Special Issue on Methane Published in Limnology and Oceanography

The increase of methane concentrations in the atmosphere, due to both anthropogenic and natural sources, have drawn the attention of scientists in recent years due to the effect  it may have on global climate change. Processes such as climate change and cultural eutrophication may  promote increased emissions to the atmosphere through positive feedback cycles.

The journal of Limnology and Oceanography  recently published the online version of a special issue on methane emissions last month. According to Bob Howarth, Editor-in-Chief of the journal, the aim of this special issue is “to gather together the latest science on compelling topics on methane production and emissions” with the overall goal of “providing a comprehensive view of the state of the science on the role of aquatic ecosystems in the global methane cycle”.


Dr. Leila Hamdan (USM) and Dr. Kimberly Wickland (U. S. Geological Survey) were the Special Editors of the issue. The issue is a compilation of 26 papers covering topics of methane production and emissions from freshwater, estuarine and marine systems and was geared at contributing new knowledge about natural aquatic methane sources, and the forcing factors on emissions in a changing environment.


Dr. Hamdan co-authored the introductory article for the issue.  This was her first publication at USM, and we are excited to share it with you!

Please see the links below:

Link to paper: http://onlinelibrary.wiley.com/doi/10.1002/lno.10449/full

PDF: http://onlinelibrary.wiley.com/store/10.1002/lno.10449/asset/lno10449.pdf?v=1&t=iwy1op6s&s=0e43febfba61b9f4ba7bc4443179af533261ba19

ASLO (Association for the Sciences of Limnology and Oceanography) Website: http://aslo.org/index.php

-Rachel M

Finding Microbes at a Science Fair

Last week, together with four other USM Coastal Sciences graduate students, I had the  opportunity to participate as a judge in the annual Ocean Springs High School science fair. The topics for the projects that these 9th and 10th grade honors biology students chose   spanned biology, chemistry, human health, math and physics, among others. Upon arrival, we were instructed to walk around and score the assortment of tri-fold poster boards that displayed these science projects based on specific requirements such as their format, clarity, and creativity. Although the students were not with their projects, we had the option of calling students out of class to conduct interviews with them, which a few of us did as we came across projects that showed noticeable effort. Our evaluations would be important to these aspiring scientists, as exceptionally well-done projects would proceed to the regional competition at Mississippi State University in February.

The category that immediately grabbed my attention was microbiology. I am a new master’s student in the Hamdan Lab at USM, and have been fascinated by microorganisms since middle school, when I did my own science fair project on the effects of antimicrobial socks. Seeing the turnout for this category was exciting for me, particularly because all of the microbial focused projects fell in the general category of yeast breads. I knew then that I was highly qualified as a judge, as I took a 4-H yeast breads project to the Ohio State Fair during high school in 2010, and competed to win first place in the state. My joint knowledge of microbiology and yeast breads helped me to score and place students in this category. As a result of the judges’ scores, Ms. Tyler Castleman’s project titled, “The Effect of Yeast Starters on Their CO2 Output” took first place and will advance to regionals. I was thoroughly impressed with how this aspiring 10th grader designed her project, documented her results, and communicated her findings with pictures, tables, and graphs. We shared with her a handful of tips learned from our own experiences presenting data, to support her future success; one such suggestion included teaming up with second place winner, Ms. Anna Horton, to compete as a strong team at regionals together.

Ms. Tyler Castleman’s project, 1st place (left) and Ms. Anna Horton’s project, 2nd place (right).

Outreach opportunities are a privilege, and I have discovered that I also enjoy teaming up with other scientists to promote STEM (science, technology, engineering, and math) in our local community. Some of the people that volunteered as judges at this event included research scientists, an engineer, and even a meteorologist! As a woman in science, I take pride in encouraging other young women to participate in science, and to work together. It is important to communicate to these young girls that their intelligence and new perspectives are needed in science, and that they are capable of pursuing a scientific career, as I have. Accordingly, I will be on the lookout for similar outreach opportunities in the near future, so stay tuned!

Rachel M


From left to right: Lennah Shakeri, master’s student; Rachel Mugge, master’s student; Apryle Panyi, PhD student; Division of Coastal Sciences, USM School of Ocean Science and Technology.

Student opportunities available

Title: PhD and MS Graduate Research Assistantships in Marine Microbial Ecology

Location: Division of Coastal Sciences, School of Ocean Science and Technology, University of Southern Mississippi, Ocean Springs, MS


The Hamdan Lab, in the Division of Coastal Sciences at the University of Southern Mississippi seeks exceptional students to participate in marine microbial ecology studies in deep-sea habitats. These funded positions will support independent research on the effects of oil spills on benthic ecosystems in the Gulf of Mexico. Two funded graduate research assistantships will support (stipend, tuition, benefits) highly motivated PhD or MS studies for up to three years beginning in Fall 2017.

Position #1, a student is sought to conduct independent research that investigates microbial population structure, metabolic capability and biodiversity of benthic environments. This position will involve laboratory studies using molecular biological techniques (DNA extraction, amplification, sequencing), bioinformatics, and classical approaches to environmental microbiology (microscopy, metabolic tracers).

Position #2, a student is sought to study sediment biogeochemistry, shipwreck surface properties, and hydrocarbon chemistry. The position will involve laboratory studies in geochemistry, carbon and nutrient and physical property assays.

Both positions: Successful applicants will have a BS or MS degree in biology, ecology, environmental science, chemistry or other relevant fields. Applicants with previous experience in molecular biology, biogeochemistry or statistical analysis are encouraged to apply. Students will be required to participate in the planning and execution of oceanographic research onboard USM’s research vessel Point Sur for periods of up to two weeks at sea. The ability to work collaboratively with students, PIs and external researchers from multiple institutions and fields on interdisciplinary studies of the deep-sea is a must. Those with experience in environmental microbiology or chemistry will be given preferential consideration. Students are expected to participate in development of manuscripts for peer review.

Individuals interested in these positions should contact Dr. Leila Hamdan (leila.hamdan@usm.edu), and provide a cover letter outlining specific interests and experience in the study of marine microbial ecology or biogeochemistry and a curriculum vita. Application for Fall 2017 admission at USM is required.

Please see our websites for more information about USM, the Gulf Coast Research Laboratory, SOST, and studies in the Hamdan lab:






Picture your future here


We are Hiring! Postdoctoral position available immediately

Postdoctoral Research Position in Marine Microbial Ecology available immediately

The Gulf Coast Research Laboratory at the University of Southern Mississippi (gcrl.usm.edu) is seeking a qualified and highly motivated individual for a postdoctoral research scientist position in the laboratory of Dr. Leila Hamdan. The research will be related to the study of marine microbial communities in the deep sea, focusing on the biodiversity surrounding shipwreck ecosystems.

Highly successful candidates would have experience with microbiology and biogeochemistry, with specific knowledge and expertise in molecular biological techniques (DNA extraction, amplification, sequencing). Experience and proficiency in bioinformatics and statistical analysis is highly desired and needed for this position. Applicants must have a Ph.D. in coastal or marine sciences, environmental microbiology or similar field. The main job responsibilities will be data analysis and manuscript preparation. Fieldwork is not a requirement of the position, but opportunities are available to participate in, and design at sea studies in the Gulf of Mexico, onboard USM’s research vessel Point Sur. Excellent written and oral communication skills are needed, as well as a commitment to developing peer-reviewed manuscripts.

The position will be located at the Gulf Coast Research Laboratory in Ocean Springs, MS. Opportunities to collaborate with other research disciplines at GCRL, and within the School of Ocean Science and Technology (SOST) will be available.

The position is offered for 9 months, and may continue for up to 3 years pending funding availability. The position is for immediate hire.

Please see our websites for more information about GCRL, SOST, and studies in the Hamdan lab:





To apply, please submit the following documents via email to leila.hamdan@usm.edu:

  • Cover letter outlining interest and experience in the study of marine microbial ecology
  • Curriculum vitae
  • Contact information for three references

Review of applicants will begin immediately and proceed until the position is filled.

Hamdan lab on the move

A big change has come for the Hamdan Lab.  As of Fall, 2016, the lab has relocated to the University of Southern Mississippi.  We are excited to continue our research on coastal ecosystems at Southern Miss’s Gulf Coast Research Laboratory in Ocean Springs, MS.  More news on the move and our research to follow.

Leila H

Celebrating the Newness on World Oceans Day

Last month, our lab participated in a very successful research cruise on the R/V Pelican. This was my ~27th oceanographic research expedition, and the 7th that I have been Chief Scientist of. The focus of the cruise was mud, glorious, deep-sea mud, which we are using to study the artificial reef effect on benthic microorganisms.

Each cruise is special to me for different reasons. They range from the significance of the discoveries, the technologies, the challenges we overcome, the team work, the food (which was exceptional, thanks to our chef Dave Bhattacharya), etc. This past cruise was special for the newness:

I had the privilege of introducing three Mason students to ocean science (Sarah Brown, class of 2016, Beth Haley, and Matthew Johnson). I shared the challenge and adventure of marine studies with Dr. Joel Gaston (Naval Research Lab), who never envisioned such would be part of his job.  Our Marine Technician, Marah Dahn had her first at bat with multicoring, and with the help of Chief Engineer Rodney Redman, she was a natural, and put core, after core on the deck. Finally, I brought my Department Chair, mentor and friend, Dr. Bob Jonas, an experienced scientist and sailor back out on a UNOLS vessel after a hiatus.

A three day stretch of flat seas was a welcome treat for both science and comfort.  Through the guidance of our Captain, Nicolas Allen, we were always on or ahead of schedule. This provided time to enjoy the show that pods of dolphins were putting on daily.  Every time First Mate Erik Gravel would see a pod, he would alert the science party in seldom subtle ways (“Baby dolphins!”), and then watch the stampede to the bow.  The students asked Erik and I if we ever tire of seeing dolphins ride the bow wake.  We were unanimous: “No, it never gets old“.

On World Oceans Day, I celebrate the newness found in each cruise, my good fortune to have, and share a scientific view of the ocean that most never see, and the wonder of the deep blue that never gets old.

-Leila H

The sights and sounds of the Hamdan Lab students seeing the dolphins for the first time.



Off to sea with colleagues new and old: (left to right) Preston Fulmer, Bob Jonas, Kylara Martin, Joel Gaston.


Mason students and staff (left to right), Sarah Brown, Zeima Kassahun, Beth Haley and Matthew Johnson manage a science selfie with the multicorer and CTD.



We can’t hide our love of the mud. Left to right, Sarah Brown, Beth Haley, Leila Hamdan


…Neither can R/V Pelican crew members Dirk Wakker, Erik Gravel and Christian Williford .


Thanks to all for another great cruise.  The PE16-23 team (left to right): Matthew Johnson, Zeima Kassahun, Bob Jonas, Sarah Brown, Rodney Redman, Beth Haley, Marah Dahn, Dirk Wakker, Kylara Martin, Christian Williford, Leila Hamdan, Nicholas Allen, Preston Fulmer, Joel Gaston, Tom Boyd. Not pictured: Dave Bhattacharya, Erik Gravel, Hernando Bacosa, Kaijun Lu



The Big Picture: Why and How We Study Deep-Sea Shipwrecks

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It’s critical to remember the objective, no matter the task. When working on an ongoing study like GOM-SCHEMA, the main objective could fade into the background when focusing on details. Our goals and objectives are the drivers behind everything we do out here, so why not have them fresh in our minds? Therefore, it’s a good time to step back and look at the big picture to ties all of the moving pieces of a research cruise to the whole study. It does make executing the small (but equally as important) tasks fulfilling.

The goal of GOM-SCHEMA is to better understand and profile the microbial communities associated with historic shipwrecks in the northern Gulf of Mexico. The interactions between these communities and the shipwrecks are ripe for discovery of microbial habitats and unique ecological niches. The  characteristics of the wrecks, specifically the materials they are made of play a role in establishing microbial habitats. To address questions regarding hull materials, we are visiting four 19th or pre-19th century wooden-hull shipwrecks and four WW2 era steel-hulled shipwrecks during the SCHEMA May 2016 cruise.

On top of characterizing microbial communities naturally associated with shipwrecks, we also are investigating the effects of the Deepwater Horizon spill on shipwreck microbial communities.  Through this work, and annual cruises in 2014, 2015 and 2016, we can ask,  if the introduction of hydrocarbons (related to the spill) or chemicals dispersants effect microbial communities on and around the wrecks, and how this may impact the preservation of the wrecks over time.

With these questions in mind, we selected our study sites based on their proximity to spill, the existence of a pre-spill archaeological investigation, water depth, and hull type.

Now that we have touched base with our goals, we can connect new participants in the study to both the big picture, and the intricate details that make up a scientific research cruise.

On this cruise aboard the R/V Pelican, our sample collection utilizes two instrument, a MC800 deep-water multicorer, and a CTD (conductivity, temperature, and depth). The MC800 collects eight (when it works perfectly) replicate sediment cores from depths up to 2000m.  The multicorer has a frame which engages the seafloor, and once that occurs, a weight stand is free to lower the core tubes into the seabed.  When this happens, a lid closes on top of the core tube, creating a vacuum, and an arm swings down to catch the mud from falling out the bottom. As soon as the MC800 is on deck, our team swarms the device and begins logging them, describing them, and preparing them for chemical and biological analyses.
The CTD (conductivity, temperature, and depth) profiles the hydrodynamics of the water column and collects water from any depth of interest using a Niskin bottle.  These, and the hundreds of mud samples from the MC800 are used to profile microbial communities with both molecular biological and biogeochemical analyses.

We are fortunate to collect samples once or twice a year at these sites to help further understanding of the effect of the spill on shipwreck ecosystems, but also to explore a unique microbial habitat in the deep sea.  The time we spend out here is small compared to that in the lab, and the work is hard, but it’s worth it to for the information we create, and to obtain the one of a kind samples we collect.

Only two more days left on the cruise. Stay tuned!

Zeima K