Tag Archives: Biology

New Video: The Dolphin and the Sound

As you know, I’m fortunate enough to be sister to the amazing wildlife film-maker Lisa Marley.  I’ve written about her documentary on Scottish raptor poisonings here previously (and incidentally, this work is currently touring the film festivals – scroll to the end for details!).  But in June, we actually worked together on a short film project as part of the Aquatic Noise 2016 conference I attended in Dublin.

The conference held a public evening involving short lectures around the theme of underwater noise, and also invited submission of videos on this topic.  Lisa and I worked together to create a short film describing the effects of human noise on coastal dolphins, similar to the idea of my 3MT speech – but with much cooler visuals than just me standing on a stage!

I wonder if anyone recognises the locations involved in this production?  Suggestions on a postcard please…!

So now I have a professional video to highlight my research AND had the awesome experience of working on a creative project with my sister.  And all without a single sibling squabble to be seen!


“Red Sky on the Black Isle” lastest screenings:

  • Hebrides International Film Festival (on Lewis, Harris, Uist and Barra; UK):  14-17 September 2016
  • Aberdeen Film Festival (UK):  17 October 2016
  • Festival de Menigoute (France):  27 October 2016

Follow the film’s Facebook page for more updates!

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New Paper: Fish Choruses in Darwin Harbour

ICES Journal ArticleAs well as working on my PhD, I’m also lucky enough to be involved in other projects at the Centre for Marine Science and Technology (CMST) from time-to-time.  Now the results from one of these projects have been published in the ICES Journal of Marine Science.

A couple of years ago, I was asked to review acoustic data from Darwin Harbour, in the Northern Territory of Australia.  I’ve written before about the variety of sounds produced by fish, and in the Darwin data we found oodles of different fish choruses.  Fish sounds can be species and size specific, and such en masse sound production often has behavioural associations, for example by corresponding with feeding or reproduction.

So there is a lot of information to be gained by listening in on fish!

In this paper, we recorded nine different types of fish choruses and investigate their patterns of occurrence.  Environmental conditions such as lunar patterns, time of sunset, temperature, tidal information and salinity levels all contributed to the context of when particular choruses were heard.  These results are useful not only to scientists but also to fisheries managers, as it provides improved knowledge regarding species distribution, fish habitat-use, identifies spawning seasons, and monitors behaviour.  Which, when you can’t see fish below the surface, is often difficult data to collect!

The full paper (doi: 10.1093/icesjms/fsw037) is available here.

Why statistics is not “just maths”

Stats are comingEarlier today, a colleague and I were talking about a paper that we’re working on regarding fish acoustics.  He was asking if I would have time to do some statistical modelling of presence in regard to several environmental variables, and I hinted that I am a bit time-poor at the moment.  While we were discussing who else in the department could help with the statistics, I rattled off a fellow PhD student’s name.

What, them?  But they doesn’t know how to do programming!” said my physics-, engineering-, maths-background colleague in dismay.

But it’s not programming as you think of it,” I replied.  “It’s statistics.

*sarcastic look*

What’s the difference?” he asked.

Well, the answer is that there is a pretty big difference…

Theory vs. Applied

When I was at secondary school, in our final year we had the choice of choosing Advanced Mathematics or Applied Mathematics (aka statistics).

The Advanced Mathematics course taught you how to “select and apply complex mathematical techniques in a variety of mathematical situations”.  This included units such as algebra, calculus, geometry, and equations.

The Applied Mathematics (Statistics) course taught how to “make sense of inherent natural variation in a wide variety of contexts through the collection, analysis and interpretation of data”.  This included units such as hypothesis testing, data analysis, data modelling, and statistical inference.

So basically, one course gave you a year of studying complex, in-depth equations and formulas whilst the other course gave you a year of mathematical problem-solving.  By that time I had already been accepted into studying Zoology, so was strongly encouraged to take this opportunity to get familiar with statistics.  The justification was that it would give me a head-start before I started using statistics in my research later on.

one-does-not-simply-pass-statisticsOf course, the fact that I spectacularly failed the course has nothing to do with anything.  Although in fairness, we started with a class of 30 and were swiftly whittled down to a class of 3 when the other students realised what a true form of hell statistics really are.  Many of them transferred to the Advanced Maths class instead, because they thought it was easier.  And despite my overall grade, it did in fact give me a head-start when I started studying statistics at a university level since most students had never touched the subject before.

As an added bonus, it means I can now also honestly say that you don’t need to pass Maths in high school to succeed in science.  However, this does make me rather unpopular with parents at University Open Days, and as a result I’m generally discouraged from attending…

Fear of statistics – or fear of maths?

Most biologists recoil in horror at the mere thought of statistics. Some less-kind scientists suggest that this is why biologists are studying biology and not a ‘hard’ science like physics.  However, the truth is that most physicists would recoil in horror from the idea of statistics too – if only they had to use them.  But their work is often better captured by the mathematical formulae and equations that fall into the ‘Advanced Mathematics’ camp, rather than modelling natural variation, so the opportunity to dabble in stats never arises.  Instead, mathematical knowledge feeds into computer programming to run loops, calculus, algebraic equations, and a whole number of other mysterious things.

When you create statistical models, yes there is still an element of programming to it.  But the underlying logic is quite different.  Statistics may fall under the umbrella of mathematics, but they have quite different applications.  For example, if I was to write a program that would could calculate different acoustic measurements from a bunch of recordings, this would be quite different to writing some code to compare those resulting measurements.  A fine line, but a line nonetheless.

Each year, I help teach a course on Quantitative Biology – which is basically statistics in disguise.  I help guide undergraduate biology students through their first steps in statistics and introduce them to a simple software program which will do most of the basic stuff for them in a couple of clicks.  Each year there are a few students who complain that they’re no good at maths, that they’ll never understand this, that they don’t see the point.  Yet by the end of term they’re analysing and clicking away without hesitation, and (in the words of one student) “finally understanding the results sections of papers”.  The key is removing the fear of statistics instigated originally by a fear of maths.

“Put your money where your mouth is”

Over the past few months, I have been working towards completing my first PhD paper.  This has focused on describing the soundscape of a section of the Swan River, and among other things involved modelling the occurrence of different sound sources across different temporal scales.  As a result, after a long sabbatical whilst in pursuit of fieldwork skills / scholarships / rent money, I was thrown in the deep-end of statistics.

p-valueAt first I avoided it; there were plenty of other things to do, and to be honest the thought terrified me.  After all, I failed this at school!  My Undergraduate and Masters classes were okay, but not particularly pleasant!  Can’t I just pay someone to do this?!  But, after completing every other possible task, I took a deep breath, opened our collection of Alain Zuur books, and plunged back in.

And whilst I wouldn’t say that I loved it, there was some enjoyment.  I liked investigating my data, confirming relationships, and finding significant results.  There were a few temper tantrums, but hell did I learn a lot.  So for now, I’d say that statistics and I have a cautiously optimistic relationship.

Conclusion

Hey girlSo in summary, mathematics is classroom theory whilst statistics is real-world applied data.  To be good at statistics, you don’t actually have to be particularly good at maths.  What you do need to be good at is problem-solving, applying logic, manipulating information, and pulling biological meaning from numbers.

In fact, I would even go so far as to say there is a significant difference between mathematics and statistics!

[Note – In statistics circles, this joke is hilarious.  Admittedly in normal circles, it may fall somewhat flat.  Hopefully my undergrads get it…]

And if nothing else, at least studying statistics has opened up a whole new world of internet memes!

Heteroscedacity

Intro to Underwater Acoustics: Two dolphins walk into a bar…

One of the things many scientists find challenging is how to explain their research in an interesting manner.

It’s one thing preparing your research for academic publications – there is a recognised structure to follow, certain items to always include, and feedback from co-authors and reviewers to improve your writing.  But presenting that same information to the general public is a whole other ball game.  How do you keep a class of undergraduates interested for a whole 2hr lecture on underwater acoustics?  How do you encourage community volunteers to develop scientific thinking skills?  How do you explain your research to media personnel in a way that makes it exciting and worth sharing?

These are problems that I find really interesting.  Obviously traditional science communication (academic publications and presenting at scientific conferences) is important.  But I’ve spoken before of the importance of also becoming a virtual scientist, and learning new science communication techniques to promote your research.  So I was pretty chuffed last week to find myself at a day-long workshop on “Science Communication and Presentation Skills” as part of FameLab Australia.

Bringing Science into the Spotlight

Taking the Stage at FameLab Australia WA Competition

Taking the Stage at FameLab Australia WA Competition to discuss underwater acoustics

FameLab is one of the world’s leading science communication competitions.  It aims to get people “talking science” by mentoring young scientists and engineers to turn them into awesome communicators.  Similar to the 3-Minute-Thesis Competition (3MT), speakers are given only 3mins to explain their area of research – no powerpoint, no labcoats, no jargon!  Organised by the British Council, there are over 45 countries participating in the event, having their own national finals to determine their competitors for the final FameLab International Competition in the UK.

I was encouraged by Curtin University to enter, so went along last Thursday to the workshop, which culminated in the WA State Finals that evening.  The workshop was held by three local science communicators – Emma Donnelly (Science Outreach Coordinator; Curtin University), Sarah Lau (Communication Managed; ChemCentre), and Renae Sayers (Theatre and Events Coordinator; Scitech).  We spent an amazing day bouncing around between flaming hands, personal brands, communication platforms, and vocal toolboxes.  It was like a step back into my former Science Presenter life…  If I could find a way to incorporate explosions, liquid nitrogen, and / or flaming limbs into my dolphin presentations, I would be complete!

Like Taking a Keyboard from a Baby

For my talk, I really wanted to get people thinking about underwater soundscapes.  To do this, I wanted to use an example that people could relate to – and since I knew my audience would majorly consist of young to middle-aged adults, I figured comparing the underwater environment to a bar would be a pretty nifty metaphor! Almost everyone in the audience had probably experienced the masking effects of background noise in a pub at some point, so it nicely familiarised the problem faced by dolphins.

How do a keyboard and a martini glass explain underwater noise?

How do a keyboard and a martini glass explain underwater noise?

But how to illustrate this on stage?  FameLab requires the use of a prop, which I struggled with for a while.  I got a friend to record some bar sounds from his weekend exploits, but playing them on stage quickly became a logistical pain.  The rules didn’t allow me to use the FameLab sound system, and bringing my own wasn’t feasible.

But a brainwave on the treadmill (I often problem-solve whilst walking) reminded me of the last time I was babysitting.  Owen wandered over to the electric keyboard, switched it on, and pressed the ‘random filler’ option to churn out some beats before dancing around in circles for ten minutes.

Random cheesy filler music would make a great bar-sounds alternative – loud enough to make the point, whilst being tacky enough to be funny.  Win!

Two Dolphins Walk into a Bar…

The resultant talk wasn’t filmed as part of FameLab, but Phil managed to catch the talk on his phone.  The volume is a bit low, but still gives a pretty good video of my performance!

"Tursiops Wins Again!" - Lyn Beazley presents me as the FameLab WA People's Choice winner

“Tursiops Wins Again!” – Lyn Beazley presents me as the FameLab WA People’s Choice winner

I was delighted to be awarded People’s Choice by audience vote, but unfortunately I didn’t make it through to the Australian Finals.  The judges consoled me afterwards by saying that it was my lack of results rather than my performance which hindered my progression to the next round, and strongly encouraged me to come back next year.  Although, as a friend kindly pointed out, it means I got the votes of 200 audience members as opposed to 3 judges!

Regardless, I still enjoyed the whole experience!  I always enjoy the chance to talk about dolphins and get people excited in science!  And it was a wonderful opportunity to meet some fellow science enthusiasts whilst flexing my science communication skills.  Plus applause isn’t something you get often in research, so that was pretty appreciated!

A massive congrats go to Amber Beavis (WA Museum) and David Gozzard (UWA) who were the winner and runner-up for the WA competition.  I can’t wait to see you guys at the Australian final down at Fremantle in May!

Any More Talks?

But looking at the birthday card I got from the department this week, perhaps I should be focusing more on my research for a while – I appear to be getting a bit of a reputation 😛

Sarah's Birthday Card 2015

What a Fluke – Citizen Scientists Sight Whale Species First for Europe

Last week, two friends enjoying a beach-walk in the Isles of Scilly saw an unusual-looking whale not far off the shore.  They quickly used their mobile phone to take some photos, and noted down the relevant sighting details.  This information was later submitted to the Sea Watch Foundation, a UK marine environmental research charity.  As the whale did not appear to have a dorsal fin, the ladies assumed it was a sperm whale – which would have been unusual in itself, given that this species is a deep-water specialist.

The Mystery Whale

When the cetacean experts at the Sea Watch Foundation reviewed the photos, they were astonished to realise that what the ladies had sighted was even more unusual!

Dr Peter Evans, Founder and Director of Sea Watch Foundation, admits that the photos were a challenge.  “Even with enlarging them, and trying to sharpen them up within Adobe Photoshop, it was very hard to pick out the more subtle features due to the low resolution of the pictures, or even to tell exactly what part of the body was showing in some of the photos“, he says.  “One image, however, showed the animal closer than the rest, and revealed the shape of the head and even the jaw-line“.

The head of the whale, photographed by Fay Page / Sea Watch Foundation

The head of the unusual whale sighted in the Isles of Scilly last week.  Photo: Fay Page / Sea Watch Foundation

This curving jaw-line eliminated sperm whale as an option, as this toothed species has a very straight mandible as opposed to baleen whale species who show a downwards-curving jaw.  Dr Evans sought second-opinions from colleagues in the US, including experts such as Dr Tom Jefferson from Texas A&M University, Dr Phil Clapham from the government agency NOAA in Washington DC, and Dr Scott Kraus from New England Whale Museum in Provincetown. They isolated identifying features, including the curved jaw-line, the lack of a dorsal fin, a light patch under the chin and some black spotting along the top of the head.

And the Answer is…

The consensus agreement was as exciting as it was unexpected – a bowhead whale.  Given the context of a photo showing one of the ladies entering the water with the whale, this animal is thought to be a juvenile.  Adults can grow up to 20 metres long and weigh almost 90 tonnes.  Bowheads appear to be one of the longest-lived whale species around, with some animals thought to be 200 years old, based on old Inuit harpoon heads recovered from hunted individuals.

Anna Cawthray wades into the water to get a closer view of the animal, which shows little reaction to her presence. Photo: Fay Page / Sea Watch Foundation

Anna Cawthray wades into the water to get a closer view of the animal, which shows little reaction to her presence. Photo: Fay Page / Sea Watch Foundation

A First for Europe – But Why Now?

Excitingly, this is the first sighting of a bowhead whale in not just the UK, but the rest of Europe.  These whales normally live in the high Arctic, where they suffered severe exploitation by commercial whales since the 1500s.  By the 1920s, there was thought to be only around 3,000 individuals left.  However, thanks to the cessation of commercial whaling in 1986, their numbers appear to have increased to around 15,000 – 20,000 animals, mainly in the Beaufort Sea and Arctic Ocean.

But the question now is, what was a bowhead whale doing so far south?  There have been increased sightings of warmer-water species around the UK over the past decade, presumably as a result of global warming encouraging species to extend their ranges north-wards.  So to find a cold-water specialist so far south is enigmatic, particularly as bowheads generally tend to never stray far from the ice-edge.  Dr Peter Evans suggests that global warming could still be to blame.

In March 2012, a bowhead whale was photographed in Cape Cod Bay, New England, and the same individual re-appeared in the same area a year later, in early April“, he explains.  “These records far from the natural range of the species may in fact be the result of ice fragmentation, leading to animals straying further south. The welcome increase in the size of the West Greenland population may also be a contributory factor for why this creature appeared some two thousand miles from its normal range.

The Value of Citizen Science

From my point of view, one of the other important realisations from this sighting is the role citizen science has to play in research.  It is obviously impossible for researchers to be everywhere at once – to be honest, the further you progress into a marine research career, the more time you spend land-locked at your desk!  So having trained eyes, in the form of citizen scientists, scattered around the coast provides whole new opportunities for data collection.  Citizen science also promotes awareness of the natural world, by educating volunteers, connecting them with scientists, and actively engaging them in conservation.

The Sea Watch Foundation was founded in 1991 to find out more about cetaceans in British and Irish waters.  It aimed to do this by involving the public in the study of these animals, rather than relying on occasional scientist-led surveys and examination of dead animals from strandings.  Sea Watch Foundation now has two main offices in the UK, as well as 35 local groups of observers who have generated thousands of sightings.

Why not explore what citizen science projects operate near you?

 

 

Is it a plane? A duck? A police car? No, it’s a fish…

For the last few weeks I have been working on the first chapter of my PhD describing the underwater soundscape of the Swan River.  Overall, this has been a really good way of becoming more familiar with identifying underwater sounds.  By far the most baffling of which have come from fish.

Hard-core headphones are becoming my default fashion accessory at the moment...

All about that bass: Hard-core headphones are becoming my default fashion accessory at the moment…

It turns out that many fish species produce a whole variety of ridiculous sounds, including quacks, knocks, grunts, sirens, trumpets and even Rolf Harris impersonations (sounds like his infamous wobble-board).  These sounds are all produced in different ways:  some are made using sonic muscles located on or near the swim bladder; others sounds are the result of the fish rubbing together or striking its skeletal components; and sometimes even changes in swim speed or direction can result in noise production.

But, like many animal sounds, the purpose of many fish noises is still to be determined.  Sound production might be intentional, in the form of vocalisations or calls, in which case noises are most likely signals to other animals (e.g. to attract mates, warn off competitors, co-ordinate with conspecifics, or raise the alarm about predators).  However, sounds can also be produced unintentionally as the result of feeding or swimming.  And when your subjects are mostly occurring in the cold, dark oceanic depths it can be pretty tricky to figure out the behavioural context of recorded sounds!

The majority of sounds produced by fishes are of low frequency, typically less than 1000 Hz.  By themselves they can be pretty hard to pull out of a large dataset, thus requiring a systematic search through potentially months of data.  But a really cool characteristic of some fishes is that they call in choruses.  This is when multiple (dozens or even hundreds) of individual fish within the same area produce the same call.

These choruses occur all over the Australian continental shelf, in both tropical and temperate waters and were first discovered in the late 1960s.  Many show significant seasonal trends in chorus levels and differences between years, potentially indicating that chorus activity reflects secondary productivity (see “Continental shelf fish choruses in Australian Waters” by Robert McCauley and Douglas Cato).  Others are reliably produced at specific times of year, and are believed to be associated with reproduction (see “Fish choruses from the Kimberley, seasonal and lunar links as determined by long term sea noise monitoring” by Robert McCauley), although the nature and intensity of some reproductive choruses can change in association with physical and environmental cues (see “An investigation into active and passive acoustic techniques to study aggregating fish species” by Miles Parsons).  Thus, these calls can play significant roles in the life function of many species.

Great to know that, in all these long hours you spend sitting at the computer, you are probably listening to fish sex!

Studying Snubfins in the Kimberleys

Have you ever heard of a snubfin dolphin?  Not many people have – and up until 2005, no one had at all.

Snubfin dolphins in Roebuck Bay (Photo Credit:  Sarah Marley)

Snubfin dolphins in Roebuck Bay (Photo Credit: Sarah Marley)

In that year, what was previously considered to be a bunch of Irrawaddy dolphins swimming around off the northern coast of Australia, was discovered to actually be a separate species entirely.  And so snubfin dolphins became Australia’s first endemic species of cetacean.  But now, almost ten years later, we still don’t know a whole lot about them.

As part of the Kimberley Marine Research Program, the Western Australian Marine Science Institution (WAMSI) is funding research into the distribution, abundance and genetic connectivity of Australian snubfin and humpback dolphins across the Kimberleys.  This is a collaborative research project, involving scientists from Murdoch University, Curtin University and Australian National University.  Through a mixture of visual observations from vessel-based surveys and acoustic monitoring using underwater noise loggers, the project hopes to improve our knowledge of where and when dolphins occur.  It will also investigate the effectiveness of using noise loggers as an alternative technology for collecting data on distribution and seasonality of dolphins across the Kimberleys.

Listening for snubfin dolphins in Roebuck Bay

Listening for snubfin dolphins

During July and August this year, I was fortunate enough to be involved in the Roebuck Bay component of this project.  My supervisor Chandra and I spent a few weeks working with Dr Deb Thiele (Australia National University) to collect visual and acoustic data on the snubfin dolphins of Roebuck Bay.  It was a real pleasure to work with Deb, who has been conducting research in Roebuck Bay for several years on the abundance, habitat-use and behaviour of this snubfin dolphin population.  We were also working in with local Yawuru Indigenous Rangers Cornell and Johani, who helped us on the boat to collect observational and photographic information on the dolphins.  And to finish off our Snub-Team, we had Jason from Environs Kimberley who helped us navigate through the bay.  The Kimberleys are a stunning place in general, but it was especially great to explore it with people who know the area (and its wildlife) so well!

Over five weeks, we spent a lot of time out on the water and became familiar with a whole host of Roebuck Bay’s other marine residents.  Sightings of dugong, turtles, manta rays, sharks, sea birds, and various fish made every day unpredictable but very special!

Chandra, me and Deb

Chandra, me and Deb.

I’ve been remarkably quiet the last wee while partly because I’ve been away on fieldwork.  But also because it involved such amazing animals, cool people, and beautiful surroundings that I had no idea how to begin describing it!  A large part of PhD life revolves around stress – the pressure of making progress, meeting deadlines, producing outcomes.  But an important part of PhD life is to realise how lucky I am to have these experiences, travel to these places, and meet these people.  And this trip was definitely one of those fortunate events.

The (After) Life of a Whale

Over the last few weeks, a small town in Canada has lived in fear of exploding whales.

Seriously.

A Whale of an Explosion

At the end of April, a dead blue whale washed up on the shore of Trout River, Newfoundland.  Amid concerns it could be a shipping hazard if dragged out to see, locals were forced to leave the whale decomposing on the beach whilst local and federal authorities argued over who should deal with the remains.

Inside a blue whaleThe carcass then proceeded to expand to about twice its normal size due to bloating from methane gas, a normal by-product of decomposition.  Unfortunately, there is only so far a bloated blue whale can stretch, leaving local residents on stand-by for a pretty big bang.  Strange as it sounds this is a legitimate concern – last year a washed up sperm whale in the Faroe Islands exploded as a biologist attempted to dissect it (warning:  video not for the faint-hearted).

Eventually, a team from the Royal Ontario Museum headed over to dismantle and remove the blue whale – a feat which took them almost a week.

A Sight to See (and Smell…)

Whale carcasses aren’t that great in general, regardless of their explosive potential.  A few years ago in Scotland, I took my sister to see a washed up sperm whale at our local beach.  We arrived at the car park and started walking.  When we were 1km away, she sniffed a few times and asked “What’s that smell?”.  It only got worse.

Dead sperm whale - winner of Aberdeen's Top Tourism Attraction 2009.

Dead sperm whale – winner of Aberdeen’s Top Tourism Attraction 2009.

But despite this, hundreds of people came to see it.  The carpark was overflowing for days whilst people made the trek to see the spectacle because, dead or alive, it’s just not every day you see a sperm whale.  People brought their kids (who poked it), dogs (who rolled in it), and cameras to remember the experience.

So, given the high number of marine mammals out there, why aren’t we constantly assaulted by the stink of washed-up whales?  When they’re not washing up on our beaches and becoming a gruesome attraction, what happens to the remains of whales and other marine life?  The answer:  Whale Fall.

Whale Fall

Deep-sea zones are pretty special when it comes to food-chains.  A lack of light means no plant life, which is generally the foundation of most food webs.  Instead, the deep sea ecosystem consists mostly of scavengers, who are fed from above by a constant drizzle of organic particles and detritus known as ‘marine snow’.

But every so often, a really big particle falls in the form of a whale.  And when this happens, the whole community turns up for a feast.

Recently, a deep-sea graveyard was discovered off the coast of Angola by remotely-operated vehicles (ROVs) conducting oil and gas exploration.  Consisting of a dead whale shark and four rays, this represented a surprisingly high concentration of deceased megafauna over a relativley small area.  Scientists are now using this footage to compare the species composition of scavengers on the shark and ray carcasses to the scavenger species present on whale falls.

Ecosystems within ecosystems.  A pretty cool example of how life goes on!

Fieldwork Update: Watch out dolphins, Big Sister is watching (and listening!)

Over the last couple of months I have had a busy whirlwind of deploying noise loggers; learning how to program recording schedules and then process acoustic data; complete health and safety forms; obtain permits for area use; train volunteers for visual surveys; organise fieldwork shifts…  and this is before the fieldwork has even started!  But now it’s all underway and the data is coming in!

Eavesdropping on Dolphins…

Sylvia and Mal from CMST head out into the Swan River to help deploy my first batch of noise loggers

Sylvia and Mal (CMST) head out into the Swan River to help deploy loggers

Back in November 2013, three noise loggers were deployed in the Swan River as part of my PhD project examining the acoustical and behavioural response of coastal dolphins to noisy environments.   I have been lucky enough to have great support from the students and staff at CMST to help me with deployments.  Now the first batch of acoustic data from this first logger deployment is in my office, ready for processing!

These noise loggers record underwater sound produced by ambient (wind, waves), biological (dolphins, fish, crustaceans), and human sources (vessels, traffic, and construction).  For more info on these noise loggers, see my previous post on recording whale sounds in Albany.  Whilst I am examining this first acoustic data batch, the noise loggers have been moved to new locations and are busy recording more underwater sounds.

Over the next year, I will be deploying noise loggers at several spots throughout the river.  I can then use these data to describe the underwater soundscape of the Swan River and examine the vocal behaviour of bottlenose dolphins.

…  Whilst Watching from Above!

Visual observations of dolphin behaviour began in January 2014.  I am conducting visual surveys at various vantage points along the shoreline, using a theodolite to record dolphin movements and behaviours in the river.  This visual information can then be used to understand the context of dolphin sounds and their use of the underwater acoustic environment.

A theodolite is traditionally a surveying instrument, used to create 3D models of the landscape.  It does this by selecting different points, then measuring the horizontal and vertical angles to give an exact bearing and distance to each point; this creates a scale map of the area.  But we can also use this technique to get the position of objects out at sea – such as dolphins!  So we can use a theodolite to map a dolphin’s position each time it surfaces, giving a very fine-scale track of how the animals are using an area.  The added bonus being that the dolphins are not aware of our presence, so we do not have to worry about disturbing the animals and influencing their behaviour.  Although I do often wonder if they have a “feeling of being watched”…

Volunteers Elly and Bec join me surveying for dolphins in the Swan River

Volunteers Elly and Bec join me (and theo) surveying for dolphins in the Swan River

To run these visual surveys, I require a theodolite team:  one person entering data on the computer, one collecting positions using the theodolite, and some others to find the dolphins!  Thankfully, I have had an overwhelming amount of support from my ex-students (and some marine biologist friends), and currently have around 25 volunteers donating their time to help out in the field.  Many are studying or working full-time, making their contributions all the more amazing and appreciated!

But we have had some particularly awesome dolphin sightings to make it all worthwhile – and even on quiet days, the great team spirit (and masses of life stories to tell) keeps us pretty entertained!