Abstract:
Sequentially sampled keratinous tissue provides a chronology of biochemical data. Herein, we used whiskers (vibrissae. of southern elephant seals (SES. Mirounga leonina, sampled at Marion Island in the Southern Ocean, as example, to demonstrate how time-based interpretations of the steroid and isotopic data captured along the length of the whiskers are obtainable. Bulk stable isotope dietary reconstructions are based on the principle, “you are what you eat”, and provides a powerful, indirect approach to assess the trophic ecology of an individual. However, our data suggest that pregnant females might not be “what they eat” during gestation, which contrasts with the theoretical basis of the use of stable isotope dietary reconstructions. I also aim to present our results regarding the first, successful chronologically extractions of hormones captured along the length of SES whiskers and discuss the potential of using the whisker hormone profile as “pregnancy test” in seals. Our novel, multidisciplinary combination of hormones, bulk stable isotopes, and compound-specific stable isotopes, should permit conclusions about the trophic ecology and nutritional status of the individual that can be linked to an individual’s fecundity. Information regarding the trophic ecology and physiology of SES aids our understanding of their role in the marine ecosystem, pivotal to their future utility as sentinels to gauge ocean health. - Abstract as displayed in the - Abstract booklet. The presentation on the day may differ from the - Abstract.
