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‘To Benefit the Earth and Those Upon It.’ Announcing the 2020 Muckenhoupt Scholarship Winners.

Congratulations to Allison Noble and Haley Bayne, this year’s recipients of the Dr. Carl Muckenhoupt Scholarship!

The Muckenhoupt Scholarship is awarded each year to Northeastern undergraduate students who will use their training in science “to benefit the environment of the earth and those upon it.” The 2020 recipients were chosen from an impressive pool of academically exceptional and environmentally inclined students.

Allison Noble (’21), Marine Biology

Allison Noble (2021) is a Marine Biology student who has worked on several projects with the Marine Science Center, including research internships in the Hughes Lab and the Kimbro Lab.

Noble says she has most appreciated the opportunities to do field work in a diverse array of different ecosystems, especially the oyster reefs in both Florida and Rhode Island. Her work studying stony coral tissue loss disease was featured in a news feature earlier this year.

Noble’s latest project, in collaboration with Jeriyla Kamau-Weng, another Northeastern student, is development of the Marine and Environmental Sciences Peer Mentoring program. The program — the first of its kind in the College of Science — will be launched in the fall and already has over sixty participating students!

This summer, Noble volunteered at the Trevor Zoo in Millbrook, NY for the third year in a row, and participated in a virtual internship with the National Oceanic and Atmospheric Administration (NOAA) researching soundscapes in areas with varying levels of habitat degradation at the Waquoit Bay National Estuarine Research Reserve. Her sound ecology work will continue this Fall with a co-op at the Woods Hole Oceanographic Institution researching sensory and sound ecology on coral reefs.

Allison Noble in Bocas Del Toro. Photo by Tim Briggs

 

Hayley Bayne (’20), Environmental Science

Haley Bayne (2020) is an Environmental Science student with interests in sustainability, ecology, and science communication.

She has enthusiastically seized opportunities for study and field research abroad during her undergraduate degree. One of her favorite experiences was a Dialogue course in Iceland, where she explored local geology and was inspired to consider ways that sustainable energy practices in place in that country could be and applied in the United States.

Bayne also worked in the Rosengaus Lab studying antifungal mechanisms in termites, where she honed her research skills, mentored younger students, and produced a research paper which will be published later this Fall.

Last year, she was invited to attend a research conference in the Netherlands, where she was able to attend lectures as well as network with researchers at the top of their fields. Bayne is currently taking virtual classes at Northeastern in addition to exploring new interests and developing her skills in science communication and lab research.

Congratulations to both of these scholars on receiving the 2020 Muckenhoupt Scholarship and for all of their exciting research! With co-op and research experiences throughout their time at Northeastern, these students With co-op and research experiences throughout their time at Northeastern, Bayne and Noble are well prepared to make a positive impact with their future work.

 

Hayley Bayne in Iceland. Photo courtesy of Hayley Bayne.

 

They’re Planning to Build a New Space Station… at the Bottom of the Ocean

When we wanted to study space, we built the International Space Station—a place where astronauts could live, work, and conduct long-term experiments without having to return to Earth.

What if we had something similar on the bottom of the ocean?

Fabien Cousteau, a renowned aquanaut, environmentalist, and documentary filmmaker (and grandson of Jacques-Yves Cousteau), has been envisioning exactly that. And Northeastern is helping to make it a reality.

The rest of this story can be read here

Women in Science: Water Stewards

In case you missed it, here is  part one and part two of our series.

Building Knowledge and Pathways to Positive Change

Women make up less than a third of the global research population, but scientists at Northeastern University’s Department of Marine and Environmental Sciences are driving the change in that statistic through their innovative, successful research and their contributions to a thriving STEM pipeline for young women and future researchers.  This Women’s History Month, we’re highlighting faculty who are advancing scientific knowledge and removing barriers for the next generation of women in STEM.


How are humans impacting the waterways we depend upon, and how can we ameliorate these impacts?

Featuring Dr. Loretta Fernandez

June 27, 2014- Northeastern assistant professor Loretta Fernandez’ water quality samplers are deceptively simple: they’re providing powerful data about the contamination levels of polluted waterways.

Dr. Loretta Fernandez is working to answer those questions and communicate
critical information to the stakeholders and stewards of our shared waterways. Her work
utilizes environmental organic chemistry to pioneer passive sampling methods for organic
contaminants in water and sediment, as well as monitor the transport, transformation, and
biological exchange of organic contaminants in our environment. Dr. Fernandez recently
developed a straightforward method for determining the concentration of contaminants most
likely to end up in the tissues of organisms living in polluted waterways, providing crucial
pollutant data to the EPA and other researchers. She is currently collaborating with the Munoz
Lab at the Marine Science Center to examine industrial contaminant mobility across the land
sea interface; these contaminants are detrimental to human and ecosystem health, and are
mobilized by geomorphic and biochemical processes for decades. Fernandez and her
collaborators are examining the stability of these compounds in floodplains and the coastal
ocean at several locations across New England and the Atlantic Coastal Plain.

Dr. Fernandez has been an active part of connecting environmental science with students and
with the local community. She has presented hands-on water quality activities at the Marine
Science Center Open Houses, and has been a mentor for young women at various science
career stages. Recent undergraduate research assistants in her lab have gone on to pursue
graduate research at Harvard, Yale, MIT, Colorado School of Mines, and Univ. of California
Santa Cruz. Creating pathways to success for young researchers is one of the ways Dr.
Fernandez is helping ensure that the environmental systems around us have scientific sentinels
into the future. Dr. Fernandez recently turned her lab’s expertise in environmental pollutants
into an innovative solution for testing facemask effectiveness against the COVID-19 virus,
working with Dr. Amy Mueller and a team of engineering students to modify their software to
assess particle movement through the masks, and establish the best materials for protecting
people against an airborne virus.


How can we measure, characterize and understand the huge and heterogeneous system of our earth?

Featuring Dr. Amy Mueller

Dr. Amy Mueller works to tackle these complexities by enabling critical
environmental measurements of the water in natural systems around us and in the built
systems we use each day, and enabling optimization of infrastructure like stormwater sewers
and wastewater treatment plants.  Dr. Mueller’s Environmental Sensors Lab is developing new
sensors, instruments, and signal processing strategies to optimize our ability to study the
natural and built environments. Her sensor development space at Nahant’s Marine Science
Center and chemistry labs on the Boston Campus provide space and infrastructure to bring
together engineers and scientists from a variety of disciplines to tackle critical challenges. Dr.
Mueller and her team are advancing our understanding of nutrients in ocean ecosystems by
developing an in-situ trace-metal clean sampler capable of automated sample collection and
now working on nitrogen nutrient sensors to support more environmentally friendly
aquaculture pens. On the wastewater front, she is working with collaborators at the University
of Washington and a number of operating treatment facilities in New England to validate novel
sensor systems for use in current next-generation wastewater treatment reactors. Dr. Mueller
recently combined labs and expertise with Dr. Loretta Fernandez into an innovative solution for
testing facemask effectiveness against the COVID-19 virus, modifying their software to assess
particle movement through the masks and establish the best materials for protecting people
against an airborne virus.

Dr. Mueller is active in efforts to communicate science to community stakeholders and students
alike.  She has shared her innovative water monitoring work with attendees at the Marine
Science Center’s public lectures and open house series, and is co-leading a wastewater
treatment workshop series bringing together regional plant operators, engineers, instrument
experts, and researchers to discuss the challenges and opportunities in the

A 10,000-mile Journey for Microbes

“I think it’s incredible how much power they [microbiomes] have,” says Andrea Unzueta-Martinez, a doctoral candidate at Northeastern’s Marine Science Center.

Unzueta-Martinez spent three months at the Port Stephens Fisheries Institute raising oyster larvae to try and figure out how they acquire their microbiome.

Andrea Unzueta-Martinez uses a microscope to observe Sydney rock oyster larvae.

Andrea Unzueta-Martinez uses a microscope to observe Sydney rock oyster larvae.

The term microbiome refers to the billions of microscopic colonists that inhabit every living creature. Even your own body is teeming with bacteria, viruses, fungi, and archaea—they make up more than half of your cells.

This story was originally published on [email protected] on April 21, 2020. Continue learning about Andrea Unzueta-Martinez-Martinez’s unique experience in Australia here!

Women in Science: Communicating our Impacts on Marine Communities

In case you missed it, here was part one of our series.

Building Knowledge and Pathways to Positive Change

Women make up less than a third of the global research population, but scientists at Northeastern University’s Department of Marine and Environmental Sciences are driving the change in that statistic through their innovative, successful research and their contributions to a thriving STEM pipeline for young women and future researchers.  This Women’s History Month, we’re highlighting faculty who are advancing scientific knowledge and removing barriers for the next generation of women in STEM.


How do human activities alter the structure and function of microbial communities, and how can microbial communities ameliorate anthropogenic pollution?

Featuring Dr. Jennifer Bowen

“The most rewarding part of being a mentor to me is in cultivating my student’s intellectual curiosity and watching them build the self-reliance and expertise they need to be successful.” – Dr. Jennifer Bowen

Dr. Jennifer Bowen and her research team seek answers to these questions, and the marshlands of the greater Boston area are an ideal landscape to find the answers.  Dr. Bowen’s work with a long-term nutrient enrichment experiment at the Plum Island Long-Term Ecological Research site North of Boston looks at the impact of coastal eutrophication on salt marsh ecosystem sustainability, and her work at Revere’s Rumney Marsh and other restored marshes in the region quantifies how these restorations alter the capacity for marshes to remove land-derived nitrogen.

In one recent study, Dr. Bowen and Dr. Ashley Bulesco, then Bowen Lab PhD candidate and now faculty at Eckard College, determined that nitrate enrichment in coastal systems is stimulating a shift in the microbial community and an increase of microbes responsible for decomposition. Given the essential ecosystem services provided by salt marshes, particularly their potential for carbon storage and natural nutrient filtration, the ongoing research by Dr. Bowen and her lab is providing critical information for scientists and resource managers seeking to prepare for the impacts of climate change.

Dr. Bowen’s early experiences with nature on her family’s farm in rural Maine played an important role in her path to becoming a scientist and educator: “Observing nature, drawing connections between seemingly disparate ideas, and learning to problem solve help me be a successful scientist.” She has consistently worked to bring these skills to her own students, and to make complex research more accessible to non-academic audiences. She translated her recent Nature Communications study analyzing microbial communities of the invasive Phragmites grass into a piece for the Environmental Science Journal for Teens, and her lab group translated their nutrient cycling research into fun educational activities for high school students attending last summer’s Coastal Ocean Science Academy at MSC. 


How will the inhabitants of marine ecosystems, namely fish, respond to pollutants – and how can we share this science with the next generation of ocean stewards?

Featuring Dr. Tara Duffy

“I often reflect back on the factors that sparked by interest in science and what has allowed me to be successful. It comes down to my fortunate interactions with curious, inspirational, and supportive mentors – both male and female. I try to offer to my students what these meaningful scientists in my life have given to me.” – Dr. Tara Duffy

Dr. Tara Duffy is interested in the molecular, individual, and population responses of fish and other marine animals to various pollutants, and what these responses can tell us about the ecological and evolutionary challenges they face. A 2016 study by Dr. Duffy and collaborators examined bay anchovy, an ecologically important forage species in Gulf of Mexico estuaries. The bay anchovy has a protracted spawning season and small eggs and larvae that likely encountered oil and dispersants during the Deepwater Horizon oil spill. They determined that bay anchovy larvae are sensitive to oil pollution and that this species could be important for understanding population level impacts in the system.

Dr. Duffy brings her research experience and her passion for teaching students to communicate science into the classroom, leading impactful courses at Northeastern in marine biology, zoology, evolution, and food security and sustainability. Her Dialogues course introduced students to food systems and conservation biology in Greece and Romania.

She also goes beyond the classroom to connect students to the science and each other, collaborating with others on the MES Diversity & Inclusion team to pioneer peer mentoring and inclusiveness initiatives. Dr. Duffy also serves as the Faculty Head for the Three Seas Program, teaching Marine Invertebrate Zoology and Botany to prepare graduate and undergraduate students for  inquiry-based and experiential curriculum. Dr. Duffy and the Three Seas team provide students with opportunities to do hands-on marine science at world-renowned research facilities, bringing the science happening in the field and lab directly to the future stewards of marine science and conservation.

 

Women in Science: Sentinels for Biodiversity

Building Knowledge and Pathways to Positive Change

Women make up less than a third of the global research population, but scientists at Northeastern University’s Department of Marine and Environmental Sciences are driving the change in that statistic through their innovative, successful research and their contributions to a thriving STEM pipeline for young women and future researchers.  This Women’s History Month, we’re highlighting faculty who are advancing scientific knowledge and removing barriers for the next generation of women in STEM.


What are the causes and consequences of changes in marine biodiversity, and how can these factors be applied to habitat restoration?

Featuring Dr. Randall Hughes

“I am personally fascinated and intrigued by the minutiae of science – what happens when we change one tiny part of a system, such as the identity of a blade of grass, and why? I find that sharing that information with students and figuring out ways to apply it to real-world problems are the most rewarding aspects of what I do.” Photo by Adam Glanzman/Northeastern University

Dr. A. Randall Hughes uses lab and field experiments, molecular techniques, and data synthesis to address these questions by examining the interactions among the numbers and identity of species, the genetic individuals that make up those species, and the ecosystem services that they provide.

Coastal ecosystems are shaped by the interplay between ecological and evolutionary processes, and Dr. Hughes is helping understand these interactions and apply that information to management and conservation.

For example, long-standing work in the Hughes Lab has demonstrated that seagrass (Zostera marina) genetic diversity leads to enhanced response of the seagrass ecosystem to a wide range of disturbances. Recent experiments indicate that seagrass genetic diversity also confers resistance to wasting disease, which nearly eliminated seagrass along the eastern coast of the US in the early 1900s.

Genetic diversity is also important for the survival and growth of Eastern oysters (Crassostrea virginica), as highlighted in studies conducted with the Kimbro and Grabowski Labs at Northeastern. The Hughes Lab is currently working in partnership with state resource management agencies in MA and RI to find feasible ways to apply these findings to enhance restoration success of both seagrasses and oysters. In addition, Dr. Hughes is collaborating with the Scyphers and Grabowski Labs at Northeastern to break down the documented gap between our scientific understanding of the importance of biodiversity and the application of this information to habitat restoration practice.

Dr. Hughes serves as the Chair of the department’s Diversity and Inclusion Committee, which works within MES/MSC to welcome, celebrate, and foster equity and diversity by providing diversity & inclusion resources and programming, facilitating mentoring and exchange within the department, and building the sense of community across the research disciplines and career stages represented on our campus.


How has climate shaped marine biodiversity in the past, and how will a rapidly changing climate affect biodiversity in the future?

Featuring Dr. Katie Lotterhos

When asked what motivates her research and collaborations, Dr. Lotterhos simply answered “I love data.”

Dr. Katie Lotterhos and her research team seek to address these complexities and to improve predictability and analysis of complex marine systems by using theory and experiment to inform each other and using novel statistical methodology to integrate data across biological, spatial, and temporal scales.

Research in her lab is driven by a desire to address the most central problems plaguing environmental systems.  Many of these problems arise from the threat of global environmental change on marine and terrestrial species alike.  As marine species are threatened by ocean acidification, warmer temperatures and lower oxygen levels, the Lotterhos Lab is investigating how intraspecific biodiversity – diversity between individuals within a species – can play a role in their responses to environmental change.

She is currently working with researchers from 12 institutions to analyze the genetic sequences of oysters, looking for adaptations within the species, and her recent analyses of genome scans on cod and other species provided key insights to help advance statistics analysis of DNA across many disciplines.

Dr. Lotterhos is a mentor for women in science at every career stage; in addition to PhD and Post-Doctoral candidates, her lab frequently hosts undergraduate researchers and, most recently, a high school intern from Essex Tech, Ellie Clark.

For the past two years, Dr. Lotterhos and her team have orchestrated impactful STEM workshops for high school girls supported by funding from the National Science Foundation.  These Evolution in Changing Seas workshops have introduced these young women to the evolutionary research ongoing at the Marine Science Center, and offered hands-on training with pipetting, DNA extraction, and coding.

 

From “Eww” to “Whoa”: Reflections on our School to Sea Programs

“Whoa, what is that? Ewww – It’s so slimy!”

The first reactions students have to the animals in our touch tanks are all over the map, and the first comments from this group of high schoolers were no different. We had just introduced a group of 10 sophomores to the marine animals in our touch tanks, including our Calico lobster named Marshmallow, and our extremely slimy Moon Snails.

This was the second rotation of three for these visiting students, who were visiting the Marine Science Center as part of the School to Sea program with Lynn Public Schools, funded through a generous grant from the Filene Foundation. This past Fall, we hosted nearly 500 students to introduce them to the marine environment from a scientific perspective.

Students learned about the intertidal zone in the classroom and then experienced those lessons first hand out in the field. During the classroom visits, the students learned about the different habitat elements that make up the intertidal zone on a rocky shore, then practiced with the tools that they would be using for data collection during their field visit.

After classroom visits, the students and their teachers visited the Marine Science Center and used their new knowledge of the intertidal zones and scientific data collection tools to explore tide pools and collect data.

The students were also led on tours of the Marine Science Center research labs and facilities, and learned about the history and geology of East Point and the region. The students learned about the work that MSC researchers are doing, including the robot mussels from the Helmuth Lab, the Antarctic Ice fish research in the Detrich Lab, the sediment coring done by the Munoz Lab.

The tidepools featured a variety of marine invertebrates, depending on the day, time, and tide – knotted wrack and other seaweed was always present, as well as small litorina snails and mussels, but some students were lucky enough to find sea stars, and well-camoflagued spider crabs. Some even made it their goal to find as many crabs as they could.

After the tidepool exploration and outdoor tours, students visited our touch tanks to see some other animals that didn’t happen to be in the tidepools that day, and some that don’t usually live in our intertidal. This is where the best exclamations happened – the “ewww” from before was thanks to one of our two Moon Snails.

These snails have a distinct round ‘moon-shaped’ shell, and exude a slimy secretion. They are predators, and eat by surrounding mollusks (often mussels) and drilling a hole into the shells to access the meat of the mollusks inside. We told the students this and showed them some empty mussel shells with the tell-tale hole.

When they saw the perfectly round holes bored through the shells, the “ewwws” changed to “whoas.” It was especially rewarding to see some of the students who started out the day being nervous touching the animals, then became comfortable enough to challenge themselves to hold some of the animals after being shown the proper technique by the outreach staff.

All of this was possible due to our partnership with Lynn Public Schools and the generous funding provided by the Filene Foundation. Thanks to this support, the students who took part in the program gained more than just a day at the seashore and new marine biology vocabulary. They gained a sense of place in their local environment, new knowledge about the ocean and its inhabitants, and a feeling of stewardship over the marine habitats around them.

Sierra Muñoz

Food, Forests and Fisheries: A Journey In Conservation and Food

Among budding wildflowers stood Vlad, a man waving a long metal hook as he gestured excitedly at our group. Despite him being slightly shorter than me and capped with a large and friendly-looking sunhat, I couldn’t help but feel intimidated. Laughing, Vlad explained how he voluntarily chased off poachers out of this wetland with the same hook before being hired as a field biologist and educator. I looked around me at the low bushes, marshes, lakes, and the trees that only barely concealed the skyscrapers of Bucharest towering around us and wondered what exactly I had gotten myself into.

My dialogue of civilizations was quite simply an experience that I couldn’t have gotten anywhere else. We began our journey in Romania at Văcărești Nature Park, an accidental wetland in the vibrant capital of Bucharest. Next, we headed into the Făgăraş Mountains. There, we worked with Foundation Conservation Carpathia (FCC), an organization that is working to protect the Carpathian Mountains and its biodiversity, with the goal of establishing the largest forested national park in Europe. Our typical day would consist of a group breakfast and paper discussion with our dialogue leader, Dr. Tara Duffy, followed by a day of hiking, exploring, and learning from a team of biologists, rangers, and conservations experts. I learned about invasive species, tracking and monitoring large carnivores, ecosystem services, and biodiversity indicators, which are traditional aspects of conservation biology. The FCC team took this several steps further, talking to us about government policy and the distinction of protected lands, what that means for the people who use or own these lands, and how the communist history of the country has influenced conservation.

The best part was that most of the learning was done in the field; I was able to see the concepts that we discussed in action. I hiked in ‘virgin’ beech forest, waited quietly in a bear hide, and collected samples with field rangers patrolling for scat, fur, and DNA of wolves, bears, and lynx. Most of the field professionals we worked with were locals, so I also learned about herbal medicines, how to dance traditional Romanian folk dances, and a two-way exchange of knowledge. One of my favorite memories is of the time I got to hear a traditional Romanian folk band while sitting on hay bales at a working farm. After the performance, I was able to talk with the group about music, tradition, and learning.

Next, we flew to Greece, learning about food sustainability in the Mediterranean with NYT bestselling author, Paul Greenberg. We started on the large island of Crete to focus on the definition and evolution of the traditional Mediterranean diet. This part of the dialogue was built mostly around outings to farms, wild areas, and even locals’ homes. I learned from different professionals each day on site visits to the Hellenic Centre for Marine Research, local markets, and olive oil processing plants.

Heading to a snorkel site on the island of Crete. For being an oligotrophic (low nutrient) sea, we found a lot of sea cucumbers and other fauna! Photo from Caitlyn Ark

Heading to a snorkel site on the island of Crete. For being an oligotrophic (low nutrient) sea, we found a lot of sea cucumbers and other fauna! Photo from Caitlyn Ark

We examined how the Mediterranean diet has evolved due to globalization, tourism, and climate change. This was intertwined with cultural experiences; hiking the Samaria Gorge, snorkeling in caves, and visiting the Minoan Palace of Knossos. Learning about the historic culture was crucial to my understanding of the Mediterranean diet. We visited ancient cemeteries and historical sites to look for evidence of food and what that meant to Greek culture to frame our investigation in a historical context.

This is us building nesting sites for European pond turtles in Văcărești. These specific sites are on an east-facing slope, which is favorable for the temperature and incubation of the turtles, and will hopefully boost the hatching success rates.

This is us building nesting sites for European pond turtles in Văcărești. These specific sites are on an east-facing slope, which is favorable for the temperature and incubation of the turtles, and will hopefully boost the hatching success rates. Photo from Caitlyn Ark

In Glyfada, a town just outside of Athens, we visited an aquaculture facility, organic farm, and volunteered at the only turtle rescue center in Greece over our remaining week. This experience culminated in an individual research paper based on an aspect of the Mediterranean diet that interested us and we presented our findings to our peers.

Even though our time abroad was limited to a summer semester, I was able to learn about the cultures in a way that only immersion allows. I loved picking up bits of the language, learning relevant phrases like how to ask for more water (we hiked a lot!), and figuring out that the Romanian word for lynx also means laugh. I admired how the Greeks praise everything as ‘beautiful’, and how their generosity reaches past language barriers. These pieces of culture made this trip significant and irreplaceable. It encouraged my passion and desire to travel and learn through the exchange of ideas. This experience is for wanderers, people who thirst for knowledge, and those who are searching for spontaneous adventures that build memories and cross cultural boundaries.

 

A Close-up Look at the Mysterious Plague Sweeping Through Caribbean Reefs

BOCAS DEL TORO, Panama—Alison Noble’s scuba tank drops over the side of the boat with a deep splash. After pulling on two long white fins and a mask, she follows her tank into the water, fastening the straps and buckles that secure it around her neoprene wetsuit.

Noble checks with her buddy, takes a breath from her regulator, and the two divers descend side-by-side, letting air out of their buoyancy control devices to sink towards the bottom, towards the reef. Noble lays down a long tape measure, known as a transect among scientists, to mark their research area, and starts swimming. She’s looking for a bright white blaze, a malevolent stowaway on the currents that wash over these reefs.

It’s called stony coral tissue loss disease, a plague that’s sweeping down the Caribbean from reefs just off of Miami, Florida.

Noble, a fourth-year marine biology student at Northeastern, is one of 13 students surveying a coral reef off the coast of Panama for signs of the disease as part of the , a year-long intensive marine biology curriculum. She’s surveying the reef in Panama as part of the Biology of Corals class, watching for what could be the newest outbreak of stony coral tissue loss disease.

The Caribbean is the third “sea” of Three Seas. The students also study the Salish Sea from a facility near Seattle, and the Gulf of Maine from Northeastern’s Marine Science Center in Nahant, Massachusetts.

Along her transect, Noble takes note of the species and health of every coral she finds. Corals are made up of hundreds or thousands of small organisms called polyps, which live as a single colony. Each polyp is filled with colorful plankton called zooxanthellae, which photosynthesize and pass food on to their polyp hosts. When a coral dies, it turns a harsh white as it loses its zooxanthellae and reveals its limestone skeleton.

First seen in 2014 but not studied until 2017, stony coral tissue loss disease threatens twenty species that comprise the heart of the Caribbean’s coral reefs. Reefs provide food and beauty to the islands, mainland, and world, attracting tourists and scientists alike.

Using a slate and a pencil to write underwater, Noble marks down a diseased coral: CNAT SCTLD? Translation: Colpophyllia natans, possible stony coral tissue loss disease. Colpophylia natans is the classical ideal of a brain coral, which features winding alleys of polyps separated by peaks and valleys of limestone dressed in vivid greens, yellows, and sometimes, purples—pigments in their resident zooxanthellae that they use to photosynthesize. This coral, however, has been stripped of its regalia, and instead presents swaths of white death.

“Symptoms of SCTLD are highly variable, so it was often difficult to tell whether a colony was affected by SCTLD, another disease, or something else entirely,” says Noble. “Our professors believe that there were cases of SCTLD on the reefs, which was incredibly alarming.”

Though many researchers are trying to find the answer, no one knows what causes the disease. Early studies hint at bacteria, as some researchers have found success in saving some colonies by treating the infections with antibiotics. The first alarm that something was happening to Florida’s reefs was raised by William Precht, an environmental consultant in Florida who has taught coral reef ecology for more than thirty years in the Three Seas program, where he teaches coral reef ecology in partnership with Northeastern associate professor Steve Vollmer. Precht’s research on the cause of the disease is funded by a National Science Foundation grant.

Precht and Vollmer recently attended a meeting in Cozumel, Mexico, once home to some of the healthiest reefs in the Caribbean, now ravaged by stony coral tissue loss disease. In January, Vollmer will be teaching the graduate program of Three Seas, which will continue to monitor the area for new signs of the disease.

“Given the rates of infection and mortality seen in other areas, an outbreak could completely devastate the corals of Bocas,” Noble says. “The reefs that we dove on could be gone a year from now. In a situation like this, it’s really important to hope for the best, but plan for the worst.”

This story was originally published on [email protected] on January 14, 2020

All in the mud: nutrients and microbes aid understanding of marsh resilience

Researchers in the Bowen Lab at Northeastern University’s Marine Science Center are working to expand our understanding of salt marsh resilience to the threats of sea level rise. In recent work, former PhD student Ashley Bulseco, alongside Associate Professor Jennifer Bowen and colleagues, conducted research to better understand how salt marsh environments react to nutrient enrichment and resulting implications for carbon storage in the marsh. Salt marshes are an essential “blue carbon” system, helping to mitigate climate change by trapping significant amounts of carbon. Coastal salt marshes can store more than double the carbon compared to their similar terrestrial counterparts, but it is unclear how human activities are impacting this marsh superpower. Bowen explains that as anthropogenic activities “add nutrients to our coastal waters, those nutrients can have different effects on the sustainability of salt marshes, and it depends on what type of nutrient we’re adding and what the form of nutrient that is (i.e. nitrate, vs nitrite, vs nitrogen).”

Lead author Ashley Bulseco collects samples in a Cape Cod salt marsh.

Lead author Ashley Bulseco collects samples in a Cape Cod salt marsh.

This is not the first time nutrient enrichment studies have been conducted in salt marshes. In 1971, Bowen’s graduate advisor started a salt marsh nutrient enrichment experiment in Cape Cod. Almost 50 years later, the team is still monitoring these plots, Satellite imaging illustrates that the vegetation is remarkably different in fertilized versus control plots. To build deeper understanding of the impacts of fertilization, the Bowen Lab is conducting studies that decipher the effects of different forms of nitrogen. While Bowen’s graduate advisor used nitrogen fertilizer, Bulseco and her team used nitrate specifically to enrich marsh sediment in laboratory experiments, and measured the resulting changes in metabolic activity, and genetic composition of the community of microbes living in the marsh mud.

In their recent study published in Global Change Biology, Bulseco and her colleagues set out to better understand the impact of nitrate enrichment, since nitrogen in coastal waters due to pollution and other factors presents itself primarily in the form of nitrate. There is disagreement in the field about whether nitrate is beneficial or detrimental to the marsh – increasing carbon storage capacity and disrupting marsh stability, or acting as a nutrient and stimulating production. Results of the study indicated that when nitrogen is added in the form of fertilizer, the plants take it up, grow, and thrive. However, nitrate is more available to microbes who get to it before the plants can, stimulating a shift in the microbial community and an increase of microbes responsible for decomposition.

A second publication led by Bulseco, in the journal Limnology and Oceanography, examined how nitrate addition across depths impacts microbial metabolism, and found that regardless of depth, nitrate enhances microbial respiration, with implications for the important role of carbon and nutrient cycling in the marsh.

What’s next in this research? The Bowen lab would like to take this experiment out into the field using a marsh organ, which will help the researchers monitor how interactions between nutrient enrichment and rising sea levels impact marsh carbon storage.

Given the essential ecosystem services provided by salt marshes, particularly their potential for carbon storage and natural nutrient filtration, these studies provide key information that will assist scientists and resource managers prepare for potential impacts of climate change.

As black seabass move north, lobsters face greater predation risk

As ocean temperatures warm, some marine species are moving north which can result in novel species interactions. MSC researchers have found that the northward shifting range of black seabass is introducing new predator-prey dynamics between these fish and juvenile lobsters in the Gulf of Maine.

In the study, lobsters from southern ranges historically overlapping with black seabass hid more and foraged less in the presence of the fish. However, lobsters from further north responded less to the threat of predation from the new and unrecognized predator black seabass.

Northern lobsters that don’t fear predatory bass are therefore more likely to get eaten, with potential implications for the lobster fishery in the Gulf of Marine.

The study was led by Dr. Marissa McMahan, former Grabowski Lab PhD student, and current Fisheries Director at Manomet Fisheries, and results were recently published in the Journal Ecosphere.

The Secret to Better Eyesight? Just Add Oxygen (and Millions of Years of Evolution).

When we look at a painting, its colors and images enter our eyes as waves of light. Thanks to a layer of tissue at the back of our eyes known as the retina, the vibrant yellows and subtle blues of van Gogh’s Starry Night are translated into electrical signals for our brains to interpret.

This remarkable part of our eye is actually an extension of our brain tissue. And just like our brain, the retina needs a lot of oxygen to function properly.

A study published by an international collaboration of researchers recently revealed just how important a steady supply of oxygen was to the evolution of a thicker retina, and therefore better vision.

425 million years ago, the researchers found, your ancestor was a fish with mediocre eyesight. And its sight couldn’t improve until it evolved new ways for oxygen to reach the retina.

“We showed that in the ancestor of most vertebrates, the retina was likely thin and had a relatively poor oxygen supply to it,” says H. William Detrich, a professor of marine and environmental sciences at Northeastern. “As species evolved, when the retina increased in thickness, it was always accompanied by one of several mechanisms that improve retinal oxygen delivery.”

H. William Detrich, a Northeastern professor of marine and environmental sciences. Photo by Matthew Modoono/Northeastern University

The researchers collected information about retinal thicknesses and oxygen delivery mechanisms in 87 vertebrate species around the world and examined the evolutionary links between them. They found that several unique ways had evolved to bring oxygen to the retina, and any vertebrate with good vision exhibited at least one of them.

Around 280 million years ago, when today’s continents were still squished together in a giant land mass we now call Pangea, the first of these changes showed up in fish.

Hemoglobin, the protein in red blood cells that binds with oxygen, mutated in a way that made it extremely sensitive to acid. When the blood became even slightly acidic, the mutated hemoglobin would release a large portion of the oxygen it was holding.

In the layer of the eye right behind the retina, called the choroid, a web of capillaries evolved. This network, known as the rete mirabile (latin for “miracle network,” Detrich says), maintained a slightly acidic environment. When blood passed through it, oxygen was forced out of the hemoglobin to diffuse into the retina at high concentrations.

These changes were accompanied by the evolution of thicker retinas and larger eyes in fish. The influx of oxygen allowed fish eyes to sustain more cells to help them resolve finer details in an image and see better in low light.

While the choroid rete mirabile is still prevalent in fish today, it never evolved in vertebrates on land. These animals instead evolved networks of capillaries within the retina itself, or immediately in front of it, providing oxygen more directly to retinal cells. But this solution was a tradeoff, Detrich says, because the blood vessels could potentially interfere with vision by scattering incoming light.

The researchers found that these mechanisms evolved and vanished from evolutionary history multiple times. Some animals, like the Mexican blind cave fish, adapted to environments where eyesight wasn’t that important, and lost some of the mutations that would bring oxygen to the eye. Ancient mammals evolved more capillaries in and around their retinas when they began being active in the daylight and relying more heavily on vision, about 100 million years ago.

Antarctic icefishes, which Detrich has been studying for decades, were a special case. They lost their red blood cells and hemoglobin in an evolutionary accident, and had to adapt.

“The absence of hemoglobin in the icefishes means that they cannot provide oxygen to the retina using the choroid rete mirabile,” Detrich says. “If those fish were to maintain a decent retinal sickness, another mechanism of oxygen supply had to evolve.”

Detrich was on an expedition in Antarctica when he received an email from Christian Damsgaard, the study’s lead author. Damsgaard wanted to include icefish and several other Antarctic fish species in the study, but didn’t have any high-quality specimens.

“I wrote back and said, ‘Well, I happened to be in Antarctica at the moment. And we can rectify that problem,’” Detrich says.

Detrich and his team collected fresh specimens and blood samples from five species of fish: two icefish species, and three Antarctic species that never lost their red blood.

The researchers found that the icefish species had retinas that were just as thick as those of the other Antarctic species, despite losing their oxygen-carrying hemoglobin. To keep supplying oxygen to their eyes, the icefish had evolved extensive networks of capillaries in front of their retinas.

“It was a particularly informative aspect,” Detrich says.

The odd evolutionary twist of the icefish helps to fill out a larger picture linking a steady supply of oxygen to better vision. Combined with analyses of other vertebrates around the world, it gives us a better fundamental understanding of how our eyes, and the eyes of every other vertebrate, came to be.

“This really advances our state of knowledge about eye evolution,” Detrich says. “Our study is the most comprehensive attempt to synthesize our understanding of the vertebrate eye.”

This story was originally published on [email protected] on December 18, 2019

Karen Aerni

BS, Carnegie Mellon University