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By- Heather Judkins
Well, that's a wrap! We finished processing our last station in the wee hours of Friday morning and headed bock to Gulfport, MS. It's been quite a successful trip with many new finds and exciting new questions to look into as we continue to explore this region of the Gulf of Mexico!
At the last station, we had quite a haul of crustacean species as well as lots of hatchetfishes- both of which scatter sound. We did acoustic work using the multibeam sonar to locate the DSL and towed the MOC10 system within these layers to get an idea of which animals may be found. This region is of the ocean is important because it represents the transfer of energy from the upper epipelagic to the deeper benthic systems. Many of the fish and crustaceans in the DSL are prey for benthic invertebrates and predatory fishes. (see Haley G's blog for more on acoustics).
Various hatchetfish species and lots of crustaceans collected at the last station
Friday was a flurry of activity with packing up the lab, washing down the nets, and preparing samples for their journey home.
Nets drying out before being packed up with the R/V Point Sur in the background.
We could not have done any of this without the amazing work by the R/V Point Sur crew which included feeding us morning, noon, and night; celebrating birthdays with us, and providing a safe and successful trip all around. This is the last of the three DEEPEND/RESTORE cruises for this grant award and now we switch to analyzing all the data we've collected and producing products in the next year that can be used by resource managers.
This morning, the DEEPEND team members packed up their vehicles and made their way back home with so much to work on- Until the next time!
DEEPEND Team photo
By Tracey Sutton
As we churn towards the finish line of another successful DEEPEND cruise in the offshore Gulf of Mexico, we take a pause to appreciate some new milestones. One of these is our 250th deployment of the 10-m2 MOCNESS pelagic trawling system, which has been the workhorse of DEEPEND. With six nets on each deployment, that means we have collected over 1500 pelagic trawl samples during our DEEPEND time series. Despite its status as the largest sample set of its kind, what continues to amaze us the most is that we continue to observe and collect NEW THINGS on every cruise. This one has been no exception.
We began the cruise by sighting an orca, then watched in wonder as a family of roughtooth dolphins used our ship lights to feed on flyingfishes in the middle of the night, and the just today saw a very large, silver fish leisurely swimming under the boat while we drifted with the afternoon breeze. Our best guess was that it was a louvar (Louvaris imperialis), a pelagic fish exceeding 6 feet in length and 330 lbs in weight. Our sampling has collected some incredible specimens of pelagic shrimps, dragonfishes (pictured), lanternfishes, eels, and one of my favorites, a whip-nosed anglerfish (pictured). We find that every trip out only makes us want to explore this miraculous ecosystem more. Tomorrow we will sample our last oceanic station and then head to a site over a deep-water coral complex to investigate pelagic-benthic coupling along the outer continental shelf.
I am so proud to be associated with the wonderful DEEPEND team.
By Lisa Rose-Mann
Hello again! I’m Lisa Rose-Mann and I’ve made it back on the R/V Point Sur for my second cruise with DEEPEND. YES! My research focuses on contaminants in the tissues of animals from the Gulf of Mexico. I am analyzing the stomach contents of Yellowfin Tuna (Thunnus albacares) and Blackfin Tuna (Thunnus atlanticus) and the fish themselves to discover if any persistent organic pollutants (POPs) like, polycyclic aromatic hydrocarbons (PAHs), polychlorinated biphenyl (PCBs), pesticides, and phthalates are present in their muscle or liver tissues. I use a method developed by Dr. Isabel Romero for the GC/MS/MS to detect these compounds in the tissues. The Gulf of Mexico has an enormous watershed which can bring many of these compounds to the ocean from runoff and PAHs occur both naturally and as a result of oil spills. It was especially striking for me on this trip out to see the marker on the navigation chart where the Deepwater Horizon oil platform once was. I couldn’t help but to take some time to reflect on what happened thirteen years ago and try to imagine what that must have been like out here on the water. The effects of the spill are still being studied by many scientists including myself.
Me and a squid from dissections; Dr. Isabel Romero and I in the lab.
Over the past year I have been very fortunate to be a NOAA Gulf B-WET (Bay Watershed Education and Training) fellow. I’ve been able to bring science to the classrooms of 3rd, 4th, and 5th graders of some Title I schools in St. Petersburg, FL. They have really enjoyed the program and the specimens I’ve been able to introduce them to. After a few visits to the classroom and their own atmospheric observations they come to The Clam Bayou which is an Education and Outreach center for the USF College of Marine Science. There we provide an experiential learning experience for the kids in their own watershed. We take the kids fishing with the seine net, teach them about the importance of mangroves and explore a fresh plankton sample under the microscope, my personal favorite. I’ve already shared with them that I am on this cruise, and they are all watching the ship tracking and blogs. I’m really hoping to be able to connect with them online while I’m out here and introduce them to some of the coolest scientists I’ve been able to work with so far. And I really can’t wait to share some of these unique animals with them too! Shout out to Betsy, Kate, Nash, and students!
Photo of students (and me with them bottom left) at The Clam Bayou observing plankton.
And while those awesome kids are pretty far away from me right now, I cannot help but notice the little kids we all are on the inside in each of the scientists on board this vessel. The awe of each net’s product, the joy of discovering something never seen before, the ah ha’s shouted as the number of fin rays distinguishes one species from another. I can see it in their eyes, their smiles and utter passion for what they do. I always admire their endless conquest to answer some of those questions we carry forward from our own childhood curiosity…what is that, what’s that for, and why.
Photo of the MOCNESS (Multiple Opening-Closing Net and Environmental Sensing System) as it arrives to the deck.
Hi Everyone! Haley Glasmann here, and I am back on the R/V Point Sur for my second DEEPEND research cruise. I’m a PhD Student in the Marine Ecology and Acoustics Laboratory at Florida International University, and I’m here with my advisor, Dr. Kevin Boswell. Our role on this cruise is to set-up and monitor the scientific echosounders. It takes a lot of work upfront to prepare our acoustics for deployment in the field, but all the hard work is worth it!
Haley Glasmann and Dr. Kevin Boswell assembling “The Pod.”
Dr. Kevin Boswell, Haley Glasmann, and Dr. Heather Bracken-Grissom with “The Pod” assembled after a hard day’s work.
The use of active acoustics in otherwise hard to reach marine systems, where video data and diver surveys are infeasible, can provide information about distribution and behavior of organisms. Every 5 seconds, we get 1 pixel of information. As the ship drifts along, we get an echogram, which allows us to visualize our data in real time! An 18kHz echogram is shown below, with depth on the y-axis and time on the x-axis. The brighter colors are indicative of the deep scattering layer community, and the yellow line represents the CTD track. Around 19:45 you can see the upward diel vertical migration, where organisms are moving into the upper water column for the night to feed. Mounted on the CTD is our Wide-Band Autonomous Transceiver (WBAT), which allows us to send an echosounder to depth. Integrating the ship mounted echosounders with that of the WBAT allows us to discern individual organisms within the deep scattering layer.
Although the image below may just look like a bunch of rainbow blobs, the community in question is generally referred to as mesopelagic micronekton, ranging in size from 2-20cm, comprising fishes, siphonophores, crustacea, and other zooplankton. Many of these organisms take part in the diel vertical migration and play a key role in oceanic carbon cycling, moving between two to six billion tons of carbon per year. Mesopelagic micronekton are also valued for their use as “potentially consumable protein,” some countries already target them for use for aquaculture fish feed, and for use in pet food.
18kHz echogram with WBAT echogram inlaid.
The Gulf of Mexico is a mesopelagic diversity hotspot, and I aim to further investigate how these organisms are arranging in space and how that changes as they move vertically. Learning more about the mesopelagic micronekton will allow us to develop a better understanding of niche partitioning in the deep-sea, as well as being informative for fisheries management.
A few mesopelagic micronekton that were caught in the MOCNESS (Multiple Opening-Closing Net and Environmental Sensing System).
To keep up with more of my acoustic adventures, follow @scubahaleykat and @boswelllab on Instagram!
Greetings, fellow deep-sea enthusiasts! I'm Pedro A. Peres, a postdoc at Florida International University, and I'm back with my second post on the blog. Today, I want to talk about an exciting new technique that is revolutionizing the way we study deep-sea environments: environmental DNA (eDNA).
Traditionally, to analyze the DNA of marine animals, we would collect and extract tissue samples directly from the animal. But what if we could get DNA samples without even seeing or sampling the animal? This is where eDNA comes in. Every living creature in nature releases DNA molecules in the environment through various means like skin, mucus, feces, and more. Scientists have discovered that we can extract and sequence these DNA fragments to detect specific species or assess community composition, all without ever having to interact with the animals directly.
In DEEPEND|RESTORE, Dr. Bracken-Grissom and I are working with Jonah Ventures (ww.jonahventures.com) to use this amazing technique focusing on deep-sea environments. The main challenge is that eDNA is a relatively new method but even newer for deep-sea environments. Many of the references available investigate freshwater or shallow waters, which have different features than the deep sea. This means that replicating their sampling method might not be ideal for the deep sea. For instance, animals in the deep sea are more spread out than in other environments, so should we filter more water to have a fair representation of the community we are investigating? Can we use acoustics to guide where to fire the CTD to collect water? And many other questions that we are thrilled to investigate!
On this cruise, PhD candidate Stormie Collins is in charge of filtering the water, preserving the filters, and logging the CTD data so we can analyze everything later. She and I assembled a cool eDNA setup provided by Jonah Ventures, and Dr. Kevin Boswell and PhD student Haley Glasmann are helping with the CTD. Teamwork! I’m excited to see our findings and what eDNA can reveal to us about deep waters.
Hi everyone! DEEPEND science is so exciting that even the whales are following us! Just wanted to share that some of our team were lucky enough to catch a glimpse of an Orca today! Even though it was a bit far from the vessel, a few pictures and video were captured.
As rare as they are to see out here, it is thought that there are some resident Orcas that live here in the Gulf of Mexico.
We will be keeping our eyes open when we are out on deck as the sea state is perfect for more whale sightings!
Hi! My name is Stormie Collins, and I am a PhD candidate at Florida International University. I have been involved in processing samples collected from DEEPEND|RESTORE cruises since 2019, however, this is my first time getting to go to sea with the group! I am largely interested in the way that organisms perceive the world around them, and the associated adaptations they have evolved to survive within their environment. In the deep-sea, many organisms utilize bioluminescence; a process through which a chemical reaction produces light. My dissertation focuses on vision and bioluminescence in deep-sea shrimps. Being able to see the animals freshly collected allows me to observe color as they are in life and provides a better opportunity to consider bioluminescence across species as many light organs become invisible after animals are placed in preservative.
Shrimps can be bioluminescent through dermal light organs called photophores, internal photophores that arise as a modification of the hepatopancreas, or through a luminous secretion, which may also be referred to as “spew”. Among decapod shrimps, luminous secretions are most common, and many species use this as a defense mechanism to evade approaching predators. Dermal photophores are embedded within the cuticle and are obvious. Internal photophores are obvious in sergestid shrimp (see below), however, they are also present in other shrimps, where they are much easier to overlook, particularly in red pigmented shrimps. The caridean shrimp Plesionika richardi is documented to have internal photophores, however, they have never been previously observed in this species by our team. Upon collection of 2 P. richardi, observation of internal photophores were indeed confirmed (see below), and when looking for them, are obvious. It is likely that this has been overlooked as the red pigmentation sort of masks the internal organs and they are no longer visible in preserved material.
The most up-to-date count of bioluminescence depicts 94 independent origins across the tree of life, making this perhaps the most common form of communication on the planet. Though our current understanding of bioluminescence in shrimps with both dermal and internal photophores suggest they are used for counterillumination camouflage, I believe that the functional role of bioluminescence should be considered separately for each species. The presence of internal photophores in P. richardi provide an excellent example of how underestimated and overlooked bioluminescence may be in decapod shrimps, as well as many other marine organisms.
P.s.- the view from the ship is NOT too shabby ?
Hi everyone! My name is Natalie Howard and I’m a master’s student in Dr. Jon Moore’s lab at Florida Atlantic University’s Harbor Branch Oceanographic Institute. This is my first time participating in one of the DEEPEND/RESTORE cruises and I am very excited to be here! I was introduced to the project while pursuing my undergraduate degree at the University of South Florida. While I was there, I helped Dr. Heather Judkins with pteropod data, and she introduced me to Dr. Jon Moore, where I now work with fish collected from the cruises.
This is an image of Melamphaes suborbitalis. It’s one of the larger Melamphaes, with an average standard length that’s over 90 mm! It also has a small spine on the top of its head, which is a distinguishing trait of this species.
My thesis project is focused on vertical migration and diversity of Melamphaes (Melamphaidae). The Melamphaes fish we find in the Gulf of Mexico are relatively small, averaging between 20- and 30-mm standard length and are dark brown in color. These fish reside in the meso- and bathypelagic zones during the day but will migrate into shallower waters at night to feed and avoid predation. This behavior is referred to as diel vertical migration, which I will be investigating as part of my research project. There have also been many recent taxonomic revisions of the family Melamphaidae, so I’m hoping that we find one of the newly identified species on DP09!
Yes, you guessed it! It’s time for another DEEPEND cruise in the Gulf of Mexico! Vans are loaded and being driven to Gulfport, MS, gear is packed. scientists are scrambling to make sure we have everything we need, and everyone is traveling in the next day or two to arrive in Gulfport for another successful adventure.
Our current plan includes loading all the gear onto the R/V Point Sur on Monday and depart from Gulfport, MS at midnight. We will be heading to our usual stations for collecting samples from 0-1500 m deep using the MOC10 net system once again. This will be our 9th DEEPEND cruise and the 3rd as part of the NOAA RESTORE program which concludes next year. We are very excited to keep this long-term survey going as we still know so very little about the deep ocean we are exploring.
We will be posting blogs along our journey once we get underway so stay tuned!
Have you ever wondered how animals communicate, find food, mates and defend themselves in complete darkness? The answer is that most deep-sea animals have evolved the ability to produce their own light, and this is called bioluminescence. Most deep-sea creatures either have all the machinery to produce bioluminescence themselves (examples include fish and crustaceans), while others form a unique relationship with glowing bacteria that live in their light organs (example include squid and angler fish). This results in a beautiful underwater display of flashes, sparks and glows, much like a fireworks display on the 4th of July. However, in the deep-sea, where food and mates are limited and predators lurk in complete darkness, this light show is not for fun. The stakes are high, and this underwater “language of light” is critical for the animal’s survival.
During this cruise we have witnessed some incredible examples of bioluminescence which I am excited to share with all of you.
Deep-sea flashlights: Do you see all those beautiful dots of purple and red? Those are called photophores, or light organs, which glow in the dark. Much like a flashlight they can turn on and off when needed and can be tuned to match the brightness around them. In many cases they are found along the entire surface of the animal’s body and can be used to lure in prey (oh, something shiny!!), defend themselves (ahhhh, too bright!!) or communicate with others of the same species (hey, you see me over here, what is yourrrrr name?). Below, you are looking at a loosejaw fangfish (Aristostomias) and Viperfish (Chauliodus sloani). One has a bring red light organ below the eye and the other has light organs all over!
Photos: H. BRacken-Grissom
Glowing blue vomit: Did you know the deep-sea shrimp can vomit a bright blue glowing mucus? Yep, it is true, and they do this to protect themselves when they get scared. Ingenious, huh? Below, you are looking at a deep-sea shrimp by the name of Notostomus gibbosus. When startled, this deep-sea beauty will secrete a blue smokescreen that will stun a predator while they tail-flip backwards to escape. Gooo team shrimp!
Photo: H. Bracken-Grissom
Wonder what it looks like? See below....
Photo: Sonke Johnsen
The Language of Light: We know very little about how dee-sea creatures use bioluminescence to communicate due to the difficulties of studying these creatures in their natural habitat. However, it is possible that these beautiful multi-colored barbels could be the clue. Do these help find mates? Do they lure in prey? Both? I assure you we are going to have some fun exploring and trying to solve the many mysteries that the deep-sea holds. Until next time…….
Photo: H. Bracken-Grissom
By Daniel Hahn, NOAA
When the BP Deepwater Horizon oil spill happened more than a dozen years ago the thought of so much oil impacting the deep sea had not been considered thoroughly enough to fully comprehend the impacts. With the depth of the release nearly a mile below the surface, the high pressure of the release and the application of dispersants at the well head, a large portion of the oil remained trapped in the deep sea. As the strategy advisor for the offshore water column injury assessment, I worked with an incredible team of biologists, modelers, project managers, and more to develop a sampling plan to investigate the impacts of the oil spill on the waters of the Gulf of Mexico and the animals that inhabit them. Dozens of offshore sampling missions were part of the investigation and one of the main goals was simply to document what was in the deep waters of the Gulf. We had limited understanding of the diversity, distribution and abundance of the deep sea animals.
Fast forward a dozen years and I am finally offshore in the Gulf of Mexico seeing these animals on board the ship as they come up from the depths. While looking at pictures is great, there is something extra special about seeing the animals first hand. Looking at teeth, scales, spines, eyes, and photophores under a microscope shows just how beautiful and amazing these animals are. Because of the lack of light where these animals live, many are black, red (red light doesn’t penetrate very deep into the sea), or clear. Clear animals always amaze me.
Now for a quick comparison of how I identify with a couple of the animals that I had the privilege of being able to observe as they were brought up from the depths of the Gulf of Mexico:
The Angler has a lure attached to its body to attract its prey. While I don’t have a lure attached, I once spent a year fishing only with flies that I tied from my own mustache hair.
The first Angler I saw aboard the DEEPEND RESTORE cruise on the R/V Point Sur! Insets: Mustache fly and tripletail caught on mustache fly. (Photo: D. Hahn)
The Swallower eats big meals. Since I typically don’t eat breakfast, and have been known to skip lunch too, with three great meals a day on board the ship, I feel a bit like a Swallower.
I feel like a Swallower after three big meals a day! (Photo: D. Hahn)
While we certainly hope that we don’t have another major spill like the Deepwater Horizon, there is always a chance. Additionally, there have been several smaller spills that have occurred in the depths of the Gulf in the last decade. In order to understand how these deep-water spills impact this incredibly diverse assemblage of fish and invertebrates, long term investigations such as this DEEPEND RESTORE project are crucial.
Hi everyone! My name is Haley Glasmann and I am a second year PhD student in Dr. Kevin Boswell’s Marine Ecology and Acoustics Laboratory at Florida International University. I am very excited to be here on the R/V Point Sur on my first ever scientific research cruise. Dr. Boswell’s lab focuses on using active acoustic a.k.a. SONAR (Sound Navigation and Ranging) technology to understand the processes that mediate behavioral and distributional patterns in marine organisms.
As part of the DP08 cruise, we are using ship-mounted echosounders to observe the deep scattering layer community. The “Pod” is where we have echosounders operating at frequencies of 18, 38, 70, 120, and 200 kHz. Having multiple frequencies helps us characterize the water column based on the acoustic response (echo) of individuals and/or the aggregations that are dispersed under the pod during data collection. This data is shown to us in real time, which allows us to inform where to deploy our WBAT (Wideband Autonomous Transceiver) and MOCNESS (Multiple Open/Closing Net and Environmental Sensing System). The WBAT (that we affectionally also call the “wombat”) is currently fitted with a 38 and 200 kHz transducer operating in wideband and is mounted to the CTD (Conductivity, Temperature, and Depth) profiler, which travels through the water column down to depths of 1500m. With the ability to bring the WBAT/CTD into the scattering layers themselves, we can collect high resolution data on the individual scattering types (organisms) present within. For my dissertation, I am interested in using the WBAT data in tandem with the ship-mounted echosounders to analyze the spatial arrangement and density of scatters within different parts of the layer. Fine scale interpretation of the community that undergoes diel vertical migration has important implications for developing an enhanced understanding of carbon cycling in the open ocean and mesopelagic fisheries management
The acoustics lab and Haley deploying a CTD array (Photos: Haley Glasmann)
A typical “day” on the R/V Point Sur for me begins at about 4:30pm, let’s hear it for the night shift! First order of business is programing the WBAT for deployment on an evening CTD cast. I then eat dinner for my “breakfast” while the unit is collecting data. At about 8:45pm, we retrieve the CTD/WBAT back on deck and then the crew prepares to deploy the MOCNESS. During the night I monitor the ship-mounted echosounders, keeping a close eye on computer processing and power supply to ensure we are continuously collecting data. Other parts of the night include catching up on reading, replying to emails, jamming out to my Spotify playlists, making Styrofoam crafts (check out my shrunken head!) and the best part of all- seeing all the deep-sea creatures that come up in the MOCNESS around 3am. As the sun rises, I prepare to end my day with another CTD/WBAT deployment and enjoy a savory breakfast of bacon, grits, and biscuits from Chef Mike! …and after that at about 9am, time to get some rest!
Styrofoam head before and after CTD deployment down to 1000 m (Photos: H. Glasmann)
Interested in keeping up of my graduate school adventures and the Boswell Lab? Check out @scubahaleykat and @boswelllab on Instagram for more!
Thanks for reading!
Haley K. Glasmann
By Jon Moore
While this DEEPEND RESTORE project is focused on deep-sea animals, we are also exploring linkages between those deep-sea animals and other marine life out in the ocean. One of those links is with the oceanic bird fauna. Some oceanic birds (petrels and storm-petrels) are known to feed on the mesopelagic fishes and squids that migrate to the surface at night.
A ship out at sea is like a moving island in the ocean. Especially when storms occur, various birds may seek refuge on ships or are attracted to the lights of the ship at night. During a thunderstorm yesterday, we had two Cliff Swallows visit the ship. So, we are doing observations, when possible, to see what birds are visible from the ship.
The first thing we noticed is that we have a few hitchhikers that have decided to stay on the vessel as a convenient place to rest and launch feeding excursions into the surrounding waters. A juvenile Brown Booby and a juvenile White Ibis have each taken residence on the ship. The ibis is wandering around the decks and poking around in various holes and crevices. The booby perches on the ship’s anchor and is sometimes joined by other brown boobies (at least one other juvenile and 2 adults over the past week). A Masked Booby has perched on the bow a couple of times. When the ship disturbs a group of flying fishes, these boobies launch themselves quickly and swoop down to catch those flying fishes while they are gliding over the water.
Other birds we have seen this past week include Royal Terns, Sandwich Terns, Laughing Gulls, Magnificent Frigates, Leach’s Storm Petrels, and Audubon’s Shearwater.
Left to right: Brown Booby (Photo: LRose-Mann) Juvenile White Ibis (Photo: H Judkins) Masked Booby (Photos: J. Moore)
My name is Pedro A. Peres and I am a postdoc at Florida International University working with Dr. Heather Bracken-Grissom. The focus of my research is to use genomic methods to understand how fish and crustacean species' DNA has changed over time after the Deepwater Horizon Oil Spill.
This is my first DEEPEND|RESTORE cruise and I am more than thrilled! The DEEPEND|RESTORE group has done amazing work in the past years, and we know for a fact that many deep-sea species populations are crashing. But what does genetics have to do with this? Everything! Genetic diversity is expected to follow population size changes, and it represents the potential of populations to deal with environmental changes (higher genetic diversity = higher potential to respond after disturbances). Therefore, if population abundances are declining, can we detect changes in genetic diversity? If the genetic diversity is declining, species might not be able to survive after a future potential disaster. For this cruise, I am in charge of making sure that all fish specimens are being preserved in the right way for the many genetic analyses we want to do. This means preserving specimens or tissue, writing labels, flash-freezing specimens in liquid nitrogen, sterilizing materials, and changing gloves all the time (haha). If I have a little time, I go bug HBG to look at some of the cool crustaceans we are also collecting. So far, we have more questions than answers.. but I’ll be back in a future post!
Pedro sampling a whalefish (Photo: H. Bracken-Grissom) and a dragonfish that is waiting to be processed (Photo: P.A. Peres)
Besides all the scientific experience, I celebrated my 30th birthday on board and had a surprise party! Who else can say they spent their 3.0 birthday in the middle of the Gulf of Mexico, with lots of cool creatures and amazing people? For sure an experience I will remember for a long time.
Happy Birthday to Pedro! (Photo: A. Cook)
By Dante Fenolio
Sea cucumbers are echinoderms – related to starfishes and sea urchins. Sea cucumbers have an interesting body plan that includes something known as a “respiratory tree.” The respiratory trees are highly branched systems (two per animal on either side of the sea cucumber) that take water in and out through a cloacal pore. The flow of water is used in respiration. Now consider the “pearlfish.” These fishes are a moderately diverse assemblage – but they have one thing in common… they inhabit the digestive tract of sea cucumbers. They use the water flow going in and out of the sea cucumber to locate the cloaca… then they swim right in. Often times these fishes live alone but sometimes, a pair will live together within the same sea cucumber. One group of pearlfishes harm their host by consuming their gonads and other internal organs – a truly parasitic relationship. But with the rest of the pearlfishes, the fishes do not do any harm while the sea cucumber serves as a home base.
Pearlfish collected on DP08 in the Gulf of Mexico (Photo: D. Fenolio)
The "Tongue Eating Isopods" are a group of isopod crustaceans that inhabit the mouths of fishes as adults. This "Tongue Eater" is of the family Cymothoidae and is of the genus Cymothoa. Ispods of this genus all start life as males. If they are lucky enough to find their way into the mouth of a fish (lots of larvae in the water column - perhaps larvae grab onto small fish and move into a larger fish when the small one is eaten?). Once they do get into the mouth of a fish, they latch onto the tongue with sharp grasping legs. They tighten their grip of the tongue and cut circulation. Ultimately, the tongue rots away except for a stub at the floor of the mouth. The isopod will spend the rest of its life living in the space where the tongue of the fish was and holding onto the "tongue stub." Presumably, the isopod helps itself to bits and pieces of food as the fish eats. We found this individual within the remains of a large flying fish that was itself in the gut of a Mahi Mahi (Coryphaena hippurus). We assume the isopod had replaced the tongue of the flying fish. The dorsal aspect is to the left, the ventral aspect to the right. If you look under the ventral aspect, you can see a pouch (a "marsupium") where this female had been brooding a clutch of developing young. All of these isopods start life as males. If they find a fish host and replace the tongue, they change to the female sex. Newly arrived males to a fish mouth will mate with the resident female - yes, in the mouth of the host fish or on the gill arches. Males typically inhabit the gill arches of the fish. Some sources argue that all isopods enter the fish through the gills, not the mouth. Observed on the Gulf of Mexico, July 2022 during DEEPEND-RESTORE work.
Tongue eating isopod collected from DP08 in the Gulf of Mexico (Photo: D. Fenolio)
My name is Hannah Johnson and I am currently pursuing my Master’s of Science degree in Marine Science under Dr. Tracey Sutton at Nova Southeastern University. I am lucky enough to attend my first DEEPEND/RESTORE cruise on R/V Point Sur this year. While the focus of my thesis project relates to the reproductive habits of the deep sea fish genus Chiasmodon (Scombriformes; Chiasmondontidae), my predominant purpose on this cruise is to help record the collection of all the deep sea fauna we find.
The MOC coming onboard from a night tow (Photo: H. Johnson)
I work with Dr. Rosanna Milligan and April Cook to weigh, measure, and preserve each specimen. We log the specimens into the database to be able to document various notes, along with the measurements, site collection, and much more.
It is extremely important that we ensure each speciment gets preserved properly as many scientists and students will use our specimens for projects, even years later. For example, the fish genus Chiasmodon I work with was caught and documents 10 years ago! Thanks to great preservation techniques, I am able to do kinds of analyses with their reproductive tract as well as gut and diet analysis by my colleague Travis Kirk.
We were able to catch a Chiasmodon sp. with a full stomach!
It has been an amazing experience to see first-hand what goes on during the DEEPEND cruises. It helps to give insight into how the lab specimens from years ago were collected.
Thanks for reading!
By Lisa Rose-Mann
Hi! I’m having a great time on my first research cruise. Having worked with samples from previous cruises I have longed to be able to join the DEEPEND crew. I really wanted to see the MOCNESS in action! This is a net system that opens and closes at different depths (for this cruise, 0-1500 m down). The diversity of life we are finding is amazing and I’m completely blown away by the cool deep sea creatures and their adaptations I’ve been able to see firsthand.
From left to right: Loosejaw, hatchetfish, viperfish, black dragonfish (photo: L. Rose-Mann)
My current research is performing chemical analysis on the tissues of squid and their predators for signs of contaminants from things like oil spills, pesticides, plastics and other persistent organic pollutants. As part of this crew I am collecting samples to bring back to the lab for that purpose.
Lisa processing a sample onboard (Photo: H. Judkins)
I’ve eaten really well on board, seen a lot of cool birds, taken my shot a Mahi Mahi (haven’t caught my own yet, but there’s still time) and learned a ton about these animals so far. Additionally, having this kind of time with some really amazing scientists and been very rewarding. I’m beyond thrilled to have had this opportunity and hope to find a way join the crew again in the future.
Our first stop!
This area is a deep water coral reef on the upper continental slope dominated by Lophilia species (a deep sea coral). We explored this area briefly last year to investigate interactions between the deep scattering layer and the benthic community. This year, we are visiting this site twice to continue exploration with our first MOC deployment and retrieval happening last night.
This is our most shallow site with a bottom depth of 450 m and we towed the MOC10 downslope heading deeper to a depth of 402 m as to not disturb any benthic communities. This was a night trawl so we expected many deeper-living animals coming to the epipelagic zone (0-200 m) as there is a nightly vertical migration of animals towards the surface to feed under the cover of darkness.
T. Frank and H. Judkins emptying the cod ends into buckets for lab sorting (Photo: L. Rose-Mann)
J. Moore, T. Sutton, T. Frank, H. Bracken-Grissom sorting species (Photo: L. Rose-Mann)
Once the cod ends were collected and sorted by the taxonomists, identifications were made of the various faunal groups (fishes, cephalopods, crustaceans). Highlights included our usual suspects such as eel larvae, a pseudo-oceanic hatchetfish species which is common in this habitat, Sergia hans jacobi (crustacean species), pteropods, and heteropods as well as some unexpected finds like a Star Eater fish and a snake-eel larvae that doesn’t match any known species at this time. Exciting stuff!
J. Moore holding an example of an eel larvae he identifies in the field (Photo: H. Judkins)
We are now off to deeper waters of the Gulf of Mexico for our next deployment- stay tuned!
Yeehaw! Almost time to shove off on our next DEEPEND/RESTORE cruise which will set sail tonight just after midnight on the R/V Point Sur. The team is busy stowing gear, repairing holes in nets, and making sure we have everything we need for the next 12 days. We will be deploying the MOCNESS net system as we have on past cruises and will be getting to out our first station tomorrow afternoon. We will be posting blogs throughout our journey so stay tuned!
Cheers- Heather J
R/V Point Sur, docked in Gulfport, MS (photo: L. Rose-Mann)
We are heading back to the dock today and can't believe the trip is almost over! All we have left is to enter data, clean the nets, clean and pack everything in the lab and disassemble the acoustics equipment- all by 8 am tomorrow morning! This post is all about the animals as we wanted to share just a few images of the amazing creatures we have collected during this trip.
We can't thank the crew of the R/V Point Sur enough for this safe and amazing research cruise. We also would like to shout out CSA, Continental Shelf Associates for our MOC10 operator, Gray- without him, we wouldn't have animals to work with! The support from our organizations and universities has been consistent throughout the DEEPEND program which we truly appreciate.
See you next year for our next adventure!
Right: Deep Sea Shrimp
Left: deep sea luminsecent squid
Right: Seven-arm octopus
Left: Atolla jellyfish
Right: deep sea crab on pyrosome
Right: Anoplogaster cornuta, Fangtooth fish
Left: Stylephorus chordatus
Right: Chauliodus sloani, Viperfish
Left: Serrivomer lanceolatoides, Sawpallet Eel
Middle: Zenopsis conchifer
Right: Omosudis lowii, Hammerjaw fish