Hyenas Vs Leone

sethology
international journal of behavioural biology

Ethology

Responses of Spotted Hyenas to Lions Reflect Individual Differences in Behavior
Heather E. Watts, Lisa M. Blankenship, Stephanie E. Dawes & Kay E. Holekamp
Department of Zoology, Michigan State University, East Lansing, MI, USA

Correspondence Heather E. Watts, Department of Biology, Loyola Marymount University, LosAngeles, CA 90045, USA. E-mail: hwatts1@lmu.edu

Abstract Competition among mammalian carnivores can be particularly intense and can influence population dynamics at lower trophic levels. One strategy employed by carnivores to minimize potentially costly interspecific competition is avoidance of dominant species. Recent research has highlighted the importance of consistent individual differences inbehavior (i.e. temperament traits) in understanding behavioral variation during predator–prey interactions and intraspecific interactions. However, the importance of such individual differences to interspecific competition has received little attention. Here, we examined the responses of spotted hyenas (Crocuta crocuta) to their primary competitors, African lions (Panthera leo), to (1) determine whetherhyenas avoid lions and (2) evaluate the potential importance of individual differences in behavior during interspecific competition. Spotted hyenas and lions co-occur throughout much of Africa and are vigorous competitors. Whereas lions sometimes kill hyenas and steal their food, lions also represent a source of food for hyenas via scavenging. Using audio playback experiments, we found that hyenasdo not uniformly avoid potential encounters with lions. Indeed, we noted considerable variation among individuals in their responses to lion roars, and this variation reflected consistent individual differences in risk-taking and vigilance tendencies. Individual differences in vigilance behavior were specific to interactions with lions. We conclude that individual differences in behavior have thepotential to play an important role in determining the nature and outcome of interspecific competition.

Received: May 20, 2010 Initial acceptance: July 2, 2010 Final acceptance: August 25, 2010 (L. Ebensperger)
doi: 10.1111/j.1439-0310.2010.01833.x

Introduction It is increasingly recognized that interspecific competition among carnivores is both widespread and ecologically important because ofits effects on community structure and dynamics (Linnell & Strand 2000; Caro & Stoner 2003). Interspecific competition among predators can not only adversely affect subordinate species within the guild, including numerous threatened species (Laurenson 1995; Creel & Creel 1996; Helldin et al. 2006; Trewby et al. 2008), but it can also have cascading effects at lower trophic levels (Palomares et al.1995; Rogers & Caro ´ 1998; Crooks & Soule 1999). Therefore, understandEthology 116 (2010) 1199–1209 ª 2010 Blackwell Verlag GmbH

ing the dynamics of these competitive interactions is of both theoretical and practical importance. One manifestation of interspecific competition is avoidance behavior. Carnivores may mitigate the deleterious consequences of direct intraguild competition by shiftingpatterns of space use to avoid dominant species (Mills & Mills 1982; Palomares et al. 1996; Durant 2000a; Creel et al. 2001). However, avoidance behavior can impose significant energetic costs; for instance, the subordinate species may be relegated to areas with lower prey availability (Creel & Creel 2002). Given these trade-offs, it is not surprising that we observe variation in avoidance behavioramong species (White et al. 1994), as well
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Responses of Spotted Hyenas to Lions

H. E. Watts, L. M. Blankenship, S. E. Dawes & K. E. Holekamp

as within species. For example, studies of cheetahs (Acinonyx jubatus) have demonstrated that age, hunger level, and the presence of prey, all contribute to variation in avoidance of larger competitors (Durant 2000a,b). Another factor that...