PROTECTIVE AND TERRITORIAL BEHAVIOR IN CAPTIVE SIAMANGS (HYLOBATES SYNDACTYLUS)

Protective and territorial behavior was observed in 14 heterosexual pa irs of adult siamangs in 11 zoos for a total of 1,155 h. The study sho ws that the quality of protective and territorial behavioral patterns was similar in the wild and in captivity. Under zoo conditions, the be havioral response (except calling) to conspecific and human rivals was similar. Males could be found more often at the front of the enclosur e and were more active in protective and territorial behavior than wer e females. Males were more attentive to happenings outside their enclo sures than were their mates, whereas females concentrated their protec tive and territorial activities on specific people or females of a con specific group. Although the duration of each song and the average num ber of duet sequences as well as the temporal distribution of calling throughout the day were similar in the wild and in the zoo, the total duetting rate differed remarkably: it was much higher in captivity. Si amangs in acoustical and visual contact with neighboring conspecifics spent more time singing than did siamangs without such contacts. In ca ptivity, pairs without young seemed to be more engaged in protective a nd territorial behavior patterns than were parents. (C) 1997 Wiley-Lis s, Inc.