Recent blog posts
Post by Ashley Marranzino
My name is Ashley Marranzino. I am an incoming PhD student working with Dr. Tracey Sutton. I am excited to be joining the fantastic team aboard the R/V Point Sur for my first DEEPEND cruise!
For this cruise I work predominately with “team fish” and help to weight, measure, and preserve every single fish specimen we collect after they have been identified. A range of scientists use the specimens we collect during DEEPEND cruises, so we make sure certain species are preserved appropriately for future analyses on topics like genetics, morphology, and diet.
Ashley Marranzino, April Cook, and Drew Mertzlufft process the fish specimens after every tow. Photo taken by Dr. Isabelle Romero
I am also in charge of recording all of the size and preservation information for each specimen in our database. This ensures that we can track everything we catch and that the specimens and data we collect at sea can be effectively used and dispersed to different scientists after the cruise.
After we finish sorting through and processing our catch, I have also been collecting data for my own research looking at the sensory biology and ecology of deep-sea dragonfishes.
The threadfin dragonfish, Echiostoma barbatum, is covered in bioluminescent organs called “photophores”. Image by Dr. Isabelle Romero.
Bioluminescent (light-producing) organs cover the head and body of these midwater predators. Scientists hypothesize that some of these organs are used to find food (like the elaborate chin barbels on many species that likely lure in prey) while others are used to camouflage the fish by producing light similar to that filtering through the waters above (called “countershading”). But we still do not know the function of other bioluminescent structures in dragonfishes. Since we cannot keep dragonfishes alive in aquaria or easily watch them in their natural environment, I am trying to infer the function of the bioluminescent organs by examining their structure and placement on the body.
Image by H Judkins
I am excited to get back into the lab and continue examining some of the beautiful dragonfish specimens we have collected this trip!
Post by: Heather Bracken-Grissom
Hi everyone! My name is Heather Bracken-Grissom and I am an Associate Professor at Florida International University. My lab studies crustacean systematics and genomics, but today I want to talk about life at sea. Ever wonder if we get a little stir-crazy living on a research vessel in very tight corridors? Well, the answer is YES, so we need to be creative in the ways we get our bodies moving. Not only do we find creative ways to exercise on the ship, we also need to work off ALL the delicious food (and goodies) Chef Michael is cooking up for us every day! Exhibit A below J
Photo: Chef Michael and lunch options! (Photo: HBG)
So today, I want to introduce you to some of the ways we integrate exercise into our daily routine. The ship is small, but the view is fantastic, so many of us take long walks around the upper deck. Integrate stairs into the mix for a little added challenge! Don’t be surprised to see a pod of dolphins or a sperm whale off the bow.
Heather J and April C. walking the 01 deck loop (Photo: HBG)
If you want to add a bit of cardio for those days we eat not 1, not 2, but 3 desserts (because breakfast, lunch and dinner dessert is a thing on this cruise), feel free to join me on the upper deck for a “Cardio Circuit” fitness class. This is only possible on days when the waves are not 5 to 7 ft and ideally flat and calm.
Heather BG in the middle of her cardio circuit (Photo: HJ)
If you can handle the heat (literally the room is about 90 degrees) the spin bike is always an option! This is a true luxury, as most research vessels are NOT equipped with these. The space is cramped, but WORTH IT.
Kevin biking away (Photo: HJ)
Lastly, we do get “some” exercise while we sample the amazing creatures of the deep sea. This is Danté and Tracey pulling in the large MOC10 nets we use to collect our critters. Believe me, this is no easy task. Those nets are heavy and will get your heart-a-pumpin!
Tracey and Dante with their daily upper body workout (Photo: HJ)
So, as you will see we can still get movin’ to the motion of the ocean and stay in shape, even at sea!
Post by Matt Woodstock
My name is Matt Woodstock and I am a PhD Candidate at Florida International University working under Dr. Yuying Zhang. The focus of my dissertation research is to develop computer models that simulate conditions we observe in the Gulf of Mexico and answer ecosystem-level questions about the ecology of the system. Examples of these types of questions are changes to food web structure as populations fluctuate over time, the influence of the Deepwater Horizon oil spill on the mortality rates of mesopelagic animals, and vertical nutrient transfer by vertically migrating fishes and cetaceans. Ecosystem-based modelling is rarely done in the oceanic zone because it requires a lot of data, but because of projects like DEEPEND these types of research questions are feasible. Previously I completed a masters under Dr. Tracey Sutton studying the diet and parasites of mesopelagic fishes in the Gulf of Mexico.
Dr. Boswell (right) and I (left) securing acoustic equipment to the CTD as a way to monitor fish behavior.
This is my third research cruise and second on the R/V Point Sur with the DEEPEND crew! My main job is to help Dr. Kevin Boswell gather our acoustic data by setting up gear and monitoring the data as it comes in. Aside from the few hours that we are moving between stations, we are constantly collecting acoustic data. I am also helping Dr. Isabel Romero collect and filter water samples for chemicals in the water column using a CTD. The acoustic and water chemistry projects are collaborating by placing an automated acoustic transducer on the CTD and collecting water at the same time that the deep scattering layer (a collection of deep-sea organisms in the water column recognizable through acoustic receivers) moves by. Being out at sea is one of my favorite things to do as a scientist and each time is special!
Left: Dr. Romero (left) and Dr. Boswell (right) deliberating on the best game plan for sampling.
Right: My main workstation that has monitors of real-time data from the acoustic equipment.
Dr. Boswell with the main acoustic gear during assembly prior to the cruise.
Post by Drew Mertzlufft
My name is Drew Mertzlufft and I am pursuing a Masters degree in marine biology in the Oceanic Ecology lab at Nova Southeastern University (NSU) under the guidance of Dr. Tracey Sutton. The main goal of my thesis project is to describe the diet and ecology of pelagic juvenile scorpionfishes (suborder: Scorpaenoidei) from the Gulf of Mexico (GoM). In addition, I am creating a taxonomic key to aid in the future identification of Atlantic pelagic juvenile scorpaenoids. While the taxonomy, diet, ecology, and life history of adult scorpionfishes in the GoM are well documented, the identification methods, diet, and food web relationships of juvenile scorpionfish remain largely unresolved.
Drew in action (Photo: H. Judkins)
Aside from my thesis, this is my first time out to sea on a research vessel. I must admit that it has been an extremely humbling experience thus far. I am very fortunate to be surrounded by an extremely considerate and compassionate team of highly distinguished scientists as well as the incredibly proficient and friendly crew. All of which have been helping me use the scientific method to figure out how to remedy sea sickness. Not to mention the chance to see and work with fishes that most people go their entire lives without knowing of their existence! I am very grateful to be able to assist with the collection and processing of all fishes captured during the seventh DEEPEND expedition as well as helping update the Cruise Track.
Some of my favorite animals so far:
Deep sea amphipod (Phronima) Photo: DM Lanternfish (Myctophid species) Photo: DM
Cookie Cutter Shark (Isistius brasiliensis) Photo: DM
Post by Daniella Milanese
My name is Daniella Milanese and I am a graduate student in Dr. Tamara Frank’s deep-sea biology lab at Nova Southeastern University. I am currently working on my master’s thesis on “Plastic Ingestion of Deep-sea Pelagic and Benthic Decapods of the Charlie Gibbs Fracture Zone at the Mid-Atlantic Ridge”. For my thesis, I’ve extracted plastic particles out of pelagic and benthic crustaceans before I find out if ingestion differs by region of the fracture zone.
Photo: Daniella and Tammy Frank (Photo: H. Judkins)
Besides my research, this is my first DEEPEND cruise and I am beyond excited to be part of such a wonderful team that works together to survey the Gulf’s deep-water ecosystem. Being in Dr. Frank’s lab, I have worked with majority of the decapod species captured in the Gulf, but to work with fresh specimens is a brand new experience! Being able to see true coloration and pristine photophores is truly a treat and a wonder to see. On this DEEPEND expedition, it’s my job to help identify and process all decapods captured.
Photo: Deep Sea Shrimp (Photo: DM) Photo: Deep Sea Shrimp (Photo: DM)
Photo: Fangtooth (Anoplogaster cornuta) (Photo: DM)
We left the dock on the R/V Point Sur at midnight and reached our first station in the Gulf of Mexico around 2 pm today. All supplies, microscopes and equipment got set up and stored away in the dry lab and we settled in for the welcome and safety meeting. The great news is that since we followed the LUMCON Covid-19 protocols including quarantine, and we are vaccinated, the team is ready work!
Today has been spent putting the MOCNESS together. This is a Multiple Opening and Closing Net and Environmental Sensing System that we use to collect a variety of organisms from various depths in the midwater column (MOC10). We will be dropping the 6-net system to 1500 m and collecting animals at different depths as it comes back to the surface. Part of the team is testing and calibrating the acoustics array which will collect data using sound waves throughout the cruise. The CTD (measures conductivity, temperature, and depth) has been set up as well which will be deployed to collect water quality data. Our DEEPEND photographer is spending the day setting up his lab as well. Things are coming together quite nicely so far.
We are excited to be out here and ready to do some science!
The time has come! Our first NOAA RESTORE cruise efforts are underway. Strategically packing the van for the trip is the true test for the team. All the nets, acoustic equipment, microscopes, field guides and supplies are loaded into a van under the watchful eye of April Cook, our amazing program manager at Nova Southeastern University. Every year, it seems like a miracle that everything fits but it always does! It takes approximately 12 hours to make the journey through Florida, Alabama, and into Mississippi. Other team members drive cars/SUVs with their own gear and everyone arrives in Gulfport, MS tonight so we are ready bright and early tomorrow morning to load the gear onto the R/V Point Sur. Tomorrow will be a day of setting up the dry lab, storing supplies, putting the MOC10 net together, and attaching the acoustics equipment to the vessel so we can leave at midnight.
We are excited to get underway and will update you in the next day or two!
(Photos: Ashley Marranzino)
After an odd year dealing with the pandemic, which resulted in one postponed research cruise, the DEEPEND team is gearing up for our first NOAA/RESTORE cruise later this month! We are excited that we received funding through 2024 to continue our important midwater survey and associated projects. We have a series of three cruises planned, with the first one going out on April 24th, 2021. We will be exploring the northern Gulf of Mexico using a midwater trawl and acoustic equipment to identify long-term trends in pelagic fish, shrimp, and squid abundance, and determine how observed trends relate to environmental changes and human pressure (e.g., pollution). The ultimate goal of the project is to provide information that can be used by resource managers to protect the natural resources of the Gulf.
The team will be leaving from Gulfport, MS, on the R/V Point Sur for 12 days and we are ready to get to work! As in the past, we will have a shiptracker and a HYCOM oceanographic model running in real time to help guide our voyage. We will also maintain a blog to document the various projects and discoveries throughout our journey. These are all accessible on the home page of the DEEPEND website: www.deependconsortium.org
If you want to read more about NOAA/RESTORE Science program, here is the link: https://restoreactscienceprogram.noaa.gov/
Looking forward to sharing our experience with you!
Join DEEPEND at Rock The Ocean’s Tortuga Music Festival in Conservation Village as we find ways to #RockTheOcean in 2019!
When: April 12-14, 2019
Where: Fort Lauderdale Beach, in the Conservation Village
What: The DEEPEND Booth will have deep-sea trivia, guessing games, and a photo booth this year! You can win glow in the dark anglerfish tattoos or a DEEPEND t-shirt! Come visit our booth while enjoying the sights and sounds of the festival!
As a nominee for ACM Festival of the Year, saving the oceans and shifting to more sustainable habits is something we all want to do, but where do we start? This question can be daunting when wanting to make lifestyle changes to help our oceans. It’s nice to have a little education on how you can make a difference! This is what Conservation Village at Rock The Ocean’s Tortuga Music Festival is all about – educating fans on conservation initiatives, lifestyle changes, and raising awareness for the protection of our oceans. We will be joining 30+ other leaders in ocean conservation to deliver simple, unique ways fans can help save our oceans.
Tortuga Music Festival has grown over the past seven years to become one of the largest music festivals in the world. With this growth, the conservation efforts have grown as well. A few of the on-site efforts this year will include:
- Minimizing Waste and Reducing Single Use Plastics:
- Festival Wide recycling
- Food vendors using only compostable serviceware
- Provide free water refill stations. Fans will be encouraged to bring and use their own refillable water bottles.
- No plastic water bottles. Fans can refill their water bottles at a water refill station or Open Water in aluminum cans will be available for purchase.
- No plastic straws. We have a straw by request only policy, substituting plastic straws with ocean friendly paper straws.
- Donation of all leftover food.
- New in 2019: Reduce single-use plastic by purchasing a limited Tortuga Music Festival Pint Cup! Purchase one with your first drink and use it all weekend long!
- Supporting Sustainable Food Systems:
- Tortuga is committed to only serving sustainable seafood. This means that any seafood item served at the festival must be caught or farmed in environmentally responsible ways. Vendors must source seafood that is listed as a “Best Choice” or “Good Alternative” by The Monterey Bay Aquarium Seafood Watch program.
- Additionally, we are committed to only serving meats raised without the use of antibiotics and produce that has been sourced from within 200 miles of the festival site. This is in order to support the local community and promote positive animal welfare practices.
- Encouraging Alternative Transportation:
- Fans will be encouraged to take advantage of alternative transportation options that reduce the emissions associated with fan travel to and from the festival. Alternatives include:
▪ Water Taxis
If you or someone you know will be at this year’s Tortuga Music Festival, come see us and learn how you can help #RockTheOcean!
The Deep-Sea Biology Symposium is an international scientific gathering and I was privileged and honored to have been able to attend the 15th such symposium in Monterey, California, thanks to two travel awards. The first was sponsored by FAU’s Environmental Sciences Program for winning Best Student Poster at the annual retreat in 2018. The second was an award from the DEEPEND Consortium through funds donated to them by Rock the Ocean Foundation for participating in the Tortuga Music Festival’s Conservation Village. Of course, the session topics at this deep-sea conference were utterly fascinating. Even though I have been a graduate student with DEEPEND for three years now it really felt like I was being told about the deep ocean for the first time. It was simply a thrill to spend a week learning about the biology of hydrothermal vents, hadal zone fishes, bioluminescence, cold-water coral reefs, bizarre and intriguing invertebrates like giant larvaceans and tomopterid worms, and that the blackest color black imaginable is on the skin of a fish! Mind blown. But the science and the scientists really impressed me the most. The quality and caliber of science coming from these researchers, who hail from all over the world, is breath-taking. What's more: almost all of these folks knew each other as old friends! A global community of deep-sea researchers, pushing the boundaries of knowledge on what is truly one of the last frontiers of human exploration, are actually all old drinking buddies! As for myself, I quickly found a large and warm group of fellow grad students and post-doc researchers, themselves from all parts of the globe, with which to explore Monterey. Monterey is a gorgeous place and I truly believe the Bay, the Aquarium and the Research Institute there are national treasures. I made many new friends and traded business cards and kind words with fellow students and veteran researchers alike, sharing our love of ocean life with geek-like enthusiasm. However, we also learned a great deal just how much is at stake for our beloved oceans. Whether it be oil spills, deep-sea mining, plastic pollution, over-fishing, or global warming, there are innumerable perils humankind has wrought on the oceans. Between this call to arms, the beauty and awe of the science, and the comradery of the community, I have never been so inspired to remain in academia and contribute to a scientific field than I was by this symposium. With no small amount of effort, and a whole lot of luck, I hope to attend the next symposium in Japan to see my new friends again and to share in their discoveries while working to keep our oceans healthy and diverse well into the future.
We are in the home stretch for this DEEPEND cruise with only one trawl left to process on our last day out here at sea. This cruise has been just as productive as every other trip we have conducted with lots of hard work, long hours, and rewarding finds! Here are some fun facts from our six cruises out here in the Gulf of Mexico:
We have found great diversity of species for the major taxa: 61 cephalopod species, 120 crustacean species and 627 fish species! These are important numbers as in the past the midwater habitat was not considered a particularly diverse region.
Here are the winners for the most abundant animal in each category:
Most abundant fish: Cyclothone sp.
Most abundant crustacean: Euphausiids
Most abundant cephalopod: Pterygioteuthis sp. (P. gemmata and P.giardi)
With regards to operations, here’s what we know:
Number of miles traveled: ~6496 miles on the R/V Point Sur out here in the big blue!
Total number of MOC trawls successfully deployed and retrieved: 122
Total number of hours the MOC was in the water: 671 hours
We have 1764 hours of acoustics data collected.
We have ~40,000 species and team photos from Dante Fenolio’s efforts.
Photo: Acoustics attached to the MOC for deployment
What have we found so far? We have found five cephalopod species and more than 20 species of fish that are new to science (descriptions are in the works) and we have approximately 180 fish species that are new records for the Gulf. We have found that each time out here, we have been surprised about how changeable the water conditions have been as we go down the water column- from moving across eddy features to observing and documenting the outward flow of the Mississippi River. We have found that hard work is exhausting but absolutely rewarding as we have so much science to share with all that we have found so far! We have been able to support more than 30 students, research technicians, and post docs through the DEEPEND program to date. This has been essential to maintaining our productivity for the last four years.
So, how has all of this amazing science been possible? We give a HUGE thank you to NOAA/NRDA and GoMRI for this opportunity to explore this unknown region of the Gulf. We now have eight years of continuous data in the same region, using the same methods which allows us to explore connections, gaps, and patterns that occur within and between these depth layers.
We also thank Captain Nic and the crew of the R/V Point Sur for their tireless work to keep our science moving each and every cruise. We wouldn’t have any science to share without you guys along the way! Thank you!
Each DEEPEND team member wants to thank their home institutions for their support for this effort over the last four years. These cruises have an extremely surprising and enlightening endeavor and we have lots more science to report on from these efforts. We expect to have research output and publications continuing for at least the next ten years. Where would we be without Matt Johnston, our data manger and land connection while on our cruises? Thanks to him for all his efforts! April Cook, our rockstar project manager has kept us all in line for the last four years and continues to do so, thank you! And, we can’t go without thanking our amazing director, Tracey Sutton- his work ethic combined with humor has allowed us all to grow as a team over the years, thanks, Tracey!!
Photos: April and Tracey sorting a sample; Tracey with a Mahi
Keep checking in on us for more news, publications, and highlights from the DEEPEND science team as we continue to “fish for answers”…. Until we sail again!
My name is Nina Pruzinsky. I am a graduate research assistant in Dr. Tracey Sutton’s Oceanic Ecology Lab at Nova Southeastern University. I defended my master’s thesis on the “Identification and spatiotemporal dynamics of tuna (Family: Scombridae; Tribe: Thunnini) early life stages in the oceanic Gulf of Mexico” in May and will continue working in Dr. Sutton’s lab post-graduation. In my thesis, I determined characteristics that differentiate juvenile tuna species, which have been previously poorly described, and then mapped the distributions of the most abundant species (little tunny, blackfin tuna, frigate tuna, and skipjack tuna) collected in the Gulf of Mexico from 2010-2011 and 2015-2017.
Photo: Nina with a juvenile little tunny
With that being said, this is my first DEEPEND cruise! I am ecstatic to be a part of the team that is out surveying the Gulf’s deep pelagic ecosystem. I have worked with these specimens in the lab for the past two and a half years, and it is incredible to see the specimens when they first come up in the nets! The different coloration patterns and photophores of these deep-sea fish are amazing to see! On this DEEPEND cruise, I am working as the database manager and work alongside Natalie Slayden. Our job is to back process the fish specimens identified by taxonomists Drs. Tracey Sutton and Jon Moore. Check out Natalie’s blog below to learn more about our jobs at sea.
In regards to my research, I am continuing to sample the larval and juvenile tuna in the Gulf of Mexico. Scombrid counts on this cruise exceed all other DEEPEND cruises thus far! On this cruise, we have collected various scombrid species and life stages. The majority of our catch has consisted of larval and juvenile little tunny. Due to the collaboration with C-Image III, we have also fished/caught adult tunas as well. As Heather mentioned, we are collected tissue samples of these adults for C-Image III and for stable isotope analyses conducted by Travis Richards.
Photo: Mixed larval tuna species (mostly little tunny)
We have collected larval and juvenile frigate and bullet tuna. At the juvenile stage, these two species cannot be differentiated; thus, we are running genetic analyses to determine which species this specimen is (see picture below). Additionally, we found a skipjack tuna in the stomach of one of the adult little tunny that Max Weber caught on the cruise! The MOCNESS also collected a larval skipjack as well. We also caught an adult bonito, and Gray Lawson, our MOCNESS operator, caught an adult yellowfin tuna. It is exciting to see the diversity of tuna species collected this trip!
Photos: Max and Nina with a little tunny; Bottom photo: Gray with a yellowfin tuna
As I spent the majority of my thesis surveying larval and juvenile tunas, this cruise was the first time I saw adult tunas. We had several schools circling the boat, which was very exciting!! Hoping for more tuna sightings and catches as the cruise continues! J
The DEEPEND program has provided the opportunities for collaboration in so many areas over the last four years! In the education and outreach arena, we have been working with the Oregon Coast Aquarium (http://aquarium.org/education/oceanscape-network/) who highlights DEEPEND work and created our DEEPEND Vertical Distribution poster. This collaboration was made possible by one of our EO team members, Ruth Musgrave, who oversees our K-6 education components. We have worked with middle and high school teachers from Florida to Texas through our Teacher-At-Sea program and have remained in contact with many of them years after their at-sea experiences. We have also collaborated through community efforts such as the St. Petersburg Science Festival where both DEEEPEND and C-Image consortia shared space to enlighten children and adults about our offshore projects through interactive games and question and answer sessions.
Photos: DEEPEND Vertical Migration Poster and 2) C-IMAGE II and DEEPEND teams at the St. Petersburg Science Festival
Throughout the four years, our research efforts have also expanded outside of our consortium and other GoMRI groups. For example, in my case, I have been collaborating with other cephalopod researchers around the world about things we are discovering here in the GoM. From new species descriptions to future publications, I have truly benefitted from the DEEPEND work we have conducted to date!
One exciting new collaboration is the alignment of DEEPEND and C-Image III (http://www.marine.usf.edu/c-image/) consortia to tackle an existing gap in the offshore datasets we’ve been collecting. If you look to the DEEPEND shiptracker on our website, you will see the stations we are visiting for our MOC10 sampling work. What is great is that on August 10th, the C-IMAGE III team will head out to the same stations we’ve visited to conduct their longlining project. A total of 36 pelagic longline sets will be made with two gear sets per station (one during daylight and a second at night). This add-on longline survey will evaluate the abundance, food habits, and population demography of the predators, to take tissue samples for toxicology studies, and to evaluate the stomach fullness, species composition and to obtain genetic samples of prey items.
Photo: C_IMAGE III Director, Steve Murwawski catching a Red Snapper on a previous C-IMAGE cruise
Basically, C-IMAGE III will be collecting stomachs for a subsest of our consortia teams to examine to attempt to fill the gap of knowledge between our deep-sea organisms and their large pelagic fishes. What is the gap? Food web connections are difficult as there are many, many variables involved with who eats whom, when does everybody eat, at what depth are they eating, etc. If we can connect the DEEPEND organisms with these more shallow top predators, we will gain a better sense of the energy transfer that occurs between these two groups. We will be working with this new project when everyone is back on land and in the labs!
Assessing marine ecosystems health requires multiple tools to study in an integrative way environmental pollution and impacts across different biological levels. One of the main challenges is to link physical, chemical and biological components in large-scale ecosystems when little information is available. For example, the Deepwater Horizon oil spill in 2010, contaminated the water column in the Gulf of Mexico from the epipelagic (0-200 m) to the mesopelagic (200 -1000) and bathypelagic (>1000 m) habitats; but assessment of the impact to the deep-pelagic GoM was hampered due to a lack of comprehensive data regarding diversity, abundance, distribution, and pollutants baseline-content of pelagic fauna. Several programs since the spill (e.g. DEEPEND Consortium) have improved our knowledge and understanding of the deep-pelagic ecosystem, the largest habitat in the Gulf of Mexico, and on Earth. However, information regarding the source, composition and inputs of chemical contaminants to deep pelagic fauna is still absent. Chemical contaminants can alter biological diversity and ecosystem functioning, therefore are key for linking long-term population dynamics and environmental stressors.
As part of the DEEPEND Consortium, my role is to establish a time series of chemical composition in deep-pelagic fauna (fishes, shrimps, cephalopods) collected after the Deepwater Horizon spill. For this study, the analysis of polycyclic aromatic hydrocarbons (PAHs) was chosen because: 1) these compounds are common in crude oil; 2) are persistent in the environment; 3) their composition can be used to broadly detect the source of contamination; and 4) can be toxic to fauna. PAHs are a large group of organic compounds organized in multiple aromatic rings typically found as complex mixtures. They are present in petroleum, coal, wood, and their combustion products. When present in high amounts, for example after an oil spill in the ocean, PAHs can cause lethal and sub-lethal effects on fauna like juvenile and adult fishes, potentially increasing mortality, skeletal malformations, genetic damage, immunotoxicity, etc.
Recently, with the collaboration of different programs, we were able to establish a decadal assessment of PAHs in mesopelagic fish tissues as indicators of environmental contamination in the deep-pelagic ecosystem. The results generated from this study indicate deep-pelagic fishes were exposed to elevated concentrations of PAHs after the Deepwater Horizon spill (2010-2011). In 2015-2016, PAH concentrations were close to the levels measured in 2007; but only for muscle tissues, because elevated concentrations were found in ovaries containing eggs. The high concentrations of PAHs found in 2010-2011 (muscle tissue), and 2015-2016 (eggs) are within the range of PAH concentrations found to cause lethal and sublethal effects on fishes. These results suggest a long-term sink for oil in deep pelagic organisms, potentially greater than shallower counterparts. Our findings demonstrate the importance of monitoring the persistence of organic contaminants in deep pelagic organisms. However, our study also indicates the need for more extensive ecosystem-based efforts of the deep-pelagic ocean (> 10 years) to better understand the long-term impacts across multiple levels of biological organization.
Here are some of the animals I am examining for PAH contamination:
1) Cyclothone obscura; 2) Onychoteuthis banksii,; 3) Histioteuthis corona
For DEEPEND, I am one of the taxonomists that identify the cephalopods (squid and octopus) that are collected from the MOCNESS nets. I am also collecting two other mollusc groups, pteropods (Sea Butterflies) and heteropods (Sea Elephants). Once animals are identified, tissue could go to one or more of the following places for further DEEPEND study: Stable isotope analysis (examples food web interactions among fauna), PAH (studying possible contaminants), or genetic barcoding for species identification verification and genetic diversity analysis.
Photo 1: A Sea Elephant, Carinaria sp.
Photo 2: A sample of Sea Butterflies (pteropods)
One of the advantages of using the MOCNESS is that we can collect organisms at discreet depths to analyze patterns on a fine scale. All focus animals: fishes, crustaceans, gelatinous organisms, and cephalopods are examined to piece together a more complete picture of the midwater column dynamics as they all contribute to the carbon moving from the surface waters to the deep-sea floor.
Team Mollusca are looking at vertical migration patterns for our three groups. Past studies on cephalopod vertical migration involve very few individuals per species so it is important to make the most of the large collection we have to further analyze these patterns. Our findings suggest that there is no one set vertical migration pattern by group but the patterns differ by species. For example, deep-sea pelagic octopods and the Vampire Squid are not found above 600m in the water column while the Moon Squid and Firefly squid move from the mesopelagic (200-1000m) to the epipelagic (0-200m) nightly, presumably for feeding purposes. We are noticing similar patterns in the heteropods, some migrate upwards and some do not. Pteropod analysis is underway at this time, stay tuned!
Here are some of the molluscs that are migrators and non-migrators,
Non-migrators: Japetella diaphana and Vampyroteuthis infernalis
Migrators: Selenoteuthis scintallins and Pterygioteuthis sp.
In the DEEPEND, we apply many techniques to learn about the animals that live in the depths of the twilight zone. One of the types of equipment we use is called an echosounder. While this may sound like a strange instrument, its actually quite common and in fact is on most fishing boats, and often called the ‘fish finder’ or the ‘bottom machine’. We use a similar type of fish finder that is powerful enough to send and receive sound to the depths of the ocean and use the data we collect to study the patterns of the animals in the deep scattering layers (DSLs). In the figure, the daily migration event can be seen with many of the animals within the DSL moving from the depths into the surface at night. Interestingly, not all animals move up at night and some remain at depth and the use of the acoustic devices helps us to better understand how the DSLs change in space and time.
Photo 1: Output from the echosounder of the DSL layer moving up at dusk
Photo 2: Examples of collected animals in the MOCNESS that the echospunder attempts to pick up. Interestingly, squid and octopods don't create a strong enough signal for the echosounder to pick up.
While the echosounder provides important data about the timing, extent and intensity of the migration patterns and the DSL in general, acoustics are limited in their ability to discriminate among species. Because of this limitation, we use net to collect samples to identify the community of organisms which also permits us to describe the diversity of species that we encounter. The mesopelagic community in the Gulf of Mexico is hyperdiverse with greater than 800 species of fishes, crustaceans and other invertebrates.
Indeed, the most prominent piece of equipment that we rely on is the MOCNESS which allows us to collect specimens at through the water column.
The echosounders on the ship provide a picture of large patterns in the ocean so we can learn about the processes that are important at broad scales. However, it is often useful to be able to zoom into the layers and see the individuals that live in those deep areas and to look at them one-on-one. To achieve this, we have attached an autonomous battery-powered echosounder onto the frame of the MOCNESS and added two transducers that collect acoustic data very close to the individuals (~20-40m). By placing the echosounder closer to the animals at depth, we can actually count and measure individuals and learn about their behavior in the dark without the need for any lights. We are learning a tremendous amount from the data we have collected on these animals and are excited to see what tonight’s sampling event shows us!!
Photo: Echosounder attached to the MOCNESS and output screen of individual animals
Hi! My name is Natalie Slayden, and I am a Master’s student at Nova Southeastern University working as a Research Assistant in Dr. Tracey Sutton’s Oceanic Ecology Lab. This DEEPEND cruise is my first research cruise!
Photo: Natalie and Nina prepping the MOC
On this DEEPEND cruise, I am a part of the fish processing team. The process begins with the boat pulling the MOCNESS which is a net system consisting of six nets. One net fishes open the entire time, while the other five nets open and close at different depths allowing us to determine where we catch certain species by depth in the water column. Once the nets are pulled out of the water, the fishes are brought into the lab per net. Dr. Tracey Sutton sorts and identifies each fish to species. I then weigh, measure, and preserve the fishes based on how they will be utilized. All this information is entered into the DEEPEND database by my partner in crime, Nina Pruzinski. Several universities use these fishes for varying projects.
For my thesis project, I am looking at the otoliths (ear stones) of non-vertically migrating deep-pelagic fishes to determine their age. I will also describe the otolith patterns and correlate those patterns to the life history of the fishes. Fishes have otoliths to help them orient themselves within the water column and detect sound. The otoliths have rings that can be counted to determine age. The rings can represent days, months, years, or a single meal. The fishes I will use for my project are frozen so that I can remove and analyze the otoliths once I get back to the lab at Nova Southeastern University. Below are some pictures of the fishes that I will be using for my age and growth study!
Photo 1: Nannobranchium lineatum (Lanternfish species)
Photo 2: Chauliodus sloani (Viperfish species)
On DEEPEND cruises we spend most of our time doing science-related activities that you may have read about in previous blogs. Believe it or not, we do occasionally have down time and we have to figure out how to fill it. There is a TV in the galley that is quite popular to hang around and watch during meal times and late at night. My favorite DEEPEND pastime however, is fishing!
Photo: Max on the hunt for his first tuna
DEEPEND researchers assemble a stack of rods and reels before every cruise in the hopes we will stumble across some good fishing action. This is not guaranteed and I have been skunked on previous DEEPEND cruises. On afternoons when the net is not in the water and we are in transit to another station trolling is the go-to method of fishing. We have already landed on small tuna on this cruise while trolling.
Photo: The rod and reel assemblage area of the lab
Typically the best fishing takes place when a school of fish or some sort of floating structure (like sargassum or floating boards) is spotted. Floating structure often attract small baitfish, which in turn attract larger predators. Already this cruise we have stumbled across a school of Chicken (small) Mahi and Little Tunny. I have landed two Mahi and a Little Tunny, which was my first ever tuna species caught on a rod and reel!
Phptps: Ocean Triggerfish; Travis with a Little Tunny; Bpttom photo: Little Tunny
Photo: Laura on a DEEPEND cruise
I went on the very first DEEPEND cruise. I was in the second year of my PhD and I couldn’t believe my advisor, Dr. Heather Bracken-Grissom, was sending me to initialize collection protocols for the crustacean genetics portion of the proposed research. Because research cruises are the best (only) means of collecting our target specimens, they are very important. Moreover, every cruise is an opportunity to collect for multiple projects. When I went out that first time, I was collecting for five or six research projects…it was a lot of pressure.
Since then, the DEEPEND cruises have been a staple of my graduate school career. I’ve been on five of the six cruises. It’s difficult to describe what these cruises are like: a flurry of collection activity, a sleep-deprived science bender, a two-week oceanic boot camp. They are challenging and rewarding and they shape what sorts of questions DEEPEND can ask and address. Over the course of these cruises, I’ve collected thousands of specimens and used them to illuminate the connections between the midwater Gulf and the Atlantic.
Last month, I successfully defended my doctoral dissertation. In the days preceding the event, many DEEPEND scientists reached out to wish me luck. And along with all the concrete, quantifiable benefits of these research cruises, these communications emphasized again the myriad qualitative benefits: I’m a better scientist for having been a part of DEEPEND. On that first cruise I was a slightly under-prepared, over-eager graduate student on a ship full of experienced researchers and scientists who immediately supported and accepted me as one of them. They encouraged me and offered me a place at their table. The collaborations and relationships established on these cruises will last my entire professional career.
One month before this cruise left dock, I accepted an NIH postdoctoral fellowship at the University of Colorado. One month after we return to dock, I’ll move to Denver and take up the position in the Computational Biosciences Department. The talk I gave during the application process was comprised entirely of my work with DEEPEND – a talk refined through rehearsals with DEEPEND scientists and GOMOSES presentations.
This post is getting a little longer than I intended, so I’ll end it the way I end most cruises: with gratitude. GOMRI, DEEPEND, FIU, R/V Point Sur, Dr. Bracken-Grissom, thank you. Thank you for letting me roll with you.
Photos: Laura hard at work during DEEPEND cruises. So many crustaceans to identify and sample!
When the nets come up, it’s time to sort…. Each net is processed one net time so we don’t mix up samples between one net and another. The entire process can take anywhere from four to six hours depending on how full each cod end is. We first identify the organisms and then they go to Nina and Natalie for data entry. Animals are being used for multiple studies once we are back on our labs: DNA barcoding, genetic diversity studies, stable isotope analysis, contaminant analysis and vertical distribution studies.
Here is just a sample of some unique specimens we’ve collected so far!
Photo 1: Nina and Natalie at the data entry station
Photo 2: A sample of the over 600 euphausiids (krill) that team crusty had the pleasure of counting from one net
Photo 3: A selection of bristlemouths and a hatchetfish that was going to processing for the PAH study
Photo 4: Nina with a Fangtooth fish
Photo 5: The mollusca collected on one of the tows- 4 small pelagic snails, one small Vampire squid and a Chiroteuthis mega (deep-sea squid)