Squirrels of the World

Heliosciurus undulatus 231

rather than in the higher canopy. They build open nests of
grass and leaves in the crooks of branches or vegetation.
These squirrels are primarily vegetarian but occasionally
consume insects, and they may hoard food items. They for-
age on the stems and leaves of several species, most notably
various trees (Parinari holstii, Syzygium cordatum, Conophar-
yngia holstii, Carapa, and Urera hypselodendron), and the li-
chen Usnea. Ruwenzori sun squirrels are quite opportunistic
in farmlands and plantations, feeding on guavas, papayas,
bananas, and palm nuts when available. Little information
is available about the social or reproductive structure of this
species. Individuals usually remain solitary or socialize in
pairs. One pregnant female was found in March with three
large young, indicating that females may come into estrous
and mate again before the previous litter is weaned and in-
dependent. They most commonly vocalize to others with a
loud “chattering” call. As an individual moves through the
trees, it holds its tail horizontally out behind it, parallel to
the substrate.

general references: Kingdon 1974; Rahm and Christi-
aensen 1963; Thomas 1909.

Heliosciurus undulatus (True, 1892)

Zanj Sun Squirrel

description: The Zanj sun squirrel is a large animal, char-
acterized by its brown gray dorsal pelage and long thin tail

ringed with 10–14 alternating black and pale bands. The ven-

tral coat ranges from light gray to ochre. The color of the

face, nose, and feet is similar to that of the dorsal pelage,

with highlights of light gray to orange ochre. The intensity

of coloration on the dorsal pelage varies geographically,

with squirrels from higher elevations being darker and

richer in color, animals to the north paler, and individuals

from the south duller and grayer.

size: Female—HB 235.3 mm (n = 4); T 270.0 mm (n = 4).

Male—HB 241.1 mm (n = 4); T 261.9 mm (n = 7).

Sex not stated—HB 232.2 mm (n = 20); T 277.4 mm (n =

20); Mass 315.0 g (n = 2).

distribution: This species is found in southeastern Kenya

and northeastern Tanzania, as well as on the Tanzanian is-

lands of Pemba, Zanzibar, and Mafi a.

Heliosciurus undulatus. Photo courtesy William T. Stanley.