By M. Jayashankar & Mahendra Devanda
Be it the mischievous chipmunk duo, the clever cum active Chip and carefree Dale or the chipmunks with Alvin in the Hollywood movie, members of the squirrel family present a lively and speedy character. Busy segregating faunal collections after our local survey to Lichi, near Potin in Lower Subansiri and a small break to gaze through the window from our first floor in the APRC/ZSI building at Senki valley, we observed a vivid movement in the papaya tree. A brown hairy squirrel was observed roving amidst a papaya bunch and shortly finished his surveillance to tooth in a ripe papaya with his incisors. It was the Hoary-bellied Himalayan Squirrel or Irrawady Squirrel, Callosciurus pygerythrus. The individuals measure 17-19 cm from head to tail tip and their dorsal hairs have two light rings of yellow, giving a hoary look.The species has a wide distribution ranging from northeastern South Asia, southern China and western Southeast Asia including Bangladesh, Bhutan, India, and Nepal constituting its endemic range.Its entire distribution lies west of the Mekong, and west of the Irrawaddy river in Myanmar, hence its common name the Irrawaddy Squirrel. It is a diurnal and arboreal rodent inhabiting thick to moderate evergreen forest patches and riverine habitats. It is also recorded from gardens, plantations, cane shrubs, edge and even degraded areas. Our sighting is an example of backyard surprises presented by nature for a biologist with the ability to observe nature, an inherent human skill.
The order rodentia (largest number of living mammal species) to which rats, squirrels, beavers and porcupines belong is derived from Latin ‘rodere’ meaning ‘to gnaw’. Enduring their constant gnawing squirrels have four incisors that grow continuously at a rate of about six inches per year!. During our observation the adult male was probing the papaya bunch to relish for the sunny afternoon in all postures allowing us to capture his images for more than fifteen minutes till he disappeared into the adjacent bamboo bush of the Nature Conservation Area behind APRC/ZSI building. The species is known to consume flowers, fruits, bark, seed, leaves, insects and lichen. With an annual reproduction cycle a litter size averaging three to four offspring these rodents exhibit parental care by constructing ‘dreys’ made of leafy twigs and branches housing a mother and the young ones. Squirrels are usually solitary and rarely group into scurries. Based on their spatial occupation squirrels are recognized as tree squirrels, ground squirrels and flying squirrels. Tree squirrels have long, bushy tails, sharp claws and large ears. Flying squirrels have a furred membrane ‘patagium’ extending between the wrist and ankle that allows them to glide between trees. Ground squirrels have short, sturdy forelimbs for digging and have fully furred tails. The Hoary-bellied, Orange-bellied and Pallas’s Squirrels are non-striped diurnal squirrels of the northeast region of India.
It is listed as a Least Concern species by IUCN (International Union for Conservation of Nature) but listed in the Schedule II of the Indian Wildlife (Protection) Act, 1972. Hunting and habitat loss due to encroachment of forest, shifting agriculture, small-scale and selective logging, clear cutting of forest, the establishment of human settlements, forest fires, and hunting for local consumption are major threats to the survival of the species.
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