Caption: Graphical abstract depicting that a multi-study analysis of raw 16S gut microbiome data collected from blue mussels revealed that depuration strongly influences the recovered microbial community.
Everybody poops, even mussels! And it turns out that whether a mussels has pooped matters a lot when you sample its gut microbiome. New research published in Environmental Microbiology by the Ward lab and lead author Tyler Griffin reveals that fecal egestion (or depuration) status of mussels is a critically important factor for determining the microbial community composition in the mussel gut. By performing a multistudy re-analysis of microbiome data from several projects conducted by the Ward lab over seven years, they were able to broaden the understanding of gut microbial dynamics of these foundational invertebrates in Long Island Sound. Link to the article.
A group of researchers at DMS joined together under Sandra Shumway and Evan Ward, critically reviewed 750+ publications on microplastics and molluscs in the field and laboratory. This incredible effort has resulted in a thoughtful review of the cluttered scientific literature. Many studies on suspension feeding molluscs and microplastics have perpetuated inaccurate findings based on inappropriate methodologies, poor animal husbandry, and misinterpreted results. All of these false conclusions have caused a damaging narrative for the shellfish industry, raising concerns about the safety of eating shellfish. While microplastics are ingested by shellfish, microplastics in molluscs are extremely low globally as these animals are capable of selective capture, ingestion, and egestion of particles. In reality, the number of microplastics inhaled and consumed by humans in everyday life far outweighs the number of microplastics found in shellfish. Recommendations were provided for future studies in both the field and laboratory that will prevent researchers from falling into the pitfalls discussed in this review. This review is presented from the perspective of experts on shellfish physiology and represents the opinions of, and assessments made by, the authors. The authors hope this review can be used as a starting point for those interested in furthering this field of research with thoughtful experimental questions. Link to the article.
Retiring Faculty Member – George B. McManus. Photo credit: Mengyang Zhou
By Mengyang Zhou
George McManus is retiring on February 1, 2024, after 28 years at the university. Graduate student Mengyang Zhou sat down with him to capture George’s reflection on his amazing career and find out what he plans to do next.
Mengyang: How did you decide to pursue a career in academia?
George: I was interested in environmental science and had a degree in biology. So I thought I might want to be an environmental lawyer, actually. Then I went to Stony Brook University to get a master’s degree in marine science before going to law school. But when I got there, I really liked science much more, and I said I don’t want to be a lawyer. So I stayed at Stony Brook and got my PhD in 1986. Then I had a postdoc in upstate New York at the Cary Institute, and another postdoc at the University of Maryland. Then I got a faculty job at the University of South Alabama. In 1995, I got the job at UConn, and I’ve been here since then. A lot of changes in that period of time. When I got here, I think there were maybe a dozen of faculty, and there was only one woman. They just started the undergraduate major, which was called Coastal Studies at that time, and they had the graduate program here. And when I started out, I was teaching two days a week at the Stamford campus. But then in 1998, I got transferred here to the Avery Point campus so I had my lab and my teaching here. And I’ve been just here ever since.
Mengyang: What are the changes that you saw in our department over the years?
George: One big change is that the faculty is much bigger now. Also, the undergraduate major has really grown. Now we have around 100 students in this major. A big change is this building. When I got here, there were two kind-of broken down buildings with not very good facilities, and they were crumbling. This building was started in 2001, I think. And it really made a big difference in the facility and labs. I used to be in another building that was taken down, and I could look out across here and see this new building going up. Sometimes I walked over here and stood here when it was just concrete and nothing else, so I knew I was going to be in this office. The department has also grown a lot in research funding. One thing that really hasn’t changed is that it’s still a relatively small department. And people still collaborate a lot with each other. When departments get big, they break down into different groups, and all of a sudden, you’re just a smaller part of the bigger group. But here it’s still small enough that people, from geochemistry or physical oceanography or biology, still talk to each other. The Avery Point campus itself has also changed a lot. The facilities have gotten a lot better. I think we’ve gotten higher quality students here.
Mengyang: Can you talk about how your research and the field changed over the years?
George: I am always interested in plankton. For my PhD, I studied little tiny flagellates that eat bacteria. And I was always interested in the food chain, the protozoa and how they fit into the food chain. The food chain in the ocean can be very long because it starts with tiny things and takes many steps before you get something big like a fish. I also did a master’s degree about copepods and copepod processing of PCBs (polychlorinated biphenyls), which is an environmental contaminant. I did a postdoc in upstate New York. It was a freshwater environment. I studied a little lake for a whole year, measuring who eats different kinds of bacteria and how the food chain was set up. And then when I got down to Maryland, I got interested a little bit in phytoplankton, because I was interested in using different phytoplankton pigments to identify which kinds of algae were there, and who was grazing on them by changes in the different pigments. Then I got interested in slightly bigger things like ciliates and other kinds of grazers. I continued that work when I went to Alabama.
One thing that I discovered in graduate school, but it was a side thing, not part of my dissertation, was that there were some ciliates that eat phytoplankton and they digest everything, but they keep the chloroplast, and the chloroplasts can still be functional. So they can photosynthesize based on the food that they eat. They’re called mixotrophs, because they’re eating but also photosynthesizing. And that was something I thought was really fascinating. It was an experience of discovery in my life. I remember looking in the microscope and putting on the fluorescent light and seeing all these chloroplasts inside of ciliates and I just ran out of the room to try to find somebody to show this to. But I didn’t really get back to that until I went on a sabbatical, when I was at UConn in 2002. And I was in Ireland, studying this little mixotrophic ciliate that lives in tide pools. And I started, also at the same time, collaborating with a person at Smith College, Dr. Laura Katz. She’s a molecular biologist. So I would pick these ciliates, and then she would sequence their DNA. And one of the things we found out is we could sequence the chloroplast and find out what kinds of algae they were eating. Huan Zhang and Senjie Lin also helped me with this. It turns out, they’re eating macro algae. They actually eat the spores from seaweeds. We could tell that from the genome of the chloroplast. And from that point in the early 2000s, I really kind of focused on using molecular methods to document diversity of protozoa, especially ciliates in the natural environment. I still always had an interest in the food chain, and I did some work in Brazil with Hans Dam (also a faculty member in our department) on the tropical upwelling system and how the food chain is structured there. But mostly, a big part of what I have been doing is cultivating the organisms. We’ve had a long time series out here at the dock on campus, collecting ciliates, trying to culture them and identify them. Then we barcode them, in other words, we take a piece of the DNA that we sequence, and that lets us identify them. If we get the same thing later, we can verify from the DNA. So I think my lab developed kind of a specialty in being able to cultivate these organisms because they’re very, very fastidious, and hard to cultivate. And then especially with collaborations with my colleague at Smith College, being able to sequence them and eventually we got to where we could sequence the whole genome or the whole transcriptome. When we first did that, the Moore Foundation funded a study of eukaryotic plankton transcriptomes. Anybody who had anything in culture that they wanted to sequence, the foundation would do it. We had the ciliate that I talked about, that grows in the tide pools and eats seaweed. We had them in culture, but to collect enough RNA, I would have to filter quite a bit and they don’t like to be caught on a filter. They kind of blow up on the filter and they don’t like to be centrifuged. So I picked individuals and I had to pick 22,000 of them. I picked maybe a couple of 1000 every day for two weeks. Within a couple of years, now you can just pick one and get the whole transcriptome from the methods people have now. So even in the short time of my career, things have changed so dramatically. We have a lot of new tools now to look at the genes and the gene expression in these organisms, not only in culture, but also we’ve been on cruises on the shelf here and collected things and sequence them from that.
Mengyang: What are the things you are going to miss after retirement?
George: I’ll miss the people. One of the things that I really hated about COVID was that everybody was working remotely. And that just does not suit me. From the very beginning, the university let people back into their labs if they had things like cultures to maintain, and I was basically coming in every week. But there weren’t too many other people here. I missed the people because of all the years before and even now since COVID is pretty much over. You see people and interact with them. I will still come in for the first year or two, and go to seminars and talk to people. But I think I won’t be active in the research part of it. I may go to some meetings, but I’m not going to keep any more cultures. I’m part of the SCOR working group. SCOR is the Scientific Committee on Oceanic Research. It’s an international organization. The NSF (National Science Foundation) funds these working groups on specific topics. The one that I’m involved in, with another year and a half to go, is about mixotrophs, organisms that both feed and also photosynthesize. I’ll have a meeting in Brazil next year, and maybe another meeting in Asia after that. So I’ll still be active intellectually, but probably not be doing research directly.
Mengyang: Do you have some final words to reflect on your academic career?
George: I think I’ve been very lucky that every day that I got up, I drove to work and I was happy. I always look forward to what I am going to do today. And it’s a tremendous privilege to have that. And kind of to earn your keep, you teach and you have graduate students and so forth. And that’s also fun. I love doing that. I don’t know if in the future, the structure will be quite the same. There’s more of a movement towards having teaching faculty and then research faculty. I’m not sure if the tenure system is going to stay in there. I hope it does. I hope that young people still have the same opportunities I had. It’s been a really great career and I wouldn’t change anything about it. I really enjoyed it.
Our PhD student Anagha Payyambally was featured in UConn Today to celebrate her achievement of receiving the Quad Fellowship. Anagha is one of only 100 recipients out of over 3000 applicants to receive this fellowship to her graduate studies. This new fellowship program supports exceptional students who are citizens of the United States, Australia, India, and Japan to support their graduate studies in the United States and build collaboration among scientists and technologists.
Read the story here with quotes from Anagha and her advisor Dr. Manning. Congratulations, Anagha!
On 24 August, 2023, 10 community science organizations, the Connecticut Department of Energy and Environmental Protection (CT-DEEP) and the University of Connecticut collaborated to simultaneously sample total alkalinity in the embayments and rivers bordering Long Island Sound (LIS). Led by DMS PhD Candidate Lauren Barrett, the event was a regional repeat of the 2019 effort led across New England by the Northeast Coastal Acidification Network (NECAN, http://necan.org/ShellDay).
The participating groups sampled for total alkalinity (TA) and hydrographic variables such as salinity and temperature during low, mid-, and high tides, meaning the spatial variation in alkalinity across the Sound. Seawater alkalinity requires high precision, expensive instrumentation and a skilled analyst, and thus typical observations of TA in LIS conducted by a single or a few researchers require that spatially separate samples also have a temporal difference. However, TA varies across diel and tidal cycles, so the spatial and temporal difference is important to parse. The collaborative effort of Shell Day allowed for a spatial identification of TA trends in LIS without the confounding temporal variation.
Shell Day 2023 was a successful event. Despite some mild rain in the afternoon, community scientists weathered the storm and still provided high-quality samples, which are currently undergoing TA analysis at UConn. The results of this work will be interpreted in the context of open LIS data (available through the Vlahos lab at UConn) and the data collected during Shell Day 2019. This work will be presented to the LIS Science Technical and Advisory Committee (STAC) this fall as well as to the participating organizations at a meeting which is to be determined.
Ann Bucklin, Professor Emeritus of Marine Sciences, has been appointed U.S. Academic Delegate to the International Council for the Exploration of the Sea (ICES https://www.ices.dk). This appointment, made by the Department of State on August 17, 2023, authorizes Prof. Bucklin to serve as one of the two U.S. representatives on the ICES Council, which is the decision and policy-making body in ICES. The U.S. Academic Delegate is focused on encouraging and coordinating ICES-related research and activities in the academic community.
What is ICES and its mission?
ICES is a leading multidisciplinary scientific forum for exchanging information and ideas on all aspects of marine sciences, including environmental, scientific, fisheries, wildlife, and conservation affairs, pertaining to the North Atlantic Ocean, including the Baltic Sea and North Sea. Principal functions of ICES, since it was established in 1902 and continuing to the present time, are to: 1) promote, encourage, develop, and coordinate marine research; 2) publish and otherwise disseminate results of research; and 3) provide non-biased, non-political scientific advice. The ICES mission and goals are guided by a Strategic Plan, which identifies and addresses critical themes in science, collaboration, advice, data, communication, and service support. See: https://www.ices.dk/about-ICES/how-we-work/Pages/Our-strategy.aspx
How is ICES organized?
The principal decision- and policy-making body of ICES is the Council, which consists of a president and two delegates from each of 20 member nations across Europe and North America. One of the U.S. delegates is a federal employee and the other represents the academic community. The mission of ICES is accomplished by various committees and working groups. The Advisory Committee (ACOM) provides advice on fisheries and marine ecosystem issues. The Science Committee (SCICOM) oversees all aspects of the scientific work. Steering Groups coordinate more than 100 expert groups covering most aspects of the marine ecosystem that work under them. The scientific work of ICES is done by a community of more than 1,600 marine scientists from research institutes and universities in member and affiliate nations collaborating in expert working and study groups.
What’s the focus of your research and its relevance to your appointment as U.S. Academic Delegate?
My research focus is molecular analysis of biogeography and biodiversity of marine zooplankton, including population genetics of important species (especially copepods and euphausiids), local-to-global patterns of species diversity, and analysis of pelagic food webs based on DNA barcoding and metabarcoding. An important focus is time-series analysis of marine zooplankton species biodiversity, with applications for ecosystem monitoring and fisheries management on the NW Atlantic continental shelf. I have been a member of the ICES Working Group of Zooplankton Ecology (WGZE) and Working Group on Integrative Morphological and Molecular Taxonomy (WGIMT) since 2007; I served as Chair of WGIMT during 2014-2017. I am a grateful recipient of an ICES Service Award (2018) and an ICES Outstanding Achievement Award (2019). See: https://marinesciences.uconn.edu/person/ann-bucklin/ and https://en.wikipedia.org/wiki/Ann_Bucklin
What are your thoughts about being appointed the U.S. Academic Delegate?
I have participated in ICES activities for many years. The ICES Annual Science Conference (ASC) is a valuable forum for the exchange of research results and exploration of important applications for ecosystem assessment and fisheries management. I am honored to have been appointed as the U.S. Academic Delegate and look forward to contributing to the ICES organization. A primary goal is to encourage broader participation from the U.S. academic community, including active researchers, Early Career Scientists, and students.
Mengyang receives best poster award. Photo credit: Molly James
Congratulations to Mengyang Zhou on receiving the best poster award at the recent Gordon Research Conference on Coastal Ocean Dynamics (link:https://www.grc.org/coastal-ocean-dynamics-conference/2023/) in June of 2023. His poster entitled “Constraints on the bottom water residence time in an economically-important embayment of the Southern Benguela Upwelling System” is work that is part of an NSF-funded project led by Pf. Julie Granger (link: https://granger.lab.uconn.edu/) and Pf. Samantha Siedlecki (link: https://samanthasiedlecki.wixsite.com/coastalbiogeodynlab/about-us) in partnership with colleagues at the University of Capetown. Mengyang ran a series of particle tracking experiments in a high-resolution simulation to quantify the residence time of bottom waters plagued with hypoxia. Interannually, years with short bottom water residence time experienced little hypoxia. This work is part of his Ph.D. dissertation research with Pf. Julie Granger.
Congratulations to Brendon Goulette, an undergraduate student in our department who was awarded a Connecticut Sea Grant Undergraduate Research Fellowship for the work he is doing with Professors Catherine Matassa and Samantha Siedlecki and PhD student Halle Berger. Brendon is researching how climate change is affecting sea scallops, a significant commercial fishery in New England.
Congratulations to Professor Samantha Siedlecki who was recently awarded tenure and promotion to Associate Professor from the University of Connecticut! We are so proud to have Prof. Siedlecki as a member of our department and to see her awarded tenure.
Professor Siedlecki has been a highly valued member of our department since her arrival at UConn in 2017 and has played many leadership roles in our department and the broader scientific community. Dr. Siedlecki’s research group focuses on coastal biogeochemistry using a combination of simulations and observations to characterize historical and ongoing change and forecast future trends. A particular focus of her group’s work is on coastal carbon and oxygen cycling, including the impacts of decreasing ocean pH (ocean acidification) and decreasing oxygen (deoxygenation) resulting from climate change and other human impacts.
Her research accomplishments have been recognized through an Early Career Faculty Innovators Program Fellowship from NCAR and a Kavli Fellowship from the US National Academy of Sciences. Since her arrival at UConn, she has received approximately 16 grants totalling over $4 million in funding from organizations including NOAA and NSF, including serving as co-lead PI on a $1 million grant on assessing the vulnerability of sea scallops to ongoing ocean change.
Her teaching contributions have included developing two new courses, Ocean Expedition (a very popular course for our graduate students) and Biogeochemical Modeling, and teaching Environmental Reaction and Transport, a course that allows undergraduate students to develop their quantitative and problem solving skills. She has mentored numerous personnel in the department, and currently supervises two PhD students, one masters student, one research associate, one research scientist, and multiple undergraduate students.
Dr. Siedlecki has been highly active in departmental service, having served on several departmental committees, including the Advisory Committee to the Head, and was a founding member of the department’s Justice, Equity, Diversity and Inclusion committee. She was recognized with a Climate, Diversity, Equity and Inclusion Award from the UConn College of Liberal Arts and Sciences in 2022 due to her contributions to fostering an inclusive climate in our department and at UConn. Outside of UConn, she has had substantial contributions to research organizations and activities at the regional, national and international level, including serving as co-coordinator for the Northeast Coastal Acidification Network (NECAN) and serving as a member of the international scientific committee for the 5th International Symposium on Oceans in a High CO2 World, and also gave an invited plenary presentation at this conference. Dr. Siedlecki makes stakeholder engagement and outreach critical components of her research program and has participated in numerous outreach activities with members of the aquaculture industry and management organizations along with members of her research group.
Dr. Siedlecki has co-authored approximately 36 publications and some of her recent publications are listed below.
Now that she has been awarded tenure, Prof. Siedlecki looks forward to finalizing her group’s work with east coast coastal communities through a regional vulnerability assessment of scallops and the communities who rely on them. She plans to conduct similar assessments in other regions with the international research community and is currently preparing a proposal with South African colleagues. Congratulations to Dr. Siedlecki! We are excited to watch the future accomplishments by you and your team!
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!
Caption: Graphical abstract depicting that a multi-study analysis of raw 16S gut microbiome data collected from blue mussels revealed that depuration strongly influences the recovered microbial community.
