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.  

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!

Have I mentioned how lucky I am to have been given the chance to study such a fascinating creature for my PhD? Well if not here are a few tidbits why. The bowhead whale, weighing in at around 120,000 lbs and growing to as much as 60 ft is the only mysticete whale to have evolved to live year round in the icy Arctic.  And while this animals' impressive life span - estimated to be up to (and perhaps beyond) 200 years consistently cause jaws to drop a lesser known, and I think perhaps, an equally impressive characteristic of this whale surround it's acoustic abilities.

Yes whales produce sound; it is how they communicate. Large mysticetes tend to make rather odd moaning sounds of very low frequency and it is generally well known that male humpback whales sing intricate songs during the winter breeding seasons in a bid to attract females.  If you ever find yourself in Hawaii' during the months of January and February try sticking your head under the sea - you will hear the chorus from male humpbacks.  Research has confirmed that it is only the males that sing and for those that are aware that whales singing most only know about singing from humpbacks. But here they are wrong, oh so wrong.  The bowhead whale is a singer too, in fact at times this rotund cold water creature could arguably rival the humpbacks singing ability.... or at least that is what I like to think.

Yet we know so little about the song of the bowhead whale, who is the singer? Is it just males that sing, as is the case with humpback whales or do females sing too? Why do these whales sing? are they singing for a mate? Bowheads in the Western Arctic have been recorded singing during the eastward spring migration and it is thought that these songs are the leftovers of much more active singing over the winter months.  It is also suggested that singing is a method of maintaining connections between migrating groups.  Bowheads in Disko Bay (off Western Greenland) have also been recorded to sing and songs are much more complex in the winter than than during the spring.  But over the winter of 2008/2009 the crème de la crème of bowhead song was recorded and more exciting the 60 plus complex songs were recorded in the Fram Strait (to the east of Greeenland).  The whales in this area are part of what is known as the Spitsbergen Stock.  This stock of whales, once the largest of the bowhead stocks was the first to be targeted by commercial whalers as early as 1600 and were reduced to near extinction by early 1800. 

The University of Washington researchers did not expect to get much from their 2 recording devices. But boy were they wrong.  Between November 2008 and April 2009 the device located in the Western Fram Strait recorded whale songs nearly every hour and over 60 unique song patterns were detected. The authors of the this study (published in Endangered Species Research this year ) commented on the remarkable nature of such a diverse repertoire that approaches song birds rather than whales.  The study also found that singing peeked with the lowest water temperatures, when ice conditions were most dense and while is was almost completely dark.  The extent of the singing has suggested this population may be larger than previously thought and if bowheads do only sing during the breeding season then these recordings have provided some evidence of an active breeding part of this critically endangered population, which is always good news!

Research Article, freely available:
Stafford, K.M., S.E.Moore, C.L. Berchok, Ø. Wiig, C. Lydersen, E. Hansen, D. Kalmback and K.M. Korvacs. 2012.
Spitsbergen's endangered bowhead whales sing through the Polar night. Endangered Species Research. 18(95-103)

Examples of the Bowhead songs:
(These examples are available on the University of Washington Office of News and Information website)
Song 1
Song 2

LINKS
These links take you to some of the press coverage, I have been a bit late in posting about this story but it is still so exciting that I think it continues to be worth sharing. Plus it is another reason for me to share with you why these whales are so fascinating.
Critically endangered whales sing like birds; new recordings hint at rebound (University of Washington)
Study: Chatty Arctic Bowhead whales sing like the birds (Alaska Dispatch)
Critically Endangered Whales Sing Like Birds; New Recordings Hint at Rebound (Science Daily)

Western Greenland Bowhead Acoustic Research:
http://diskobayarcticstation.wordpress.com/bowhead-whales/bowhead-whale-biology/

The North Slope Borough, Alaska: Bowhead studies and other bowhead sources
http://www.north-slope.org/departments/wildlife/Bowhead%20Whales.php