Return to Ixtoc and Mud & Blood: A Summary of C-IMAGE’s Summer Expeditions
– December 10, 2015
(From Fall 2015 Newsletter) Provided by: Ben Prueitt, C-IMAGE Program Assistant
When the planning for the second installment of C-IMAGE was underway in 2013, consortium PIs looked to expand the existing fish and sediment data and gain an encompassing view of the Gulf of Mexico, including the southern extent and the Bay of Campeche. Having a complete record of Gulf fish, sediment cores, and water samples would provide comparable baseline data across the Gulf of Mexico – from the Yucatan to the West Florida Shelf – in the instance of another oil well blowout. It also would allow for a comparison between two Gulf spills, separated by over three decades – the Deepwater Horizon (2010) well blow out and Ixtoc I (1979) spill.
The Center for Integrated Modeling and Analysis of Gulf Ecosystems (C-IMAGE), a GoMRI-funded consortium, studied the first of two regions critical towards achieving a comprehensive Gulf survey during their 2015 field season in the southern Gulf of Mexico. C-IMAGE coordinated and executed three major research cruises this summer, two in the bay of Campeche collecting Ixtoc I sediment cores, water samples, and fish tissues, and one in the northern Gulf continuing Deepwater Horizon studies of sediments and fish, known as the Mud & Blood expeditions. Additionally, consortium partners sampled artificial and natural reefs of the Texas coastline and utilized ROVs and visual surveys for abundance and diversity assessments along the Alabama coast.
Planning the Summer 2015 Cruises:
International collaboration was central to achieving the goals of these expeditions. To prepare for two cruises in the Bay of Campeche, the Universidad Nacional Autónoma de México (UNAM) became a C-IMAGE member to offer their local knowledge and a 164-ft vessel, R/V Justo Sierra, for sediment coring in the southern Gulf. Challenges were expected throughout the summer; most of them came while the research teams were on land. But the science persevered and made great progress in achieving C-IMAGE’s goals.
Planning to take an American ship into Mexican waters for 16 days of fishing came with as much paperwork as one would expect. After clearance to sample within the PEMEX exclusion zone, a 1,165 km2 restricted area in the southern Gulf, plans began to attain special operating permissions for the R/V Weatherbird II. Six months prior, a U.S. State Department application was submitted for the R/V Weatherbird II to enter into Mexican waters, followed by research visas for all cruise members, and finally clearance through Customs & Immigration days before the southern Gulf fish survey got underway.
All the forms were checked and double-checked and three months of coring and fishing was underway.
The total distance traveled by C-IMAGE expeditions in 2015 was 11,151 km, roughly 27% of the earth’s circumference (40,074 km) at the equator.
Out at Sea:
The theme of the first Ixtoc cruise was sediment coring aboard the R/V Justo Sierra in late-July. After a whirlwind Spring of scheduling flights, shipping coring supplies, complying with U.S. and Mexican Customs, obtaining letters of backing from UNAM for U.S. researchers, and planning a rendezvous with Mind Open Media reporter David Levin, an 11-day, 22 person, 8 institution, sediment coring cruise was set. This expedition planned to sample 50 locations (21 critical locations) ranging in depth from 14m to 3,200m, including sites less than 5 kilometers from the original Ixtoc blowout.
The ship left Tuxpan, Mexico on 29 July, several days delayed due to a core shipping delay. The research began immediately with coring just 50km offshore at the first station, SL26A-100. Dr. Patrick Schwing, cruise coordinator and co-Chief Scientist onboard instructed new cruise members on the coring and extruding procedure with help from translators for UNAM researchers.
“The real success story is how well the science party and the Justo Sierra crew functioned as a team,” Schwing said in an expedition summary. “I am grateful for all the hard hours that everyone worked, often waking up before their shift and sometimes working many hours after their shift until all the work was done on deck and in the labs. By the second site, the entire science party had the deck and laboratory operations down to…well…a science,” Schwing continued.
Golden Tilefish burrow holes in bottom sediments creating a home and show significantly higher oil exposure levels than other bottom fish (Snyder et al., 2015). Tilefish were caught in both the northern and southern Gulf this summer, making it possible for a direct comparison of pollutant exposure and possible recovery between the two regions.
The second of the Ixtoc cruises was a three week fishing effort aboard the R/V Weatherbird II from 10 September through 2 October. Onboard this cruise, 13 researchers from four institutions fished at 25 demersal longline stations in the southern Gulf. Each station spanned 5-miles of hooks and enabled our science party to catch fish living near the sea floor to establish baseline database for fisheries throughout the Bay of Campeche, including the PEMEX exclusion zone. The R/V Weatherbird II left St. Petersburg, FL for Progreso, MX where paperwork delays halted the expedition for three days. But a call from Rep. David Jolly (D-FL) freed the ‘Bird (insert Lynyrd Skynyrd lyrics here) and the research team began their fishing with stops in Ciudad de Carmen and Tuxpan, MX.
Dr. Shannon O’Leary, a genomics researcher from Texas A&M University-Corpus Christi (TAMU-CC), was aboard the Weatherbird for the entirety of the trip. “We were all very curious to see what we would get on our first set [in the exclusion zone]. Theory is that if nobody has fished here for so long, we should have more fish, bigger fish and a greater diversity of fish. On the other hand, there is quite a bit of pollution from the well heads and the associated activities of building and maintaining the platforms,” O’Leary said.
This southern Gulf fish survey was followed by a 5 day transit across the Gulf of Mexico from Tuxpan, MX to St. Petersburg, FL collecting plankton, fish larvae, and water samples every 45 km. This long transect resulted in a rich dataset of water quality, plankton population densities and microplastic concentrations along the longest axis of the Gulf.
Between the Justo Sierra sediment cruise and southern Gulf fishing survey, the fifth annual Mud & Blood expedition studied the sediments and fish affected by the Deepwater Horizon and Ixtoc I oil spills. From 15-30 August, the days were filled with fishing and the nights with sediment coring. C-IMAGE researchers sampled sites from previous years to continue data sets from the northern Gulf. Notable findings aboard the Mud & Blood expedition were a record-sized 24.7kg Yellowedge Grouper and a rare Arrownose Dogfish, one of only three ever recorded in the Gulf of Mexico.
C-IMAGE spent 54 days at sea this summer aboard the R/V Justo Sierra and R/V Weatherbird II, sampling sediment cores and fish at 70 and 58 locations, respectively, making it the busiest field season to date for C-IMAGE. Through the challenges faced this summer – delayed shipments, document processing, and a language barrier, C-IMAGE exceeded its ambitious goals for the trip of collecting these baseline samples across the Gulf and studying the 35-year history of Ixtoc.
All of the sediment cores collected during summer 2015 field season will be analyzed in the labs of C-IMAGE partners studying chemical and biological changes within the sediments. Studies will include redox conditions and trace elements (Mn, Fe, Cu, V), sedimentology and geochemistry (14C) (Eckerd College, Florida State University), microbial communities – including oil degrading bacteria (Georgia Tech), foraminfera (USF-College of Marine Science), and volatile organic compounds found in oil like BTEX and phenols (University of Calgary).
The fishing this summer yielded 715 fish from the southern Gulf, and 1,268 fish from the northern Gulf. Target species included Red Snapper, Golden Tilefish, Southern Hake, and Grouper species of which blood, bile, muscle tissue, liver, fin rays, eyes, and otoliths were collected for later analysis. Ongoing C-IMAGE studies are analyzing polycyclic aromatic hydrocarbons (PAH) (USF-College of Marine Science), a toxic derivative of oil, immune responses to oil exposure (USF-College of Marine Science), histological studies (UNAM), and genomic variability across northern and southern regions (TAMU-CC).
The collaboration of C-IMAGE partners studying the sediments and fish of oil spills will not only help understand past spills, but will also help prepare society in the event of another spill. This summer marked a first step towards advancing knowledge of the Gulf by returning to Ixtoc I and establishing baseline data for the region. C-IMAGE will continue sampling sediments and fishes from Mexico to Louisiana in summer 2016.
You can read more about C-IMAGE’s summer cruises, including photo galleries and blog posts, here.