Sulawesi giant squirrel  (Rubrisciurus rubriventer)

The Sulawesi giant squirrel is classified as Vulnerable (VU) on the IUCN Red List (1).

The Sulawesi giant squirrel (Rubrisciurus rubriventer) is so-named as it is the largest of the eight tree squirrel species found in Sulawesi (2). The Sulawesi giant squirrel has rich reddish fur on its underparts, limbs, feet and shoulders, and longer brownish fur on its head and back, which is speckled with buff, black and orange. Its ears are highlighted by glossy black tufts and there is a dark crescent above each eye. The bushy tail of the Sulawesi giant squirrel is reddish-brown (2).

Juvenile Sulawesi giant squirrels differ from adults in having thinner, shorter fur and duller colouration (2).

The Sulawesi giant squirrel occurs on Sulawesi in Indonesia, and just north of Sulawesi on the island of Sangihe (1).

Although primarily an inhabitant of tropical lowland evergreen rainforest, the Sulawesi giant squirrel is alsofound at altitudes where tropical lower montane rainforest dominates (2).

The Sulawesi giant squirrel is active during the daytime, when it travels and forages in the forest understorey and on the ground (2). The varied diet of the Sulawesi giant squirrel comprisesfruits, such as figs and fruit from the pohon dongi (Dillenia serrate) and seeds, such as those of the pohon pangi (Pangium edule) plant. The Sulawesi giant squirrel also feeds on insects, such as termites and beetle larvae, which are picked off leaf litter and tree trunks or dug out from rotting wood (2).

The fruit of Pangium edule is large and woody and contains large, hard seeds. Often the sound of the squirrel gnawing on tough seeds such as this are the only indicator of this quiet and wary squirrel’s presence (2). An easily startled animal, the Sulawesi giant squirrel is often just seen as reddish streak disappearing into the forest undergrowth (2).

The nest of the Sulawesi giant squirrel is a large, globular structure, measuring about 30 centimetres in diameter. The nest is constructed from the long, black sturdy fibres of the sugar palm (Arenga pinnata) and is typically placed in the cavity of a large tree trunk, not far from the ground (2). Little else is known about the breeding biology of this elusive animal.

Numbers of the Sulawesi giant squirrel are thought to be declining, primarily as a result of human activities. Rapid and large-scale deforestation on Sulawesi for logging and agricultural purposes, especially in lowland areas, has destroyed much of the squirrel’s habitat (1).

Small-scale hunting has also had an impact on Sulawesi giant squirrel numbers (1).

The Sulawesi giant squirrel occurs in at least two protected areas (1), which may offer its forest habitat some degree of protection. However, no specific conservation measures are currently known to be in place for this endangered rodent.

Learn about conservation in Sulawesi:

• Wildlife Conservation Society:
  http://www.wcsip.org/saving-wild-lands/sulawesi