Biology researchers voyage to (and under) Gulf of Mexico

Imagine spending eight hours in a space that’s six feet in diameter. With two other people, a thermos and a few PB&J sandwiches. Oh, and you’re about one mile beneath the surface of the Gulf of Mexico. 

That’s the scenario Assistant Professor of Biology Erik Cordes is facing—and relishing—in an upcoming scientific voyage to study how ocean acidification and climate change are affecting deep-sea coral.  The tight quarters belong to Alvin, a U.S. Navy-owned submersible that has helped bring about many insights into deep-sea geology, chemistry and biology.  

“We’ll be looking for corals that show an ability to grow under very harsh conditions,” says Cordes, whose research is funded by the National Science Foundation. “These coral reefs are already more acidic—due to their depth and rise in atmospheric CO2 levels—than any other on earth, yet they survive.”

Cordes and his team will step aboard the research ship Atlantis for a voyage across the Gulf from April 27 to May 16. The team includes Assistant Professor Rob Kulathinal, co-PI on the NSF grant, and Professor Robert Sanders, both from the Biology Department.

“I’m a lab-reared genomicist so these opportunities typically do not present themselves,” says Kulathinal, who will be examining gene expression changes of Lophelia pertusa coral at different levels of acidity. “We will also map the distribution of genetic variation found in other deep-sea corals.”

Sanders, whose research focuses on the microbial food web in oceans and lakes, will be gathering data on organisms that feed on bacteria in surface waters and in the deep chlorophyll maximum, a depth stratum enriched in phytoplankton and other microbes, as well as near oil seeps on the ocean floor. 

Cordes and his team will complete up to 18 dives, gathering coral specimens to conduct experiments at sea and perform genomic analysis back at Temple University. Each dive starts at 6:00AM with a full safety check. Alvin, with its crew of one pilot and two scientists, is lowered into the ocean at 8:00AM. At night the team will use Sentry, an autonomous vehicle, to map and photograph the ocean floor. 

Among the team of 18 researchers, including collaborators from Penn State and Haverford College, all but two have never been on board Alvin before. “It’s exciting to have so many going in the sub for the first time,” says Cordes, who notes Alvin has been fully upgraded since his last voyage in 2010. “I can’t wait to see what they have done.” 

A small film crew will accompany the research team, continuing their Acid Horizon project that chronicles Cordes’ work. In addition to the other collaborators, four graduate students from the Cordes lab, Alanna Durkin, Carlos Gomez, Sam Georgian and Danielle Young, will join the cruise. 

Georgian will examine the coral’s respiration and feeding rates, manipulating CO2 levels to gauge its impact and looking at natural variations of specimens found at different sites. Young, on her third research voyage but her first trip in Alvin, will be studying the effects of the Deepwater Horizon oil spill on two species of soft corals. 

“For most people in our field, getting an Alvin dive is the pinnacle of their careers,” says Georgian. “For graduate students, it’s a rare experience.” 

Cordes’ advice for first-timers: “It’s cold down there, so dress in layers. You will be incredibly busy, but make sure you take a moment to enjoy the feeling of being on the bottom of the ocean.”