Note on the unique physiologic state of loggerhead sea turtles (Caretta caretta) during nesting season as evidenced by a suite of health variables

Abstract

Baseline hematologic and plasma biochemical analytes provide insight into wildlife health. In recent years, blood analytes have been used to infer foraging strategies and nutritional status of female sea turtles of different species during nesting season in an effort to determine if turtles at this life stage are capital breeders that forage little to none during nesting season. These changes in foraging during nesting have not been documented in loggerhead sea turtles (Caretta caretta). The objective of this study was to evaluate correlations between hematologic, plasma chemistry, immune function, and antioxidative analytes of female loggerhead turtles during nesting season to determine evidence of reduced foraging. We found that chloride tended to increase, while total protein, various plasma protein fractions (pre-albumin, alpha-1-globulins, beta-globulins, total globulins), total white blood cells, superoxide dismutase, reactive oxygen species, iron, and triglycerides decreased over the course of nesting season. These results suggest that loggerhead turtles rely on fat stores accumulated on foraging grounds to fuel their energetic costs during nesting. Our results also indicate alterations in hemodynamics, metabolism, and antioxidative capacity due to reduced foraging and high energy efforts of nesting, which lend further insight into the physiologic dynamics and catabolic state of sea turtles during nesting season.