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Some people work in cubicles, others work in kitchens, but the most intriguing workplace of all may be the coast. Meet the people who head to the ocean instead of the office in our Coastal Jobs series.
Nadine Stewart Lysiak is an assistant professor of marine ecology at Suffolk University in Boston, Massachusetts. She analyzes compounds in the baleen of critically endangered North Atlantic right whales to help figure out where the animals migrate, why they’re reproducing so infrequently, and how traumatic events like gear entanglements could be accelerating the species’ decline.
Baleen is difficult to get out of a right whale’s jaw. It’s embedded in the skull, and the gum tissue is very strong. Our colleagues working on whale necropsies do amazing work to maneuver it out. Then they wrap it in trash bags and send it to me and my research colleagues in Boston.
Like fingernails, baleen is made of keratin and stores biological information. The last 10 years of a whale’s life is recorded through the stable isotopes and hormone levels captured in its baleen plates. We get isotopes from what we eat; because large whales migrate over extensive geographic areas with different food sources containing different isotope ratios, we can figure out where they’ve been. And measuring the hormones in baleen can tell us if and when a whale was pregnant and what its stress levels were during a traumatic event.
When we receive a sample, it’s usually very oily and dirty with decomposing body tissue and sand. We first clean the baleen plate, then we drill into it at two-centimeter intervals down its length to make powder. For isotope testing, we put a milligram of powder into tiny capsules and send them to a lab where they’re measured in a mass spectrometer. We measure concentrations of progesterone, testosterone, and the stress hormone cortisol in a lab at the Anderson Cabot Center for Ocean Life at the New England Aquarium.
The fact that right whales are one of the best studied wild animal populations in the world is very important because it gives us more power in interpreting our numbers. We have data on where individual whales have been over a year, and we know their age and some of their reproductive history. So we can compare isotope or hormone values to what we already know.
One of our goals is to understand right whale calving rates. The intervals between births are much longer than they should be—10 years for some individuals instead of about three. The species isn’t reproducing enough to recover. We need to understand why before we can solve the problem. If stress from noise, fishing gear entanglement, or nutritional deficits is reducing fertility, for example, that might require a different solution than if the key issue is that calves are dying preterm or soon after birth.
Another important part of our work right now is quantifying the stress response to entanglement to better understand the physiological impact of entanglement and why it is a threat to whale survival. In some animals, we’re seeing orders of magnitude increases in cortisol at the end of their life, which can indicate they suffered from entanglement or another trauma. Approximately 80 percent of the right whale population has been entangled at least once, and we have evidence that it impacts development and can even make the whale more vulnerable to something like a ship strike.
I don’t even think we’ve scratched the surface of what you can measure in baleen. You can’t get this much continuous information from a wild animal any other way. It’s just the miraculous nature of this tissue.