Today (April 20, 2020) marks the 10th year since the Deepwater Horizon oil spill occurred in the Gulf of Mexico. Approximately 5 million barrels of hydrocarbons (oil) spilled into the Gulf for 87 days following the explosion, and since then, DEEPEND (along with several other consortia) have been researching the effects that the oil spill had on the Gulf’s entire ecosystem. Oil reached the seafloor, the open-ocean water column, coastal areas, continental shelf regions, and even was found in marshes and estuaries. “It was an entire Gulf of Mexico-wide event,” Dr. Tracey Sutton said in an interview with Oceana.

Often, people remember the oil that was visible at the surface; however, it’s important to know that 100% of the oil occurred within the water column and affected life throughout the entire ecosystem, especially in the poorly-studied deep pelagic environment ( > 200 m depth) where the Macondo wellhead broke (~1500 m depth).

“As far as we know, the actual impact of the spill is not over yet,” Dr. Tracey Sutton explained in Oceana’s interview.

In another interview with the Independent, Dr. Sutton stated, “In 2017, we were still finding oil contaminants in the eggs [of deep-sea organisms] above levels known to be sublethal for animals. We also saw an overall decline in animal numbers.”

With industry drilling deeper for resources, the risk of another spill occurring increases. Dr. Sutton told the Independent, “another deepwater spill is still very much a real possibility.”

Photo by: U.S. Coast Guard—Reuters/Landov

The DEEPEND Consortium's master’s student/Graduate Research Assistant, Natalie Slayden, was named a GOMRI scholar at the beginning of this year and her work is now featured on the GOMRI website:

“The ocean’s deep-pelagic ecosystem is the largest and least understood habitat on Earth. In the Gulf of Mexico, it was the largest ecosystem affected by the Deepwater Horizon incident. Because there was very limited pre-spill data about deep-pelagic organisms’ biodiversity, abundance, and distribution, it is difficult to determine how oiling may have affected different deep-sea species.

Information about the longevity and age at reproduction of key Gulf of Mexico deep-sea fauna, such as lanternfish or fangtooths, is crucial to determine their vulnerability and resilience to disturbances such as oil spills. However, the depths at which these organisms live and the challenges involved with raising them in captivity or tagging them in the wild make collecting this data difficult.

Natalie Slayden uses ear stones, called otoliths, collected from fish living in Deepwater Horizon-affected waters to study the age and growth of nine Gulf of Mexico deep-sea fish species. Her research can be used to estimate the lifespan and age at which these deep-sea fishes reproduce to determine how quickly a potentially compromised assemblage might be replaced following an environmental disturbance.

Natalie is a master’s student with Nova Southeastern University’s Department of Marine and Environmental Sciences and a GoMRI Scholar with the Deep-Pelagic Nekton Dynamics of the Gulf of Mexico (DEEPEND) Consortium. The GoMRI community embraces bright and dedicated students like Natalie Slayden and their important contributions.

The GoMRI Scholars Program recognizes graduate students whose work focuses on GoMRI-funded projects and builds community for the next generation of ocean science professionals."

Her story can be found here

Congratulations Natalie from the entire DEEPEND team!!

For the second time in NSU history, there were two Provost’s Research and Scholarship Award winners. Nova Southeastern University (NSU) Executive Vice President and Interim Provost Ron Chenail, Ph.D., presented Mariana Morris, Ph.D., and Tracey Sutton, Ph.D each with the 9th Annual Provost’s Research and Scholarship Award.

The purpose of the award is to recognize a faculty member who has demonstrated significant achievement in support of NSU's mission to foster scholarship, intellectual inquiry, and academic excellence. Research and scholarship are two of NSU's eight core values, and excellence in these areas enhances education, patient care, and public service, and develops superior scholarship.

Dr. Sutton's award is a featured story on the GoMRI website

Read the NSU announcement here

Deepesh Tourani

As part of the DEEPEND Consortium, our laboratory has been characterizing the microbial community composition and structure in the northern Gulf of Mexico (NGoM) pelagic waters using modern molecular ecology methods. We had previously sequenced a large cache of 16S rRNA gene data, which included 466 samples from two cruises in 2016 (May: DP03, August: DP04). To enhance taxonomic identifications, Mr. Tourani's MS thesis in Jose Lopez's laboratory at Nova Southeastern University has taken the same baseline 16S data and transformed it to infer the potential  functions of the midwater microbiomes across time and space. The Phylogenetic Investigation of Communities by Reconstruction of Unobserved States (PICRUSt) approach was used for predicting biomolecular function based on the KEGG metabolic database. Strong depth stratification of metabolic function was observed (p<0.001), with a major shift in function between euphotic zone and aphotic zone, associated with a major differential abundance of photosynthetic functional signatures. Temporal analyses showed photosynthetic primary productivity was significantly different across season but not year, which may be attributed to high seasonal outflow of the Mississippi river.