Frances C. Robertson
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Sunday Science Something #2

3/9/2014

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The very V behaviours of birds and bowheads

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During the month of November I often see Canada geese flying over the fields of San Juan Island. The birds are flying in the typical V-formation, characteristic of migrating geese. I always had a vague idea that they were flying in these formations in order to save energy or that it had something to do with navigation, but I never really bothered to look into why they fly like this -until a recent article in Nature caught my eye.


The distinctive V-formation is known in a number of bird species and has been the subject of interest and intrigue to scientists and non-scientists alike. A team of researchers from the UK’s Royal Veterinary College travelled to Austria to work with the conservation group Waldrappteam – who work with the Northern Bald Ibis, a highly endangered migratory bird that went extinct in central Europe 300 years ago. Waldrappteam rear these birds and teach them to fly and eventually migrate. This is where one of my favourite wildlife themed movies pops to my mind –yep, you guessed it ‘Fly Away Home’. Guaranteed if I am looking after kids I will make them watch it –and I just admitted that here in public....

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So the birds are taught to fly and then to migrate by following a microtlite (exactly as it was in the movie).   This real-life human led migration has been the first successful one of its kind and has opened up all sorts of great opportunities to study birds in their natural flight –something that was too good an opportunity to pass on for the team from Royal Veterinary College. This opportunity to study the birds’ migratory flight behaviours allowed the research team to investigate why these birds would adopt the V-formation during migrations.
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source: www.rvc.ac.uk
The researchers attached small data-loggers to the birds and recorded behaviours such as when the birds flapped and how hard they were flapping. Working with these trained birds allowed them to retrieve their data-loggers after each flight –something that is mostly impossible with wild birds, and the data they collected has provided new insights into how these birds migrate and why they adopt the distinctive V-formations.


The team discovered that these birds appeared to have keen awareness of the air structures created by their nearby flock-mates, and even more remarkable was that the birds seemed to have an ability to predict or sense the surrounding air patterns and so how to exploit them to their own advantage. 
PictureSource: Nature
The birds would position themselves in the aerodynamically optimum position within the V-formation, i.e. in the best possible place to take advantage of good upward moving air that was being produced by the bird flying ahead.  Upward moving air helps the birds stay aloft without the bird have to exert excess energy through flapping harder.  When a bird flaps it pushes the air down in order to stay up, this creates a downwash of air followed by an upwash of air.  The birds behind the front bird would position themselves where the upward moving air was located –this meant that the birds would not have to flap as hard to stay up so saving energy. The birds were also found to synchronize their flapping behaviour to further exploit the aerodynamic good upwash air.

This video beautifully explains what the research team did and what they found. Watch it! 

So these birds are flying in V-formations to save energy on long migrations. But what do V-formations have to do with bowhead whales? In this case the V-formation is does not assist in the efficiency of the whale’s migration, rather it seems to be an important behavioural adaptation for increasing the efficiency of feeding. 

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Bowhead whales are baleen whales, they feed by filtering tiny marine animals –zooplankton through their baleen fringed mouth. Occasionally whales are seen in groups ranging in size from two to 14 whales swimming in a co-ordinated fashion such that a front “lead” whale is ahead at the front and the other whales are in a staggered lines behind the lead whale creating a V. This formation is also called an echelon formation.

As with the V-formations observed in migrating birds, these echelons are dynamic with whales changing positions, and group sizes changing as whales enter and leave the group. While it is not fully understood how this co-ordinated formation assists with feeding it is thought that whales adopt this behaviour when they are feeding on the shrimp-like crustaceans called euphausiids.
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Euphausiids, unlike other zooplankton species that the slow moving bowhead whale feeds on, exhibit rapid evasive movements and are thought to be able to move out of the way of the whales gape as it moves slowly forward at the sea surface. So those little critters that manage escape the front whale’s mouth by moving to the side find themselves in prime position to be caught up in the gape of the whale behind.... and so on.  

This type of behaviour has also been observed in surface feeding southern right whales. The whales’ adoption of the V-formation ultimately increases their foraging efficiency while at the same time saving energy by drafting behind the lead whale so reducing the cost of swimming, just as the birds exploit the V-formation to exploit the upwash of the bird ahead to save energy during their migrations. So as an energy saving adaptation the V-formation is Very much a winner! 

Feeding bowhead whales. Craig George, NOAA
NOAA photo by Craig George. Three bowhead whales feeding in an echelon formation north of Barrow on large concentrations of krill.
SOURCES:

Portugal, S.J., T.Y. Hubel, J. Fritz, S. Heese, D. Trobe, B. Voelkl, S. Hailes, A.M. Wilson & J.R. Usherwood. 2014.
Upwash exploitation and downwash avoidance by flap phasing in ibis formation flight. Nature 505: 399-402

Waldrappteam http://www.waldrappteam.at/waldrappteam/indexl_en.htm

Würsig B, Dorsey EM, Fraker MA, Payne RS, Richardson WJ (1985) Behavior of bowhead whales, Balaena mysticetus, summering in the Beaufort Sea: A description. Fish Bull 83:357-377

Fish, F.E., K.T. Goetz, D.J. Rugh, & L. Vate Brattström. 2012. Hydrodynamic patterns associated with echelon formation swimming by feeding bowhead whales (Balaena mysticetus). Marine Mammal Science. 29(4): E498-507
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Sunday Science Somethings. Installment #1

2/16/2014

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PictureNenyaki ©2008
It has been an age and a day since I wrote on this blog. I could blame trying to get my thesis finished up (it is on track by the way) or numerous other things. OK, so I am going to blame my thesis after-all because it has been all engrossing and I haven’t really left my computer or thought about much else during this time! 

But I have decided that it is time for me to escape the thesis induced black-hole and re-enter the world of my blog. I do happen to have a plethora of ideas to write on –the issues surrounding self-promotion in science or last month’s Alaska Marine Science Symposium, and minke whales could always do with more attention. But instead I have decided to start a series of blog posts entitled “Sunday Science Somethings”. I have adapted and borrowed the Sunday Something idea from my sister, who wrote a fun blog about all things pretty and beautiful. My adaptation will also talk about beautiful things, however, you will have to expand your definition of beautiful because I plan to share amazing, exciting, and fun science stories –most of which I suspect will be marine focused as that is my thing. But science itself is a beautiful thing so borrowing the title from my sister’s blog on beautiful things seemed appropriate –and as an added bonus she is happy to let me use it!

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This week has been full of fun, fascinating and significant science. Many scientists, science communicators and journalists converged on Chicago for the Annual American Association for the Advancement of Science (AAAS ) this week. My twitter feed has been filled with all sorts of interesting snippets’ –you can check some of these out by looking up #aaasmtg. But for me the most exciting science story to come up this week was that of study that has shown how it is possible to count whales from space. Yes, I did just write “count whales from space”.  In fact the paper, published in PLoS One this week is entitled just that: Whales from Space: Counting  southern right whales by satellite. 

This might seem like a completely outlandish exercise to many, who on earth thought one could count whales from space? But as I saw links to the article appear in my twitter and facebook feeds and the story highlighted by the likes of the BBC, I remembered the time I was checking out the Beaufort Sea with Google Earth –I had a short lived moment of over excitement as I discovered what I thought was a whale’s tail fluke.... on a closer inspection in turned out to be boat.  Needless to say the fact that scientists have now been able to show that high resolution satellite imagery (obviously Google Earth is not quite high tech enough. Yet.) can be used to count whales is utterly cool and I feel just a little bit vindicated for my Google Earth “discovery”. 

So how is it possible to count whales from space? And what are the practical uses for such methods? Or is it all just a bit of a news grabbing gimmick? First off, this is far from a gimmick. The implications for such a tool are widespread for both management and conservation of large whales. The methods presented in the paper provide the first successful attempt to use satellite imagery to count whales at and near the sea surface. Additionally, the authors attempts at automation means that whale counts can be made relatively efficiently and, importantly more quickly. The ability of this tool to help assess large areas for the presence of whales will provide an attractive alternative to the costly and risky aerial or vessel based surveys that are currently used for this purpose.
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Figure 2 from Fretwell et al. 2014. A selection probable whales found by automated analysis.
One of the reasons that I am so excited about this paper is because I can see the potential for using satellite imagery to count whales in areas that are subject to human activities –such as oil and gas activities or commercial shipping. While this approach would not be an effective tool for real-time mitigation it could provide useful for baseline data on the presence of large whales in coastal areas subject to these human activities. 

As with aerial surveys the methods presented in this paper can only count whales that are at or near the surface and so will always be subject to a bias –because whales only spend a small proportion of their at the surface. But with an understanding of how much time whales spend at the surface and how long they dive for we can try to overcome this bias. For aerial and ship based sightings this is achieved by calculating correction factors –essentially these are the probability that a whale will be at the surface when that patch of sea surface is in view of an observer. The number of whales detected in the survey –or image is then multiplied by this correction factor to give a better estimate of how many whales are actually present in the area.    My thesis work has developed availability correction factors for aerial surveys that are recording bowhead whales in the Beaufort Sea and these methods could also be adapted to help correct the counts of whales achieved through the use satellite imagery. Essentially this idea of counting whales from space is advancing aerial survey techniques into the next sphere... the exosphere and even beyond that into space. 
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Bowhead whale in the Beaufort Sea. NOAA Marine mammal surveys 2012
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Searching for the big blue.

8/1/2013

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This summer I finally got the opportunity to spend a week with a group of researchers in San Diego. Mari Smultea and Bernd Würsig have been bringing a small team to San Diego since 2009 to fly aerial surveys off the coast of San Diego in order to collect baseline data on the distribution, density and behaviour of marine mammals.  
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Project lead, Mari Smultea

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Cloudy skies
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me, happy to be observing
Mari invited me to join them for their final survey of 2013 so that I could have the opportunity to learn about how cetacean behaviour data are collected from aircraft.  Mari and I are both working with these types of data for our doctoral research, but unlike Mari I have not yet had the opportunity to see first-hand how behaviour data are collected from the air because my data mostly collected in the 1980s. So when Mari emailed to see if I wanted to join her and the team this July I jumped at the chance. Not only would I get to fly with Bernd Würsig –a leading expert in the study of cetacean behaviour and who was the first to define the different bowhead whale behaviours and collected the bowhead behavioural data that I have been using in my research, but this was my second chance this year to see the blue whale. The largest animal to have ever lived on this planet.

If you have read my earlier posts you may remember that my first real attempt to see a blue whale was back in April when I went out on a whale watch trip in Monterrey Bay. This quest was scuppered by killer whales. But this time round in San Diego my chances were better, or so Mari assured me. I was optimistic, especially after the team returned from their first flight of the survey to report that the blue whales were around just off the coast of San Diego. They came back that first afternoon having seen a number of blues that meant they were able to conduct focal follows on at least 2 whales.  
Dr. Bernd WürsigDr. Bernd Würsig observing from the plane
To conduct a focal the team will circle the whale from an altitude of 1500 ft if cloud conditions allow. They record the behaviour of the whale including the time it blows, when the tail is seen to rise out of the water –known as fluking, the time the whale dives and how long it dives out of sight for, which direction the whale is headed in, how fast it is moving and the general activity state of the whale (e.g., travelling , foraging or resting). All these data are recorded onto audio and video recorders and the whale is photographed as well. Later, these data are transcribed and scrutinized to ensure that everything is entered into the survey database.

For the first part of the survey I was able to help the team with various data tasks including examining sets of photographs collected during focal follows on the blue whales seen.  Mari and Bernd were keen to confirm that a whale observed during an hour long observation session was indeed the same whale.  I poured through photo after photo from three photo sessions that had been taken during the focal follow looking for a scratch or scar that would make matching the photos possible.  Then there it was a ding on the left shoulder of the whale –a scar likely resulting from a cookie cutter shark. I was able to match photos from each of the photo sessions confirming that they had indeed been circling over the same whale. By the end of the second day of the survey I had performed photo-ID on a blue whale from photos taken at more than 1000 ft but I still had not seen a blue whale in person.

The next day I got to fly. It was a short training flight and though I was optimistic we did not find any blue whales. We flew again the next day and saw many mola mola, common dolphins and even a group of bottlenose dolphins, but still no blue. The fifth day of the survey dawned, again the weather was not promising, but there was less cloud that the day before. We set off  to search for blue whales along the coast. Again we saw lots of mola mola and common dolphin but no blues. Heading south towards the border with Mexico we saw more common dolphins, circling groups to confirm species, estimate school sizes and document behaviours. We observed interesting behaviours such as synchronized upside down swimming followed by rapid darting manoeuvres in different directions.  We saw groups of three to six dolphins do this at a time while in front of the main school.  This behaviour was indicative of foraging –the dolphins appeared to corralling and chasing fish.

As we continued on we saw a group of Risso’s dolphins; Mari is studying the behaviour of these dolphins for her PhD and has observed Risso’s with other dolphin and whale species.  This time we saw them alone but were able to observe apparent social behaviours and surface active behaviours. These dolphins are much larger than common dolphins and very light in color due to the scaring that covers their bodies, not much is known about them in the Pacific so these surveys provide a unique opportunity to study them.  
We continued on our search for blue whales, following the edges of undersea canyons. We slowly made our way out to San Clemente Island and picked up more dolphins. Suddenly Bernd called out “whale”! Was this going to be my first blue? I saw the large rostrum of a baleen whale disappear beneath the surface –we circled back to pick it up as it surfaced but 12 minutes later there was still no sign of the whale. We continued on our way left wondering whether the whale had been a fin, sei or Bryde's whale. There was only one more day left on the survey and I was beginning to wonder if I really was going see to blue whale. Had I been slunk again?

We turned back for San Diego. Then there it was. A blue whale hanging there, seemingly suspended just below the surface. The whale glowed a beautiful turquoise blue color in the water. As we circled to document the sighting, my eyes were glued to the whale, watching and waiting for it to rise to the surface and blow. It hung there still, barley moving, then as the pilots turned back towards our track-line the whale rose majestically to the surface and blew. I watched the blue whale disappear out of view behind the plane. I had finally seen a blue whale and the image of this magnificent great whale hanging so gently below the surface was burned into my memory. 
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The final day of the survey resulted in 155 sighting in 4 hours, common dolphins, California sea lions chasing bait balls, mola mola, and more Risso’s dolphins, we didn't see any more whales despite almost perfect sighting conditions but I was happy, I had seen and learnt so much, worked with a great team of people and above all I had finally seen a blue whale. 
Blue whale fluke
Blue whale fluke breaking the surface
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Surveying for marine mammals in the Beaufort Sea

7/5/2013

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This time last year I was on standby. I was awaiting the call to head north to Alaska to join my aerial survey team. This year I am not on standby because I am not heading north and I am more than a little melancholy about it. Alaska, the Arctic has a way of getting under your skin. I’m really not sure why this happens, especially as I am always stationed in Prudhoe Bay – the largest oil field in the US. Instead I am spending the summer at my desk working to finish my thesis, and wondering what I would have seen had we been up there flying surveys this summer.
Last year, in late August, after about 6 weeks of standby, I finally found myself making the trek to Alaska’s north coast, to participate in aerial survey work in the Beaufort Sea.  This time I was co-leading an aerial survey team of Protected Species Observers (PSOs) whose purpose was to monitor and record marine mammals in the vicinity of drilling operations in the Beaufort Sea.

This work provides me with valuable field and professional leadership skills as well as a means to fund my way through my PhD. Although this was my third field season in the Arctic, I know that no two seasons are ever the same; there are always new learning experiences to ensure that surveys are successful and good data is collected.  But most of all there are always new sighting experiences to remember, whether it be a breaching bowhead or evidence of a recent polar bear kill on the ice.

aerial survey
Marine mammal aerial surveys
I was based in Deadhorse, Prudhoe Bay, perched on Alaska’s North Slope. With its gravel roads and trucks, it is an industrial hive serving the largest oil field in the US, floating on gravel pads atop the Arctic tundra. This is not your typical remote field work experience. The real experience begins when I board the survey plane, a sturdy de Havilland Twin Otter, specifically outfitted with specialized bubble windows for the purpose of marine mammal surveys.  We fly a series of pre-determined transects perpendicular to the coast recording all marine mammals that we see, but we are particularly interested in seeing  bowhead whales.

Deadhorse
Deadhorse, Alaska
As observers we continually scan the water searching for marine mammals and noting environmental conditions. In the Beaufort Sea, the species that are most often recorded are bowhead and beluga whales, bearded and ringed seals, and polar bears. When an animal is sighted on transect, we record   relevant details (“one adult bowhead, swimming at medium speed, travelling in a 10 o’clock direction”) and take an angle measurement to allow its exact position to be calculated. On some transects we may see a lot, while on others we not see anything at all. We survey for almost 5 hours –limited by the fuel capacity of our survey plane.

After our surveys we return to our base in Deadhorse for an evening of data entry and report writing.  We never know when we will be able to survey next due to the changeable nature of the weather on the slope. But we always hope that conditions will remain clear and the winds calm to allow surveys the following day.

Beaufort Sea
The Beaufort Sea
My PhD research focuses on how bowhead behavioural responses to industry operations influence the ability of aerial observers to detect whales; and how this may impact density estimates of whales in the vicinity of offshore industry activities. Working on these surveys provides me with first-hand experience and a better understanding of the data that I use in my research.
Deadhorse
Deadhorse, blanketed by snow
Our surveys continued through September and October, coming to an end in early November. The colors of the tundra changed as summer advanced into autumn and autumn into winter.  Ice formed over the ocean and the bowhead migration had all but passed through our survey area.  Daylight hours waned and storms blew through bringing snow that blanketed Deadhorse; the survey season ended for another year and I headed back to BC to continue with my studies and wonder if I would be heading north again this year. 

As it turned out industry activities in the Beaufort Sea were scaled back this year and there was no requirement for an aerial survey monitoring crew. My thesis will probably be thankful, but I will still miss flying out over the tundra, watching the colors change as the season progresses and as ever catching a glimpse of the migrating bowhead whale.

Shell, Alaska produced a pamphlet on marine mammal research in the Alaskan Arctic -includes our aerial survey work
Marine Mammals of the Chukchi and Beaufort Seas
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The case of the two-stepping minke

6/2/2013

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It’s a Saturday night. Yet, here I am at my desk with a list of thesis stuff as long as my arm staring at me. Trouble is reading about 2-step Generalized Additive Models just isn’t appealing on a Saturday night.  This morning I had grand plans to write a blog post about why I think the BC Liberal government rejected the Enbridge Pipeline proposal... but a case of political posturing sort of lost my interest as the day progressed; there will be many more opportunities to write about this as industrial development along BC’s coast is not going away – whether it be Enbridge’s pipeline or the Liberal’s grand Liquefied Natural Gas plans.   Instead, on a chiding from my friend Jonathan Stern I have decided to write about minke whales – and more precisely the case of the two-stepping minke.
minke chin
minke chin. F.C. Robertson. NMFS permit # 4481856
It has been awhile since I sat down to write about minke whales, but I think about them often. The whale watch season in the Salish Sea has just begun and with it come reports of minke encounters. Photos of these encounters have been appearing in my facebook stream; triggering memories of my own encounters with these little whales over the years. My first encounters with minke whales were back in 2005 when I joined a minke whale research project.  Those first weeks made such an impression that I returned to the project for three more summers, learning to photo-id the whales and collect behavioural data on their foraging habits.

So what is so special about minke whales? Most folk overlook them for being common, being those whales that are the target of Japanese, Norwegian and Icelandic whaling activities. True they are still hunted, and in some parts of the world are they are extremely abundant but here in the Pacific Northwest minke whales are rare. Yes they are rare. In fact NMFS is now reporting fewer than 600 whales in California, Oregon and Washington State waters. So let me say this again... minke whales on this coast are rare. If you see one please report it and then have a little dance party because you just had an encounter with a super cool rare whale! No I’m serious... just don’t fall overboard in your excitement because the water here is really really cold! So this is partly why I think these little whales are so special.
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F.C. Robertson NMFS permit #4481856
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minke whale. F.C. Robertson NMFS permit #4481856
The Salish Sea happens to be what we call a hot spot for minkes. Whales can be consistently found on the banks off the south end of San Jaun Island, e.g., Salmon Bank and Hein Bank during the spring and summer months. In the 1980s they could also be found inside the islands, in fact their presence was so predictable that the waters between Waldron and Stuart Island was referred to as “minke lake”, and it is to this day though you rarely see a minke in ‘minke lake’ these days.

Our ability to photo-id minke whales has provided a foundation from which we can conduct foraging studies through focal follows. You sort of have to know that you are following the same whale for a successful focal follow.... But the data we collect from these focal follows tells us a thing or two about these critters that isn’t so obvious to the casual observer. In fact minke whales tend to frustrate the casual observer due to their unpredictable surfacing behaviour. You never quite know where the whale will come up next or, if indeed the whale will come up! But if you have the patience (this is a pre-requisite of the minke project) you can follow these animals for sometimes hours at a time.
The data collected during a focal follow provides information on feeding rates and foraging strategies, the photo-id data gives us an idea of how many individuals are using an area and whether they use the same area in consecutive years. Having data on individuals from multiple years also allows us to look at whether foraging behaviours have changed between years. 

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lunge feeding with side roll. NMFS permit #4481856
Changes in foraging behaviour may be the result of changes in their prey’s behaviour or perhaps a shift in the main prey base. In the Salish Sea minke whales feed on bait fish, e.g., juvenile herring. In recent years we have observed changes in the way that both birds and minke whales are feeding so could this be due to a change in the main forage fish composition of the area? The insights that we gain into minke whale feeding ecology are a stepping stone to understanding the local marine ecosystem.
I am sure by now you are wondering why I titled this post “The case of two-stepping minke”; sitting down to write about minke whales brings back memories of my experiences with the minke project. Most revolve around floating in our small research boat on Hein Bank waiting for our whale to pop up again. Listening for its breath and scanning 360 degrees searching for that tell-tale disturbance in the water’s surface as the smooth dark back breaks the surface.  In a way their surfacing patterns remind me more of a dance but in reality these whales are always two steps ahead of us leading us off in random dances across the banks, a little whale in constant search of the little fish.
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Taken back in time to the bowhead behavioural studies of the 1980s

2/22/2013

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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.  

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The main behaviour measures collected for bowhead whales from aerial observation. Illustration by Uko Gorter
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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!

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A LONG WINTER SONG

8/28/2012

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copyright A. Foote 2011 Qeqertarsuaq Bowhead whale research

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
Picture
Photo copyright Martha Holmes/NPL
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
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Will they, won't they?  Who will get what at this years 64th IWC meeting?

7/3/2012

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This is the week of the 64th IWC (International Whaling Commission) meeting, held this year in Panama City.  Delegates from ~63 countries are present to discuss and vote on a series of proposals that are due to be put forward this week, while countless representatives from NGOs all over the world are present to witness and report on the proceedings as well as to lobby delegates for the continued protection and conservation of whales and small cetaceans around the world.

During this intense 5 day meeting (of which we are on Day 2) a number of key items will be up for vote, some of them for a second attempt.  One such proposal is that of the South American countries for a South Atlantic Whale Sanctuary.  This is the second attempt to introduce this proposal and unfortunately yesterday the vote failed to achieve a 2/3 majority.   Other key issues that are on the table include the Aboriginal Subsistence Whaling quotas, that include those of the bowhead whale for the Alaskan Inupiat and Russian subsistence groups.  The US have been fighting hard to get these quotas approved and many would argue have resorted to some interesting politics to obtain the support of Japan.  However, it is not news that the politics of the IWC is interesting to say the least!  But I have only brushed the surface and the week is packed with items including whale-watching, small cetacean conservation, ship strikes, small type coastal whaling (this one is of keen interest to the Japanese), the revised management plan and many more.

The IWC website has provided access to the meetings schedule as well as key reports of the scientific committee (that met in the weeks prior to this 64th meeting).  http://iwcoffice.org/meetings/meeting2012.htm

Another good source of information from an NGOs perspective is the ACS (American Cetacean Society).  Cheryl McCormick (Executive Director of the ACS) is currently at the IWC meeting in Panama and actively blogging, posting detailed reports of the proceedings (often with a rather witty slant).  Check out her blog 'IWC: The World is Watching!'

I will post a summary of this weeks events in Panama early next week and highlight the key developments and outcomes.  I'll also save and post any interesting news articles that I find related to this years' meeting. 

Cheers
F

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Rio +20 - An international opportunity to protect our oceans.

6/13/2012

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Oceans Inc. A multimedia channel dedicated to the sharing news about our oceans will be broadcasting from this years Rio +20.  The UN conference on sustainable development brings global leaders and representatives from around the world.  This video has been produced by the Pew Environmental Group and the Zoological Society of London to tell us why global leaders should seize this opportunity for action to protect our oceans.

Dr. Alexis Rogers gives an overview on some of the solutions to key problems currently affecting the oceans today
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To shift a ship for a whale

11/6/2011

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switchboard.nrdc.org Spot the feeding blue whale!
Since 2008 ship-strike related research has been conducted off the coast of California, specifically in response to concerns regarding the impact of shipping on feeding blue whales.  This research has been a collaborative effort, carried out by non-profit groups such as Cascadia Research Collective, academic institutes, government agencies and the office of Navel Research.  The data derived from tagging and observational studies has allowed scientists to better understand the interaction between feeding whales and ships, however, I won't go into the details here, rather I encourage you to check out the links I have posted at the end of this post.. 

The really cool thing that I want to highlight is the recent announcement that the US Coastguard has recommended shifting the shipping lanes in the Santa Barbara Channel.  By shifting the shipping lanes cargo ships will be moved away from feeding whales and therefore reduce the risk of ship-stike. To see the fruits of one's research culminate in a change of management strategy is perhaps what every scientist involved in a study such as this strives for.  It must certainly be gratifying to know that your findings have directly helped to reduce the risks that our activities have on other creatures in the ocean, and also elsewhere.  I know that this is certainly something that I strive for with my own work.

Further information on this research can be found in this nice summary document posted by Cascadia Research:
Summary of ship-strike related research on blue whales in 2011

The Coastguard recommendation can be found at:
http://latimesblogs.latimes.com/files/la-lb-pars-notice-11-1-11.pdf

And some media articles related to this issues include:
The LA Times
San Francisco Chronicle
ACS Online Journal



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    I am a wildlife biologist and I have a fascination with the marine environment and particularly whales.  I work to understand our impacts on the marine environment and how our work as scientists can facilitate better management that aims to reduce the effects of human activities on marine species and their environment. 

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