The developmental origin of abnormal behaviors is generally associated with early rearing environments that lack sufficient physical and sensory stimulation. However, other factors should also be considered. A large sample of captive chimpanzees (128 males and 140 females) was surveyed for the presence or absence of 18 abnormal behaviors. Origin variables included the subject's source (zoo, pet, performer, or laboratory), rearing (mother-or hand-reared), and sex. Animals were assessed while held at the Primate Foundation of Arizona, University of Texas M. D. Anderson Cancer Center, or White Sands Research Center. There was a confound among origin variables; more hand-reared animals than expected were from laboratories. Logistic regression tested the relationship of rearing and source, with sex as a secondary predictor variable, to each of the abnormal behaviors. There was no clear association between any abnormal behavior and source. However, for coprophagy, relative to animals from the laboratory, zoo animals tended to show a higher prevalence, while performers tended to show a lower prevalence (when rearing and sex were controlled). Rocking and self-sucking were significantly more likely in hand-reared animals. Coprophagy and depilation of self were significantly more likely in mother-reared animals. When rearing and source were statistically controlled, the only significant sex difference was a higher prevalence of coprophagy in females and a higher prevalence of rocking in males. In a second, smaller sample of 25 males and 33 females from Southwest Foundation for Biomedical Research, no significant sex association was found for coprophagy, urophagy, rocking, or self-depilation. In this second sample, coprophagy was also significantly more likely in mother-reared than hand-reared subjects. The association of some abnormal behaviors with mother-rearing suggests that some form of social learning may be involved in the origin of some of these behavior patterns. This indicates that some abnormal behaviors may not be always be indicative of reduced psychological well-being in captive chimpanzees. Am.

Mortality statistics from three captive populations of chimpanzees (Pan troglodytes) were combined to generate standard model life tables for each sex in this species. The model is compared to an estimate of survivorship of a group of wild animals, and is applied to an incomplete data set to illustrate how the model may be used t o extend estimates of mortality statistics to missing older ages. o 1995 Wiley-Liss, Inc.

An analysis of a feeding enrichment program for captive chimpanzees was completed to determine the effects of that program on the incidence of agonistic and abnormal behaviors by using 41 adult chimpanzees in six social groups. Four feeding enrichment procedures were implemented simultaneously in the experimental phase of this ABA design study. The procedures were planned to elicit time-consuming, noncompetitive feeding, theorizing a consequent reduction in agonism and detrimental abnormal behaviors typically occurring in captive chimpanzees. The 270 hours of data were collected over a 6-month period. A multivariate analysis of variance result supported the hypothesis, as the barrage of feeding enrichment techniques significantly reduced agonism and abnormal behaviors. This study's significance lies in its application of the scientific method to improving the husbandry of captive primates.Key words: husbandry, abnormal behavior, aggression, psychological well-being INTRODUCTIONHusbandry practices as tools for the management of nonhuman primates have been little studied by primatologists [Maple, 19801. Husbandry routines can be treated as independent variables with their behavioral consequences measured as dependent variables. In this fashion, improvements in management routines can be objectively identified as their behavioral effects are quantified. The work of primatologists in attempting to improve primate husbandry is especially important in the current climate of increased concern over laboratory animal welfare.Some feeding regimens in captive chimpanzee colonies, and provisioning of wild chimpanzees, are generally acknowledged to contribute to excessive agonism [Fritz & Fritz, 1979; Goodall, 1986; van Hooff, 1967 van Hooff, , 1973Wilson & Wilson, 1968; Wrangham, 19741. Fights are triggered in competition for especially desirable foods or for food items that are defensible, and apparently increased fighting occurs in the high arousal state preceding an anticipated feeding. Short feeding duration and lack of variety in the captive chimpanzee diet, among other characteristics of captive feeding routines, almost certainly contribute to chimpanzees' development and expression of numerous pathologic behaviors, particularly those in which a major component is orality, such as self-mutilation, coprophagy, repeated regurgitation, excessive grooming, and urophagy.Although feeding practices have been recognized as a factor contributing to aggression and abnormal behavior in captive chimpanzee colonies, management decisions concerning feeding regimens have often been made without the benefit of relevant research [deWaal & Hoekstra, 1980; Fritz & Fritz, 19791. No controlled tests of changes in captive chimpanzee feeding regimens have been published. In the relatively small body of literature evaluating the effects of feeding enrichment procedures for nonhuman primates, most studies had small sample sizes, and several were conducted over durations as short as a few days. However, within these restrictions, feeding tec...

The purpose of this paper is to establish a vocabulary for the systematic documentation of abnormal behavior in restrictively reared chimpanzees. Such a vocabulary facilitates communication regarding the range of behavior patterns indicative of psychopathology. The behavior of restrictively reared chimpanzees was observed and descriptive statistics on abnormal behaviors are presented. Succinct descriptive terminology is developed to aid in documentation of the range of abnormal behavior observed in restrictively reared chimpanzees. Such documentation is the first step in monitoring and evaluating a rehabili t at ion program.

The effects of human and nonhuman primate interactions on the well-being of captive nonhuman primates have been studied less rigorously than other forms of environmental improvement. Human intervention might be used to moderate severe aggression of socially housed animals at feeding times, one of the most common behavioral management problems. In this study, positive reinforcement training techniques were applied to reduce a dominant male chimpanzee's aggression and chasing during meals. Verbal commands and food reinforcers were used to train him to sit and remain seated while other group members received and ate their share of produce. Observational data were collected recording all instances of agonism in the group during periods when meals were fed and during times when no meals were offered, both before and after the training was accomplished. Multivariate analysis of variance for repeated measures results indicated that the training program successfully reduced the group's incidence of displaying, submission, and aggression during feeding periods. This effect was specific to the times meals were fed; there was no generalized reduction in the group's agonism after the training. This study exemplifies the use of positive reinforcement techniques to modify chimpanzee social dynamics during a problematic situation and of observational data to evaluate quantitatively the behavioral effects of the training. Training can be employed to help solve behavioral management problems among socially housed animals, and it can help improve the psychological wellbeing of captive chimpanzees. o