caused by the consumption of Wild jujuba (Zizyphus jujuba).The Hoopoe (Upupa epops) under family Upupidae and the Bengal Florican, (Eupodotis bengalensis) under family Otidae are very rare in this sanctuary.During survey four Hoopoes and two Bengal Floricans were observed.The Bengal Florican which is an endemic Vulture (Gyps benghalensis) and Indian Griffon Vulture (Gyps fulvus) are drastically declining in population at this sanctuary as well as throughout India due to outbreak of disease, chemical contamination and poising (Vulture population decline in India-A Pilot survey by Robert B. Groubh, Director Institute for Restoration of Natural Environment, Nagercoil, Tamil Nadu, India and V. S. Vijayan, Director, Salim Ali Centre for Ornithology and Natural History, Coimbatore, Tamil N adu, India).
(Alfred & Chattopadhyay, 1995) of mammals and 123 species of birds) is less when compared to well known protected area like Manas Tiger Reserve, Assam (76 species of mammals and 300 species of birds videFauna of Conservation Area No.8: Fauna of Manas Tiger Reserve, 1995)and Namdapha Biosphere Reserve, Arunachal Pradesh (96 species of mammals and 233 species of birds vide Qualitative Analysis of Faunal Resources of proposed Namdapha Biosphere Reserve, Arunachal Pradesh,Ghose, 1987).It is also evident that D' Ering Memorial Wildlife Sanctuary is inhabited by comparatively less number of Schedule-l species of both mammals (6 species) and birds (8 species) under Wildlife (Protection) Act.1972.The Schedule-l species of mammals and birds of Manas Tiger Reserve, Assam; Balphakram Nationa Park, Meghalaya(Alfred & Chattopadhyay, 1995)and Namdapha