Tag Archives: marine biology

UGA Skidaway Institute scientists study microbial chemical warfare

In the battlefield of the microbial ocean, scientists have known for some time that certain bacteria can exude chemicals that kill single-cell marine plants, known as phytoplankton. However, the identification of these chemical compounds and the reason why bacteria are producing these lethal compounds has been challenging.

Now, University of Georgia Skidaway Institute of Oceanography scientist Elizabeth Harvey is leading a team of researchers that has received a $904,200 grant from the National Science Foundation to fund a three-year study into the mechanisms that drive bacteria-phytoplankton dynamics.

Researcher Elizabeth Harvey examines a part of her phytoplankton collection.

Understanding these dynamics is important, as phytoplankton are essential contributors to all marine life. Phytoplankton form the base of the marine food chain, and, as plants, produce approximately half of the world’s oxygen.

“Bacteria that interact with phytoplankton and cause their mortality could potentially play a large role in influencing the abundance and distribution of phytoplankton in the world ocean,” Harvey said. “We are interested in understanding this process so we can better predict fisheries health and the general health of the ocean.”

A microscopic view of a population of phytoplankton.

This project is a continuation of research conducted by Harvey and co-team leader Kristen Whalen of Haverford College when they were post-doctoral fellows at Woods Hole Oceanographic Institution. They wanted to understand how one particular bacteria species impacted phytoplankton.

“We added the bacteria to the phytoplankton and the phytoplankton died,” Harvey said. “So we became very interested in finding the mechanism that caused that mortality.”

They identified a particular compound, 2-heptyl-4-quinlone or HHQ, that was killing the phytoplankton. HHQ is well known in the medical field where it is associated with a bacterium that can cause lung infections, but it had not been seen before in the ocean. The team will conduct laboratory experiments to determine the environmental factors driving HHQ production in marine bacteria; establish a mechanism of how the chemical kills phytoplankton; and use field-based experiments to understand how HHQ influences the population dynamics of bacteria and phytoplankton.

“This project has the potential to significantly change our understanding of how bacteria and phytoplankton chemically communicate in the ocean.” Harvey said.

The project will also include a strong education component. The researchers will recruit undergraduate students, with an effort to target recruitment of traditionally under-represented groups, to participate in an intense summer learning experience with research, field-based exercises and some classroom work.

“The idea is for the students to return to their home institutions at the end of the summer, but to continue to work with us on this project,” Harvey said. “This will be a unique opportunity to offer students cross disciplinary training in ecology, chemistry, microbiology, physiology and oceanography.”

In addition to Harvey and Whalen, the research team includes David Rowley of the University of Rhode Island.

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UGA Skidaway Institute develops cutting-edge microbial imaging laboratory

A team of researchers from the University of Georgia Skidaway Institute of Oceanography has received a $226,557 grant from the National Science Foundation to acquire state-of-the-art imaging equipment to investigate microorganisms from the tiniest viruses to larger zooplankton. The equipment will be housed in UGA Skidaway Institute’s new Laboratory for Imaging Microbial Ecology, or LIME.

Researcher Elizabeth Harvey leads the research team that also includes UGA Skidaway Institute scientists Julia Diaz, Marc Frischer, James Nelson and James Sanders.

UGA Skidaway Institute researchers Tina Walters, Marc Frischer and Karrie Bulski practice running zooplankton samples on the FlowCam, a new instrument that is part of LIME

UGA Skidaway Institute researchers Tina Walters, Marc Frischer and Karrie Bulski practice running zooplankton samples on the FlowCam, a new instrument that is part of LIME

The equipment will improve Skidaway Institute’s capability to conduct field and laboratory experiments by automating many viewing methods.

“Anyone who uses a microscope will tell you that it is both tedious and time consuming,” Harvey said. “This equipment will allow us to enumerate and analyze microbes and other planktonic organisms much faster, and will allow us to do more large-scale projects than we could in the past.”

Microscopic phytoplankton photogaphed in the LIME.

Microscopic phytoplankton photogaphed in the LIME.

Much of the equipment will also have imaging capability so researchers will be able to do more detailed measurements on the size and shape of the tiny organisms and how that might relate to the health of an ecosystem.

Marine microbes are an essential component of all marine ecosystems and they play central roles in mediating biogeochemical cycling and food web structure.

“They are the things that drive all other processes in the ocean,” Harvey said. “They play a really important role in the way nutrients, oxygen and carbon are cycled through the ocean. We care a lot about those processes because they impact our climate, fisheries and the ocean’s overall health.”

The benefits of LIME will be shared beyond Skidaway Institute’s science team. Harvey envisions it as a regional center for microbial imaging, available to any other researchers who need the capability.

“Anyone is welcome to come here and get trained to use them,” she said. “They just need to contact me and we can make arrangements.”

Some of the equipment is already in place, while other pieces have not been delivered. Harvey anticipates all the equipment being functional by mid-2017.

Fall black gill cruise rolls out new smartphone app for better data collection

The University of Georgia Skidaway Institute of Oceanography entered the fourth year of its black gill research program with a daylong cruise on board the Research Vessel Savannah and the introduction of a new smartphone app that will allow shrimpers to help scientists collect data on the problem.

Led by UGA scientists Marc Frischer, Richard Lee, Kyle Johnsen and Jeb Byers, the black gill study is being conducted in partnership with UGA Marine Extension and Georgia Sea Grant, and is funded by Georgia Sea Grant.

Black gill is a condition Georgia shrimpers first noticed in the mid-1990s. Many shrimpers have blamed black gill for poor shrimp harvests in recent years, but until Frischer began his study, almost nothing was known about the condition. Now the researchers know black gill is caused by a parasite—a single-cell animal called a ciliate—although the exact type of ciliate is still a mystery.

The October cruise had three goals. The first was simply to collect data and live shrimp for additional experiments.

“We were able to collect enough live shrimp in good shape to set up our next experiment,” Frischer said. “We are planning on running another direct mortality study to investigate the relationship between temperature and black gill mortality. This time, instead of comparing ambient temperature to cooler temperatures as we did last spring and summer, we will investigate the effects of warming.”

Researchers Marc Frischer (UGA Skidaway Institute), Brian Fluech and Lisa Gentit (both UGA Marine Extension and Georgia Sea Grant) examine shrimp for signs of black gill.

Researchers Marc Frischer (UGA Skidaway Institute), Brian Fluech and Lisa Gentit (both UGA Marine Extension and Georgia Sea Grant) examine shrimp for signs of black gill.

If his hypothesis is correct, Frischer believes researchers would expect that raising fall water temperatures to warmer summer levels in a laboratory setting will induce black gill associated mortality in the shrimp caught in the fall.

Those studies will be compared to those that are being conducted in South Carolina in a slightly different manner. Frischer expects the results should be similar.

“However, as it goes with research, we are expecting surprises,” Frischer continued. “We also collected a good set of samples that will contribute to our understanding of the distribution and impact of black gill.”

A second goal was to introduce and begin field testing a new smartphone application developed by Johnsen. The app is intended to be a tool that will allow shrimp boat captains and recreational shrimpers to assist the researchers by filling some of the holes in the data by documenting the extent of black gill throughout the shrimp season. The Georgia Department of Natural Resources conducts surveys of the shrimp population up and down the coast throughout the year. However, those surveys do not provide the researchers with the rich data set they need to really get an accurate assessment of the black gill problem.

A screenshot of the smartphone app for tracking black gill.

A screenshot of the smartphone app for tracking black gill.

“Instead of having just one boat surveying the prevalence of black gill, imagine if we had a dozen, or 50 or a hundred boats all working with us,” Frischer said. “That’s the idea behind this app.”

The fishermen will use the app to document their trawls and report their data to a central database. Using GPS and the camera on their smartphone, they will record the location and images of the shrimp catch, allowing the researchers to see what the shrimpers see. If repeated by many shrimpers throughout the shrimping season, the information would give scientists a much more detailed picture of the prevalence and distribution of black gill.

“The app is complete and available on the app store, but we are still in the testing stages,” Johnsen said. “We want to make sure that it will be robust and as easy to use on a ship as possible before widely deploying it.”

Recruiting, training and coordinating the shrimpers will be the responsibility of UGA Marine Extension and Georgia Sea Grant.

“I think it should be entirely possible to at least have a small group of captains comfortable and ready to start using it when the 2017 season begins,” Frischer said.

Johnsen is excited about the app for what it can provide to the shrimping and research community, but also the implications it has for using apps to involve communities in general.

“There is still work to be done to improve the usability of these systems,” he said. “But I’m confident that we are going to see an increasing number of these ‘citizen science’ applications going forward.”

The final aim of the cruise was to bring together diverse stakeholders, including fishery managers, shrimpers and scientists, to spend the day together and share ideas.

“This was a good venue for promoting cross-talk among the stakeholder groups,” Frischer said. “I had many good conversations and appreciated the opportunity to provide a few more research updates.”

Frischer says he thinks the communication and cooperation among the various stakeholder groups has improved dramatically since the beginning of the study. He recalled that when the study began in 2013, tensions were high. Shrimpers were angry and demanded that something be done to address the problem of black gill. Meanwhile, fishery managers were unclear if black gill was even causing a problem and frustrated that no one could provide them any reliable scientific advice. The research community had not been engaged and given the resources to pursue valid investigations.

“In 2016, we still have black gill. The fishery is still in trouble, but it does feel like we are at least understanding a bit more about the issue,” Frischer said. “Most importantly, it is clear that all of us are now working together.

“My feeling is that the opportunity for us to spend a day like that together helps promote understanding, communication and trust among the shrimpers, managers and researchers.”

Teachers join UGA Skidaway Institute research cruises

JoCasta Green became a teacher after she was told as a child she couldn’t be a scientist because she was a girl. In May, the pre-K teacher from Decatur, Georgia, achieved a small piece of her childhood dream by joining a research cruise on board the University of Georgia Skidaway Institute of Oceanography’s Research Vessel Savannah. Green was one of two teachers on the overnight cruise, some of the first to participate in a cooperative program between UGA Skidaway Institute and Georgia Southern University’s Institute for Interdisciplinary STEM Education (i2STEM).

“Because I am an elementary teacher, I was afraid that maybe I shouldn’t have applied,” Green said. “However, once I got here and everyone was so interested and wanted to share, I really did learn a lot.”

Green (left) learns to set the spring-loaded bottle plugs on a conductivity-temperature-depth sensor array with the help of Natalia Lopez Figueroa from Hampton University.

JoCasta Green (right) learns how to prepare a conductivity-temperature-depth sensor array for deployment with the help of Natalia Lopez Figueroa from Hampton University.

UGA Skidaway Institute scientist Marc Frischer led the cruise with the aim to hunt, collect and study doliolids — a small gelatinous organism of great significance to the ecology and productivity of continental shelf environments around the world. Green and middle school teacher Vicki Albritton of Savannah were the only teachers on board and were able to actively participate in the research activities.

“I think giving any teacher the opportunity come to out to sea is an amazing experience,” Frischer said. “I think it’s transformative, but to have them integrated into the research, we haven’t really done that before.”

Marc Frischer chats with JoCasta Green during the cruise.

Marc Frischer chats with JoCasta Green during the cruise.

Green and Albritton participated in the deck activities. They helped launch the CTD (conductivity-temperature-depth) sensor packages mounted on heavy metal frames and deployed plankton nets that concentrated a wide variety of tiny marine creatures into a small container. The two teachers then worked with the science team in the darkened wet lab to sort through gallons of water and to isolate the doliolids they were seeking.

“I was hoping to see science in action, and I did that all day long,” Albritton said. “I got to participate and learn what was going on and take many pictures, and now I have a wealth of information to take back to the classroom.”

Albritton says an experience like the cruise raises teachers’ credibility in the classroom, because the students see the teachers going out to learn more themselves. “If I want them to be perpetual learners, then I need to demonstrate that same trait,” she said.

Although Green admitted she was nervous about the cruise initially, she credited the scientists with making her comfortable. “They were great teachers,” she said. “I understood what we were doing and why we were doing it.”

Albritton echoed Green’s thoughts and cited the graciousness of everyone she encountered on the cruise. “There wasn’t condescension or an implication that we didn’t know anything,” she said. “There was genuine respect for all of us as professionals in our fields. That was really wonderful.”

A research cruise on the 92-foot R/V Savannah will never be confused with a luxury vacation cruise. Green and Albritton agreed the food was good, but the working spaces were tight and the bunks and cabins even more so.

Green and Albritton were the second group of teachers to join an R/V Savannah research cruise through the partnership with Georgia Southern’s i2STEM program. The goal of the i2STEM program is to improve the teaching and learning of science, technology, engineering and mathematics at all levels from kindergarten through college throughout coastal Georgia.

Vicki Albritton (left) and JoCasta Green

Vicki Albritton (left) and JoCasta Green

The partnership between UGA Skidaway Institute and i2STEM is expected to grow. Five additional doliolid cruises are scheduled this year with space available for as many as four teachers on each cruise. UGA Skidaway Institute will also offer two half-day cruises this month as part of i2STEM’s summer professional development workshop for teachers.

According to Frischer, the ultimate goal of scientific research is to generate and communicate information. “Teachers are some of our most important communicators,” he said. “They communicate to the next generation, so I think it is really special to be able to bring teachers right to where the research is happening. It gives them a total perspective, not only on what we are doing, but how research works and to communicate that to their students.”

Both Green and Albritton said they would encourage their fellow teachers to take advantage of opportunities like this. “You would be crazy not to, in terms of learning and what you can bring back to the kids in your classroom,” Albritton said. “It’s an experience you will never forget.”

Black gill stakeholders meeting set for June 22

As the 2016 Georgia shrimping season gets underway, the University of Georgia Marine Extension and Georgia Sea Grant, and the UGA Skidaway Institute of Oceanography will host a meeting to present the latest research and other information on black gill in Georgia and South Carolina shrimp. The meeting will be held at the UGA Marine Extension Aquarium at the north end of Skidaway Island in Savannah, Ga. on Wednesday, June 22, from 1-4 p.m.

Black gill is a condition affecting the coastal shrimp population. It is caused by a microscopic parasite. Many shrimpers believe black gill may be largely responsible for reduced shrimp harvests in recent years. UGA Skidaway Institute scientist Marc Frischer is leading a research project, now in its third year, into the causes and effects of black gill on the Georgia and South Carolina shrimp population.

A shrimp with the Black Gill condition clearly evident.

A shrimp with the Black Gill condition clearly evident.

The purpose of the meeting is to provide stakeholders, such as shrimpers, fish house owners, wholesalers or anyone else interested in black gill, with an update on black gill research efforts.  Frischer and South Carolina Department of Natural Resources scientist Amy Fowler and will present their latest research findings. UGA Marine Extension and the Georgia Department of Natural Resources will also provide updates. The meeting will be open to the public.

The meeting is for information purposes only. No management decisions will be made.

For additional information, contact Bryan Fluech, UGA Marine Extension, at (912) 264-7269.

What: Black Gill Stakeholders Meeting

When: Wednesday, June 22, 1-4: p.m.

Where: UGA  Aquarium, 30 Ocean Science Circle, Savannah, Ga., 31411

Directions: http://marex.uga.edu/visit_aquarium/