Comparison of body temperature and heart rate in sea turtles from Baja California Sur, Mexico

Abstract

Sea turtles depend on ambient temperature to carry out their main activities, so changes in water temperature can affect the function of their immune system and represent different threats. To assess vital signs in black sea turtles (Chelonia mydas) in the Ojo de Liebre lagoon complex, Mexico, 600 turtles were examined. Carapace, plastron, and left inguinal area temperatures were measured with a digital infrared thermometer gun. Cloacal temperature was measured with an electronic thermometer. Heart rate was recorded using a stethoscope. Statistical analyses found no significant variation between inguinal area and cloacal temperatures. Vital sign measurements were compared with previous reports in the region, and there were differences in body temperatures, which were attributed to the characteristics of the water masses inhabited by the turtles. There was no significant difference between heart rate data for black sea turtles in this study and previously reported data for healthy sea turtles in the region, indicating that these data are likely an accurate representation for the species. All values fell within the reference intervals for healthy sea turtles. This minimally invasive diagnostic approach using vital signs allowed us to evaluate and infer core organ functions and to rule out health threats such as cold-stunning, resulting in a useful preliminary systemic assessment of free-ranging sea turtles.