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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We finish what we start

6/20/2013

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Last Sunday, with a good dose of stubbornness and not nearly enough training I embarked on 13.1 miles of a very hilly half marathon.  Just 7 weeks prior my friend Meredith asked me if I fancied doing the San Juan half marathon with her.  At that point I had not even run 10 km! But I began to wonder what if? Could I actually do it? I had 6 weeks to train.... So I signed up. Then I decided I was going to use this run to help the American Cetacean Society Puget Sound (ACS-PS) Chapter fundraise for their student travel grants.  There was no going back now.

The student travel grants will be available for students studying cetaceans either at Pacific NW institutions or study cetacean populations in the Pacific NW. The grants will help students with the costs of attending and presenting at the Biennial Marine Mammal conference in New Zealand this December. It may seem like rather odd thing to raise funds for especially as I will not be attending the conference myself but I know from previous years how important these small grants can be.  In 2011 I received an ACS-PS travel grant when I presented my work at the Marine Mammal conference in Tampa. The grant covered my flight, without it I may not have been able to attend. In a short 3 weeks I had received incredible support from my family, friends, fellow students and other marine mammal scientists. We raised enough for two $500 travel grants. Now all that was left to do was to complete the run!

Training was going well; I was even beginning to enjoy getting out for a run after a day in front of my thesis. Then 3 weeks before the race, after my longest run to date, I was limping. A week later there was little improvement and I was beginning to worry... I was not able to train but more importantly I had a 13.1 mile mission just two weeks away! Jean (aka “Motivator Medley” or “Jean the Machine”) my dear friend and training buddy (who routinely kicks my ass while offering the nicest encouragement all at the same time) suggested I go see a physiotherapist. I have learnt to pay attention to Jean’s suggestions....

With instructions to ice, tape, massage and stretch I headed south to San Juan Island. I was still nervous, I hadn’t been able to train at all for 3 weeks! But once my fellow runners, Meredith and Barb turned up and announced that they hadn’t been able to train much either I felt a bit better. At least we were all in the same boat.
PictureAt the start with Meredith and Barbara
The day arrived, with our entry numbers pinned firmly and music selected we made our way over to the county fairgrounds –start and end of the race. Even as we were waiting for the “go” signal the reality of what I was about to attempt hadn’t sunk in. Then we were off.

The San Juan half marathon wove through Friday Harbor before taking us out into the valley on the open road.  It was about half way through town... not even a mile in that the reality of the situation began to sink in. But once out of town there was no turning back. For the first 5 miles Meredith and I jogged along with a couple of girls from Bellingham and a lady from Vancouver. They set a slow and steady pace which meant that by the time we reached the road that would wind us over the west side of the island we still felt great.

It wasn’t long before the first ugly hill reared in front of us, long and steep, it was not fun. Having made it up the hill we continued on past scattered houses, fields, the lavender farm –not yet in bloom and the lake where little boats gather to sail on long summer evenings. We jogged on to meet the road where the full marathoners turned right and we turned left back to town.  From a field on this corner Daniel, as promised, leapt up from behind the hedge to hand us water.

PictureThe long road back to town
We continued on only to face the next big hill, not as steep as before but longer and larger... and what you go up you must inevitably go down.  Running down the hill, steeper on the descent was actually tougher than the ascent (yeah we did walk a bit of the big hill... but frankly we were more than OK with that!), by this point we were approaching mile 8 or 9 and my hips were beginning to ache. Mile 10 came up really quickly... too quickly in fact but I barely noticed (I later found out that the Mile 10 marker had been put in the wrong the place), as I concentrated on trying to keep my pace. We were almost to the home stretch, two more miles left to go and two more substantial hills. A marathon runner from Mexico called Fransico unwittingly got me up one hill by simply distracting me from my aching hips with random chatter. And then the last mile, shortly after the marker Meredith and I turned right leaving Fransico to complete his final 8 miles and we had just one more hill to conquer. And conquer it we did (well almost, we walked a bit of it, it is a really mean hill and even meaner after 12.8 miles!) making it to the top and mustering that last little bit of energy to make a dash for the finish line.

In all it took us 2 hour and 39 minutes to complete the course but what is important is that we finished what we started, and that was the accomplishment in itself. Did I think I had this in me back in April? Not at all! So for me this whole experience has taught me that if you really put your mind to it then you can always finish what you started.
Photos in the post were taken by Meredith Fourre, Barbara Sullivan and Debbie Giles
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My unconventional freedom

6/11/2013

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This past Saturday (8th June) was World Oceans Day.  Rather than spending my day writing something philosophical and insightful about the state of our oceans I was instead writing on an altogether different subject -though a subject that is also close to my heart.
PictureI'm blogging for the Huffington Post!
The story started on Friday when I received a bit of strange text from my friend Tallulah, a local photographer. It went something along the lines of "I have a newspaper editor friend wanting a blog post from a longboarder for the Huffington Post... it has to be done by Monday". My response "I don't really think I'm qualified to talk about longboarding!". As it happens I longboard so that does sort of qualify me and ideas of what I might write began to form. The remit I was given was to write about why I love to longboard and whether the recent accidents involving longboards gave me pause for thought. 

There are many reasons that I love to longboard; I like the slightly offbeatness of it and I like the unconventional freedom that I get from it.  My board provides me an escape from the slog of grad school and the daily routine. Whether I just get out to skate the neighbourhood, the sea wall or further afield to the Seymour
                                                       Demo forest in North Vancouver. So there is no question that I love to longboard.

longboard
After a couple late nights and re-writes (including one on the ferry as I travelled to San Juan Island) I submitted a final draft to Tallulah's editor friend on Monday morning. Less than 24 hours later there I was... well my writing at least, staring at me from my computer screen. Not in a word document but instead on a webpage, the HuffPost Vancouver webpage.

I think I can say that this is my first publication. While it is not the peer reviewed hard core science article that I had envisioned (that publication process takes a whole lot longer than 24 hours!! my paper has been in press now for 3-4 weeks... I have lost count actually), this is no shabby thing. I mean seriously the Huffington Post?? What a weird and wonderful way to start the week!!

Follow this link to read the full article: 
http://www.huffingtonpost.ca/frances-robertson/longboarding-safety_b_3418264.html

Skate safe not stupid folks!!

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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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