Skip to content

Ecology Doctoral Student Analyzes Whales’ Baleen to Reconstruct the Story of a Species

What can a fin whale’s feeding apparatus tell us about that animal? William Cioffi, a Ph.D. student in Ecology, took a summer course at the University of Utah on stable isotope ecology to support his dissertation on using baleen from fin whales to reconstruct individual life histories and assess changes in foraging ecology, reproduction, and stress.

He was among 18 Duke University students who received Graduate Student Training Enhancement Grants (GSTEG) in 2017-18 from the Office of the Vice Provost for Interdisciplinary Studies for training beyond their core disciplines. His faculty mentor is Andrew Read. He shared an update:

A man looks at an animal

The GSTEG award provided me with support to attend a 10-day workshop on stable isotope ecology at the University of Utah this past summer. In addition to morning and evening lectures by top experts in the field, we spent afternoons collecting samples from around Salt Lake City and then processing and analyzing them in the laboratory.

We learned a great deal about the history and theory behind stable isotope ecology as well as many laboratory and analysis techniques that have already been useful to me in my work. Most exciting about this course was the opportunity to discuss ideas and challenges with other students and instructors who had all spent a great deal of time thinking about these issues. The participants included those studying vertebrates, geology, botany, and even forensic science. This course has been running for over 20 years and everyone benefited from the great experience of the instructors and former students, some of whom have even returned as instructors themselves.

In my own work, I use stable isotopes to investigate the historical ecology of baleen whales. Baleen whales are named for the keratin plates that comprise their feeding apparatus. These plates grow continuously throughout an animal’s life, slowly wearing away at the distal end. By repeatedly sampling for stable isotope analysis along the growth axis of an individual plate, a time series can be generated that provides information about foraging and migratory behavior that might have been occurring when that part of the plate was growing. These data provide a window into the past for populations that may no longer exist, but for which baleen plates have been archived in museums or other collections.


This internal funding mechanism from the Office of the Vice Provost for Interdisciplinary Studies encourages doctoral and master’s students to step away from their core research and training to acquire skills, knowledge, or co-curricular experiences that will give them new perspectives on their research agendas. Graduate Student Training Enhancement Grants are intended to deepen preparation for academic positions and other career trajectories.

Images: 2017 IsoCamp class; William Cioffi photographing baleen in preparation for sampling at the New York State Museum