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Hi all,
Today is our last day of sampling. We started bright and early again at 6am. It rained a bit, but it was accompanied by a full rainbow arching over the boat. Nice way to start off the morning!
You guys are probably wondering how we collect all of the larval fish I showed you on the last blog post. Well, we deploy a bongo net off the back of the boat and a neuston net off the side. Both nets are brought on board and the samples are washed down into the codends. The contents of the codends are rinsed/poured and put into our sample jars. The samples are brought into the wet lab for a closer look and a potential photo. Some of the larger specimens (e.g., tunas, swordfish) are frozen for genetic analyses.
I set up a GoPro around the boat to show you guys how we sample at each station. Let’s take a look of some of our scientists at work:
Bongo nets and the sunset last night. Neuston net.
Rich is collecting water for the YSI and for the food web study. Nina is reading the water's temperature, salinity, and dissolved oxygen.
Rich, Nina, Jillian, and Jason are retrieving the bongo nets. Everyone's rinsing down the nets, while Michelle is recording the
flowmeter data.
Jillian is pouring her plankton sample out of the codend. Jason and Nina are rinsing the bongo nets.
Nina and Jessica are putting the sample into the jar. Jessica is looking at a larval tuna under the microscope/taking a picture.
Alex and Cori just retrieved the neuston net. Jillian, Alex, Cori, and Travis are sorting the neuston net sample.
Jason and Travis sorting through Sargassum. Jason and Alex looking at our catch!
Dr. Michelle Sluis is the PI on the cruise. She is recording the data for each tow (e.g., start time, location, etc.) in the pictures above.
Hope you enjoyed the pictures!
-Nina
Hi guys!
Last night we cruised towards our southern transect. We arrived at our first station and began sampling at sunrise (6am). We've hit 10 stations so far today! We collected many of our targeted species and more!
On the boat, we use a camera attached to our microscope to help us take pictures of the tiny fish. Here's some of our catch:
Dolphinfish larva.
Swordfish larva.
Billfish larva.
Tuna larva.
Frogfish larva.
Alex found a siphonophore.
Cori, Travis and Jillian on deck and ready for the next tow!
All smiles here!
-Nina
Hello everyone,
My name is Nina Pruzinsky. I’m out in the northern Gulf of Mexico with Texas A&M sampling for fish larvae on the R/V Pelican. We’ll be out here from July 1-5th. The scientists onboard include: Dr. Michelle Sluis (TAMUG), Jessica Lee (TAMUG), Travis Richards (TAMUG), Cori Meinert (TAMUG), Jillian Gilmartin (TAMUG), Alex Southernland (TAMUG), Jason Mostowy (TAMUG), Richard Jones (FAU) and Nina Pruzinsky (NSU).
We left the port at LUMCON at midnight on June 30th and traveled to the first station (Station 48) during the night. We started our sampling around 10am yesterday. We finished nine stations during the day and did two night tows. During the day we are using a neuston net and bongo nets to sample for larval fish. The neuston net tows for 10 minutes at the surface and the bongo nets sample to about 100 m depth. At night, we only tow the neuston net. This way, we can compare the differences between day and night tows at the same station. Additionally, Alex is sampling for gelatinous zooplankton (jellyfish) for genetic analyses, Jillian is Gtowing another plankton net to look at the community structure of zooplankton, and Travis is collecting water samples in order to characterize the food web in the Gulf.
Yesterday we caught tunas, billfish, dolphinfish, flyingfish, eel larvae, remora, frogfish, triggerfish, pufferfish, rough scad, lanternfish (at night) and more! Check out the pictures below! As you can see, all of our fish are extremely small!
Today we started sampling at sunrise around 6am and have completed three stations. We already caught some tuna and dolphinfish larvae!
Stay tuned for more pictures and updates on the cruise!
R/V Pelican before depature.
Larval dolphinfish (mahi-mahi).
Tuna larvae.
Triggerfish larvae.
Michelle and Cori preparing the neuston net.
Jillian setting up the plankton net along with the bongo nets.
We also were able to dip net a juvenile tuna last night for my thesis!
Cheers!
Nina
Another day at sea – one of our last for this cruise.
My name is Laura Timm and I am a PhD student at Florida International University. This is my fourth DEEPEND cruise and the data we collect from it will contribute to the last chapter of my dissertation.
I work on crustacean genetics. Specifically, I use the DNA of a few shrimp species to describe diversity and characterize how (or if) it is moving within the Gulf. These two things, diversity and gene flow, provide a lot of insight into the health and resilience of these target species. Most of my work with DEEPEND has focused on three shrimp: Acanthephyra purpurea is a bright red color and produces a bioluminescent spew to scare off predators.
Systellaspis debilis is also red (though younger ones can look orange), but with tiny light-producing organs called photophores polka-dotting its body.
Sergia robusta can be dark red or even purple and has photophores around its mouth and tail.
To me, all three are uniquely beautiful.
My research focuses on questions related to genetic diversity, which is a good metric for species health. Where is the most diversity found? Has this changed since 2011? How is diversity distributed? Is some genetic diversity unique to certain places? Answers to these questions provide unprecedented insight into how the Gulf copes with disturbances.
Now, a little perspective.
We trawl with a MOC10 net. It is very large. Every person on the ship could go stand in the frame of the net. However, when compared to the size of the ocean, it is tiny – it has been described as the equivalent of investigating terrestrial diversity using just a butterfly net. Yet, we still catch thousands of shrimp. Of these thousands of shrimp, a few hundred are targeted (A. purpurea, S. debilis, S. robusta). Of these hundreds, 96 are sequenced (this is due to the sequencing process; I can only sequence 96 at a time). The genomes of these species have not been sequenced, so I target a few thousand base pairs of DNA. A few thousand base pairs out of billions of base pairs. About 100 shrimp out of hundreds, hundreds out of thousands, thousands out of every shrimp in the Gulf. This tiny amount of data (which, in the history of science, is unprecedentedly large) can tell us so much about the animals living in the Gulf and how they came to be there and whether they are likely to survive whatever comes next.
Written by Rosanna Milligan
It’s the end of another successful cruise and we’ve collected thousands of animals and taken hundreds of physical and chemical measurements across the northern Gulf of Mexico. My job is now to take these data, integrate them with the data from our previous research cruises, and analyze them all to try to find patterns in them that will help us understand how the deep pelagic fish communities are structured.
Understanding how animals are distributed through different environments is one of the key questions in ecology, because the answers can tell us important information about which areas might be particularly valuable. This might be because they contain particularly high biodiversity and are important to conserve, or they might be areas that might contain particularly high abundances of animals that we might want to target for fisheries or drug development for example.
While it’s easy to imagine different terrestrial environments, like deserts, forests or mountain ranges, it’s much harder to imagine what the different environments that might exist in the open oceans are, because, frankly, one patch of seawater looks much the same as any other at first glance. But, when we start looking with scientific instruments like CTDs, or using satellite imagery, we can start to see how the oceans are structured by gradients and boundaries in the physical and chemical properties of the oceans like temperature, salinity or water currents. However, we still don’t really understand is how much this environmental variability influences the animals that live in the deep pelagic oceans. Do they care about different conditions or are they happy to live anywhere? Are they just pushed around randomly by water currents or do they actively swim against them to stay in the best locations?
CTD Instrument used to measure the physical properties of water and to collect water samples from different depths.
Our work with the DEEPEND project is starting to disentangle some of these ideas. For example, we’ve been working hard to figure out how to identify different water masses in the Gulf of Mexico in an ecologically-meaningful way, and separate out how and why different water types affect different deep-sea animals and their distribution patterns. We’re working with teams of geneticists, chemists and oceanographers too, to match up all the different research strands into a coherent story. All of this will be really important in understanding how resilient or vulnerable different organisms might be to human impacts in the Gulf of Mexico, in case something like the Deepwater Horizon disaster ever happens again.
So all the work we do at sea is really just scratching the surface of the work we do when we get back. We’ve got lots more work to do and many more questions to answer!

Written by Tess Rivenbark
My name is Tess Rivenbark and I am representing the Optical Oceanography Lab at the University of South Florida College of Marine Science. Most of the scientists here focus on biology, but my job is to collect data that ties this biology to the physical processes happening in the ocean, looking at different types of particles in the water.
With the CTD, I collect water samples and then filter them to measure chlorophyll and colored dissolved organic materials. Here is a picture of the CTD as it is being deployed from the ship. We send it down to 1500 meters collecting water samples along the way at various depths and measuring the physical properties of water such as temperature, salinity, and dissolved oxygen.

Another instrument I use, a spectral backscattering sensor, is known to the other scientists as the "fish disco" because it emits multi-colored lights. It measures how these lights bounce, or scatter, off of particles in the water.


My last instrument, a handheld spectral radiometer, measures the sunlight that reflects off the water. This is the same thing that many satellites orbiting the earth, like the Aqua MODIS, are measuring. We use the data we collect out here on the water to help understand what the satellite measurements tell us about the particles in the water. The two photos below show this instrument in use at sea and below that is a satellite image showing the concentration of chlorophyll with our proposed cruise track and sample stations plotted on top.



For centuries, sailors and scientists have observed birds landing on ships. A ship out at sea is like a moving island in the ocean. Various birds may seek refuge on ships, especially when storms occur, or are attracted to the lights of the ship at night. It makes sense that many of these birds are sea birds, but a number of land birds may make migrations across ocean areas or get blown out to sea by storms along the coast. Given the several storms during our cruise, it is no surprise we have had a number of birds land on or fly close to our ship, while it was 100-150 miles off the coast of Louisiana, Mississippi, and Alabama. So, here is a short rundown of the birds we have seen recently…
Purple Gallinule – spent a couple days resting on one of the deck cranes until it took off.
Louisiana Waterthrush – this wood warbler took refuge in a corner of the deck for a while before flying away.
Northern Oriole – just showed up on the ship superstructure, rested for an hour, and took off.
Cattle Egrets – we have had several stay around the ship, with a flock of 14 circling the ship one morning.
Bobolink – a few individuals flew around the boat this morning and one perched on the anchor chains and other structures on the bow.
Barn Swallows – One morning just before another squall, there was a flock of approximately 100 circling the ship from 5-6 AM. A flock of about 8 flew by the ship yesterday after several days of clear weather. This morning 3 were perched on some fixtures.
We also had a very large flock of a small birds that might have been American Goldfinches, but it was too dark at 4-5 AM to see them clearly.
Coastal birds we have also seen far out at sea include…
Osprey – one landed on a container on the forward deck, sat for a few minutes, and then left when it was disturbed by a crew member.
Brown Pelicans – three juveniles paddled along with the ship and flew short stretches to catch up again.
Caspian Tern and Royal Terns – one Caspian and two Royals sought a perch on a part of the stern of the ship during a rain storm.
Laughing Gulls – 3 juveniles and 1 adult stayed around the boat for a day during and immediately after a storm.

Studying the animals in the deep sea within their natural habitat is very difficult. It often requires sophisticated instruments or equipment and scientists have to be careful to make sure that they don’t disturb the animals they are studying. During the DEEPEND cruises, we use sound to study how animals move through the ocean and the daily movement patterns as they go up and down from the surface at night to the deep sea during the day. Using sonars, we can create a picture of where the animals are by measuring how much sound they reflect. While this gives scientists a broad picture of where the animals are, it does not provide enough detail to look at the individuals within the layers.
During this cruise, we have been using a new tool to study fish and invertebrates down in the depths of the ocean. We have attached an autonomous sonar (WBAT- WideBand Autonomous Transceiver) on to the MOCNESS (see photo above) to look at the animals that are near the net. This new sonar provides much higher resolution data at small scales, kind of like an underwater magnifying glass. With this new instrument we can look at the individuals that are being collected by the MOCNESS and then compare this back to what we see on the ship’s sonar. So far we have noticed that the animals do not seem to avoid the net as we expected they would.

This is my first research cruise in over ten years, and I am quite excited by the great opportunity. I once went out to sea fairly routinely when I worked at Harbor Branch Oceanographic Institution (HBOI), but the goals were much different then. This time for DEEPEND, we focus on the pelagic mid water column organisms in the Gulf of Mexico, which remains a fairly new habitat for me to explore.
My role for DEEPEND on this DP05 cruise is to ensure proper collection of new bacterioplankton samples from Gulf of Mexico seawater at various depths. I am basically following the same procedures as past cruises for consistency.
The main instrument for collecting water is the CTD (conductivity, temperature, and depth) which is loaded with a rosette (circular arrangement) of twelve Niskin bottles that can each hold 12 L. These traditional aquatic water collectors close at precise depths which I can control from the ship. R/V Point Sur crew member, Marshall Karmanec, helped get me accustomed to running and deploying the CTD on this cruise. With the controls, I can designate where and when bottles are opened at specific depths. Once the bottles are filled and back on deck, I am able to drain 4-5 L of seawater and bring them into the lab. I share a filtering station corner of the ship’s lab with FWC/USF technician Tess Rivenbark. While most of the other DEEPEND scientists are identifying charismatic deepwater megafauna, I filter marine microbiomes onto special sterile 0.45 micron filters. “Sterile” is the operative word here, since the lab is not the optimal place for traditional “microbiology” methods. Essentially I am preserving the communities on the filter by careful handling, freezing and recording, so they can all be brought back intact to my molecular lab at the NSU Oceanographic Center for DNA extractions and sequencing that will eventually illuminate the distribution and dynamics bacterioplankton in much greater detail.
The CTD also measures where the very important oxygen minimum and chlorophyll maximum zones occur vertically within the water column. These zones represent important parameters for oceanographic work since they can delimit where food chains begin or end, where maximum photosynthesis (the production of oxygen from cyanobacteria) happens, and we also have found distinct microbial communities (also known as “microbiomes”) associated with each zone. With DEEPEND postdoctoral scientist Cole Easson, we have been characterizing these microbiomes from past cruises, and our current results point to significant depth stratification of microbiomes in DEEPEND Year 1 data, which among other interesting findings will be submitted in a forthcoming manuscript. This year 3 sampling adds to the temporal dimension of the project and is also very exciting.

On every cruise, it’s tradition to send decorated Styrofoam cups down on one of the instruments to shrink them. Styrofoam is mostly air, so when cups made of Styrofoam are sent to the depths, as the pressure increases with depth, the air inside the cups is compressed, and the cups shrink accordingly. Once they shrink, they stay that way, as Styrofoam isn’t particularly flexible – it doesn’t expand again when it comes to the surface. This year, we received a set of beautifully decorated cups from Theresa McCaffrey’s Advanced Art Classes at Tualatin High School. Ruth Musgraves, who developed and runs our Creep into the DEEPEND summer camps (http://whaletimes.org/?p=2186) has a daughter in one of these art classes, and they heard about the shrinking cups through her. They send out a box of cups, and the artwork is quite amazing, as you can see in the photos below. The best part is that they made some cups for us as well.
I’m really thrilled about that, because I’m pretty much still at the stick figure level when it comes to my artistic endeavors.
There is a pretty careful protocol that we must follow to package the cups, so that the cups shrink without collapsing inside of each other as they shrink at different rates. If two cups shrink together, one inside of the other, they’re almost impossible to get apart without breaking one. They must be loaded in mesh bags with open ends facing each other, with each row separated by tie wraps so they don’t float together and collapse together.
We can load 14 cups per bag, and two bags per CTD rosette. The CTD rosette is deployed to collect water samples at various depths, monitoring conductivity (C – as a measurement of salinity) and temperature (T) as a function of depth (D). We have to be careful that the bags do not interfere with any of the sensors or closing mechanisms on the bottles, so we never load more than two bags per deployment.