Behavioral indices of estrus in a group of captive African elephants (Loxodonta africana)
Abstract 10.1002/zoo.20053.abs This study investigated behavioral signals of estrus by systematically monitoring the interactions of one male with four female African elephants housed in a naturalistic outdoor enclosure at Disney’s Animal Kingdom over a period of 11 months. We measured changes in five spatial behaviors and 22 tactile-contact behaviors, as well as changes in serum […]
Nutritional composition of the diet of Alouatta palliata mexicana females in different reproductive states
Abstract 10.1002/(SICI)1098-2361(1999)18:63.3.CO;2-I Observational data on the feeding and behavior of a semi free-ranging troop of mantled howler monkeys (Alouatta palliata mexicana) were collected and analyzed to determine whether differences exist in the nutritional composition of the diet of females at different reproductive states. The reproductive states selected for study were non-gestation (control), gestation, and lactation. […]
Social and environmental factors affecting fecal glucocorticoids in wild, female white-faced capuchins (Cebus capucinus)
Abstract Assessing glucocorticoid levels in free-ranging nonhuman primates provides a means to determine the social and environmental stress load for individuals. We investigated the effect of four proximate variables—reproductive state, season, male rank stability, and dominance rank—on the level of fecal glucocorticoids (cortisol metabolites) in eight adult female white-faced capuchin monkeys in Costa Rica. Reproductive […]
Differential foraging strategies: motivation, perception and implementation in urban free-ranging dogs, Canis familiaris
Animals exhibit intraspecific variation in foraging behaviour when alternative strategies are likely to fetch greater returns for one individual over another. The mechanisms underlying such variation are often behavioural, physiological or ecological in nature. We studied intraspecific variation in foraging strategies and its possible causes in a population of urban free-ranging dogs by accounting for […]
The effect of energetic and psychosocial stressors on glucocorticoids in mantled howler monkeys (Alouatta palliata)
The proximate causes of variation in glucocorticoids (GCs) of many free-ranging primates are still unclear, and in some cases, the available evidence is contradictory. Such is the case of mantled howler monkeys. In the present study, we tested whether variation in GC levels in this species could be predicted by energetic challenges or by psychosocial […]
Male behaviours signal the female’s reproductive state in a pair of black rhinoceros housed at Lincoln Park Zoo
The black rhinoceros (rhino; Diceros bicornis) is a Critically Endangered species due to habitat loss and poaching. Zoological institutions’ breeding programs have been minimally successful over the years. Our goal was to introduce and breed an eastern black rhino (Diceros bicornis michaeli) pair at Lincoln Park Zoo (LPZ; Chicago, IL USA). The specific objectives were […]