Léo PAPET : Between air and water, the acoustic world of crocodiles

Abstract : As top predators, crocodilians are very well equipped to probe their environment: excellent vision in air, highly developed smell, extraordinary abilities of mechano-reception and an acute sense of hearing in both air and water. Crocodilians use acoustic communication throughout life to interact with other individuals, protect their juveniles and find a partner. Besides, they evolve in an amphibious environment, spending most of their active time between air and water.
The main objective of this project is to understand how crocodilians use acoustic cues to localize preys and congeners in a complex environment. This work is based on an interdisciplinary approach combining physical measurements and behavioural observations. First, the Head-Related Transfer Functions (HRTFs) were measured to characterize the external localization cues. Based on these results, different conditioning experiments were designed to quantify the localization performances and to highlight the use of these cues. Finally, the confrontation of the results obtained in the lab and the observations made on the field will allow us to answer the question of sound localization in crocodilians in their natural environment.