@article {53395, title = {The importance of group vocal behaviour in roost finding}, journal = {Animal Behaviour}, volume = {142}, year = {2018}, month = {Jan-08-2018}, pages = {157 - 164}, abstract = {

Individuals benefit from socially acquired information to avoid predation risks and enhance foraging efficiency. Spix\&$\#$39;s disc-winged bats, Thyroptera tricolor, form very stable social groups despite their need to find a new roosting site daily. Thyroptera tricolor produce two contact calls: inquiry calls, emitted during flight, and response calls, produced by bats after finding a suitable roost (in a furled leaf). Bats within social groups exhibit consistent individual differences in vocal behaviour and thus, groups are composed by a mix of less vocal and more vocal individuals. To date, it is not known whether consistent individual differences in contact calling behaviour decrease the time required for roost finding and whether vocal behaviour is correlated with an individual\&$\#$39;s ability to quickly locate roosts, thus constituting a behavioural syndrome. Here, we compared the time spent by social groups in finding roosts when a bat called from inside the roost, either frequently or infrequently. Moreover, we estimated how well calling rates inside a roost predicted a bat\&$\#$39;s ability to later find a new roost. Results of behavioural experiments and field observations show that social groups enter roosts faster when the bat inside the roost called more. This suggests that more frequent calling decreases search time, which may allow groupmates to save energy and decrease exposure to predators. Moreover, vocal activity also predicted discovery of more roosts (furled leaves) in their natural habitat, which emphasizes the relevance of more vocal individuals for the group. Our work represents a step in understanding the importance of communication and individual vocal behaviour in group formation and stability in gregarious animals.

}, keywords = {animal personality, bat, behavioural syndrome, contact call, Thyroptera tricolo}, issn = {00033472}, doi = {10.1016/j.anbehav.2018.06.018}, url = {https://linkinghub.elsevier.com/retrieve/pii/S000334721830201Xhttps://api.elsevier.com/content/article/PII:S000334721830201X?httpAccept=text/xmlhttps://api.elsevier.com/content/article/PII:S000334721830201X?httpAccept=text/plain}, author = {Sagot, Maria and Sch{\"o}ner, Caroline R. and Jago, Abigail J. and Razik, Imran and Chaverri, Gloriana} } @article {53350, title = {Acoustic similarity elicits responses to heterospecific distress calls in bats (Mammalia: Chiroptera)}, journal = {Animal Behaviour}, volume = {146}, year = {2018}, month = {Jan-12-2018}, pages = {143 - 154}, abstract = {

Frequently, individuals of one species respond to alarm calls produced by another species. This form of interspecies communication can be critical for survival. How animals recognize and respond to heterospecific alarm calls is, however, still poorly understood. This is especially true for bats, which are highly vocal and possess a specialized auditory system. We hypothesized that, among bat species, acoustic similarity between heterospecific and conspecific alarm calls is a key factor that underlies call recognition. However, this ability could also be acquired via associative learning from prior exposure or result from phylogenetic relatedness among caller and receiver species, as shown by others. Here we focused on distress calls of bats as representing a certain type of alarm call. To test our hypothesis, we recorded distress calls of 11 bat species from four families at five different sites. We broadcast the recorded calls to three of these species (Rhinolophus sinicus, Myotis badius and Myotis laniger). For all three species, neither prior exposure (familiarity) nor phylogenetic relatedness explained the variation in the response strength, as measured by echolocation vocalizations of receiver species in response to playback of heterospecific distress calls. In contrast, acoustic similarity, especially in peak frequency, between conspecific and heterospecific distress calls, was positively correlated with response strength in the receiver species. Thus, our findings emphasize that, at least among bats, acoustic similarity is a key factor allowing recognition of heterospecific alarm calls. It remains unclear whether evolutionary, genetic and/or neurophysiological mechanisms entrain an individual to respond selectively to a specific acoustic feature.

}, keywords = {acoustic similarity, bat, distress call, interspecific eavesdropping, learning, peak frequency, phylogenetic relatedness}, issn = {00033472}, doi = {10.1016/j.anbehav.2018.10.018}, url = {https://linkinghub.elsevier.com/retrieve/pii/S0003347218303191https://api.elsevier.com/content/article/PII:S0003347218303191?httpAccept=text/xmlhttps://api.elsevier.com/content/article/PII:S0003347218303191?httpAccept=text/plain}, author = {Huang, Xiaobin and Metzner, Walter and Zhang, Kangkang and Wang, Yujuan and Luo, Bo and Sun, Congnan and Jiang, Tinglei and Feng, Jiang} } @article {53289, title = {Resource Ephemerality Drives Social Foraging in Bats}, journal = {Current Biology}, year = {2018}, month = {Jan-11-2018}, abstract = {

Observations of animals feeding in aggregations are often interpreted as events of social foraging, but it can be difficult to determine whether the animals arrived at the foraging sites after collective search [1, 2, 3, 4] or whether they found the sites by following a leader [5, 6] or even independently, aggregating as an artifact of food availability [7, 8]. Distinguishing between these explanations is important, because functionally, they might have very different consequences. In the first case, the animals could benefit from the presence of conspecifics, whereas in the second and third, they often suffer from increased competition [3, 9, 10, 11, 12, 13]. Using novel miniature sensors, we recorded GPS tracks and audio of five species of bats, monitoring their movement and interactions with conspecifics, which could be inferred from the audio recordings. We examined the hypothesis that food distribution plays a key role in determining social foraging patterns [14, 15, 16]. Specifically, this hypothesis predicts that searching for an ephemeral resource (whose distribution in time or space is hard to predict) is more likely to favor social foraging [10, 13, 14, 15] than searching for a predictable resource. The movement and social interactions differed between bats foraging on ephemeral versus predictable resources. Ephemeral species changed foraging sites and showed large temporal variation nightly. They aggregated with conspecifics as was supported by playback experiments and computer simulations. In contrast, predictable species were never observed near conspecifics and showed high spatial fidelity to the same foraging sites over multiple nights. Our results suggest that resource (un)predictability influences the costs and benefits of social foraging.

}, keywords = {bat, behavioral ecology, echolocation, foraging, GPS, movement ecology, navigation, sociobiology}, issn = {09609822}, doi = {10.1016/j.cub.2018.09.064}, url = {https://linkinghub.elsevier.com/retrieve/pii/S0960982218312909https://api.elsevier.com/content/article/PII:S0960982218312909?httpAccept=text/xmlhttps://api.elsevier.com/content/article/PII:S0960982218312909?httpAccept=text/plain}, author = {Egert-Berg, Katya and Hurme, Edward R. and Greif, Stefan and Goldstein, Aya and Harten, Lee and Herrera M., Luis Gerardo and Flores-Mart{\'\i}nez, Jos{\'e} Juan and Vald{\'e}s, Andrea T. and Johnston, Dave S. and Eitan, Ofri and Borissov, Ivo and Shipley, Jeremy Ryan and Medellin, Rodrigo A. and Wilkinson, Gerald S. and Goerlitz, Holger R. and Yovel, Yossi} }