Emotional states following grooming in female mandrills.

Grooming is a common cooperative behavior whose exact costs and benefits are still to be fully elucidated. In this study, we evaluated the emotional consequences of giving and receiving grooming in mandrills (Mandrillus sphinx), and how these may change along time after the termination of grooming. We used scratching as a behavioral indicator of anxiety-like emotions. Groomees showed increased scratching immediately after the termination of grooming, while in the subsequent minutes scratching decreased below baseline. The initial increase was larger after longer grooming events, suggesting it represented a case of postinhibitory rebound. The subsequent decline in scratching rates was larger after grooming received by a kin, suggesting interactions with kin are particularly relaxing. Scratching rates shown by groomers were unaffected by grooming interactions. These results highlight that the emotional states following grooming can have a complex time course, and may contribute to explain the inconsistencies found in the previous literature.

Precursors and aftermath of severe targeted aggression in captive cotton-top tamarins.

We observed a zoo-housed group of cotton-top tamarins (Saguinus oedipus) before and after a bout of severe targeted aggression directed towards two of its members. The aggression was so severe and repeated that the zoo personnel was forced to remove the two victims and the main aggressor. In the tense period that preceded removal, the tamarins showed increased aggression, a steeper and linear dominance hierarchy, and reduced post-conflict reconciliation compared to the period following removal. In contrast, affiliative interactions such as grooming and peaceful food transfers did not differ in the two periods of observations. Patterns of reciprocity also remained stable. These results highlight the flexibility of tamarin social relationships and provide useful information for managing captive colonies and improving animal welfare.

Feeding Enrichment in a Captive Pack of European Wolves (Canis Lupus Lupus): Assessing the Effects on Welfare and on a Zoo's Recreational, Educational and Conservational Role.

This study investigated the effects of two feeding enrichment programs on the behaviour of a captive pack of European wolves (Canis lupus lupus) and their correlation with both zoo visitors' interest towards the exhibit and their overall perception of the species. Behavioural data (exploration, stereotypies, social interactions, activity/inactivity rates) were collected on four male wolves during four two-week long phases: initial control, hidden food, novel object, final control. Three observation sessions were performed daily: before, during and after feeding. Number of visitors and their permanence in front of the exhibit were recorded. After watching the wolves, visitors were asked to fill out a brief questionnaire in order to investigate their perception of captive wolf welfare, as well as their attitude towards wolf conservation issues. Despite the high inter-individual variability in their behavioural response, all wolves seemed to benefit from feeding enrichment. With regard to visitors, interest in the exhibit increased when enrichment was provided. Visitors' perception of the level of welfare of wolves improved if they attended a feeding session, especially during the novel object phase. Visitors' attitude towards wolf conservation issues also improved during feeding sessions, regardless of enrichment provision.