@article {53370, title = {Experimental evidence that titi and saki monkey alarm calls deter an ambush predator}, journal = {Animal Behaviour}, volume = {145}, year = {2018}, month = {Jan-11-2018}, pages = {141 - 147}, abstract = {

Many animals use alarm calls in intraspecific communication to warn conspecifics of a predator\&$\#$39;s presence or to elicit coordinated group responses. However, alarm calls may also be aimed directly at the predator to discourage further pursuit. These \&$\#$39;pursuit-deterrent\&$\#$39; signals are particularly important in the presence of ambush predators that rely on stealth to hunt prey. Here, we conducted playback experiments over a 16-month period on radiocollared ocelots, Leopardus pardalis, in Peru using audio stimuli of titi monkey (Callicebus toppini) and saki monkey (Pithecia rylandsi) alarm calls, with nonalarm loud calls as controls. We predicted that, if titi and saki alarm calls function as deterrent signals, then ocelots would move away from the sound source and leave the area following exposure to alarms but not following controls. We tracked ocelots via radiotelemetry for 30 min prior to and 30 min following experiments. At 15 min intervals we noted subject location, whether the cat was stationary or moving towards, away from or parallel to the playback area (calculated using a deflection angle) and distance travelled. Results showed a significantly different pattern in response movement between playback trials; ocelots moved away from the sound source in the majority of alarm trials but remained stationary/hidden or moved in a variety of directions following control trials. Ocelots also moved significantly farther following exposure to alarm trials than following exposure to controls. We conclude that ocelots can distinguish alarm calls from other loud calls and are deterred by alarm-calling monkeys. This is the first study to use playbacks on wild predators to test the pursuit-deterrent function of primate alarm calls.

}, keywords = {Callicebus, interspecific communication, Leopardus pardalisocelot, perception advertisement, Pithecia, playback experiment, pursuit-deterrent signal, radiotelemetry}, issn = {00033472}, doi = {10.1016/j.anbehav.2018.09.010}, url = {https://linkinghub.elsevier.com/retrieve/pii/S000334721830280Xhttps://api.elsevier.com/content/article/PII:S000334721830280X?httpAccept=text/xmlhttps://api.elsevier.com/content/article/PII:S000334721830280X?httpAccept=text/plain}, author = {Adams, Dara B. and Kitchen, Dawn M.} } @article {53261, title = {Sing softly to evoke a response only from a recent intruder}, journal = {Behavioural Processes}, volume = {157}, year = {2018}, month = {Jan-12-2018}, pages = {244 - 249}, abstract = {

Low-amplitude soft songs have been described in many birds, but in most species, research has addressed only broadcast songs. Soft songs may have a similar or distinctive structure in comparison to broadcast songs produced in order to defend a territory and attract females. In some species, such soft songs were found to be produced in an aggressive context and were the best predictors of conflict escalation and later physical attack. However, such observations are not consistent across all species studied. Several hypotheses have been put forward to explain the function(s) of soft songs and why they are so quiet. Studies on the ortolan bunting (Emberiza hortulana) show that males produce soft songs similar in structure to broadcast songs during close interactions with conspecific intruders. However, experiments with the playback of loud and soft songs as well as taxidermic mount presentation revealed that soft song in this species does not fulfil aggressive signal criteria. Here we performed an experiment with two loudspeakers simulating movements of the intruder in order to test whether the soft songs are used to evoking a response from a nearby but not localised rival. We found that males responded with similar strength to songs played back from single and double speaker systems. Simultaneously, males produced more soft songs during and just after the phase of the experiment in which we simulated short flights of the intruder. Our results indicate that soft songs might be used during close interactions with rivals without being an aggressive signal and are used as short-range signals to check if the rival is still around. Our results also provide an alternative explanation of soft song behaviour in comparison to the hypotheses of eavesdropping avoidance and readiness to fight.

}, keywords = {Aggressive signals, Emberiza hortulana, playback experiment, Territory defence}, issn = {03766357}, doi = {10.1016/j.beproc.2018.10.012}, url = {https://linkinghub.elsevier.com/retrieve/pii/S0376635718301335https://api.elsevier.com/content/article/PII:S0376635718301335?httpAccept=text/xmlhttps://api.elsevier.com/content/article/PII:S0376635718301335?httpAccept=text/plain}, author = {Jakubowska, Aleksandra and Osiejuk, Tomasz S.} } @article {50502, title = {Age-dependent change in attention paid to vocal exchange rules in Japanese macaques}, journal = {Animal Behaviour}, volume = {129}, year = {2017}, month = {Jan-07-2017}, pages = {81 - 92}, abstract = {

The mechanisms underlying vocal development in nonhuman primates, so-called \‘nonlearners\’, are of special interest because they give an insight in how social factors can shape the expression of an already genetically determined vocal repertoire. Interestingly, recent studies suggest that the acquisition of the complex rules governing vocal exchanges (i.e. context-specific temporal and structural acoustic adjustments) may result from a socially guided development process, with social experience and parental selective feedback playing a key role. Among those conversational rules, call matching is a particularly remarkable phenomenon in Japanese macaques, Macaca fuscata, with interacting adult females matching the frequency range pattern of their own call with another female\&$\#$39;s preceding call. Here, we investigated whether fine-tuned acoustic adjustments during vocal exchanges in Japanese macaques are subject to developmental processes, specifically testing for the ability of individuals of different age classes to discriminate between vocal exchanges respecting, or not, the matching rule. We performed playback experiments in 10 adult and 10 1-year-old captive Japanese macaque females. Each subject was successively exposed to two stimuli: a pair of calls respecting call matching (i.e. two calls from two individuals with matched frequency ranges) and another pair of calls that did not. Adults discriminated better than juveniles whether stimuli respected the call-matching rule or not, and displayed significantly different levels of interest towards each stimulus type. The latency to look towards the loudspeaker was shorter, and the duration of the directed gaze was longer, after the playback that violated the matching expectation in every adult, but not in juveniles which seemingly displayed a random gaze response. Our findings support the conclusion that the matching rule is relevant for adults, but not for socially inexperienced young monkeys which may not have had enough experience of the conversational rules governing vocal exchanges.

}, keywords = {call matching, Japanese Macaque, nonhuman primate, playback experiment, vocal development, vocal exchange}, issn = {00033472}, doi = {10.1016/j.anbehav.2017.05.012}, url = {http://linkinghub.elsevier.com/retrieve/pii/S0003347217301495}, author = {Bouchet, H{\'e}l{\`e}ne and Koda, Hiroki and Lemasson, Alban} }