Examination of the interrelationships of behavior, dominance status, and ovarian activity in captive Asian and African elephants
Abstract 10.1002/zoo.20025.abs Ovarian inactivity has been identified in captive African (Loxodonta africana) and Asian (Elephas maximus) elephants and is thought to be mediated in part by social influences. Thus, a survey was conducted to determine how behavior and dominance status relate to each other and to ovarian cyclicity. For both Asian and African elephants, dominance […]
Effect of noxious stimulation upon antipredator responses and dominance status in rainbow trout
A potentially painful experience may modify normal behavioural responses. To gauge the importance of pain relative to predation or social status, we presented competing stimuli, a predator cue or an unfamiliar social group, to two groups of noxiously treated rainbow trout, Oncorhynchus mykiss. In the predator cue experiment, fish were classified as bold or shy. […]
Linear social dominance hierarchy and corticosterone responses in male mallards and pintails
In winter, dabbling ducks gather in large flocks and males compete not only for food resources but also for mates. Setting up a social hierarchy is one way to reduce the costs of conflicts, but the position in the hierarchy has implications for individuals, for instance their susceptibility to conflict and interference, hence to social […]
Influence of indoor-cat group size and dominance rank on urinary cortisol levels
Domestic cats (Felis silvestris catus) are often housed indoors both singly and in groups. However, there is a lack of studies dealing with cat-cat relationships, group composition and effects of environmental parameters on the well-being of privately-owned cats. One way to index the effects of stressful situations is to measure glucocorticoid levels, as glucocorticoids are […]
Mate competition, testosterone and intersexual relationships in bonobos, Pan paniscus
Variation in male testosterone levels across and within species is known to be related to mating systems, male dominance rank and aggression rates. When aggression enhances access to mates, dominance status and androgen levels correlate positively. Deviation from this pattern is expected when access to females is determined by factors other than male dominance or […]
Social Correlates of Variation in Urinary Cortisol in Wild Male Bonobos (Pan paniscus)
Cortisol excretion in males of group living species is often associated with social rank and competition for oestrous females. Rank-related patterns of cortisol levels can be used to study mechanisms of rank maintenance and costs associated with mate competition. Bonobos (Pan paniscus) are interesting because males form a linear dominance hierarchy but are not dominant […]
Investigating temporary acyclicity in a captive group of Asian elephants (Elephas maximus): Relationship between management, adrenal activity and social factors
Routine faecal steroid monitoring has been used to aid the management of five captive Asian elephant (Elephas maximus) females at Chester Zoo, UK, since 2007. Progestagen analysis initially revealed synchronised oestrous cycles among all females. However, a 14- to 20-week period of temporary acyclicity subsequently occurred in three females, following several management changes (increased training, […]