Here we are, Neptune!

We have officially become shellbacks! In other words, we have crossed the equator by boat. Tonight we stopped at the equator to throw coins over (an offering to King Neptune!) and have dinner. For most of the scientists (all but 3) this is their first time crossing the equator, and we are all excited!
We had a plume station this morning and this evening we will be doing another station closer to the edge of the plume. We are seeing some pretty interesting things!

More updates to come. All hail king Neptune!!!

Another ANACONDAS blog

Mo, our colleague aboard the Atlantis also has a blog
http://dornsife.usc.edu/plume-research/

Andrew

At Mouth of Amazon River

River water as far as the eye can see.

We made it to the mouth of the river!  The water's brown, fresh and extremely shallow, yet we still can't even see land. The water's the color of coffee, and about as fresh.  Fishing boats are everywhere, so we know there's plenty of life in the water.

In most rivers, the salinity gradually drops within the estuary, inland from the ocean.  Due to the volume of freshwater flowing from the Amazon, the salinity in the remains near zero all the way out to the sea.  As this is the first time this project has come this close to the river, we're all excited for our sampling today.  Is this a riverine community?  How does the sediment differ here compared to the high salinity locations?  Is there any photosynthesis in this murky water?  Am I working as an oceanographer or limnologist?  Today, we'll find out all of this and more.

We've just arrived on station, so it's time for me to get to work.  So long!

Andrew

Greetings people of the land! We're here in Brazilian waters, right up in the excitement of the Amazon River Plume. We have observed many interesting creatures and there seems to never be a dull moment on the ship. The schedule changes by the hour and we grab sleep when we can. 


This is a picture of some stuff that was pulled up in the MOCNESS from the fresher surface waters in the plume. 

This is a mass of pteropods that calcify tiny little shells to swim around in. Pterapods are sea snails that flap their appendages in a way that has earned them a name "sea butterflies". Here what we see is just their shell and the dark bluish green spot that is the phytoplankton they've ingested. Here's a sweet video of some pteropod flapping action with other species. Our zooplankton specialist on this expedition, Dr. Debbie Steinberg, remarked she had never seen this organism assembled in such abundance before. 
Photo: Jason Landrum

Photo: Jason Landrum

Next we have a creature of the deep that was caught in the deployment of the sediment sampler. This is either a viperfish or a gulper eel. We are lacking an icthyologist on this cruise, but sometimes we are allowed to simply enjoy the beauty of marine life instead of studying it. 




Check out those jaws!!! 

Photo: Jason Landrum

Photo: Jason Landrum

What impressive geometry and colors. 


Last we have a little specimen that was found caught in sewage systems. This is a larval form of the river eels that are commonly found in sushi as 'unagi'. This lil critter is an example of a fish with a catadromous life cycle. Catadromous species spend most of their lives in fresh water and migrate to the sea to breed. The larvae then develop for a short time in the marine environment and return to river environments. 

Photo: Kristine Okimura

Last here's a photo of the sediments crew waiting for their coring instrument to come up in the impressive Atlantic sunset. 

Photo: Kristine Okimura

Until next time!


-kristine

Good evening from the RV Atlantis! We are at station 5a today, but we didn’t do any CTD Casts today because we got into the station pretty late. Instead we had a science meeting and worked on our projects! Andrew spent a lot of the day in his rad van processing his samples and finishing incubations. I just finished my second nutrient addition experiment today, which basically involved a ton of filtering! This batch was mostly coastal diatoms and was a plume station- the salinity was about 17! The first batch was a blue water/edge station with mostly trichodesmium. It will be interesting to see if the nutrient additions (I am using a control, ammonium, nitrate, and phosphate) have any effect on chlorophyll A concentration or on phytoplankton community composition!

 As of today we are officially in Brazilian Coastal Waters, and we have been going in and out of the amazon river plume with the salinity fluctuating between 36 ("blue water" or water outside of the bloom), and down to 17 for some of the plume stations. Yesterday at station 4, we had a very "green" station with low salinity and an abundance of coastal diatoms such as Calcinodiscus, pseudo Nitzchia, Skeletonema, Chaetocerous, Guinardia, Melosira, Rhizosolenia, and of course Tricho! These are just the genus names- Andrew could tell you the many different species!

We've also been getting to look at some amazing deep sea creature thanks to Debbie Steinberg's zoology group. We've seen a lot larval crabs, fish, and other marine organisms. We saw some beautiful bright red deep ocean shrimp (since red light does not reach the deep ocean, they appear black to predators). We also got to see various black fish with spots called photophores on their bodies which can change colors. This evening we got to see a pretty amazing tow that Kristine will tell you about!

It is very hot and humid during the day, but cools down a bit at night. As the ship moves at night we can see the bioluminescent organisms glowing in the water. Pretty awesome! More soon! And I promise pictures, but I can't seem to find my camera. Fortunately there are only so many places it can be...

-Rachel

Working at Sea

It's been a long day of sampling and experiments, so here's some pictures of the work done on research vessels.

Kristine helping to deploy the CTD rosette, so we can collect water samples.  

Rachel sampling for Synechococcus, a small unicellular algae.

I'm sampling Trichodesmium, a colonial nitrogen fixing algae.

Nick cleaning a coring tube, used to collect sediment samples from the seafloor.

Tish, our chief scientist, collecting seawater samples for chemical analysis.

Brandon sampling zooplankton collected in the MOCNESS.

Station 1!

Today was our first day of sampling! Kristine woke up at midnight, 1 O’clock, and 2’Oclock in the morning to take samples of nutrient concentrations, phytoplankton for identification, photosynthetic pigment analysis, and measurements of organic nitrogen and carbon levels. These were taken for our underway sampling (when we are steaming from station to station). Andrew got up before sunries to take a net sample and see what phytoplankton were in the water. Today’s station was near the edge of the Amazon River plume with a salinity of about 31. Andrew found mostly Trichodesmium, with a few diatom-diazatroph associations. There was also some sargassum in the water.

Some of our fellow scientists took sediment core samples early in the morning to look at natural isotopes, after which there were 3 casts of the CTD Rossette to sample for many different parameters. Various labs examine pCO₂ levels, marine microbes, nutrients, seawater optics, genetic diversity and gene expression, and all kinds of organisms from marine viruses to zooplankton.  During the third cast of the CTD (at 11am), Andrew took samples to measure the primary productivity and carbon excretion of phytoplankton and Kristine assisted by taking samples for chlorophyll A , DOC (dissolved organic carbon), and phytoplankton identification. Andrew is incubating his samples for 24 hours in one of the awesome incubators on the deck (look forward to pictures from future incubations!), and will be able to find out how cells behaved tomorrow by measuring their uptake of radioactive carbon (¹⁴C) in his “Rad Van”. Rachel took samples to quantify and identify phytoplankton, taking special samples for Trichodesmium  (colonies of nitrogen-fixing cyanobacteria) and very small single-celled cyanobacteria such as Synechococcus and Prochlorococcus.

Later, some labs took samples of zooplankton using the MOCNESS (Multiple Opening/Closing Net and Environmental Sensing System…yes, I had to google that). We were going to try to do another two CTD casts to take deep water samples this afternoon, but weren’t able to because of some CTD communicatioin errors. Because of this we are taking off from this station a little later than expected. Tomorrow we will have a similar schedule to the one we had today, but may see some differences in phytoplankton abundance and distribution since we are moving closer to the plume center.

Life on the boat is great! None of us have gotten seasick yet, and the food is wonderful. The chefs are very thoughtful and put aside plates of food for us when we have to work through a meal, and the crew is very friendly. Kristine and Rachel are sharing a room on the bottom level of the boat, and Andrew is one level up. We will keep you posted on our future sampling and experiments!

-Rachel

En Route!

We've finally received our permits from Brazil, and are aboard the Atlantis on our way to the first station now.  Tomorrow is the first day of sampling and is going to be insane.  We’ll all be running around trying to get our various samples, getting in each other’s way and generally making a mess of things.  It will make a good practice run, and at least a portion of it will provide some good data.

While en route, we’re finalizing our preparations – preparing reagents, labeling bottles and learning to use the onboard gear.  We participated in safety courses and exercises, in preparation for any potential mishaps.  We're collecting our first batch of samples as we travel, pumping water for underway sampling for phytoplankton.

The carpenter lab team is composed of Kristine, who measures DOC and collects the underway samples; Rachel, who is collecting phytoplankton samples and preforming nutrient amendments; and myself - I measure productivity and DOC excretion by algae.

-Andrew