IN323
Mahananda Wildlife Sanctuary


Site description (2004 baseline):

Site location and context
The Mahananda Sanctuary is located on the west bank of River Teesta in the southern part of Darjeeling district in West Bengal. It was declared a sanctuary in 1976 to protect the lower catchment of the Mahanadi river, but till 1988 it was under the control of the Kurseong Forest Division, when it was transferred to the Wild Life Division. The terrain is undulating, with moderate to steep slopes and high ridges towards the north. The hill slopes descend to almost flat stretches of the terai, and alluvial plains towards the south of the IBA. The main entry point of Mahananda WLS is via Sukna, a small village 12 km from Siliguri on the Siliguri-Darjeeling road. National Highway 31 passes through the southern part of the Sanctuary. It is perhaps the largest compact block of forested habitat situated at the western end of the migratory route of the Asian Elephant Elephas maximus. A large waterbody of nearly 1,500 ha, formed after the construction of a barrage on the Teesta, falls in the buffer zone of this Sanctuary. As Mahananda extends across hills as well as plains, the forest types are quite varied. In the hills we see Sal Forest, Dry Mixed Forest and Wet Mixed Forest. In some portions, Sal Shorea robusta forms almost pure stands, with an occasional other species such as Gmelina arborea, Terminalia, Lagerstroemia parviflora, Sterculia villosa and Toona ciliata. The flood plains of rivers are covered with Phragmites karka and Saccharum munja, with scattered Bombax ceiba trees. This habitat is under human pressure and only a few undisturbed patches are left. This is the habitat of Jerdon’s Babbler Chrysomma altirostre and the Bengal Florican Houbaropsis bengalensis. While the former is still reported occasionally, the latter species is probably extinct in this area.

Key biodiversity

AVIFAUNA: The bird life is very rich in Mahananda as the Park is at the crossroads of two biomes i.e. Sino-Himalayan Subtropical Forest and Indo-Chinese Tropical Moist Forests, with a small portion of Indo-Gangetic Plain. The higher reaches of the Park harbour elements of Sino-Himalayan Temperate Forest. The checklist prepared by Lobo (2003) has 316 species while in the Calcutta Gazetteer, (Anon. undated), 300 birds have been listed. The site lies in the Eastern Himalayas Endemic Bird Area (EBA 130) in which Stattersfield et al. (1998) have listed 21 species found in India. Only one has been located in this site, Rusty-bellied Shortwing Brachypteryx hyperythra, a bird of forest undergrowth and thickets (Grimmett et al. 1998). Interestingly, another rare and endemic bird found here is the Black-breasted Parrotbill Paradoxornis flavirostris, belonging to Assam Plains Endemic Bird Area (EBA 131) where only three species are considered restricted range, and Parrotbill is one of them. This bird is confined to tall, wet grasslands and reedbeds. There are unconfirmed reports of occurrence of Bengal Florican Houbaropsis bengalensis in the grasslands on the riverbanks. During surveys in the 1980s by Rahmani et al. (1990), this bustard was not located in Mahananda. There is a grassland called Ghoramora and on the River Teesta, about 1 km from Ghoramora there are some big grass-covered islands which could have some floricans. Another globally threatened species occurring here is the Rufousnecked Hornbill Aceros nipalensis. It is also reported in two more IBAs in West Bengal, Buxa and Lava-Neora. Mahananda WLS also has five Near Threatened species. Two biomes occur in Mahananda: Biome-8 (Sino Himalayan Subtropical Forest) from c. 1,000 to 1,800 m, and Biome-9 (Indo- Chinese Tropical Moist Forests) found below 1,000 m. BirdLife International (undated) has listed 95 species in Biome-8 that occur in India, out of which 20 species are found in this IBA. Similarly, many species of Biome-9 are also found. In winter, many birds of Biome-5 (Eurasian High Montane-Alpine and Tibetan) are seen here when they come down to escape winter. One of the most interesting species is Ibisbill Ibidorhyncha struthersii. Himalayan Griffon Gyps himalayensis is also seen sometimes, especially in the higher reaches of Mahananda.

OTHER KEY FAUNA: Besides the Asian Elephant Elephas maximus, Mahananda has its usual complements of large mammals such as the Tiger Panthera tigris, and Leopard P. pardus. Serow Nemorhaedus sumatraensis is present in Chawa, Andhera and Upper Ghoramara forest blocks, where occasionally Asiatic Black Bear Ursus thibetanus is sighted.

In the Moist Deciduous Forest on lower reaches, Gaur Bos frontalis is quite common, especially in Sevoke and Laltong blocks. Chital or Spotted Deer Axis axis, otherwise uncommon in north West Bengal, are common in Sevoke block and plantation areas, while Sambar Cervus unicolor is more widespread and found in all parts of the Sanctuary. A species worth mentioning is the Clouded Leopard Neofelis nebulosa, a feline seldom seen but likely to be present in this area as the habitat is suitable. Among the primates, five Hoolock Gibbon Hylobates hoolock were introduced in 1965, but they died out (Anon. undated).

Pressure/threats to key biodiversity
MAIN THREATS: Poaching; Illegal felling of trees; Agricultural intensification; Forest fires; Grazing; Logging; Road and rail transport.

Charaching is a serious problem, mainly due to the fact that the Sanctuary is easily accessible in the southern part. National Highway-31 passes through the Sanctuary, and there are numerous villages. Timber smuggling to provide raw material to numerous saw mills in nearby Siliguri town is another problem which the authorities face all the time. Grazing, a persistent problem of all sanctuaries in India, is quite severe here also. A large number of cows can be seen on the roads going towards the Sanctuary. During summer, villagers set fires to promote fresh growth of grass. This coincides with the breeding season of many ground-nesting birds (pheasants, quails, francolins, larks) and does obvious damage. There is a plan to widen the National Highway into an eight lane road. The Indian Railway plans to convert the existing metre-gauge track between Siliguri and Guwahati to broad-gauge, and also increase the frequency of trains. This would also affect the Sanctuary adversely.

Acknowledgements
Key contributor: Peter Lobo.


Recommended citation
BirdLife International (2024) Important Bird Area factsheet: Mahananda Wildlife Sanctuary (India). Downloaded from https://datazone.birdlife.org/site/factsheet/mahananda-wildlife-sanctuary-iba-india on 23/12/2024.