One of our newest research projects is a pilot study to see if it is possible to collect respiratory vapor ("blow") from free-swimming North Atlantic right whales, and then to see if we can measure stress hormones in it.
But first: why are we trying to measure hormones in whale blow? To give a little background, one of the most urgent needs in marine mammal research today (in my opinion, anyway) is that we really need a good way of measuring stress hormones in free-swimming whales. I've been measuring stress hormones in terrestrial wildlife for most of my career, and time and again I've found that that if you have a good method of measuring stress hormones, you have a good chance of figuring out whether or not certain human activities are seriously affecting the animals.
For example, whales worldwide are being affected these days by a huge variety of disturbances, ranging from noise (shipping traffic, sonar, seismic exploration), to global climate change, to direct physical effects like net entanglement and ship strikes. Some of these disturbances are obviously bad for the animals. An entangled whale, for example, is very obviously in trouble. But what about the disturbances that have subtler effects? It's not always so easy to figure out whether, or how much, certain disturbances might be affecting the animals. Take shipping noise, for example. Suppose a population of whales is subjected so much shipping noise that (say) the whales fall silent, apparently unable to hear each other; or maybe they move away, leaving a preferred feeding ground and moving to a less preferred feeding ground. Those responses might look rather minor. But sometimes the animals actually turn to be highly stressed by such impacts, to such a degree that their health and reproduction starts to suffer. Eventually, the whole population can start to go downhill.
The good news is that these subtle effects are very often detectable early on, via elevations in the animals' stress hormones. So, if we could develop a way of measuring stress hormones in whales, we could potentially finally have a good method to detect, assess, and hopefully ameliorate, the stressful impacts of human activities - before the impacts get too severe.
So, that's why we want to be able to measure stress hormones in whales. There's a fundamental problem, though: Most hormone techniques require blood samples, and it's basically impossible to get a blood sample from free-swimming whale. So we have to try to get some other kind of sample from the whale instead.
A North Atlantic right whale's distinctive V-shaped blow.
Photo: Jessica Taylor
We've already found that we can measure stress hormones very well in whale feces, and we have several other research projects focused on fecal stress hormones. But unfortunately, not all whales are thoughtful enough to provide a fecal sample when we want one! Enter respiratory sampling. If you spend any amount of time watching large whales, you'll know that every whale, every time it surfaces, produce a big, puffy cloud of respiratory vapor. When you're watching a whale, usually it does not happen to produce a fecal sample when you're nearby, but it always blows. Repeatedly. In fact, these "blow" clouds are so big and visible that they're often how we spot and find the whale in the first place (as in, "Thar she blows!"). A few researchers have already succeeded in collecting tiny amounts of blow vapor, and one of our colleagues even found some hormones (testosterone and progesterone) in a few of her blow samples.
What we want to do now is develop a method to collect larger volumes of blow, enough so that we could try to measure several different hormones at once - including the first-ever attempt to measure stress hormones in whale blow.
ps- stay tuned for Chapter 2!