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Zuberbühler, Klaus

Nom
Zuberbühler, Klaus
Affiliation principale
Fonction
Professeur ordinaire
Email
klaus.zuberbuehler@unine.ch
Identifiants
https://libra.unine.ch/handle/123456789/670
_
0000-0001-8378-088X

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  • Publication
    Accès libre
    Predator-deterring alarm call sequences in Guereza colobus monkeys are meaningful to conspecifics
    (2010)
    Schel, Anne Marijke
    ;
    Candiottia, Agnès
    ;
    Zuberbühler, Klaus 
    Guereza colobus monkeys, Colobus guereza, produce acoustically conspicuous vocalizations, the roars, in response to their main predators, leopards, Panthera pardus, and crowned eagles, Stephanoaetus coronatus. Roaring alarm utterances generally consist of the same basic call types but differ in overall structural composition. Leopards trigger roaring alarms containing many roaring sequences of only a few calls each, while eagles trigger few sequences with many calls each. To investigate whether conspecifics extract meaning from these structural differences, we played back leopard and eagle alarm call sequences and compared the monkeys’ responses in terms of their locomotor, gaze and vocal behaviour with their responses to the corresponding predator vocalizations. Locomotor responses did not differ between playback conditions; movement was always towards the simulated caller with no clear patterns in the vertical plane. Gaze direction, however, was highly predator specific. When hearing leopard-related stimuli, monkeys were significantly more likely to scan the area beneath them than when hearing eagle-related stimuli, which caused more scanning above. Vocal response rates to conspecific alarms were generally low but comparable with rates to the corresponding predators. If monkeys called, however, they produced the matching call sequences. Overall, our results showed that Guerezas discriminated between predator alarm call sequences produced by unfamiliar conspecifics and responded to them in predator-specific ways. Since the sequences were composed of the same basic call types, we concluded that the monkeys attended to the compositional aspects of these utterances.
  • Publication
    Accès libre
    Responses to leopards are independent of experience in Guereza colobus monkeys
    (2009)
    Schel, Anne Marijke
    ;
    Zuberbühler, Klaus 
    How primates learn to recognise the predatory species from their animate world is a largely unresolved problem. We conducted predator encounter experiments with wild Guereza colobus monkeys of the Sonso area of Budongo Forest, Uganda. The monkeys are hunted by crowned eagles and chimpanzees, but not leopards, which have been locally extinct for decades. Despite their unfamiliarity with this predator, monkeys reliably produced appropriate anti-predator behaviour to leopards, which was indistinguishable from that of a neighbouring population, where leopards are present. In both populations, monkeys produced the same vocal responses and predator-specific alarm calls, although leopard-naïve monkeys were more inclined to approach when hearing a leopard than monkeys that were familiar with this predator. Control experiments showed that the monkeys’ response pattern was not due to the effects of unfamiliarity or conspicuousness of the experimental stimuli. Natural selection appears to have endowed these primates with a cognitive capacity to recognise direct signs of leopard presence as inherently dangerous requiring specific anti-predator responses.
  • Publication
    Accès libre
    The alarm call system of two species of black-and-white colobus monkeys (Colobus polykomos and Colobus guereza)
    (2009)
    Schel, Anne Marijke
    ;
    Tranquilli, Sandra
    ;
    Zuberbühler, Klaus 
    Vervet monkey alarm calling has long been the paradigmatic example of how primates use vocalizations in response to predators. In vervets, there is a close and direct relationship between the production of distinct alarm vocalizations and the presence of distinct predator types. Recent fieldwork has however revealed the use of several additional alarm calling systems in primates. Here, the authors describe playback studies on the alarm call system of two colobine species, the King colobus (Colobus polykomos) of Taï Forest, Ivory Coast, and the Guereza colobus (C. guereza) of Budongo Forest, Uganda. Both species produce two basic alarm call types, snorts and acoustically variable roaring phrases, when confronted with leopards or crowned eagles. Neither call type is given exclusively to one predator, but the authors found strong regularities in call sequencing. Leopards typically elicited sequences consisting of a snort followed by few phrases, while eagles typically elicited sequences with no snorts and many phrases. The authors discuss how these call sequences have the potential to encode information at different levels, such as predator type, response-urgency, or the caller’s imminent behavior.
  • Publication
    Accès libre
    Male blue monkeys alarm call in response to danger experienced by others
    (2008)
    Papworth, Sarah
    ;
    Böse, Anne-Sophie
    ;
    Barker, Jessica
    ;
    Schel, Anne Marijke
    ;
    Zuberbühler, Klaus 
    Male blue monkeys (Cercopithecus mitis stuhlmanni) of Budongo Forest, Uganda, produce two acoustically distinct alarm calls: hacks to crowned eagles (Stephanoaetus coronatus) and pyows to leopards (Panthera pardus) and a range of other disturbances. In playback experiments, males responded to leopard growls exclusively with a series of pyows and to eagle shrieks predominantly with hacks. Responses to playbacks of these alarm call series matched the responses to the corresponding predators, suggesting that the calls conveyed something about the nature of the threat. When responding to a series of hacks, indicating an eagle, males responded predominately with hacks, but produced significantly more calls if their group members were close to the playback stimulus than far away, regardless of their own position. When responding to a series of pyows, indicating a range of disturbances, males responded with pyows, but call rates were independent of the distance of other group members. The results suggest that males took into account the degree of danger experienced by other group members.