21 September 2012

October Science Café: Marine life after the BP oil spill


TALLAHASSEE, Fla. — Dean Grubbs has been up close with 15-foot tiger sharks — all in the name of science, of course. A marine ecologist and fish expert, his latest project is to study the effects of the 2010 BP Deepwater Horizon oil explosion — which spewed about 210 million gallons of crude into the Gulf of Mexico — on the creatures that live in the deep waters closest to the disaster.

Marine biologist Dean Grubbs. Marine biologist Dean Grubbs will speak at the October 2012 Science Café. The oil explosion killed 11 people, injured 17 others and is reportedly the largest accidental marine oil spill in the history of the petroleum industry.

Grubbs, an associate scholar scientist at the Florida State University Coastal and Marine Laboratory in St. Teresa, will talk about what he and others have discovered at the next MagLab-sponsored Science Café on Oct. 2. The discussion begins at 6:15 p.m. and wraps up at 7:30 p.m. at Ray’s Steel City Saloon, 515 John Knox Road, just across the street from the Tallahassee Mall. Arrive early for a good seat.

“I hope people will come away from my talk realizing that we have this unique ecosystem full of all these crazy, wonderful deep-water species that no one really knows much about,” Grubbs said. “We know less about them than we do about the moon.”

For the last one and a half years, Grubbs has been studying tilefish and hake fish, cutthroat eels, dogfish (a type of small shark), sixgill sharks and gulper sharks. His work is part of the FSU-led Deep-C Consortium, a long-term, interdisciplinary study of the northeastern Gulf of Mexico made possible by a grant from the BP/The Gulf of Mexico Research Initiative. Grubbs and his colleagues are investigating a part of the Gulf called the DeSoto Canyon, a deep, underwater valley off the coast of Pensacola. They want to know what kind of animals live in and around this area at depths that range from 0.1 mile to slightly more than a mile below the surface (200 to 2,000 meters).

They’re also investigating how oil-related toxins, such as polycyclic aromatic hydrocarbons (or PAHs), may be affecting them.

“What we can say at this point is, yes, the closer you get to the oil spill, the more fish are metabolizing the PAHs, but what we are seeing so far is that it’s at a pretty low level,” Grubbs said.

Grubbs and others have caught and examined about 1,500 fish (spanning 52 species) for their ongoing project. Some fish have higher levels of PAHs than others, for reasons that are still unclear. Grubbs and his crew have also found what they think is a new species of skate measuring about 3 feet across.

“That was pretty exciting — and we caught it really close to the Deepwater Horizon site.”

The animals able to live in the cold, dark, deepest waters grow more slowly, Grubbs said.

“The deeper you go, the fewer animals you see that can live down there. The deeper you go, the slower the animal’s metabolism.”

Some deep-water sharks take up to 25 years to fully mature, he added, and some carry their young for two to three years before finally giving birth. To learn more about them, Grubbs catches and tags the fins of big, deep-water sharks with an electronic transmitter, then releases them back into the ocean. The transmitter sends information about the shark back to Grubbs until it pops off.

Learn more about what’s happening to these incredible animals in the Gulf’s deep waters, and the methods Grubbs and others use to study them, at the Oct. 2 café.