Call and be counted! Can we reliably estimate the number of callers in the indri's (Indri indri) song?

摘要: Estimating the number of animals participating in a choral display may contribute reliable information on animal population estimates, particularly when environmental or behavioral factors restrict possibility visual surveys. Difficulties providing estimate singers chorus are many (e.g., background noise masking, overlap). In this work, we contributed data vocal chorusing indri lemurs (Indri indri), which emit howling cries, known as songs, uttered by two to five individuals. We examined whether could emitters screening fundamental frequency spectrograms and total duration reliability those methods compared real size. The spectrographic investigation appears provide only is limited three singers. also found that Acoustic Complexity Index positively correlated with size, showing an automated analysis about can state song shows correlation but remarkable variation remains unexplained. accuracy estimates reflect high variability be affected group composition, season context. future research, greater focus analyzing change occurring during these collective displays should improve our ability detect individuals allow finer tuning acoustic serve for monitoring mammals.