Reconstructing Stress and Stressor Profiles in Baleen Whale Earplugs
Abstract
Reconstructing lifetime stress profiles (i.e. birth to death) using baleen whale earplugs, research developed by the Pis Usenko and"" Trumble, is uniquely capable of assessing stress trends temporally and spatially. This reconstruction technique combines age estima"tes (i.e. counting light and dark lamina) with chemical or elemental analysis (e.g. hormones) of each waxy layer (lamina). In additi"on, the PIs have also developed a strong external network for earplug collection and preservation including recent strandings and mu""seum holdings from several countries. Moreover, our team has been able to acquire additional tissues such as blubber, baleen and mus"cle to analyze against the corresponding earplug as a means of providing additional scientific rigor and validation. This research will focus on the following objectives: 1) expand earplug datase to include additional species/populations to assess variation in stress at the individual and population level; 2) determine population level variability in lifetime stress-related hormones profiles of large whales and to normalize baseline among individuals and species; 3) assess and validate the accuracy and precision of measurements of hormones and other biomarkers in earplugs with other tissues collected from same individuals including blubber and baleen; 4) expand the list of stressors biomarkers from each lamina within each earplug and determine its potential relationship to lifetim"e stress profiles (e.g. DNA, stable isotopes, and metals) and finally, 5) expand the analytical rigor and sensitivity through improv"ed hormone characterization using ultra performance liquid chromatography tandem mass spectrometry. This proposed research builds on" the success of our previously funded ONR project (Award Number N000141410415), which identified individual baseline and reconstruct""ed lifetime profiles of stress-related hormone levels in baleen whales. To date, twenty (N=20) baleen whale earplugs representing an" unprecedented 147-year time series of reconstructed cortisol (stress) profiles spanning 1869 to 2016 from individual whales from fo"ur species (fin, humpback, blue, and minke whales) aged 1.5 to 63 years have been analyzed."" The NAS reported the significance of this line of research as ""the only shortcut fou"nd by the Committee for retrospective studies of health and vital rates where one can use tissue from dead animals to study these re"lationships from birth to death."" The NAS report also specified, ""if large enough samples of earplugs can be recovered and analyzed"" for health and vital rates, this could enable a new way to evaluate the relationship between these critical parameters."" This propo"sed study will examine lifetime stress-related hormonal levels in large whales and will transform our understanding of the extent of" exposure and the potential effect on health of these animals. In addition, this research offers exponential research opportunities" that simply does not exist with traditional matrices such as blood and/or blubber and is ideally suited for examining stress-related hormones over an organism s lifetime.
Document Details
- Document Type
- DoD Grant Award
- Publication Date
- Sep 01, 2017
- Source ID
- N000141712755
Entities
People
- Stephen J Trumble
Organizations
- Baylor University
- Office of Naval Research
- United States Navy