DUSK CALLING IN BARBARY MACAQUES (MACACA-SYLVANUS) - DEMAND FOR SOCIAL SHELTER

Barbary macaques (Macaca sylvanus) show an increase in vocal activity at dusk. This investigation showed that these vocalizations were mainl y produced by juveniles from six to 18 months of age, during their att empts to achieve body contact with their mothers, thereby building up a sleeping cluster. The ''dusk calling'' consisted of protracted seque nces of variable vocal patterns which always ceased when the juvenile joined its preferred sleeping cluster. The length of the sequences cor responded to the time it took the juvenile to be accepted into a sleep ing cluster. One-year-old juveniles exhibited the highest vocal activi ty. The similarity of the results obtained in two outdoor enclosures i n France and of those in the field (Morocco) indicated that dusk calli ng is common to this species, and not a behavior unique to captive ani mals. (C) 1994 Wiley-Liss, Inc.