Return to Sea: Seabirds, Seamounts, and Science

By Jessie Bolin (2019 student alumni)

I’m Jessie, a first year PhD student at USC, and I was lucky enough to be a student participant on this year’s CAPSTAN voyage aboard RV Investigator from Hobart to Fremantle. The focus of the program was to train Australia’s next generation of interdisciplinary marine scientists, and we were exposed to field and lab techniques in sedimentology, geophysics, plankton, hydrochemistry, physical oceanography, and fauna identification. This was my first introduction to life at sea aboard a scientific research vessel, and I was hooked.   

Me on the fifth deck of RV Investigator (Photo Credit: Chantelle Ridley)

I have just returned from my second voyage on RV Investigator, where we spent 28 days cruising around the Coral Sea. The primary voyage goal, led by Chief Scientist Associate Professor Jo Whittaker, was to further understand the spatiotemporal extent of mantle plume activity in the Coral Sea, and to investigate how features in the region formed, like the Tasmantid and Lorde Howe seamount chains, and the Louisiade Plateau. This was done by using dredges (think of a massive net with teeth) to gather rock samples from seamounts and ridges, and using the multibeam echosounders to map the seafloor.

The rock dredge, affectionately named ‘Schnappi,’ with a nice haul (Photo Credit Amelia Smethurst).

In addition to the primary project, the voyage had other supplementary projects:

  • Understanding spatial links between geomorphology and biodiversity in the Coral Sea Australian Marine Park
  • Spatial and temporal variability in the distribution and abundance of seabirds
  • Collection of dead invertebrates dredged with geological samples
  • Transit over the likely wreck sites of the USS Lexington and USS Neosho
  • Educator on Board program
3D visualisation of Lexington Seamount (Photo Credit: Jessie Bolin).

I was involved with the “Seabirds at Sea” project, and my role was a seabird and marine mammal observer for Birdlife Australia. A typical day for our team would involve starting observations at Monkey Island (the top level of the ship) just before sunrise, and recording the number, species, and behaviour of any observed seabirds and marine mammals through to sunset, using a standard survey protocol used since the 1980s. At the end of our journey through the Australian, Papuan, Solomon and New Caledonian EEZ’s, we recorded over 14,000 seabirds and 27 species.

(Left) Another day at the office. (Right) An epic sunset. (Photo Credit: Jessie Bolin)

Out of the 27 species, my favourite was the red-footed booby. They’re quite the comical bird, and at one point, we had over 50 red-footed boobies perched on the mast (…and scientific equipment), which broke a record for RV Investigator. Boobies feast on flying fish, and it was beyond exciting watching the boobies chase and catch flying fish that were disturbed by the ship. Flying fish can glide up to 70 km/hr to escape predators, which makes the boobies even more remarkable! Also, I witnessed my first instance of kleptoparasitism by a frigatebird. Instead of catching their own food, frigatebirds incessantly harass other birds – usually boobies – causing the victim to regurgitate their own food, which the frigatebird then steals in mid-air.

(Left) Red-footed Boobies in pursuit of a flying fish. (Right) A Lesser Frigatebird. (Photo Credit: Eric Woehler)

The Investigator is a ship for all scientists, which meant I was exposed to a diversity of perspectives and scientific research from completely different research areas to my own. Each day we’d have a ‘science talk’, where someone volunteered to give a talk about something they’re working on. Talks were diverse, and ranged from intraplate volcanism in Eastern Australia (Ben Mather, USyd), to using AUVs and ROVs to measure the spatial variability of algae under Antarctic sea ice (Vanessa Lucieer, UTAS), to methods of Ancient Egyptian mummy preservation (Quinn Anderson, USyd). Never in my life would I have thought I’d get to learn about Ancient Egyptian mythology on a research ship in the middle of the Coral Sea, yet there I was. We also celebrated international pet rock day, which was a real hit – particularly for the geology team!

(Left) Entrants for International Pet Rock Day competition. (Right) Jamie Menzies, one of the Educators on Board, giving a talk on embodied learning for young scientists. (Photo Credit: Jessie Bolin)

A special moment for me (and many of the other scientists) was our final evening on the ship. The sun was setting, and we had just crossed into the East Australian Current on our way home to Brisbane. Seemingly out of nowhere, multiple pods of 50+ pilot whales and common dolphins appeared, and some of the dolphins started riding the bow waves! I’ll never forget the screams of excitement and complete joy that the marine mammals’ presence brought to the scientists and crew. They stayed with the ship for what felt like ages – it was a perfect end to a truly wonderful voyage.

Waiting for the final rock dredge in the sheltered science area (Photo Credit Jamie Menzies).

For any budding marine scientist, I’d highly recommend going on RV Investigator. My background is in marine ecology and data science, yet going on this voyage meant I got to learn about marine geology and geophysics, and I even discovered a newfound interest for all things basalt and deep-sea volcanism. Being at sea for a month has taught me loads about the value of interdisciplinary marine science and working in a small, tight-knit community, and the experience has forged friendships for life. Thank you to the CSIRO Marine National Facility for a generous grant of sea time that made this voyage possible – I can’t wait to go back!

The science team, support staff, and some of the ship’s crew (Photo Credit Huw Morgan).
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Back on Land!

By Annabel Payne, Macquarie University

We’re back! Well, we’re in Fremantle, Western Australia. The past two weeks have flown by, and it feels strange that now it’s all over and we’ll be heading home to our respective cities. Meeting new friends and learning new skills, I think I can safely say we all had an amazing experience.

CAPSTAN students Kaycee, Bella, and Luke join trainers Lisa, James, and CAPSTAN director April for a photo outside at sunset on the last night on RV Investigator for this year's hands-on marine science training voyage
CAPSTAN students and trainers enjoying a little outside time on our last night at sea (photo credit: April Abbott).

I’ve been to sea before, but this was my first time learning about plankton collection, identifying different climate events from microfossils, counting different birds and mammals, understanding CTD measurements… the list goes on! CAPSTAN has been a brilliant learning experience and if you’re thinking about applying for next year, definitely do!

Monkey Island is the upper most deck on RV Investigator and is dedicated to marine mammal and sea bird observations.  From here, trainers and students can keep an eye out from sunrise to sunset.
Ben and April watch for sea birds and marine mammals from Monkey Island (photo credit: Leah Moore)

I decided to work in the wet/dirty sediment lab because I felt like it might complement the work I’ve been doing at university. I’ve been looking at how changes in sediment provenance influence Neodymium, an isotope usually used to track changes in past ocean circulation. A lot of the age models used are derived from oxygen isotopes in foraminifera. Since we had Stephen onboard, our foram expert from Melbourne, it seemed like the perfect opportunity to learn as much as I could. I now know the importance of a certain species for identifying the last glacial maximum in sediment cores from the Southern Ocean, how changes in size and species distribution are influenced by temperature and light!

The Smith-Mac grab, a box-like tool deployed for sampling the seafloor, is deployed over the starboard side of RV Investigator at sunset during CAPSTAN's 2019 hands-on marine science training voyage.  RV Investigator operates around the clock, meaning deployments can happen day or night.
Smith-mac grab sampler is deployed at sunset

My particular mini project while at sea involved sieving samples from the top and bottom of the cores, separating the different fractions out to see how grain size distribution varied down the canyon we were targeting. In these samples we found a huge variety of forams – some look like popcorn, others look like christmas baubles, and others were perfect spheres. The variety of forms within such a small sample gave me a huge appreciation for just how diverse life is at a microscopic scale.

CAPSTAN student uses a metal spatula to scrap off a thin layer of core along the edge to expose a 'clean' surface.
Prepping the kasten core for sampling by cleaning off the smeared edge

The same could be said for in the plankton lab. The tiny jellyfish, starfish, copepods and various other little critters were fascinating, it was certainly a novel experience being able to see what I’m studying for a change!

A tiny amphipod with a huge black eye floats in the view of the microscope.  This amphipod, along with many other microscopic critters, were caught in plankton nets as part of the 2019 CAPSTAN marine science training voyage.
An amphipod we caught in a net tow as viewed down the microscope (Photo Credit: plankton lab)

From the science to dressing up as sea creatures and trivia, we had a great time. Maddie kept us all singing with showtunes, Sian’s whale calls (which may have something to do with the lack of cetaceans – sorry Sian!), movie nights, through to the excellent food and expert crew. A trip on the RV Investigator is one to remember.

End of voyage group photo with CAPSTAN trainers, students, support team, and some of our crew (Photo Credit: Ben Arthur).

Mud, Mud, Glorious Mud

By Mikala Maher, University of Canberra

After what seemed liked forever, and exceeded excitement on Christmas morning, we finally had sediments to explore. Over the last two days we have deployed a total of four Kasten Corers and two sediment grabs from the shallow shelf to the deep marine environment within a Submarine canyon environment.

A view of the sediment grab sampler being deployed off the starboard winch from a few levels above.  The upper deck is a safe spot for CAPSTAN students to stand without being in the way when they want to see the deployment.
The Smith Mac sediment grab sampler is deployed over the side of RV Investigator to collect surface sediments from 500 m below the ocean surface.

With adrenaline kicking in, samples were prepared and while desperately waiting for samples to dry discussions where held proposing suggestive theories as to what secrets the mud will contain, consulting with the new bathymetry and causing a rave in the observations room.  

Emotions were high with the excitement ongoing deployments and exploring the prepared samples and boy do we have some spectacular organisms and some outstanding structures.

Tag lines are put on the kasten core to assist in recovery from the A-frame on the back deck of RV Investigator during the 2019 CAPSTAN marine science training voyage.
The kasten core is recovered after a successful deployment

My research will be looking at exploring a link to Last Glacial Maximum with shelf sediments. Without further ado, and with credit to the Ice Age, I present to you the sedimentology Mud song.

Mud, glorious mud…we’re anxious to dry it

Two cores a day, our favorite deployment!

Just picture a Turbidite, matching the Bouma sequence

Oh, mud, wonderful mud, marvelous mud, glorious mud.

Mud, glorious mud,

Slide smears and wet sieves

Mud made from plankton

Or hemipelagic rain.

Do nothing but sample,

On mud, magical mud, wonderful mud, marvelous,

MMUUDD

Mud, glorious mud

Freshly plucked from the sea floor

A little smelly but filled with beauties

Soon, we’ll hit the jackpot

Just thinking of gravity cores

Puts us in a mood for

Mud, glorious mud, marvelous mud, fabulous mud,

Beautiful mud,

Magical mud,

GLORIOUS MUD.

Once secured to saw horses in the wet-dirty lab, one side of the kasten core is removed to reveal the glorious mud inside.  Once open, scientists 'clean' the core and then describe it before proceeding to take discrete samples.
Beautiful mud, Magical mud, Glorious mud!

The Art of Science

By Jess Radford, Deakin University

A very important part of research as a scientist is being able to communicate what you have worked on to a wider audience. The general public have varied knowledge and levels of understanding of science so the simpler, clearer, and more engaging the message, the better. The message can be communicated through blogs, documentaries, podcasts, even art. There has always been an ‘us versus them’ mentality between the arts and the sciences. But at the best of times they come together for a common purpose. From the beautiful natural history illustrations of animal specimens, to Attenborough’s documentaries enthralling young and old with sublime cinematography, it’s all a unification of the two disciplines.

Cartoon of 'Sampling the Abyss' that hangs on the wall of the lounge on RV Investigator.  In the picture, RV Investigator can be seen at the surface and a submersible with 4 people is down below amongst angler fish, octopi, and other creatures of the deep.
Fantastic art work in the lounge of the RV Investigator that I love to look at!

I am learning so much during my CAPSTAN voyage, about so much fantastic science from entirely different disciplines that I had no prior knowledge of. Something that took me by surprise was the use of a fascinating piece of oceanography equipment to create miniature works of art. The CTD (Conductivity, Temperature, Depth) is a carousel that holds 36 bottles and is lowered to the oceans depths. On the way back up to the surface, bottles are closed at particular points to obtain samples from different depths of the ocean. While all of this fantastic ocean water sampling is happening, a mesh bag of polystyrene cups that have been decorated are accompanying the CTD down into the oceans depths and back up again. The magic trick is that the polystyrene cups, that are for the most-part made of air, experience the extreme pressure of the oceans depths and the air is squeezed right out of them. What a fantastic way to demonstrate the immense pressure of the oceans depths than with little pieces of art.

CAPSTAN student Jess wears her hardhat as she stands next to the CTD rosette.  The rosette is taller than Jess, with the top of the niskin bottles lining its edge about even with her head.  The sensors (CTD itself) are at the lower part of the cage.
Myself next to the CTD rosette for scale. The CTD can withstand extreme depths, it all depends on the length of the wire available to lower it. The lowest we took the CTD on the CAPSTAN voyage was 4.5 km (into an underwater canyon!)

The “D” in CTD stands for “Depth” but is more of a representation of hydrostatic pressure, the pressure of the water above (and around). So the deeper into the water, the greater the increase of pressure. The CTD and the polystyrene cups can withstand a lot more pressure than we possibly could, which is evident in the air that is lost from the cups at such great depths and amounts of pressure. I decorated three cups; drawing the phytoplankton that would be sampled in the CTD bottles, the CTD itself, and my personal experiences on RV Investigator.

Phytoplankton are plant and algae that occur in a variety of beautiful shapes ranging in size from a few mm to the very tiniest most microscopic. Phytoplankton is extremely important in our oceans as it is the very first link in the food web, providing food for many animals. They are also an important part of the carbon cycle, storing carbon and producing around 70% of the worlds oxygen. So as you might imagine, measuring and collecting quantities and types of phytoplankton in our oceans is very important in monitoring ecosystem health locally and globally.

My three little artworks: phytoplankton, the CTD, and a view of the foremast that I see from the bird and mammal observation deck every day. All next to a full-sized polystyrene cup for scale.

Phytoplankton appears again on my CTD cup. For that cup I drew the CTD carousel that holds the sampling bottles, and drew the sampling bottles representing the different measurements taken by the CTD; oxygen, conductivity (salinity), temperature, current velocities, nitrate, fluorescence (light), and pressure/depth. Generally people aren’t going to know what all of these things are, so my illustrations attempt to convey these in a more approachable way. For example conductivity/salinity is represented as a salt shaker. Even with my science background, I don’t fully understand the ins and outs of all of the measurements and hydrochemistry involved with the CTD, but I hope I’ve presented it in a way that bridges the gap for most people. It’s not so easy to draw on a polystyrene cup, so these aren’t absolute masterpieces, but I hope they’re a good form of communicating some of the science from onboard RV Investigator!

Take me down to Plankton City, where the algae is green and the copepods are pretty

By Sophie Dolling, The University of Adelaide

Where is Plankton City you ask? In the mixed layer; the top most layer of the ocean surface where the water column is largely uniform. How do I know where the mixed layer is? An amazing instrument called a CTD.

The CTD (conductivity, temperature, depth) rosette is deployed from the starboard side of the RV Investigator as part of at sea marine science training on the 2019 CAPSTAN voyage
The CTD in action: lowering into the water column to bring us back the goods

The CTD is loaded with bottles that fill up with water at certain depths in the water column. Each bottle will fill at an individually nominated depth, allowing us to see water from all levels of the ocean. We get to sample the deep Antarctic water, the old oxygen depleted water and the nutrient rich mixed layer water all during one deployment!

A small orange colored sea star from the sieved bongo net samples is viewed through a microscope on board RV Investigator as part of the hands on training for marine science students on the 2019 CAPSTAN voyage
Small sea star found in the larger fraction of the sieved sample

Whilst sampling at the Bonney upwelling zone we were given the task of (hopefully) finding some plankton to identify, sort into size classes, and indicate biomass abundance. To do this, we used a bongo net to collect plankton from different points in the water column. These points were predetermined by analysing data from the CTD. We decided to always sample at 100m deep and one other depth depending on what we saw on the CTD profiles. We were looking for the point where the water column exhibits a sharp change in temperature and density; this is known as the mixed layer depth (bottom of the mixed layer). In basic terms, the water column goes from being mixed to more stratified the deeper you go. The mixed layer depth causes a barrier-type density difference, trapping nutrients above or below the boundary. If nutrients are brought into the mixed layer because of upwelling, the water above the mixed layer depth should be Plankton City; full of yummy nutrients allowing plankton growth.

Voyage participants watch as the two half meter diameter bongo nets are deployed over the starboard side of RV Investigator to collect plankton as part of the hands on marine science training of the 2019 CAPSTAN voyage
The bongo nets on their way down while the team anxiously waited, hoping for plankton to analyse

The Bonney upwelling zone is theoretically a ‘hotspot’ for plankton growth because of the nutrient rich bottom water moving up the water column to the surface through a range of mechanical processes. As we soon figured out, science and the ocean don’t care how far you’ve come to see them; they just do their own thing. The upwelling was not happening, in fact there was most likely downwelling occurring while we were on site. The expected abundance of plankton was largely unknown. What would we see? Would we see anything? Would we see lots?

A small bioluminescent organism is visible in one of the bongo net samples collected by CAPSTAN students on board RV Investigator as part of their hands on marine science training
Sparkly Boy, winner of Plankton Cities Most Beautiful

The bongo net tows did not disappoint. Whilst we do not have the final results of biomass abundance or size class just yet, we do know that Plankton City is an exciting and diverse place. Each of the tow samples were passed through a sieve, separating the plankton into size classes: larger than 100 microns and smaller than 100 microns. Among the inhabitants of Plankton City were a couple of tiny juvenile squids, hundreds upon hundreds of copepods, the spiky tennis balls of the water column (otherwise known as radiolarians), a squishy sea star, and many more wild and wonderful things*. There were two specimens in particular that were voted ‘Plankton Cities Most Beautiful’; Mr Fabulous and The Sparkly Boy. This pair of bioluminescent pretty boys were the talk of the lab**. Mr Fabulous was voted Most Beautiful for his sparkling eyes; eyes that would make Mrs Fabulous swoon. The Sparkly Boy took this one step further, showing off his sparkles all over his body.

Tiny squid is seen through the microscope on board RV Investigator along with other organisms trapped by the bongo nets during the 2019 CAPSTAN voyage.
A small squid found in the larger fraction of the sieved samples.

While on site we were only able to do a handful of bongo net tows. We were able to see some pretty amazing stuff from such a tiny sample size. Can you imagine what else we could find down there? I don’t know about you, but Plankton City is certainly somewhere I want to visit again.

*No squid, sea stars or sparkly boys were harmed in the making of this blog (we let them go back to Plankton City).

Check out my group’s hydrochemistry & oceanography blog on AGU’s The Field!

If you can read this, thank a plankton!

By Anthony Mott, Charles Darwin University

Sure, the bumper sticker says, “If you can read this, then thank a teacher”.  And that is true, you should probably thank a primary school teacher.

But in the six seconds it took you to read to this point you breathed three times, and microscopic plankton produced around two-thirds of the oxygen you breathed into your lungs. In fact, you have been reliant on plankton for much of your oxygen since you were born. This is not to say that the trees, plants and large intact forests such as the Amazon are unimportant, but marine studies since the 1980’s revealed that the tiny microorganisms that photosynthesise like plants and float around in the ocean are much, much more important than anyone realised. Collectively they contribute more oxygen into the atmosphere than any other living species. Plankton matter much more than your science teachers knew when they were trying to pique your interest.

RV Investigator sits at the wharf in Hobart, Tasmania before departing on the 2019 CAPSTAN voyage providing 18 students from across Australia hands-on training in marine science
RV Investigator sits at the wharf in Hobart before the voyage

This week eighteen postgraduate University students interested in the marine environment boarded CSIRO’s RV Investigator and sailed from Hobart on a slow trip to Fremantle to better understand Australia’s marine estate, which is actually larger than all the land Australia is responsible for. Along the way they have undertaken studies of plankton at various locations and at various depths, guided by another 20 senior scientists and technicians.  They also filled in some poorly defined spots by mapping the ocean floor, collected and examined samples of often ancient mud, gravel and ooze from undersea canyons, and measured different currents from the surface all the way to the ocean floor. But breathing is important, so arguably the plankton studies matter the most.

CAPSTAN student Anthony Mott stands on one of the outside decks of RV Investigator as the ship departs Hobart for 10 days of at-sea marine science training
Enjoying the deck of RV Investigator

Plankton are a broad category of tiny, often microscopic organisms that live mostly by drifting around in the water and include both plants and animals.  Some generate energy by acting like plants, and others devour other plankton. Plankton exist in both fresh and seawater, but marine plankton outnumber the rest simply by sheer number. The plankton that generate the oxygen we rely on are the plant-like plankton which photosynthesise just like plants on land – taking in CO2 and water, and releasing oxygen. They can have very short life cycles and can reproduce really quickly when conditions are right – often producing massive natural blooms in response to a sudden increase in nutrients, such as runoff from land or agricultural areas following a major storm.  Most marine plankton are made up of single cells and their small size means they are highly efficient and are an important mechanism for soaking up CO2 from the atmosphere, so plankton are an important part of the global carbon cycle.

CTD rosette with 36 niskin bottles is recovered from the ocean on board RV Investigator as part of CAPSTAN's hands-on marine science training
The niskin bottles on the CTD rosette can be seen coming out of the water

Once the RV Investigator neared the Victorian coast near Portland it positioned itself at the head of three undersea canyons to investigate their role in channelling coastal soil and sand down onto the undersea continental slope-looking at how they funnel cool, nutrient rich deeper water up from the depths up onto the continental shelf. This concentrated source of nutrients underpins a broad marine food web – with plankton being the first organisms to capitalise on the nutrient supply.  Very fine nets were dropped to capture the plankton populations at different depths.  Water samples were collected at the top, sides and bottom of the canyon systems. Collecting samples at different depths and locations provided important information on which conditions best suit different species, as well as provided some insights as to how widely certain species are distributed.  Nutrient rich waters close to the surface may contain up to a million microscopic plankton in one litre of water, whereas similar locations can yield completely different results with variations in factors such as temperature or nutrients. The Southern Ocean that circles just above Antarctica seems particularly important. And 40-odd marine scientists and students want to know why because any change in the mix and number of plankton may have significant implications for oxygen supply and the changing climate.

Deployment of the bongo nets for plankton sampling from RV Investigator as part of the CAPSTAN hands-on marine science training program.
RV Investigator’s crew and support staff deploy the Bongo nets to recover a vertical tow plankton sample

The southern Australian coast is home to many marine species not found anywhere else in the world. This region also attracts much travelled species like Southern Bluefin Tuna that spawn south of Indonesia and migrate south down the WA coast and across the Great Australian Bight to SA and Victoria; Southern Right Whales come here t0 breed and calve. The area also attracts rare and endangered marine mammals like Sperm, Killer, Blue, Minke, and Humpback Whales. It’s easy to be distracted by the big things, but they are all dependent on a sustainable food web that starts with the microscopic things that are easily overlooked. And that’s why 40-odd scientists braved forecasts of 12 metre swells and unpredictable weather to head into remote oceans to study the little, poorly understood, strange, but often beautiful creatures that make an under-recognised contribution to global oxygen and carbon cycles.

Never will I look at mud the same..

By Aaron Puckeridge, University of New South Wales

NEVER WILL I LOOK AT MUD THE SAME WAY AGAIN! Did you know that by looking at mud you can find tiny fossilised animals, or even understand past climates? Neither did I. On land, mud has a dark colour from decomposed animal and plant matter, and it is the same in the ocean. In the ocean, dead animals will sink down to the seafloor and accumulate, eventually forming mud. As a marine biologist I have never appreciated how interesting mud can be!

CAPSTAN student samples the mud from the end of the kasten core on RV Investigator as part of his at-sea marine science training
I sample the core catcher of the Kasten core on the stern deck of RV Investigator

Over the last two days onboard RV Investigator, we have been sampling a deep-sea trench in the Great Australian Bight. The seafloor here sits undisturbed by overhead currents, allowing dead animals to accumulate over thousands of years and form mud. Sampling this mud, up to 3000 metres below the surface of the ocean is where the amazing technology onboard the RV Investigator comes into play. High-resolution sonar gives us a 3D image of the seafloor, helping us to select a site to study. Then we lower a large tube to the seafloor and into the seabed to collect a vertical tube of mud, with young mud at the top and old mud deeper down. At a glance, this looks like any old mud, but under the microscope it is almost entirely tiny animals called plankton.

microfossils and biological debris down a microscope observed by CAPSTAN students as part of their at-sea marine science training
Microfossils and other biological debris in the sediments under the microscope.

Over the coming days we will be looking at these tiny plankton fossils to understand how the ocean above the deep-sea trench has changed the in past. Fingers crossed we won’t get seasick while looking down the microscope!