New DROPPS Researchers at the University of Texas Marine Science Institute
By Lalitha Asirvadam, DROPPS Program Coordinator
The New Year brings new talent to the Dispersion Research on Oil: Physics and Plankton Studies (DROPPS) consortia! Since last fall, DROPPS has added three new post-doctoral researchers and one PhD student to the team at the University of Texas Marine Science Institute (UTMSI). Maud Moison, Tatiana Severin, Charles Tang and Sarah Cosgrove are working with Dr. Ed Buskey and Dr. Deana Erdner on research involving various zooplankton and phytoplankton-bacteria interactions in relation to oil exposure. They each bring a wealth of diverse knowledge to our consortia. Read about their past experiences, research interests and what inspired them to work with DROPPS at UTMSI.
My research interests have focused on marine zooplankton behavior. I am particularly interested in small scale mechanisms that drive individual behavior change under both anthropogenic and climatic forces. For example, My PhD thesis provided a quantitative description of the seasonal change of copepod swimming activity, as well as evaluated the impact of different environmental factors on the copepod behavior.
My research also aims to analyze multiscale ecological responses of plankton communities to external forcing. Specifically, this part of my research involves using adequate methodologies to face the challenge of scale-dependent processes in plankton ecosystem, and the nonlinearity and non-stationarity of time series data.
Within the DROPPS consortium, I am going to study the sublethal effects of low concentrations of crude oil and dispersants on marine zooplankton. More specifically, my current research topics will try to answer to these questions: (1) Does the exposure to PAHs decrease the behavioral adaptations ability of zooplankton and then disturb their migration, feeding or mating activity? (2) Does the exposure to PAHs increase the vulnerability to other stress such UV? (3) What are the long term consequences (i.e. consequences over generations) of a short exposure to PAHs?
Working at UTMSI with Dr. Buskey gives me the opportunity to broaden my experience in individual animal behavior using state of the art optical techniques, while playing an active role in understanding and protecting the marine environment.
I finished my PhD in 2015 at the Oceanological Observatory of Banyuls-sur-mer, France. I worked on the impact of the convection process in the Northwestern Mediterranean Sea on the nutrient budget and the microbial compartment. The nutrient supply driven by the upwelled deep waters during one convection event revealed to be significantly higher than the annual rivers discharges of the Northwestern basin, and was able to sustain the entire spring bloom. Sequencing analyses of the 16S rRNA gene revealed that the bacterial community structure was deeply mixed in the convection cell, with the presence of both surface and deep OTUs from 0 to 1500 m depth. This mixed community persisted after the water column stratification and was entrapped in the new-formed deep waters.
To reinforce my specialization in the ecology of phytoplankton and prokaryotes, I came to UTMSI to work with Dr. Deana Erdner and Dr. Edward Buskey. In DROPPS-II, I aim to understand the impact of oil on the phytoplankton-bacteria interactions. After an oil spill, some phytoplankton species turned out to be resistant, while others were not. The strong interactions existing between bacteria and the host-phytoplankton could be at the origin of this resistance. During my researches in DROPPS-II, I will characterize these interactions and follow the physiological responses of some xenic and axenic phytoplankton strains after an oil exposition.
I graduated from the Chinese University of Hong Kong (CUHK) as a marine ecologist. I decided to pursue a research career in the field of marine plankton. I am impressed by the faculty team at UT Marine Science Institute, as it comprises many well-established research scientists in this field. Particularly, I am interested in the work of Dr. Edward Buskey. The first time I heard about Dr. Buskey was when I came across an article about the interaction between persisting brown-tide alga and planktonic grazers when I was in CUHK. Since my previous research experience is related to the grazing impact of micrograzers on algal blooms, I found the article very insightful. Later, I learned more about Dr. Buskey's work by reading his publications about the effects of dispersant-treated petroleum on marine plankton. I have become interested in how the treated oil affects planktonic organisms and animas up the trophic levels. Therefore, it is my pleasure to take part in the DROPPS research program as a doctoral student. I plan to investigate the effects of crude oil and dispersant on the eco-toxicology, adaptive behavior and population community of marine zooplankton and micrograzers.
I completed my Marine Science degree at The National University of Ireland, Galway along the West Coast of Ireland during the period of 2006 - 2010. It was during my final year when I became increasingly interested in the smaller things in life i.e. plankton! My undergraduate thesis focused on the resting ‘cyst’ stage of dinoflagellate species in an archipelago region located north of Scotland known as the Shetland Isles.
My supervisor Dr. Robin Raine was an incredibly enthusiastic and supportive mentor and I ended up sticking around following the completion of my degree to work in his department as a research assistant. I continued to develop a passion for marine microbiology studies, especially within the area of Harmful Algal Blooms (HABs) and I became part of an on-going monitoring effort along the south coast of Ireland involving the saxitoxin producing species Alexandrium minutum. From here I gained funding for a three year PhD project where my primary objective was to take a closer look at the life history stages of A. minutum and at how both asexual and sexual reproductive phases can impact upon their population dynamics. A. minutum bloom initiation and termination were modeled based on observed variations in environmental parameters and sexual reproductive stages. Aside from the role physiological changes played in A. minutum cell behavior and population dynamics, an attempt was also made to determine the level of control parasitism exerted on the functional ecology of the population. It was after the completion of my PhD that the road to oil studies began. Following my thesis submission, I became employed as post-doctoral researcher as part of a European project called ‘Kill-Spill’. Involving over 30 organizations, the motive of ‘Kill-Spill’ is to develop environmentally and economically viable bio-technological tools to combat marine oil spills. My area of work focused on the eco-toxicology testing of bio-surfactants and plant-derived dispersants.
During the end of this research, I applied for the position of post-doctoral researcher with DROPPS-II and here I am! I’m delighted to be part of the team and under the supervision of Prof. Buskey. I have been following developments and research undertaken regarding the Deepwater Horizon oil spill since its occurrence and feel privileged to be contributing to on-going studies of such importance.
My research while at UTMSI is predominately aimed at utilizing mesocosm experimentation to analyze natural alterations in planktonic community structures following oil pollution events. As all planktonic groups are linked through complex direct and/or indirect interactions, it is important to focus on the long term impacts caused by oil pollution under a variety of environmental parameters. The physiological changes and recovery abilities of various protozoan and phytoplankton species will be assessed over time following the introduction of oil and dispersant to the controlled systems. As both of these groups play crucial roles in the tropic food chain, I will also aim to determine their level of contribution in the bio-transfer of Polycyclic Aromatic Hydrocarbons to higher tropic levels. Overall, the research intends to gain a greater understanding of the interactions between oil droplets and key planktonic organisms by means of mimicking the natural environment.