Responses of diurnal tree squirrels to selective logging in western Arunachal Pradesh.

The responses of diurnal tree squirrels to logging were determined by comparing their abundance in recently logged forest, 20-25-yr-old logged forest, unlogged primary forest, a relatively disturbed secondary forest and a plantation in western Arunachal Pradesh. The squirrels recorded were the Himalayan striped squirrel (Tamiops macclellandi), hoary-bellied squirrel (Callosciurus pygerythrus), red-bellied squirrel (Callosciurus erythraeus) and the Malayan giant squirrel (Ratufa bicolor). The generalist hoary-bellied squirrel was the most common species overall. Its abundance was highest in logged forest and plantations that are characterized by low canopy cover and reduced tree density. It was the only species recorded in the plantations. The other three species were most abundant in unlogged forest. The abundance of the more arboreal Malayan giant squirrel and red-bellied squirrel was correlated to higher tree density and canopy cover, which are characteristic of unlogged primary forests. The reduced canopy cover, tree density and basal area in logged forest, and low tree species diversity and structural complexity in plantations lead to reduction or total absence of squirrels in these habitats. Degree of arboreality, diet and nesting requirements play an important role in squirrel abundance, with largersized or specialist species being more vulnerable to habitat modification due to logging. [ABSTRACT FROM AUTHOR]