Amaury Cordero-Tapia – acordero@cibnor.mx
Eduardo Romero-Vivas – evivas@cibnor.mx
CIBNOR
Mar Bermejo 195
Playa Palo de Santa Rita Sur 23090
La Paz, BCS, Mexico
Popular version of paper 3aAB8, “Opportunistic underwater recording of what might be a distress call of Chelonya mydas agassizii”
Presented Wednesday morning, December 6, 2017, 10:15-10:30 AM, Salon F/G/H
174th ASA Meeting, New Orleans, Louisiana
Click here to read the abstract.
Sea turtles are considered “the least vocal of all living reptiles” (DOSIT), since their vocalization has been documented only during nesting (Cook & Forrest, 2005). Although they distribute worldwide in the oceans, there seems to be no recordings of sounds produced by them, perhaps until now.
In Baja California Sur Mexico there is a conservation program run by Government Authorities, Industry, and Non-Governmental Agencies focused on vulnerable, threatened and endangered marine species. In zones of high density of sea turtles, special nets, which allow them to surface for breathing, are deployed monthly for monitoring purposes. Nets are checked by divers every 2 hours during the 24 Hrs. of the census.
During one of these checks a female specimen of Green Turtle (Chelonya mydas agassizii) was video recorded using an action cam. Posterior analysis of the underwater recording showed a clear pattern of pulsed sound when the diver was at close proximity to the turtle. The signal covers the reported audition range for this species (Ketten & Bartol, 2005; Romero-vivas & Cordero-Tapia, 2008) and given the circumstances we think that it might be a distress call. With more recordings we will confirm if such is the case, although this first recording gives an initial hint of what to look for. Maybe sea turtles are not that silent; there was just no need to break the silence
Figure 1. Green turtle in the special net & sound recording
Dosits.org. (2017). DOSITS: How do sea turtles hear?. [online] Available at: http://dosits.org/animals/sound-reception/how-do-sea-turtles-hear/ [Accessed 16 Nov 2017].
Cook, S. L., and T. G. Forrest. 2005, Sounds produced by nesting Leatherback sea turtles (Dermochelys coriacea). Herpetological Review 36:387–390.
Ketten, D.R. and Bartol, S.M. 2005, Functional Measures of Sea Turtle Hearing. Woods Hole Oceanographic Institution: ONR Award No: N00014-02-1-0510.
Romero-Vivas, E. and Cordero-Tapia, A. 2008, Behavioral Acoustic Response of two endangered sea turtle species: Chelonia Mydas Agassizzi –Tortuga Prieta- and Lepidochelys Olivaceas –Tortuga Golfina- XV Mexican International Congress on Acoustics, Taxco 380-385.