Playback of Fork-Marked Lemurs' Loud Calls in Kirindy Forest, Madagascar

Primate loud calls often encode information relating to species identity. A previous study of loud calls of fork-marked lemurs (genus Phaner) indicated differences among the calls of four populations that have been accorded species status on the grounds of morphology and biogeography: Phaner electromontis, P. parienti, P. furciferand P. pallescens. I made field recordings of two typical calls (kiu and kea) emitted by all four populations and conducted playback experiments in Kirindy Forest to investigate whether free-ranging P. pallescensindividuals could discriminate the loud calls of their own species from those of others. Individual response behaviour, social context and call type used in playback were analysed using a goodness-of-fit G test. The effect of specific call identity was significant, while the effects of context and call type were not. Individuals responded to P. pallescens calls by approaching the speaker, but not to the calls of other populations. P. pallescens individuals appear to be capable of distinguishing the loud calls of their conspecifics, but the fact that the habitat structure of the sites of recording and playback of P. pallescenscalls was similar sounds a note of caution. Future studies should repeat the experiments with the other populations of fork-marked lemurs.