Functional Analysis and Successful Treatment of a Captive Rhesus Macaque's Disruptive Behavior.

Functional analysis (FA) is a method developed and used by behavior analysts in human clinical settings to identify possible environmental variables that reinforce undesired behavior. FA is increasingly being applied to better understand the behavior of nonhuman animals. When training monkeys in a room with others, disruptive behavior displayed by neighboring monkeys can impede training progress. In the present study, a FA identified possible reinforcers of disruptive behavior (loud shaking of a toy) exhibited frequently (24% duration pre-treatment) by a rhesus macaque (Macaca mulatta) during in-room training sessions. The functional analysis identified that contingent delivery of foods was maintaining the disruptive behavior, with a mean percent duration of 57% in this condition. The implementation of a function-based treatment consisting of continuous access to a preferred food during in-room training sessions successfully decreased disruptive behavior by over 90% as measured during 15 subsequent sessions. This study advances the current literature applying functional analysis to nonhuman primates as a means of determining the reinforcers maintaining aberrant or undesirable behavior and applying effective treatments based on understanding this function.

Survey of Behavioral Indices of Welfare in Research Chimpanzees (Pan troglodytes) in the United States.

Chimpanzees demand specialized housing and care and the highest degree of attention to animal welfare. The current project used a survey method to collate information on chimpanzee housing and behavioral indices of welfare across all 6 of the chimpanzee research facilities in the United States. Data were compiled on 701 chimpanzees ranging from 2 to 62 y old (mean age, 26.0 y). All chimpanzees except for one were socially housed; the median group size was 7 animals, and group sizes ranged from 1 to 14. All of the subjects had access to outdoor spaces each day. Daily access to a natural substrate in the chimpanzee's enclosure was available for 63.8% of the subjects. Overall, 94.1% of the chimpanzees used tools to acquire food, 48.1% built nests, 75.8% copulated, and 83.3% initiated grooming bouts. The following atypical behaviors were reported most often: rocking (13.0%), coprophagy (10.0%), and stereotyped behaviors other than rocking (9.4%). There was widespread evi- dence of positive animal training techniques, with nearly all (97.7%) subjects reported to generally voluntarily cooperate with shifting in their enclosure, and 72.2% were reported to present for an injection of anesthetic. We include some comparison between these findings and data describing zoo-housed chimpanzees. In addition, we discuss survey findings in reference to recommendations made by the NIH Working Group on the Use of Chimpanzees in NIH-supported Research. The current survey assessed a larger sample of chimpanzees living under human care than has been published previously. This broad analysis can help to guide future improvements in behavioral management to address behavioral problems or deficits.

Systematic assessment of food item preference and reinforcer effectiveness: Enhancements in training laboratory-housed rhesus macaques.

The use of systematic preference assessments can enhance positive reinforcement training with captive animals. We found that the multiple stimulus without replacement (MSWO) technique identified food preferences in laboratory housed rhesus macaques, with raisins and grapes being ranked higher on average than dried apricot, pasta, and green beans (Friedman Test, χ2 (4) = 35.52, p < .001). Agreement between individuals (N = 21) was moderate (Kendall's W = 0.42), and consistency across time varied among individuals (W = .03-.90). Highly preferred items identified by the MSWO assessment were subsequently found to increase subjects' engagement in a husbandry task on which they were being trained (Mann-Whitney U = 6.00, p = .002) and to improve performance on a progressive ratio schedule (Wilcoxon signed-rank test, Z = -2.17, p = .03) when compared with low preference items. The progressive ratio technique supplements other preference assessment techniques by measuring the amount of work a subject will do to gain access to an item. The use of more effective reinforcers identified through systematic assessment has the potential to increase animal performance on husbandry and research tasks and to improve animal welfare in the laboratory setting.