2018: A Year in Review

The Coastal Waters Consortium, formed after the 2010 Deepwater Horizon oil spill in the Gulf of Mexico (GOM) and funded by the Gulf of Mexico Research Initiative (GoMRI), is a collection of scientists focused on the impacts of oil residues on coastal and shelf ecosystems. Now in its third round of funding, the CWC team is looking to the future and examining what has been learned.

Dr. Nancy Rabalais records CTD data on a research cruise aboard the R/V/ Pelican. Photo Credit: LUMCON/Logen Benvenuti

CWC research was originally split into five subcategories based on the consortium’s goals and hypotheses: physical/chemical/sedimentary processes, biogeochemistry, invertebrate studies, vertebrate studies, and integrative studies. Individual scientists worked on projects in several categories based on their research specialties. Each project was designed to try and answer one or more of the following research questions:

1. Where is the oil now and how has it changed since 2010?
2. What are its impacts and how have these impacts evolved since 2010?
3. Have parts of the ecosystem been resilient, recovered or compromised?
4. How do the spill-related stressors interact with other stressors?
5. What indicators of stress and recovery can be developed to manage future stressors?
6. What data, tools or perspectives need to be applied or developed to improve our understanding?

These questions have been the foundation for the CWC’s work along the Gulf coast and have helped focus the efforts of each consortium member. As in all scientific inquiry, these original questions may not be fully answered by this team of scientists within this specific time frame. However, the research being conducted is laying the framework for future work and the continued recovery of the Gulf of Mexico.

 

Here is what’s been happening this year:

1. Physical/Chemical/Sedimentary Processes

The Overton lab (LSU) continues to process samples for hydrocarbons (a component of petroleum and natural gas) as they study the fate and movement of carbon following the oil spill. Water and sediment samples are taken regularly from set locations on Bay Jimmy and Barataria Bay in order to check for the presence of oil residue within the ecosystem and “track” its movement. There remain pockets of fresh oil, mostly in crab burrows, but the chemical fingerprint of the original oil is mostly gone.

Marsh sampling in southeast Louisiana. Photo Credit: Coastal Waters Consortium

The Justić/Huang group uses numeric models to analyze, track, and predict the movement of oil, water and sediments based on wind and ocean current patterns. The group has two publications in for review that examine the varying effects of remote and local winds (i.e., large-scale wind systems, like storms, versus small-scale, more regular wind patterns) on water and oil transport. They previously examined the effectiveness of freshwater diversions as a tool for keeping the oil slick away from the coastal habitats.

Dr. Mariotti’s lab continues to develop and test models of marsh shoreline erosion in areas with oil exposure. A related manuscript has been submitted for review. Dr. Mariotti also contributed to the analysis of water and sediment samples that are tested for the presence of hydrocarbons.

1. Biogeochemistry

Dr. Bernhard examined the abundance of comammox bacteria in GOM marsh sediment. Comammox is a microbe that plays a key role in nitrogen cycling by first converting ammonia to nitrite and then nitrite into nitrate. The study demonstrated that this microbe is plentiful in marsh sediment and may help explain the nitrogen cycling rates seen in southeastern Louisiana marshes.

The Roberts lab continues to work their way through a large quantity of samples that will contribute data to several scientific papers. Their studies include habitat preference by periwinkle snails, nutrient cycling in coastal marshes, plant responses to changes in salinity and chemical cycling, and oil’s impact on microbial communities. Early results of the periwinkle study suggest that snails prefer certain grasses over others, dead and aging leaves over live leaves, and that they spend more time on the plants during the day than at night.

Roberts Lab Research Assistant Logan McPherson collects pore water samples from the marsh at LUMCON. Photo Credit: LUMCON/Virginia Schutte

Dr. Giblin conducted a small-scale study of the effects of oil on the nitrogen cycle within New England marshes as a comparison to the studies conducted along the Gulf coast.

The Engel lab continues to process their samples in an ongoing examination of microbial genetics and the impact of oil exposure. These data are being used to monitor the recovery of microbial communities and identify changes in the larger food web.

1. Invertebrate Studies

Dr. Hooper-Bui’s research examines the impact of oil on the insect and spider communities of coastal marshes. Initial reports indicated the insect and spider populations in marshes exposed to oil were not recovering as quickly as populations disturbed by hurricanes. This could indicate that these organisms would be good indicator species of marsh health and recovery.

Collecting insects and spiders in the marsh. Photo Credit: Wakil Bam

1. Vertebrate Studies

The Bird/Rat group of Taylor, Stauffer, and Woltmann worked with Olin, Polito, Husseneder, and Foil to organize a workshop to discuss the group’s food web data and how it will be analyzed. This collaboration brings together research from the Seaside Sparrow and Marsh Rice Rat study with other food web studies from within the consortium. Seaside Sparrows and Marsh Rice Rats have been identified as good indicator species in the marsh because they are year-round residents, easy to capture, and are found in high abundance.

Using mist nets to sample marsh bird populations. Photo Credit: Phillip Stouffer

Dr. Paruk continued the analysis of data from his Common Loon study looking for patterns and trends. Common Loons are another good indicator species as they are long-lived, return to the same feeding and breeding grounds, and are an apex predator within their food web. Paruk’s lab employs catch-and-release procedures to measure PAH levels within the population. PAHs, or polycyclic aromatic hydrocarbons, are carcinogenic compounds that can cause a range of health effects including liver damage, weight loss, immunosuppression, and gut damage. Long-term exposure and accumulation may impact reproduction and survival.

Measuring loon wings. Photo Credit: Earthwatch

Dr. Martin is completing revisions for a manuscript on the feeding preferences of herbivorous invertebrates (grass shrimp and amphipods) on submerged vegetation grown in four concentrations of oil.

A Gulf wide sampling campaign for the group of Roberts, Fodrie, and Martin was cancelled due to Hurricanes Florence and Michael. The group is looking to reschedule for spring 2019.

1. Integrative Studies

Several CWC synthesis activities are moving forward along with several cross-consortia syntheses. These allow for the sharing of data, collaborative analysis, and legacy project creation.

The marsh mesocosm project at the LUMCON Marine Center is in the initial phase of determining baseline conditions. Oiling experiments on the systems will take place in the spring. These mesocosms will integrate aspects of most of CWC’s research over the last seven years.

Mesocosm sampling. Photo Credit LUMCON/Virginia Schutte

 

As we close out on 2018, all GoMRI-supported consortia and researchers are looking ahead to the annual Gulf of Mexico Oil Spill & Ecosystem Science (GoMOSES) Conference in New Orleans in February 2019. This an opportunity for everyone to share their work and discuss the state of the Gulf and the system-wide impacts of the Deepwater Horizon oil spill.

REU Intern Sara Gholson

Our REU interns are back at their respective colleges after a busy summer of independent research here at LUMCON. Over the past ten weeks, they presented a project proposal, designed a scientific study and progressed through the “try-tweak-redo-repeat” process that is the scientific method! Each intern presented his or her research at a student symposium on August 11^th, in Cocodrie.

 

Sara Gholson is a rising senior at Eckerd College in St. Petersburg, FL majoring in marine science. She is an active member of the college’s Marine Science Club that promotes education and volunteer work on campus and in the community. As a Florida native, Sara grew up going to beaches, aquariums and nature reserves and was taught to observe and learn from the world around her. She knew from a young age that she wanted to pursue a future in science because it allowed her to explore, experiment, and ask questions.

Sara assisting the McClain lab with project prep at LUMCON

Sara found the REU program through a simple Google search and was drawn in by the possibility of independent research in any number of new locations. LUMCON’s unique locale in the marshes of southeastern Louisiana was particularly attractive to her. Sara’s research was an offshoot of a larger project led by LUMCON’s Executive Director and faculty member Dr. Craig McClain. Dr. McClain’s lab collected deep-sea samples while on a scientific cruise for his Gulf Wood Fall project (http://craigmcclain.com/?page_id=423) in the Gulf of Mexico earlier this summer. Her project focused on examining the community of macrofauna (small invertebrates that live on or in sediment) within sediment cores taken on the aforementioned cruise. Large numbers of cores were taken within feet of each other and yet there were drastically different populations of organisms in each sediment sample. Sara explained that diversity in sediment grain size and unpredictable additions of nutrients create microhabitats that allow for increased diversity of macrofauna. Although there are still more questions than answers regarding the deep sea, scientists are beginning to understand how and why microhabitats form at depth and what factors contribute to both their longevity and fragility (Google “patch mosaic hypothesis” for more details).

Sara would identify, record, and sketch macrofauna from each sediment core

Sara plans to attend graduate school after her graduation from Eckerd and sees herself pursuing research positions in coastal or deep-sea invertebrates. “I find invertebrates to be fantastic indicators of an ecosystem’s health so I would like to further study their roles in the environment as bio-indicators,” she explained. With these plans in mind, the REU program also provided Sara with opportunities to hone her professional skills as each intern had to develop their own research proposal and then formally present their findings in a scientific symposium setting. Sara believes these skills are just as valuable as the research experience as she begins to think about career paths.

A close up of the invertebrates found within a sediment core

When asked about her favorite aspect of being in Cocodrie, Sara said: “I love how beautiful coastal Louisiana is and how the marsh surrounds the LUMCON facility. I find this area so peaceful and untamed that I believe it’s the perfect area for the most natural marine research possible.”

 

Look for more profiles here and on CWC and LUMCON social media!

REU Intern Ashley McDonald

Our REU interns are back at their respective colleges after a busy summer of independent research here at LUMCON. Over the past ten weeks, they presented a project proposal, designed a scientific study and progressed through the “try-tweak-redo-repeat” process that is the scientific method! Each intern presented his or her research at a student symposium on August 11^th, in Cocodrie.

Ashley McDonald is a rising senior at Eckerd College in St. Petersburg, Florida. She is majoring in marine science with a minor in Italian and is an active member of the college’s Marine Science Club. Growing up in Cuyahoga Falls, Ohio, Ashley strived to learn and understand as much as she could. “I have always wanted to understand how and why things work. Ever since I was in preschool, I wanted to know as much as I could about the world around me and science allows me to do that”.

Ashley (right) and colleague Jordan Logarbo in the field

Ashley learned about the REU program through her mentor at Eckerd and applied to the LUMCON site because of the unique location and possible research topics. “I chose LUMCON because it gave me opportunities that other programs did not. I have become interested in wetlands, restoration, and mangroves and coming to live in the middle of a wetland seemed like a great place to be,” Ashley explained. Her project, under the guidance of Dr. Brian Roberts and his post-doc Dr. Anthony Reitl, examined how Gulf ribbed mussels affect the productivity of marsh cordgrass and the shared soil. From a restoration standpoint, a positive relationship between these two species could be beneficial for the larger ecosystem. Both ribbed mussels and cordgrass are shown to act as soil stabilizers and may prevent, or at least slow down, shoreline erosion. Ashley hopes her time at LUMCON will prepare her for a possible future in research or academia. “I’ve been able to experience theory in my classes, but actually being able to ask and answer questions myself is something else entirely”. She plans to go onto graduate school after finishing at Eckerd in the spring but is still figuring out those details.

Ashley (left) with mentors Dr. Reitl and Dr. Roberts collecting blue mussels in the marsh

When asked about her favorite aspect of being in Cocodrie, Ashley said: “I love watching the sunset on the back deck behind the building. It’s the perfect way to end the day!”

 

Look for more profiles here and on CWC and LUMCON social media!