Exploring the Wonders of the Arctic from a Lab Bench

Marci Trana University of Manitoba, Biological Sciences, 50 Sifton Road, Winnipeg, R3T 2N2, Canada. E-mail: marcitrana@gmail.com

A section of Beluga Whale blubber removed for use in cortisol extraction and analysis. The skin (white) is against the table surface, the dark layer at the top is muscle, and in between these layers is blubber. Photo credit: Marci Trana.

A section of Beluga Whale blubber removed for use in cortisol extraction and analysis. The skin (white) is against the table surface, the dark layer at the top is muscle, and in between
these layers is blubber. Photo credit: Marci Trana.

Like many ecologists, I have a love of fieldwork and a passion for being witness to the ecosystems I study. The field is where I make connections and develop hypotheses to explain observations of organisms in their natural environment. I have often cringed at the thought of spending all my time in a lab or pouring over data on a computer. Then I accepted a graduate position at the University of Manitoba, working with Jim Roth, Gary Anderson, Steve Ferguson, and Gregg Tomy on a project that used archived samples to examine whether cortisol levels were higher in threatened Beluga Whale Delphinapterus leucas populations when compared to healthy populations. The use of archived samples meant that I wouldn’t get into the field to collect my own samples. I accepted the position, despite the absence of a field component, because I felt that it was important for me to gain strong laboratory skills hoping that I might be sent to the field at least once, maybe twice, as an
Beluga Whales in the Churchill River estuary. Photo credit: Marci Trana.

Beluga Whales in the Churchill River estuary. Photo credit: Marci Trana.

assistant on someone else’s research. I learned far more in the lab than just becoming better about enduring the lab. I learned that spectacular science can occur at a lab bench. Lab work is not for the faint of heart; it can be just as challenging as working in the elements. To answer questions about cortisol differences among populations, we first needed to extract cortisol, a known stress hormone, from Beluga Whale blubber. We had to develop new methods because this process had never been done. I processed hundreds of blubber samples that had been collected during subsistence hunts by northern communities over the past 30 years and tried a variety of simple cortisol extraction methods, none of which yielded results. Then I discovered two publications where testosterone and progesterone had been extracted from blubber. With some slight alterations of those methods and after several attempts, I finally
Beluga Whale blubber extraction in progress. The lipid layer (light yellow) and interstitial tissue (dark yellow) pelleted against the bottom of the vial. Photo credit: Marci Trana.

Beluga Whale blubber extraction in progress. The lipid layer (light yellow) and interstitial tissue (dark yellow) pelleted against the
bottom of the vial. Photo credit: Marci Trana.

identified cortisol in blubber samples. While changed with blubber depth and among samples, depending on the quality of the sample after storage. I recorded the condition of the blubber samples and prepared a subset of samples to examine cortisol with blubber depth. These seemingly small observations in the lab led to major findings, with some beautiful data illustrating the effect of blubber depth and degradation from long-term storage on cortisol concentrations. What was originally a side note in my thesis became my first publication (Trana et al. 2015). I found that observation and speculation leading to testable hypotheses could happen just as easily in the lab as in the field. So for others who are field oriented, I encourage you to embrace opportunities in the lab, which can also be intellectually stimulating and highly rewarding. REFERENCE Trana, M. R., J. D. Roth, G. T. Tomy, W. G. Anderson, and S. H. Ferguson. 2015. Influence of sample degradation and tissue depth on blubber cortisol in Beluga Whales. Journal of Experimental Marine Biology and Ecology 462:8-13.