winter sunset from the whale cabin. San Juan Island 2013
For the past week I have been tucked away in a wee cabin (commonly known as the Whale Cabin to those in the know) perched on the west side of San Juan Island. My friend Sharon kindly let's me stay here from time to time; it makes for a great work retreat and the views out over the Juan de Fuca Strait help remind me why I am still slaving away at my PhD (though at times I will admit that the view is distracting!). It's a sea thing, a whale thing. This vast expanse of water ahead of me that is in constant motion and home to such an incredible diversity of creatures. In one word: fascinating. But I digress.
Last winter I spent 3 weeks here at the Whale Cabin writing the first draft of a thesis chapter. This year that chapter has been accepted for publication (cue acceptance dance!) and I have found my way back to the cabin to address my reviewers comments and suggestions. My paper is reporting on the results of my research into the effects of seismic operations on surface-respiration-dive behaviour of bowhead whales(see diagram below); made possible through my access to an incredible database on bowhead behaviour. Most of what we know about bowhead behaviour has been learned from dedicated behavioural observation studies conducted from small aircraft. But how do you study the behaviour of a whale from an aeroplane? I must admit that though I have now spent 3 seasons working on an aerial survey programme for bowhead whales and other Arctic marine mammals, though I have not had the privilege of collecting detailed behavioural data. Conducting systematic line transect surveys to estimate distribution and abundance of whales is quite different to circling for hours over the same area trying to keep tabs on the same whale. Anyone who has tried to follow a whale, dolphin or porpoise from small boats or even from shore have an appreciation of how difficult it is to keep tabs on these animals, let alone manage to measure the time they spend at the surface, how many times they breath and how long they dive for.
Last winter I spent 3 weeks here at the Whale Cabin writing the first draft of a thesis chapter. This year that chapter has been accepted for publication (cue acceptance dance!) and I have found my way back to the cabin to address my reviewers comments and suggestions. My paper is reporting on the results of my research into the effects of seismic operations on surface-respiration-dive behaviour of bowhead whales(see diagram below); made possible through my access to an incredible database on bowhead behaviour. Most of what we know about bowhead behaviour has been learned from dedicated behavioural observation studies conducted from small aircraft. But how do you study the behaviour of a whale from an aeroplane? I must admit that though I have now spent 3 seasons working on an aerial survey programme for bowhead whales and other Arctic marine mammals, though I have not had the privilege of collecting detailed behavioural data. Conducting systematic line transect surveys to estimate distribution and abundance of whales is quite different to circling for hours over the same area trying to keep tabs on the same whale. Anyone who has tried to follow a whale, dolphin or porpoise from small boats or even from shore have an appreciation of how difficult it is to keep tabs on these animals, let alone manage to measure the time they spend at the surface, how many times they breath and how long they dive for.
The main behaviour measures collected for bowhead whales from aerial observation. Illustration by Uko Gorter
Example of spectrogram of bowhead calls
Over the last few days I have been reading and re-reading my doggeared copies of the papers that first described the methods used for bowhead behavioural studies. I have been trying to summarize into one short paragraph how such fine-scale behaviour data were able to be collected from an aircraft circling around whales at an altitude of over 1500 ft. These published papers provide a pretty good account how these data were collected, but it is sometimes hard to imagine yourself in the position of an observer circling over whales somewhere in the central Beaufort Sea 25 years ago. Or so you might think.... unless you find yourself in the online Macaulay acoustic library of the Cornell Lab of Ornithology. Here you can find these incredible recordings of bowhead whales. During the early aerial behavioural observation studies observers also did a really cool thing. They dropped sonobouys (small acoustic transmitter systems) near the whales they were watching. These instruments allowed the observers to record the whales and what the whales were hearing (for example seismic sounds from oil and gas exploration activities). These instruments also recorded audio of the observers on the plane. This means that not only can you listen to the whales you can also listen to the observers collecting their data, noting specifics of a whale, how they identified whales etc.
As I have been working through the revisions to my paper this week I have been listening to these old recordings, imagining what it was like back then, circling over groups of whales for hours at a time. Up to now I have known these whales through numbers in my spreadsheets; but listening to these audio recordings have now brought my spreadsheets to life.
You too can share this experience, simply click the spectrogram to the right and join the aerial observers circling over bowhead whales off the Alaskan coast in the early 1980s.
Till next time..... Thanks!
As I have been working through the revisions to my paper this week I have been listening to these old recordings, imagining what it was like back then, circling over groups of whales for hours at a time. Up to now I have known these whales through numbers in my spreadsheets; but listening to these audio recordings have now brought my spreadsheets to life.
You too can share this experience, simply click the spectrogram to the right and join the aerial observers circling over bowhead whales off the Alaskan coast in the early 1980s.
Till next time..... Thanks!
RSS Feed