Â鶹AV leads research on oil spill's effect on whales

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Almost five years after the massive BP Deepwater Horizon oil spill, researchers are preparing to check on how deepwater marine mammals in the northern Gulf of Mexico are faring.

Dr. Natalia Sidorovskaia, a physics professor at the Â鶹AV, will lead an interdisciplinary consortium of 24 scientists and students that will study the impact of the environmental disaster on endangered sperm whales, beaked whales and dolphins.

It will test monitoring systems to detect, identify and track those populations.

The northern Gulf is familiar territory for Sidorovskaia. She and other researchers conducted passive, underwater acoustic measurements there several times before 2010. They attached recording devices – Environmental Acoustic Recording Systems, or EARS – to the Gulf floor to record sounds made by whales.

The information they captured has helped scientists better understand how whales communicate with each other. It was also used by mathematicians and statisticians to develop models that could estimate current and future sizes of whale populations.

On April 20, 2010, a wellhead on the Deepwater Horizon rig blew out. Millions of barrels of crude oil spewed into the water before the well could be capped 87 days later.

In September 2010, Sidorovskaia and two Â鶹AV mathematics professors, Dr. Azmy Ackleh and Dr. Nabendu Pal, received a $192,000 National Science Foundation Rapid Response grant. The funds enabled them to reinstall six underwater recording devices in pre-spill locations. They then compared that post-spill information with acoustical data gathered in 2001, 2002 and 2007.

Their conclusion: sperm whales preferred to dive for food farther away from the site of the oil spill. “However, beaked whales remained diving close to the disaster site,” Ackleh said. “This perplexing result requires more data to be collected over several years.”

The research group was not able to continue whale monitoring in the area until 2015.

“We would have loved to have had more experiments over this period of time but we didn’t have funding. These experiments are very expensive,” Sidorovskaia said.

In November 2014, she and an interdisciplinary consortium received a three-year, $5.2 million grant from the Gulf of Mexico Research Initiative to continue ecological monitoring and modeling. GoMRI reviewed 47 consortium proposals submitted in 2014; it selected 12 projects for funding.

BP established GoMRI soon after the well blowout. The company ponied up $500 million for studies that examine the impact of oil exploration. An independent board was established to administer the funds.

The ability to compare pre- and post-spill data about marine mammals in the Gulf of Mexico was a key factor in landing the GoMRI funding, according Ackleh, a co-principal investigator and now dean of Â鶹AV’s Ray P. Authement College of Sciences.

“Our group probably has the richest and longest data on marine mammals in the Gulf area,” he said.

The University of New Orleans, University of Southern Mississippi and Â鶹AV are members of the Littoral Acoustic Demonstration Center, created in 2001 to study the impact of Gulf of Mexico industrial operations on deep-diving marine mammals. For the newly funded research project, LADC invited new members to join. It will operate under an expanded name: Littoral Acoustic Demonstration Center – Gulf Ecological Monitoring and Modeling.

Two higher education institutions were added: Oregon State University and Woods Hole Oceanographic Institution.

Five companies joined: C&C Technologies and ASV in Lafayette; Proteus Technologies in Slidell, La.; Seiche Measurements, whose North American office is in Houston; and R2Sonic in Austin, Texas.

This time, Sidorovskaia said, the scientists will try to improve the listening devices and try some new technologies for collecting data. In the past, for example, the  EARS fastened to the floor of the Gulf of Mexico recorded continuously; scientists then retrieved the sounds they captured. Sidorovskaia hopes the EARS technology can be refined to transmit acoustic data to a research laboratory in real time.

Thanks to C&C Technologies, ASV, and Oregon State, the researchers will also have the use of autonomous surface vehicles and underwater gliders. “We are going to compare different approaches to listening to marine mammals,” she said.

The ability to detect and track whales in real time is of particular interest to oil companies because new federal regulations require them to monitor an area for marine mammals before and during seismic exploration surveys they conduct.

The $5.2 million GoMRI grant will also enable the consortium to conduct community outreach to communicate its research findings. The scientists plan to set up interactive displays in the Lafayette Science Museum about ocean exploration and to conduct workshops for high school students on how to build autonomous vehicles.

Ackleh said the ability of researchers, who represent a variety of disciplines, to collaborate on this major project is invaluable. “I’ve come to learn that answering important scientific questions often requires substantial multidisciplinary collaboration.”

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Caption: Scientists deploy underwater listening devices from a Greenpeace ship, the Arctic Sunrise, in September 2010. They were collecting data that would help determine the effect of the BP Deepwater Horizon oil spill on deepwater marine mammals in the Gulf of Mexico. (Photo courtesy of Greenpeace)