Study of a biosonar based on the modeling of a complete chain of emission-propagation-reception with validation on sperm whales

• Main Author: Ferrari, Maxence
• Other Authors: Laboratoire Amiénois de Mathématique Fondamentale et Appliquée - UMR CNRS 7352 UPJV (LAMFA), Université de Picardie Jules Verne (UPJV)-Centre National de la Recherche Scientifique (CNRS), Université de Picardie Jules Verne, Mark Asch, Hervé Glotin, Ricard Marxer
• Format: Doctoral or Postdoctoral Thesis
• Language: English
• Published: HAL CCSD 2020
• Subjects: Sperm whale; Sonar; Simulation; Cachalot; [MATH.MATH-GM]Mathematics [math]/General Mathematics [math.GM]; Physeter macrocephalus
• Online Access: https://theses.hal.science/tel-03626254; https://theses.hal.science/tel-03626254/document; https://theses.hal.science/tel-03626254/file/TheseFerrari.pdf

The sperm whale, Physeter macrocephalus, posses the largest biosonar in nature. Made of multiple oil sac, the sperm whale sonar is tailored to function from the sea surface down to a depth of 2 kilometers, emitting click as loud as 236 dB, and is multipurpose, as it produces clicks for either echolocation or socializing. However, the liquid wax that composes is sonar, made the sperm whales the target of whaling until 1986, when the remaining population was far too small to remain commercially viable, especially with the arrival of similar products from the petrochemical industry. The sperm whale population still faces some human threats, with the ingestion of plastic and collision with boats continuing to take a toll on the sperm whale population. Studying sperm whales thus aport outcomes in multiple fields, in conservation, ethology, as well as in bioacoustics. Understanding the mechanism that rules the sperm whale sonar will help to study those other fields, as it is a key element in the sperm whale life. Aiming for that goal, this thesis analyzed three databases with distinct characteristics, obtaining the trajectory of sperm whale dives. Clicks were also linked with the sperm whale that emitted them over multiple years of recording for the same population. A simulation of propagation wave through the sperm whale head was also developed to better understand the complex mechanism of this sonar. Finally, a coupling method was developed to improve the parameters of the simulation using the recorded clicks from the aforementioned databases Le cachalot, Physeter macrocephalus, possède le plus grand biosonar de la nature. Composé de plusieurs poches d'huile, le sonar du cachalot est conçu pour fonctionner de la surface de la mer jusqu'à une profondeur de 2 kilomètres, émettant des clics pouvant aller jusqu'à 236 dB, et est polyvalent, car il produit des clics pour l'écholocation ou la socialisation. Cependant, la cire liquide qui compose le sonar a fait des cachalots la cible de la chasse jusqu'en 1986, lorsque ...