50 Sciurus deppeiberries. It appears to function predominantly as a seed pred-
ator, although studies on scatter-hoarding and seed disper-
sal are generally lacking. It has been reported to possibly aid
in the fi rst stage of a two-stage dispersal process of Guarea
glabra and G. kunthiana in Costa Rica by removing the arils
of their seeds and then dropping them below the parent
trees, where they may be further dispersed and cached by
other rodents. At least one study, however, reports a limited
consumption of leaves, and others note the use of fungi and
insects. This species is also known to damage crops (e.g.,
corn/maize). S. deppei is diurnal and shows a bimodal pat-
tern of activity, with peaks in early morning and just before
sunset. It is frequently observed foraging on the ground, of-
ten in dense vegetation; yet this species is arboreal and re-
lies on both cavities and dreys (made of leaves and twigs) for
nesting. It is agile and moves easily through all parts of the
arboreal habitat. While Deppe’s squirrel is not considered
social, it is often observed in small groups. It is reported to
vocalize under some circumstances, although it is also con-
sidered secretive. This species’ vocalizations are reported to
be high-pitched trills that are often accompanied by rapid
tail fl icks. Based on anecdotal observations of lactating fe-
males, embryos, and nestlings, it appears that reproduction
in this species can occur throughout the year, but at least
one author reports that reproduction happens most often at
the end of the dry season. Litter sizes range from two to
eight, and average about four. At least two subspecies of S.
deppei have three pairs of functional mammae, instead of
four as in all other species of Sciurus. Densities have been
reported as low as 2.2 and as high as 100 animals/km^2. Esti-
mates of home range size average 1.5 ha.
This species appears to be relatively tolerant of human
activity. In a study in Guatemala that compared mammal
and bird densities in sites heavily visited by tourists and in
control sites, S. deppei was one species showing higher den-
sities in tourist sites (32.3/km^2 versus 2.2/km^2 in tourist ver-
sus control sites). This species is hunted and sold for food in
relatively low numbers in markets in Chiapas (México). The
range of Deppe’s squirrel overlaps wit h t hat of S. aureogaster,
although these two species seem to show signs of micro-
habitat segregation. It is also occasionally found in the same
forests with S. variegatoides and S. yucatanensis. Compared
with all three of these species, S. deppei spends more time on
the ground, perhaps because it resides in more dense vegeta-
tion. Only ectoparasites have been reported from S. deppei.
These include one tick, (Ixodes tamaulipas), one chigger (Eu-
trombicula alfreddugesi), two lice (Enderleinellus deppei and E.
extremus), and four fl eas (Kohlsia graphis, Orchopeas howardi,
Plusaetis dolens, and Tr i c h o p s yl l a g r a p hi s).
general references: Barragán et al. 2007; Best 1995c;
Eckerlin 2005; Guzmán-Cornejo et al. 2007; Hidinger 1996;
Koprowski, Roth, Woodman, et al. 2008; Sánchez-Cordero
and Martínez-Gallardo 1998; Wenny 1999.Sciurus fl ammifer (Thomas, 1904)
Fiery Squirreldescription: The pelage of fi ery squirrels is variable, with
complete melanism as well as partial albinism documented.Sciurus deppei. Photo courtesy Tracey Dixon, http://www.trp.dundee
.ac.uk/~bl/.