Background
Daily variation in behavior and physiology is observed across many species, often following an approximately 24-hour cycle influenced by environmental cues such as light and temperature. Specifically, in marine turtles, these rhythms influence hormone secretion, activity levels, and diving behavior. While behavioral and hormonal studies have provided valuable insights, little is known about the physiological mechanisms underlying these patterns, particularly how they impact heart rate and respiration.
Heart rate is a key physiological indicator of metabolism and health in terrestrial mammals. Due to turtles’ anatomy (the presence of a hard shell), the traditional methods for measuring sea turtles’ heart rates are invasive, requiring anesthesia or electrode insertion. Nevertheless, recent advancements in non-invasive heart rate monitoring now offer new opportunities to explore physiological rhythms with minimal disturbance.
Despite these recent advancements, the response of sea turtles’ heart rates to different conditions remains uncertain, as unclear states of consciousness, fluctuating oxygen availability, and temperature could all influence it, adding layers of complexity to the interpretation of heart rate fluctuation in sea turtles.
Aims
This study aimed to investigate the influence of day and night on sea turtles’ heart rate during 28 hours, taking into account activity, and breathing frequency.
