Role of Sound Communication in Mating of Malaysian Callosciurus (Sciuridae)

Abstract

Mating behavior was compared between two species of tree squirrels, Callosciurus caniceps and C. notatus , in Ulu Gombak, Selangor Darul Ehsan, Malaysia. In the mating bouts of C. caniceps , six to eight males assembled within the home range of an estrous female early in the morning. The female mated with four to six males during mating bouts of ca. 6 h. Each male produced a barking sound for 12–35 min after copulation, during which time the female and the other males stopped moving. The other males frequently gave precopulatory calls and waited for a chance to mate when the mating males departed. In C. notatus , five to seven males assembled near an estrous female and two to four of them mated during 6–7 h of a mating bout. The postcopulatory barks continued for only 0.5–8.0 min. The precopulatory calls were low amplitude and were given infrequently. Chasing among males was observed repeatedly near the female. Males had to guard the female against frequent challenges by other males. C. caniceps predominated in a bushy area and more subtly used auditory communication in mating than did C. notatus in open forests.