Vocalizaciones del cocodrilo americano, Crocodylus acutus (Cuvier, 1807) durante la eclosión
American Crocodile, Crocodylus acutus (Cuvier, 1807) Vocalizations Prior to Hatching
Abstract
Crocodiles exhibit a broad spectrum of calls and vocalizations during their lives and even immediately before hatching. For this study, vocalizations of American crocodile neonates (Crocodylus acutus) immediately prior to hatching (breaking open the egg shell) were digitalized and analyzed using 4.85 minutes of recordings from two individuals. With the aid of Raven® software, the corresponding sonograms and spectrograms were made, finding that all vocalizations were composed of a single, modulated short note varying between 8.7 and 28.3 milliseconds (ms) duration and repeated at regular intervals of 2.6 seconds each. The dominant frequency was located between 652 and 1394 Hz. Calls of the individuals from inside the eggs could act as a signal to other embryos in the same nest to synchronise and break open their eggs. They also stimulate the mother to open the nest and provide protection against possible predators.
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References
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