Applied Animal Behaviour Science, 27 (1990) 169-176 Elsevier Science Publishers B.V., Amsterdam 169 Are alarming events good for captive monkeys? Arnold S. Chamove* and Eleanor M. Moodie Psychology Department, University of Stirling, Stirling FK9 4LA (Gt. Britain) (Accepted for publication 4 April 1990) ABSTRACT Chamove, A.S. and Moodie, E.M., 1990. Are alarming events good for captive monkeys? Appl. Anim. Behav. Sci., 27: 169-176. To evaluate a hypothesis suggesting that brief arousal may be beneficial to laboratory animals, 39 cotton-top tamarins living in four families were observed following stimulating husbandry proce- dures. Arousal led to an improvement in behaviour (i.e. decrease in activity and an in.crease in affili- ation) during the remainder of the day, changes similar to patterns reported as positive effects of enrichment but opposite to negative effects of long-term stressors; a wider range of normal behaviour; but we found no evidence for an improved response to challenge. INTRODUCTION Elsewhere we have argued that the goal of enrichment should be to provide conditions enabling animals to approximate the full range of normal behav- iour in captivity, and that the mechanism for this is to "increase psychologi- cal space" by providing natural stimuli, albeit in a modified form (Chamove and Anderson, 1989). We have suggested four criteria for "more normal" behaviour: ( 1 ) a reduction of abnormal behaviour; (2) an increase in the range or number of normal (i.e. wild) behaviour patterns; ( 3 ) behaviour pat- terns which are more normal in their temporal distribution during the day; (4) an ability to cope with challenges in a more normal way. While most animal welfare researchers advocate the reduction of stress, a few suggest that low-intensity arousal may be "adaptive", and presumably, as a consequence, healthy (Dantzer and Mormede, 1983; Ewbank, 1985 ). We feel that it is the duration of the arousal rather than its intensity that differ- entiates healthy from unhealthy arousal. Research results offer at least four sources of indirect support for the idea that arousal is beneficial, as long as it *Author to whom correspondence should be addressed at: Psychology Department, Massey University, Palmerston North, New Zealand. 0168-1591/90/$03.50 © 1990 -- Elsevier Science Publishers B.V.