Measuring Faecal Epi-Androsterone as an Indicator of Gonadal Activity in Spotted Hyenas (Crocuta crocuta)

The significant impact of extant carnivores, particularly spotted hyenas, on the depositional history and physical characteristics of archaeofaunal and paleontological assemblages is well recognized. We focus on the behavioral ecology of extant spotted hyenas (Crocuta crocuta) in relation to bone accumulations produced by one East African clan at communal dens. Limbs and skulls of prey animals more frequently appear at dens than do other carcass portions. These items reflect the relative abundance of prey species near dens; carnivore remains are poorly represented. Comparative analysis reveals that bones are deposited far more slowly (<7 carcass portions per month) and accumulations tend to be smaller at Crocuta dens than at dens of either brown (Parahyaena brunnea) or striped (Hyaena hyaena) hyenas. We propose that extant Crocuta bone accumulation rates and sizes are likely affected by prey species abundance, clan size, social interactions within the clan, and the type and availability of den sites. We also suggest that the potential for intraspecific behavioral variability in bone accumulation patterns is important when comparisons are made among spotted hyena populations and across hyena species. For example, accumulation patterns may be dramatically influenced by the temporal span, potentially ranging from days to hundreds or thousands of years, in which bones are collected, depending on the species-specific history of occupation at a given site. Understanding the behavioral and ecological variability likely to influence bone accumulation patterns at dens used by different hyaenids will allow taphonomists and zooarchaeologists to refine their knowledge of mechanisms underlying site formation processes and potential causes of variability in deeper-time den assemblages.

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Post-weaning maternal effects and the evolution of female dominance in the spotted hyena

Proceedings of The Royal Society B Biological Sciences ◽

10.1098/rspb.2009.0268 ◽

2009 ◽

Vol 276 (1665) ◽

pp. 2291-2298 ◽

Cited By ~ 40

Author(s):

Heather E. Watts ◽

Jaime B. Tanner ◽

Barbara L. Lundrigan ◽

Kay E. Holekamp

Keyword(s):

Crocuta Crocuta ◽

Female Dominance ◽

Spotted Hyena ◽

Compensatory Mechanism ◽

Feeding Apparatus ◽

Skull Development ◽

Spotted Hyenas ◽

Selection For ◽

Maternal Presence ◽

New Hypothesis

Mammalian societies in which females dominate males are rare, and the factors favouring the evolution of female dominance have yet to be clearly identified. We propose a new hypothesis for the evolution of female dominance and test its predictions with empirical data from the spotted hyena ( Crocuta crocuta ), a well-studied species characterized by female dominance. We suggest that constraints imposed by the development of a feeding apparatus specialized for bone cracking, in combination with the intensive feeding competition characteristic of spotted hyenas, led to the evolution of female dominance. Specifically, we propose that protracted development of the feeding apparatus in young hyenas led to selection for increased aggressiveness in females as a compensatory mechanism for mothers to secure food access for their young after weaning. Our analyses yielded results consistent with this hypothesis. Morphological and behavioural measurements indicate that skull development is indeed protracted in this species; spotted hyenas do not achieve adult skull size or feeding performance capabilities until after sexual maturity. The period between weaning and completed skull development is particularly challenging, as indicated by high mortality. Finally, maternal presence between weaning and full skull maturity, as well as the relative ability of females to aggressively displace conspecifics from food, are important determinants of offspring survival.

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Age-related variation in threat-sensitive behavior exhibited by spotted hyenas: observational and experimental approaches

Behaviour ◽

10.1163/000579510x502745 ◽

2010 ◽

Vol 147 (8) ◽

pp. 1009-1033 ◽

Cited By ~ 6

Author(s):

Wiline Pangle ◽

Kay Holekamp

Keyword(s):

Crocuta Crocuta ◽

Ontogenetic Variation ◽

Playback Experiments ◽

Related Variation ◽

Naturally Occurring ◽

Age Related ◽

Spotted Hyenas ◽

Experimental Approaches ◽

Sensitive Behavior

AbstractWe examined ontogenetic variation in threat-sensitive behaviors exhibited by spotted hyenas (Crocuta crocuta). We documented naturally-occurring vigilance throughout ontogeny, and used playback experiments to evaluate age-related variation in hyenas' responses to control sounds or lion roars. We inquired whether juveniles respond to lions more cautiously than do adults. Naturalistic observations showed that juveniles are less vigilant than adults when no immediate threat is present, but more vigilant than adults when lions are present. Our playback experiments revealed that both adult and juvenile hyenas moved in response to lion roars but not to control sounds, and their reactions were stronger to roars emitted by male than female lions. However, juveniles showed a stronger response to lions than adults, as expressed by spending more time avoiding speakers after roar onset, and by having a shorter latency to first movement than adults. Like adults, juvenile hyenas, thus, appear to recognize certain signals as dangerous and respond accordingly. However, our data suggest that young hyenas may need experience with danger early in life to learn the environmental circumstances under which they ought to be vigilant when no threat is immediately apparent.

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