Author: Hannes Baumann

Bridget Holohan – MVP technician

By Ewaldo Leitao

Easy and hard to find – her door is always open but without a name tag – ready to help, and to give advice (for 5 cents), Bridget Holohan has been in the marine sciences community for over two decades. Bridget is currently working for two labs helping in many projects. Bridget is always ready with a sharp, witty joke, which is always appreciated and welcomed. Bridget kindly agreed to be interviewed and to tell us more about her path and career.

Bridget Holohan at the Avery Point campus

Ewaldo: What was your academic journey before you got here?

Bridget: I grew up in Michigan, and I wanted to be an oceanographer. The only school close to where I grew up that had an oceanography program was the University of Michigan, and I wasn't quite ready to go across the country at 18. When I was finishing up there –this was before the internet so finding a job to apply for was harder than it is now–I didn't quite know what I was going to do for a job and decided to go to graduate school. Okay, maybe it wasn’t the best decision to go based on that. I went to the University of Rhode Island and got my master's degree. I thought about whether I wanted my PhD, but I decided that I like to be the one getting my hands dirty, not the one writing a proposal or writing the paper. I wanted to be the one doing it. So, I decided if I got a PhD, more than likely, that wouldn't be what I was doing. I stopped at a master’s degree, which was a good decision for me. As I was finishing up there, I saw a job in the state of Connecticut at the Williams Mystic program. They were looking for a TA.

Ewaldo: And how did you decide to be an oceanographer?

Bridget: I decided to become an oceanographer when I was the age of 12. My family went on a cruise down in the Caribbean and one of the things we did was snorkel. The first time I went snorkeling, I was blown away. I had no idea that there were all these amazing things under the surface of the water. No idea. I grew up in the Midwest. I knew about fish, we have the Great Lakes, but the organisms under the water in the Great Lakes do not look like in the tropics. It was just so incredibly fascinating. I wanted to study the ocean but at that point it was just a fantasy doing research on the ocean. I was planning to become a pharmacist because that seemed more sensible. However, when I started thinking about applying to colleges, I asked myself: why would I be a pharmacist? What I really want to do is oceanography.

Ewaldo: Williams-Mystic program. What is it?

Bridget: It's an off-campus study program of Williams College, which is conducted at Mystic Seaport. And it's entirely based around the ocean. Students come in for one semester. It's like a semester abroad, only it is a domestic program which is focused on the ocean. And they take either marine biology or oceanography. They also take maritime history, marine literature, and marine policy. They read Moby Dick, as you might imagine. They totally get immersed in the program.

Bridget and Evan Ward placing a chamber over coral to collect TEP in Bermuda

Ewaldo: That’s super interesting. What was your master’s degree in?

Bridget: My master's research was on the ecology of Ceriantheopsis americanus, which is a burrowing mud anemone.

Ewaldo: And why didn't you follow up on that particular topic?

Bridget: There's not a lot of jobs for that particular topic. So, I found a job that was mainly education. But it was a horrible salary. Like a third of what you students make. So, in the summer, I went to an oceanography summer camp and worked there. Then after a couple of years, I was like: “Okay, I cannot make a living at this”. I was searching around not being so successful. In the meantime, I did another environmental education job down in Virginia, which was fun.

Ewaldo: All the way down! So when did you come back up to the Northeast?

Bridget: As I was finishing that up, my former boss said: “I got a Pew Foundation Grant, and I put in money for a research assistant. Do you want to come work with me?” I said yes and I went to work with him, but it was only a two-year grant. As that was coming to an end, I saw a job by a man named Evan Ward. I didn't really know anything about culturing phytoplankton, which was what he wanted. But I figured I could learn. Why not? Right. So yeah, that's how I got here. And that was in 1999.

Ewaldo: It's been 24 years! And what was your position then – and currently?

Bridget: I was a research assistant when I started. Now, I'm a research assistant three, but in a lot of ways, my job is very similar. The only thing that has really changed is that as funding got tight, I started to work for Rob Mason as well. I also worked with Claudia for some time, because her job was expanding. I like the fact that there's a lot of variety. I hate being bored.

Ewaldo: You have done a lot of different things and learned a lot of things in this dynamic way. What were your biggest challenges and also biggest joys here?

Bridget: You know, I really enjoy working with bivalves, I like running experiments. Even though sometimes they can be a little crazy. I like seeing the whole process, from what we are proposing to do, to making it happen, and analyzing the data. And then luckily, I don't have to write it.

Ewaldo: Would you have advice for grad students?

Bridget: Boy, that's a really good question. One of the things in this is just kind of funny, because writing is not my favorite thing to do. But people often get hung up on the writing portion, thinking to themselves: “Okay, I need to write the perfect sentence”. Sometimes you just need to write. The beauty of the computer is that you can delete it, you can move it, you can copy and paste it into a different document. So you just have to get your ideas down on “paper”, and then refine them later. Just write it down, get it on the computer, and then fix it.
Also, I recognize that there can be a weird power dynamic between students and professors. But with most professors, you can really just say, “I need help with this….” Rather than wasting a bunch of time, being afraid to ask. Professors will be more receptive than if you wait five months and say you haven't been able to get this to work for five months. That is especially true when students are first starting out, and I see that is an easy role for me to fill. Because students are more comfortable coming to me and saying: “Hey, I don't know what's going on here”. Usually I can point them in a direction or even facilitate the conversation. And of course, there have certainly been times that my advice has been about things having nothing to do with oceanography.

Ewaldo: This is all great advice. Thank you. Maybe the final question, what's the story behind the five cents for advice in your door?

Bridget: I came back to my office one day, and we had a new nameplate and my title was wrong. Nobody told us they were going to change nameplates. I was not happy, so I took it off. I, of course, calmed down. I was going to put the correct title and make it more legible by making our names bigger (I shared an office at the time). It wasn’t a priority for me, so I took my time replacing it. One day I came back to my office and the Lucy character from the Peanuts comic was there. In the Peanuts comics, she had a little booth where she gave advice for five cents. One of my colleagues put it in there because sometimes people come to me for things other than science related advice. I found out later that it was Jeff Godfrey. I thought it was super funny, so I just left it. And one day I came back and there was a little bag of nickels.

Ewaldo: Who did that?

Bridget: It was Lydia Norton

Ewaldo: I guess that sounds about right! Hehe. Thank you so much, Bridget!

Graduated Master and PhD students 2022-23

The Department of Marine Sciences congratulates all our recent Master and PhD graduates! You worked hard, earned your degree, and enriched our community. Thank you, and best of luck for your next career steps!


Annalisa Mudahy (M.S. 2022)

Major advisor: Craig Tobias

Thesis: Spatial and Temporal Patterns of Water Column Respiration in an Urban Estuary Revealed Using Automated Respiration Chambers


Mathew Holmes-Hackerd (M.S. 2022)

Major advisor: Hans Dam

Thesis: Naupliar Exposure to Acute Warming Shows no Carryover Ontogenetic Effects on Respiration Rates, Body Size, and Development Time of the Copepod Acartia tonsa


Annette Carlson (M.S. 2022)

Major advisor: Samantha Siedlecki

Thesis: Quantifying Interannual Variability of Shelf Nutrients and Associated Hypoxia in St. Helena Bay with New Metrics and Tools


Lingjie Zhou (Ph.D. 2022)

Major advisor: Senjie Lin

Dissertation: Estimate Phytoplankton Carbon Biomass using DNA


Mary McGuinness (M.S. 2022)

Major advisor: Penny Vlahos

Thesis: Examination of Controlling Parameters for Total Alkalinity in Long Island Sound Embayments


Yipeng He (Ph.D. 2023)

Major advisor: Robert Mason

Dissertation: Air-Sea Exchange of Mercury and Its Species in the Coastal and Open Ocean


Patricia Myer (Ph.D. 2023)

Major advisor: Robert Mason

Dissertation: A Critical Examination of the Factors Controlling Methylmercury Uptake into Marine Plankton


Josie Mottram (M.S. 2023)

Major advisor: Julie Granger

Thesis: Refining the Use of Cold-Water Corals as a Proxy for the Marine Nitrogen Cycle Through the Comparison of the δ15N of Diet, Tissue, and Skeleton of Balanophyllia elegans


Michael Mathuri (Ph.D. 2023)

Major advisor: Julie Granger

Dissertation: Physiological Mechanism of Nitrogen Isotope Fractionation During Ammonium Assimilation by Marine Phytoplankton


CT-NERR is fully staffed and operational!

By Ewaldo Leitao

Thanks to the tremendous efforts of our esteemed researchers, the University of Connecticut now hosts the Connecticut National Estuary Research Reserve (NERR). The NERR System is a network of 30 coastal areas designed to protect and study estuarine ecosystems. The NERR System is a program of NOAA (National Oceanic and Atmospheric Administration), and recently Connecticut was added to this group. These reserves serve many purposes, and Long Island Sound is a large economic contributor and recreational area. Considering the importance of coastal and estuarine ecosystems, the Connecticut Reserve is an important program that fosters management guided through information collected by scientists. Some of the sites selected include Bluff Point and Haley Farm State Park. You can read more about it here.

While the initiative and leadership was spearheaded by Prof. Jamie Vaudrey within the Marine Sciences Department, the office now counts with many new names and faces. You will find them located in offices on the second floor. But we want to make sure to give them all a proper welcome! You can find their full bios and contact information here.

Jamie Vaudrey - Research Coordinator - CT NERR

Jamie is a marine ecosystems ecologist and modeler, interested in the impacts of humans on coastal waters. She received a B.A. in Biology with a minor in Philosophy from Wellesley College, MA; moved on to study environmental education in the Florida Keys, then in Oregon; then on to graduate school at the University of Connecticut. Jamie was the UConn lead, shepherding the establishment of a NOAA National Estuarine Research Reserve in Connecticut and is currently the Research Coordinator for the Reserve. Jamie is also involved with EPA’s National Estuary Program, serving on the science advisory committees of the Long Island Sound Study and the Narragansett Bay Estuary Program. You can learn more about her research interests by visiting her website: Her favorite reserve is the Mumford Cove! “I first ‘met’ Mumford Cove as a graduate student, 24 years ago – the study location of my dissertation. In 1999, eelgrass was just starting to recolonize the Cove and I had the opportunity to document the progress of its return, working with a team of fellow grad students and undergrads who are still some of my best friends today. Amazing how much a small Cove has to teach, and how many opportunities it provides!”

Larissa Graham - Education Coordinator - CT NERR

Larissa has worked in the environmental field for nearly 15 years, sharing science-based information with a variety of coastal audiences. She worked for the New York Sea Grant as the Long Island Sound Study Outreach Coordinator, and for the Mississippi-Alabama Sea Grant, the Grand Bay National Estuarine Research Reserve, and, most recently, the Student Conservation Association as the Alabama and Mississippi State Director. Larissa is looking forward to settling back into her New England roots. She spent a lot of time boating and fishing with her family as a child, which fostered her love for the Sound.

Ashley Hamilton - Research Assistant - System Wide Monitoring Program (SWMP)

Ashley graduated from the UConn Avery Point community with a B.S. in marine sciences, and completed a master’s degree from the University of Rhode Island, where her research focused on the impacts of anthropogenic stressors to commercially important bivalve species. Since 2016 she has worn various hats in the shellfish and seaweed aquaculture industry, including farm hand, hatchery production and researcher. Ashley is excited to guide the next generation of undergraduate researchers. Ashley shared that her “NERRdiest” thing is to get tattoos of the organisms she works or studies, which includes a (scientifically accurate!) anatomical eastern oyster. She shares: “Next on my wish list is a blue mussel shell in celebration of finishing my thesis, and I can see some marsh plants and critters in my future as I venture into the CT NERR monitoring program!”

Jason Krumholz - Stewardship Coordinator - CT NERR

Jason is an Associate Professor at UConn and the Stewardship Coordinator for the Reserve. In this role, he helps to facilitate resource inventory, conservation, and restoration goals in concert with federal, state, and local partner organizations as well as contributes to scientific research, outreach, and education efforts at the Reserve. He served with NOAA’s Northeast Fisheries Science Center as the Liaison Ecologist to the Long Island Sound Study, where he worked with a wide range of partner organizations at the interface of science and policy on several efforts to improve the transmission of scientific data into management. He is the Chief Scientist for two small non-profits; The Reef Ball Foundation, which uses designed artificial reef technology to facilitate coastal restoration, and Slow No Wake, which works on marine debris removal and education in the recreational fishing sector. He is also a founding board member of Remote Ecologist, a non-profit organization designed to remove the barriers to participation faced by independent and unaffiliated research scientists. Jason recounted that once he got roped into diving off of Pine Island to collect green crabs in the middle of the winter for a colleague. "It was so cold that ice was literally forming on our gear. It was one of those moments that was pretty miserable at the time, but the memory of it is somehow very positive… one of those moments where you realize that if you like what you do enough to do THIS, then you’re probably going to really enjoy doing it for the rest of your career.”

Katie Lund - Coastal Training Program Coordinator - CT NERR

Katie joins the Reserve from her previous position at UConn’s Connecticut Institute for Resilience and Climate Adaptation where she led engagement activities and managed municipal and research grant projects to increase resilience of Connecticut’s communities to the growing impacts of climate change. Katie has worked for over 20 years on a variety of coastal management topics – including the Northeast Regional Ocean Council and Long Island Sound’s marine spatial plan and the Massachusetts Office of Coastal Zone Management’s special area management. Katie holds an M.S. in Marine Resource Management from Oregon State University. “One of my favorite memories of the Reserve is the first walk I did on Bluff Point with my kids when they were very young”, shared Katie. “After we’d gone a couple miles and they were ready to turn around, I saw a small side trail to the right and convinced them to try it. We popped out onto a beautiful beach…such a surprise – I had no idea there was such a BIG and quiet and beautiful beach as part of Bluff Point. Over ten years later, I now work for the NERR and this beach is part of our new reserve!”

George McManus - Interim Manager and UConn Center Director - CT NERR

George is a biological oceanographer. He received his PhD from Stony Brook University and worked at the Cary Institute of Ecosystem Studies, the University of Maryland, and the Dauphin Island Sea Lab before coming to UConn, where he has taught for 28 years. His research is focused on microbial plankton, including bacteria, phytoplankton, and ciliated protozoa, documenting their diversity and distributions in the coastal ocean. He is currently serving as the Interim Reserve Manager and Center Director. One of his fond memories of the Sound is when he was fishing with his son and a seal popped up next to the boat with a fish in his mouth. “We just stood there watching and marveling at this bit of the food chain taking place before our eyes”, said George.

Sam Stadnick - Fiscal Officer - CT NERR

Sam joins the Reserve as its Fiscal Officer after working in the Connecticut House of Representatives where he assisted elected officials with their constituent service and legislative responsibilities. He is thrilled to use his experience in public affairs to protect the natural areas of Eastern Long Island Sound and the Lower Connecticut River Valley where he has been a longtime hiker and boater. Sam is also very proud to return to UConn, where he graduated with a B.A. in Political Science. Sam mentioned that: “When fishing near Millstone Point with my father, we would often catch Tautog, or blackfish – one of the most beautiful (and delicious) fin fish in Long Island Sound. The rocky outcroppings that lie off of Millstone Point provide great habitat for the fish and great recreational fishing opportunities.”

Jamie Vaudrey

Larissa Graham

Ashley Hamilton

Jason Krumholz

Katie Lund

George McManus

Sam Stadnick

Marine Science Day
Prof. Jamie Vaudrey and PhD Student Matthew Leason working with students at Marine-Science Day

Brittany Sprecher continues science in Germany and California

By Ewaldo Leitao

Brittany Sprecher finished her PhD in December, 2020, and soon after she moved to Germany to continue her investigations on phytoplankton molecular biology. In her PhD, Brittany was able to develop molecular techniques to begin to help explain the complexity of dinoflagellates. Dinoflagellates are small eukaryotic cells that can photosynthesize and produce their own energy or, sometimes and, be heterotrophic, eating even smaller cells such as bacteria. Their complexity does not end there. Their genomes are astoundingly large, varying from one third up to 90-fold that of the human genome size. This complexity translates into lots of unknowns on their molecular characterization, that Brittany has bravely shed some light on during her PhD.

Brittany performing experiments
Brittany performing experiments

Ewaldo: Thank you so much for agreeing to be interviewed. First, can you give me a brief explanation of your work conducted while in UConn?

Brittany: I had the great opportunity to work under Prof. Senjie Lin and Prof. Huan Zhang. My work primarily involved developing transformation methods for dinoflagellates, a complex group of organisms. Additionally, I utilized transcriptomics to gain insights into the molecular characteristics of a recently discovered dinoflagellate. It's fascinating how much we still have to learn about these organisms, as many of their genes remain unknown in terms of their functions. Even key pathways like toxins and bioluminescence, which have significant ecological importance, have missing or poorly understood genes. To address this knowledge gap, I focused on establishing a method to introduce foreign DNA, such as the green fluorescent protein or an antibiotic-resistant gene, into dinoflagellates with the goal that the cells would take up and express the introduced proteins.

Ewaldo: This is super interesting. So where did you go after your PhD? And how did the work at Uconn allow you to get there?

Brittany: After obtaining my PhD, I had the opportunity to do a Postdoc in Germany, which turned out to be an incredible experience. Interestingly, my focus remained on method development, but this time I shifted my attention to diatoms who are endosymbionts of dinoflagellates. The transformation methods for diatoms were comparatively more straightforward, allowing me to complete the method development in just one year, whereas it took four years for dinoflagellates. I believe that the valuable experiences and challenges I faced during my PhD greatly contributed to my success during the Postdoc. The obstacles we encounter along the way ultimately shape us into stronger scientists with enhanced troubleshooting abilities.

Ewaldo: This seems like a great experience, to do your Postdoc abroad.

Brittany: Absolutely! It was truly fascinating to observe the research and graduate school culture in Germany. One aspect that particularly stood out to me was the tradition of having lunch together as a lab. Initially, I found it a bit strange, feeling the urge to quickly return to work. However, I soon realized the immense value of these interactions. During these lunch sessions, we would engage in discussions about science, troubleshoot any issues we were facing, or simply delve into various aspects of life outside of work. This time proved to be exceptionally productive and nurturing for our mental well-being, fostering collaboration and support among lab members. The experience of sharing meals together truly enhanced our ability to collaborate and assist one another with our projects. On the whole, my time in Europe was an enriching experience that expanded my scientific network and broadened my perspective on research.

Ewaldo: Indeed. What are you up to these days?

Brittany: Currently, I have the privilege of working at the University of California, San Diego, on an NSF Postdoctoral Fellowship in Biology. I'm actually continuing one of the research chapters from my PhD, focusing on a dinoflagellate species that exhibits native green fluorescence. My project involves utilizing analytical chemistry techniques to determine the structure and potential function of this fluorescent molecule. While analytical chemistry is slightly outside my expertise, I am fortunate to be part of an institution that fosters collaboration, and I have been able to connect with several supportive chemists who are aiding me in this discovery. Additionally, I'm conducting laboratory experiments to identify the conditions under which the green fluorescence changes, and I'm collecting samples from the Scripps Pier to assess the prevalence of this blue-green fluorescence among dinoflagellates locally and hopefully globally by the end of this fellowship.

Extracted Dinoflagellate green
Extracted Dinoflagellate green fluorescence molecule Brittany is currently working on

Ewaldo: Incredible expertises. So what are your next steps? Do you have anything in mind?

Brittany: I'm deeply passionate about dinoflagellates and diatoms, and my aim is to continue delving into these fascinating organisms. Consequently, I will actively pursue academic positions that allow me to further explore and contribute to this field. Additionally, I plan to continue applying for fellowships and grants that can support my research endeavors. My ultimate goal is to make meaningful contributions to our understanding of these organisms and their ecological significance.

Ewaldo: Since you mentioned the struggles of a PhD student, do you have advice for grad students and / or early career?

Brittany: One of the most valuable pieces of advice I received before starting my PhD was to invest time in getting to know my cohort. I cannot stress enough how important this has been for me. The support, camaraderie, and collaboration that I have shared with my cohort has been invaluable in navigating the ups and downs of graduate school. Additionally, I highly encourage graduate students and early career scientists to actively seek out and apply for fellowships and grants. These opportunities not only provide financial support but also open doors for networking and collaborations. Lastly, remember that collaboration is key. Engage with your peers and colleagues, seek opportunities to collaborate, and leverage the collective knowledge and expertise around you. Together, we can accomplish so much more than we can individually.

Ewaldo: Finally, what are your hobbies?

Brittany: In my free time, I absolutely love surfing. Living in California provides me many opportunities to ride waves, and it's always a special experience when I find myself sharing the ocean with playful dolphins or witnessing the graceful dives of brown pelicans in search of food. I am also incredibly lucky to be reunited with Dr. Lingjie Zhou, who has been an incredible support in my life. It has been wonderful to spend time with her again both within the academic setting and in our personal lives.

Lingjie and Brittany
Lingjie and Brittany taking in the views near Lingjie’s SIO office

Brittany and Lingjie enjoying the views outside Hubbs Hall at UCSD
Brittany and Lingjie enjoying the views outside Hubbs Hall at UCSD

Finally in person again: Feng Graduate Research Colloquium 2023!

On 18 May 2023, Department of Marine Sciences graduate students and faculty came together for the 14th Biennial Feng Graduate Research Colloquium

18 May 2023. After a COVID-forced hiatus of more than two years, our department finally held a successful Feng graduate student research colloquium in person again. The Feng Graduate Research Colloquium has been a tradition in the Marine Sciences Department since 1996. Named after the first Head of the Department of Marine Sciences, Dr. Sung Y. Feng, the colloquium was started by Prof. Hans Dam. The colloquium acts as a conference in which students receive friendly, constructive criticism, and have the opportunity to work on developing their abstract writing, leadership, and scientific communication skills. The Colloquium is funded by the Department of Marine Sciences and the S.Y. Feng Scholarship Fund.

This years colloquium featured 16 oral presentations and 20 posters spanning the entire diversity of marine research in our department. Special thanks to the student organizers and Debra Schuler for the help behind the scenes.

See the colloquium list of talks and poster presentations, including abstracts


Our [student] Life on the Ocean


By Ewaldo Leitao.
When we say we work or study oceanography, it is common for us to be met with a: “Wow, you must spend a lot of time doing cool stuff in the ocean then!” Alas, most of us spend most of our time on a computer. However, cruises are still an essential part of oceanographic research to collect the necessary data or test equipment. In our department, many students have this opportunity to participate in such cruises; all with fascinating and unique research interests. Over the past year, several students joined cruises to get familiar with field techniques, collect their own data, or to better understand their study area. In this piece, graduate students in our Marine Sciences department shared their experiences in cruises that took place from Summer 2022 up to May 2023.

Graham Trolley, graduate student at the Dierssen OPTICS lab went on a cruise to measure microplastics optics in the great pacific garbage patch!

Graham Trolley preparing to deploy a neuston net to collect plastics for his spectrometry measurements.

An example of plastics collected during one of the net tow.

“In the Summer 2022 I participated in the Sea Education Association (SEA) summer cruise through the great pacific garbage patch, which sailed from Honolulu, HI to San Diego CA, starting In late June and ending in late July. SEA typically runs programs with undergraduates, who take part in cruises to learn about oceanography, sailing, and earn course credit. As a grad student, I was able to tag along as a visiting scientist and focus on collecting data.

My research focused on taking optical measurements, such as spectral reflectance, of freshly-collected plastic pieces. Previous work has been published on plastic spectral reflectance properties, but these measurements were made on dried and stored samples. Out in the environment, plastic pieces are likely to have some degree of biofilming growing on them. So, I sought to collect spectral reflectance measurements of freshly collected plastics in order to assess how the presence of biofilms might impact plastic spectral reflectance. Knowing this will be useful for sensitivity analyses seeking to develop a satellite-based ocean plastic detection algorithm.

During the cruise, I conducted daily neuston net tows to collect plastic pieces. Neuston nets are towed along the surface of the water to collect as many buoyant plastic pieces as possible. Once collected, I rinsed the plastics out of the net and into a bucket, then picked them out and aggregated them for spectral measurement.”

Mackenzie Blanusa (left) getting ready to deploy a mixed layer float on the SMODE IOP1 cruise.

Mackenzie Blanusa, physical oceanography graduate student, does a lot of math and computer work, but she had the opportunity to take part in two different cruises in the last academic year! She got some hands-on experience in the first one, and in the second she is participating in the cruise that collects data for her study area in the Brazil Margin.

“I participated in NASA’s Sub-Mesoscale Ocean Dynamics Experiment (S-MODE) IOP1 as part of the science party aboard the R/V Bold Horizon. The cruise took place from 10/06/2022 – 11/04/2022 in the Pacific Ocean, approximately 100 miles offshore of San Francisco, California. The focus of this experiment was to sample ocean fronts that are a few kilometers in size to study their dynamics and effects on vertical transport. The ocean fronts were sampled using aircraft, ship surveying, and autonomous platforms such as wave gliders, sea gliders, saildrones, floats, and drifters. I worked the night shift from 4pm – 4am, running an instrument called an EcoCTD, which measures temperature, salinity, pressure, chlorophyll, backscatter, and oxygen. I also helped with the recovery and deployment of wave gliders and mixed layer floats.

I am currently (03/06/2023 – 04/06/2023) aboard NOAA’s R/V Ronald H. Brown for U.S. GO-SHIP’s decadal reoccupation of A16N in the Atlantic Ocean. I am participating in the first leg of the cruise, sailing from Brazil to Spain. The second leg of the cruise will be sailing from Spain to Iceland. This is a longline hydrographic cruise, where we take CTD casts at many stations along the same longitude line. The CTD rosette has 24 bottles and is deployed to the bottom of the ocean. I am working with Dr. Chris Langdon’s research lab out of the University of Miami. The Langdon lab is leading measurements on oxygen, pH, and total alkalinity. I am overseeing pH measurements using a spectrophotometer. Other groups are taking measurements which include DIC, DOC, CFCs, velocity, temperature, salinity, and biological samples. The best part of my trip so far has been getting to explore Brazil, crossing the equator, and viewing beautiful sunrises every morning.”

Yipeng He, alumnus of the Mason Mercury Lab, studied air-sea mercury exchange in the ocean for his PhD, also had cool research experiences in cruises.

“I was on a scientific cruise - the GEOTRACES GP17 cruise, leaving San Diego (CA) on Nov 13 2022. Going from North Pacific to South Pacific, crossing the Equator, going further south and crossing the Antarctic cycle, and arriving at Punta Arena (Chile) on Jan 25 (2023). The boat was R/V Roger Revelle, which was my second time sailing on this boat. The first time was the GEOTRACES GP15 cruise in 2018. I was collecting samples and measuring atmospheric mercury species, air-sea exchange of mercury species and surface ocean Beryllium-7 profile.”

Yipeng He with his atmospheric Hg speciation system on R/V Roger Revelle during the GEOTRACES GP17 cruise.

Heat tolerance changes across environments and populations

March 27th 2023 - By Ewaldo Leitao.

Climate change is a threat to species persistence. Increasing temperatures affect species differently depending on their habitats, such as land or the ocean. However, species often consist of different populations (groups of individuals that reproduce together) that experience different temperature conditions. And if populations live in these areas long enough, they can genetically adapt to their local conditions. What does that mean? If the same species has a population in an area where it is constantly warm, like the tropics, and another population that lives in colder regions, like Connecticut, then we’d expect the tropical population to handle high temperatures better compared to the population living in colder regions. This kind of diversity within species affects how we think about the vulnerability of the species as a whole. To add another layer, if variation differs for terrestrial vs. oceanic species, we might be missing important information about where climate change will have the strongest effects on the planet.

Matt Sasaki looking at a water sample with a handheld microscope at Lake Okeechobee, FL.

That is what Dr. Matt Sasaki and collaborators investigated in a paper recently published in Nature Climate Change. Their main goal was to assess the heat tolerance (the highest survivable temperature) of populations in many different species, from different realms – terrestrial, freshwater, marine and intertidal. They assessed the vulnerability of species by surveying in the literature from the whole world that measured individual heat tolerance. They compiled and then conducted a meta-analysis of these published data, thereby assessing how the heat tolerance is related to the thermal environment these populations live in.

“This paper came out of the ‘Evolution in Changing Seas’ Research Coordination Network (RCN). Back in 2019 they brought some of us together at Shoal’s Marine Lab for a synthesis workshop and essentially told us to think about questions at the intersection of evolutionary biology and marine science”, said Matthew Sasaki, about the seed of the idea.

"I really enjoyed the collaborative aspect of this project, even though I’ve met most of the co-authors in person only once (or not at all!)"

By measuring how heat tolerance changes between populations of the same species, they found that marine and intertidal species show a decrease of heat tolerance between populations as the environment gets colder, but that was not observed in terrestrial and freshwater populations. This was an interesting result, because since the ocean is largely connected, they expected that there would be a smaller differentiation in the ocean compared to land, where geographical barriers can create physical separations, allowing difference in heat tolerance to build up among populations within a species.

Behavior may play a role in the observed patterns. In the terrestrial realm, many organisms can moderate body temperature by seeking shade and forested areas to find refuges from the heat. Even plants can exploit micro-climates. This decreases the amount of evolutionary pressure on terrestrial organisms, when compared to other realms.

Data surveyed to analyze global patterns of heat tolerance. The histogram on the left side shows the higher proportion of studies in the northern hemisphere (Modified after Sasaki et al. 2022).

This study highlights the importance of accounting for evolutionary processes in the context of climate change and species persistence and extinction risk. Larger differentiation of heat tolerance within species may suggest a potential for evolutionary rescue. That is, populations with genes that allow them to be “warm adapted” may rescue populations that are more susceptible to increasing warming.

We asked what was the coolest part about the execution and findings of the project. “This wasn’t a project someone could do alone, and it was really cool to be part of such a big collaborative effort. The findings themselves were also really exciting for us. We expected there to be pretty clear differences between marine and terrestrial taxa, but we were surprised to see that local adaptation seems to be stronger in marine species and not terrestrial species. This goes against some of the traditional paradigms (that marine species’ are more often homogenized by larval dispersal, for example), and hints at a cool role of behavioral thermoregulation in shaping patterns in evolutionary adaptation.”

“This was definitely a pandemic pet project. I won’t say the pandemic helped us make progress though. This ended up being something we worked on a little bit each week for a couple years. Maybe that helped us put together a more robust product (slow and steady wins the race?). I really enjoyed the collaborative aspect of this project, even though I’ve met most of the co-authors in person only once (or not at all!). Having to do everything virtually definitely changed the nature of the collaboration (more written exchanges, less whiteboard brainstorming) but I think we made it work. We’ve just started working together on a couple new projects that build from this initial work, so it must not have been too terrible.”, said Matt.

Sampling freshwater mussel gut microbiomes in the Great Lakes

In June 2022, Hannah Collins and Tyler Griffin from the Ward Environmental Physiology Lab went to Buffalo, NY, to perform research on the gut microbiomes of freshwater quagga mussels (Dreissena bugensis). The three-day trip involved collecting these invasive mussels from Lake Erie with the help of Brian Haas at the Buffalo State Great Lakes Center field station. The goal of the project, funded by an NSF Emerging Frontiers in Research and Innovation grant, was to sample mussel gut microbes before and after defecation with the goal of distinguishing between microbes that live inside the mussels and other microbes that were simply passing through. This work serves as preliminary research for the larger goal of investigating the feasibility of using freshwater mussels to remove microplastics from freshwater systems and co-concentration them with plastic-degrading bacteria.

PhD student Hannah Collins taking samples of mussel guts for microbiome analyses (Photo: Tyler Griffin)

quagga mussels
Invasive Quagga mussels (Dreissena bugensis)

niagara river
View over the Niagara River in June 2022

Jamie Vaudrey selected for Faculty Environmental Leadership Award


16 March 2023. DMS is proud to announce that Prof. Jamie Vaudrey has been selected for the 2023 Faculty Environmental Leadership Award (ELA). This award recognizes individuals who have worked alone or as part of organizations to support sustainability efforts at UConn and beyond.

Since 2005, the Office of Sustainability, within the Institute of the Environment has honored faculty members, students and staff members who have made a positive impact on the environment through their leadership in the classroom, lab, or in the communities which UConn serves

Dr. Vaudrey was nominated, because of her exemplary role as an environmental leader over the past years. She sets the standard for outreach in the Department of Marine Sciences. Communicating science is the fiber that runs through all of her research and teaching. She does this across a broad array of stakeholders often with competing interests. Her outreach extends well beyond advisory to active partnerships with citizen scientists, regulators, municipalities, and industry. It has helped to shape the stewardship trajectories of waters and watersheds regionally, and seagrass ecosystems worldwide.

Her leadership roles in professional societies and on advisory councils have pushed for more integration of scientific results into decision making and broadened participation of underrepresented groups in marine science. Dr. Vaudrey’s key role in gathering the momentum for establishing the Connecticut National Estuarine Research Reserve was her crowning achievement of years of meticulous, patient teamwork, where she led countless meetings to bring experts, policymakers and public stakeholders to the table and eventually, through dialogue and her own unique way of gentle persuasion, make the CT NERR a reality in 2022.

In addition, Dr. Vaudrey has led numerous, hands-on team efforts in recent years to work on sea grass restoration and living shorelines initiatives, where she has been inspiring students and volunteers by practically working alongside them in the field. Dr. Vaudrey’s compassion for nature and the future of Long Island Sound emanates from her everyday work, which is a key motivating force for every member of her team.

Dr. Vaudrey also works with Save the Sound and helped develop an Environmental Report Card for Long Island Sound which has engaged senators and other state and federal agencies to seek additional funding for research on environmental impacts on local waters. Jamie is also the Coordinator for the Niantic River Watershed Committee, and she is an outspoken advocate for environmental issues in our local marine waters. Her impact on understanding of environmental and sustainability impacts in CT’s local waters reaches far beyond the classroom, but she is devoted to educating the next generation of scientists and managers on these important issues.

Prof. Catherine Matassa wins UConn-AAUP Teaching excellence award


23 March 2023. DMS is proud to share that Prof. Catherine Matassa has been selected for a 2023 UConn-AAUP Excellence Award in the Early Career Teaching category. This is well deserved, because since joining our department, Catherine has distinguished herself as one of the most cherished, effective and innovative educators for undergraduate and graduate students of our Department and CLAS. Her enthusiasm for Marine Biology and her innovative approach to teaching Quantitative Methods and Experimental Design are a true enrichment to students and faculty alike.

Here are some excerpts of what colleagues and students had to say about Catherine's teaching:

"In addition to providing the foundational basis of marine ecosystems, she facilitates transformative learning experiences with hands-on laboratory and field activities where students apply their knowledge and conduct independent research. Courses where students conduct independent research require much larger investment of time and energy from the instructor." Prof. Heidi Dierssen

"Almost from the time I arrived at UConn in 1995, I heard colleagues in Marine Sciences discussing the need for an Experimental Design/Statistics course for our students. Being located at Avery Point has always limited our participation in Storrs-based classes, so we tried, and failed, several times to develop a course of our own. When Catherine arrived, the problem was solved. Her class, MARN 4210Q Experimental Design in Marine Ecology, covers the basics of hypothesis testing and gives students a good working knowledge of R, the state-of-the-art computing environment for scientific statistics." Prof. George McManus

"Catherine created the experimental design and analysis course to address the demand for a course that covered statistics, coding and design. The course provided us with real data to run analyses on in R and posed questions, which we addressed with experimental design. The homework was dynamic and helped me hone my abilities coding in R and interpreting statistical results. I took a statistics class during my undergraduate studies but gained a much better understanding of analyses with Catherine's hands-on approach." Kayla Mladinich, PhD student

"I took Dr. Matassa’s Marine Biology course in the Fall of 2022. I personally was impressed with how innovative and diverse the content that she included in the class was. The laboratory experiments perfectly complemented the lecture period and helped me relate the information on the slides to real life situations. The ability to write and explore our own independent projects as well provided creative freedom that many other class labs seem to be lacking, and she did well to encourage critical thinking and exemplify how our experiments relate to real marine problems. Her inclusion of science communication in the curriculum was also a refreshing innovation to the lecture period, and something I had not experienced before in a STEM class." Greg Aniolek, undergraduate student

"Dr. Matassa coordinated an engaging field trip to Avery Point that was an exciting opportunity for students to expand their knowledge outside of the classroom. This opportunity included a tour of the Long Island Sound on a Project Oceanography research boat. While the tour was guided by two Project Oceanography educators, Dr. Matassa took every chance to communicate additional information that related to our classroom studies and energetically answered the questions that were raised. Dr. Matassa had something interesting and relevant to say about every species that we collected on the boat." Lukas Liebowitz, Senior Biology Major 2023