Should Zoo Food Be Chopped for Captive Turacos?

It is common practice for keepers in zoological collections to provide animals in their care with food that is chopped into small pieces. Anecdotally, it has been suggested that chopped food reduces wastage and reduces aggression from group-housed animals. However, there is limited empirical evidence to support these suggestions. To investigate the effects of food condition (chopped or whole food), a study was undertaken on White-cheeked Turacos (Tauraco leucotis) and Fischer’s Turacos (Tauraco fischeri) at two zoological collections in the United Kingdom. This study investigated the effect of food condition on turaco behaviour, the amount of food eaten, and also the amount of time that keepers required to prepare the diet. There was no significant impact on the amount of food eaten as a result of providing whole food. For Fischer’s Turacos, the whole-food condition significantly increased the prevalence of feeding and foraging behaviour, whilst significantly reducing preening. For White-cheeked Turacos, only feeding and foraging was affected by food condition: no other behaviours were significantly affected by chopped or whole food. Keepers on average saved 151 s per meal when preparing whole-food diets. Overall, this study suggests that changing food presentation from chopped to whole has a limited impact on food intake and behaviour. Providing whole-food items may also save valuable keeper time. Future studies should investigate the impact of feeding whole-food items to a wider range of zoo-housed species.

Gibbon strategies in a food competition task

Social primates face conflicts of interest with other partners when their individual and collective interests collide. Despite living in small, primarily bonded, groups compared to other social primates, gibbons are not exempt from these conflicts in their everyday lives. In the current task, we asked whether dyads of gibbons would solve a conflict of interest over food rewards. We presented dyads of gibbons with a situation in which they could decide whether to take an active role and pull a handle to release food rewards at a distance or take a passive role and avoid action. In this situation, the passive partner could take an advantageous position to obtain the rewards over the active partner. Gibbons participated in three conditions: a control condition with no food rewards, a test condition with indirect food rewards and a test condition with direct food rewards. In both test conditions, five rewards were released at a distance from the handle. In addition, the active individual could obtain one extra food reward from the handle in the direct food condition. We found that gibbons acted more often in the two conditions involving food rewards, and waited longer in the indirect compared to the direct food condition, thus suggesting that they understood the task contingencies. Surprisingly, we found that in a majority of dyads, individuals in the active role obtained most of the payoff compared to individuals in the passive role in both food conditions. Furthermore, in some occasions individuals in the active role did not approach the location where the food was released. These results suggest that while gibbons may strategize to maximize benefits in a competitive food task, they often allowed their partners to obtain better rewards. Our results highlight the importance of social tolerance and motivation as drivers promoting cooperation in these species.

Feeding Behavior of Mice under Different Food Allocation Regimens

Social interaction, a basic survival strategy for many animal species, helps maintain a social environment that has limited conflict. Social dominance has a dramatic effect on motivation. Recent evidence suggests that some primate and nonprimate species display aversive behavior toward food allocation regimens that differ from their peers. Thus, we examined the behaviors displayed by mice under different food allocation regimens. We analyzed changes in food intake using several parameters. In the same food condition, the mice received the same food; in the quality different condition, the mice received different foods; in the quantity different condition, one mouse did not receive food; and in the no food condition, none of the mice received food. To test differences based on food quality, one mouse received normal solid food as a less preferred reward, and the other received chocolate chips as a high-level reward. No behavioral change was observed in comparison to the same food condition. To test differences based on food quantity, one mouse received chocolate chips while the other received nothing. Mice who received nothing spent more time on the other side of the reward throughout the experiment. Interestingly, highly rewarded mice required more time to consume the chocolate chips. Thus, under different food allocation regimens, mice changed their behavior by being more hesitant. Moreover, mice alter food intake behavior according to the social environment. The findings help elucidate potential evolutionary aspects that help maintain social cohesion while providing insights into potential mechanisms underlying socially anxious behavior.