Spatial Design of Guest Feeding Programs and Their Effects on Giraffe Participation and Social Interactions.

Guest-animal feeding programs (GFPs) in zoological institutions aim to foster human-animal connections. The growing establishment of animal welfare science emphasizes the assessment of GFPs as permanent environmental inputs to habitats that require analysis of behavioral output. This study assessed the role of space allocation on giraffe participation and interactions in GFPs in two Florida zoos.Analysis of social structure indicates that centrality and influence from affiliative network on exhibit shape sharing interactions at GFPs under varying management protocols and designs. Findings suggest that interactions and significant ties among conspecifics are context and potentially temporally dependent. We propose the use of multiple guest engagement stations to maximize space and facilitate feeding opportunities for central and peripheral members. This proposed shift would provide variable feeding opportunities that represent group composition following ecological theory while maximizing points of guest engagement. Results indicate that increasing space allocation for GFPs increased feeding bout length for individuals, percent of time sharing among conspecifics, and reduced average rate of displacement/minute. Cross-institutional comparisons indicate that guest programs with more space allocation have lower rates of conspecific displacement.

Mechanisms underlying maternal care in a viviparous snake, Sistrurus miliarius: Does maternal body condition, corticosterone, or arginine vasotocin mediate post-birth maternal investment?

The level of parental investment in free-living offspring varies greatly within and among vertebrate taxa, and the mechanisms that mediate investment are likely targets of selection in the evolution of reproductive strategies. In mammalian and avian systems, individual investment is adjusted according to parental energetic status, and regulatory mechanisms have been described. Parental care is also a component of the life history of several groups of squamates and archosaurs, but little to nothing is known regarding the mechanisms that underlie individual variation in parental investment in these groups. Therefore, we examined the relationships among maternal body condition, corticosterone, arginine vasotocin (AVT), and maternal care in postparturient pigmy rattlesnakes. Energetic status was manipulated in pregnant females by supplemental feeding, and AVT was manipulated in postparturient mothers by intraperitoneal injection. Circulating corticosterone and body condition were recorded in postparturient mothers. Mother-offspring spatial relationships were analyzed to determine the closeness of mother-offspring associations. No significant relationship between maternal body condition and baseline corticosterone was observed in mothers, and no significant relationship was found between corticosterone and the level of maternal association with offspring. Manipulation of AVT did not stimulate maternal care. There was a strong and repeatable positive relationship between maternal postparturient body condition and the level of maternal association with offspring. The lack of a significant correlation between body condition and corticosterone does not support the hypothesis that a postparturient glucocorticoid response drives the observed condition-dependence of maternal offspring association.