Visualizing sound: counting wolves by using a spectral view of the chorus howling

摘要: Introduction Monitoring large carnivores is a central issue in conservation biology. The wolf (Canis lupus) the most studied carnivore world. After massive decline and several local extinctions, mostly due to direct persecutions, wolves are now recolonizing many areas of their historical natural range. One main monitoring techniques howling survey, which based on wolves’ tendency use vocalisations mark territory ownership response howls unknown individuals. In cases sessions useful for localisation pack, but they provide only an aural estimation chorus size. We tested present new bioacoustic approach estimate size by recording replies visualising choruses through spectrograms spectral envelopes. To test methodology, we compared: a) values detected visual inspections with true accuracy; b) estimations sample free-ranging developed different operators precision method; c) field sonogram analysis same recordings difference between methods.