62 Sciurus nigeroften at fi rst light, or—in low-density populations—they
may sleep in the female’s nest the night prior to estrus. Up
to 11 males will pursue a female during her mating bout.
Dominant males are able to mate by pursuing the female;
however, lower-ranking males, typically young individuals,
are able to copulate by waiting on the periphery of the bout
and tracking the female when she evades the aggression of
dominant males. Copulation lasts less than 30 seconds. A
copulatory plug forms within the female from the coagula-
tion of semen. Females will remove the plugs and mate with
several males. After a gestation of 44 or 45 days, a litter av-
eraging two to three (maximum of seven) young is born in a
tree cavity or leaf nest. Leaf nests are large spherical struc-
tures constructed in the canopy using twigs and leaves,
with a central nest chamber often lined with shredded bark
and leaves. A few females produce two litters in a year; adult
females typically produce a single litter each year. The young
emerge after 6–8 weeks, and weaning is not completed un-Sciurus niger shermani. Photo courtesy Bo Chambers.