Tuesday, January 8, 2013

Sea Surfing “Wave Glider” to Search for Bluefin Tuna and Striped Bass off the North Carolina Coast

The Wave Glider Carey begins her latest mission

A mobile robot called a Wave Glider outfitted with acoustic receivers to detect free-swimming tagged fish was put in the ocean off the coast of Beaufort, North Carolina today. The glider was launched from the Duke ship R/V Susan Hudson outside the Beaufort Inlet by Drs. Dick Barber and Joe Bonaventura of Duke University.  The Glider is part of a collaborative experiment to test the capacity of the unmanned robot designed for biological ocean observation, to detect where animals are in relationship to ocean conditions. For this first test off the North Carolina seaboard, scientists from Stanford, Duke and Eastern Carolina University are working together to listen for tagged bluefin tuna, striped bass and sturgeon that overwinter in North Carolina waters.

Monitoring marine species is valuable not only for the data about their whereabouts but also to better understand our changing oceans and climate. These species can act as roving reporters providing knowledge of their presence or absence in relationship to ocean conditions.  Bluefins and striped bass overwinter in the coastal waters of North Carolina to feed on Menhaden an oily forage fish that is a coastal favorite of both species.

“I am really enthusiastic about the role of the Wave Glider, this new ocean robot, to help us detect where fish are” said Dr. Barbara Block a professor from Stanford University. “We’ve been tagging bluefin tuna for years, through the Tag-A-Giant program, off the Carolina coast and we’re now moving into the phase of developing techniques to long-term monitor their presence or absence along the eastern Seaboard. The glider provides an opportunity to experiment with how to do this in the rough winter conditions of the Hatteras coastline.”

The TAG team tags a giant bluefin
The bluefin tunas Block is searching for were tagged with long-term acoustic tags in Canada this past summer and fall. Block estimates there are over 50 bluefin with tags roaming the Atlantic seas, and is hoping that the hot spot region off Carolina will attract the tagged fish into the region. She and her team have studied bluefin tuna for years determined previously this foraging hot spot is like a favorite restaurant where the tunas tend to gather from several populations roaming in the North Atlantic. By deploying the Wave Glider in this region, they hope to hear the tags’ acoustic pings, which allow them to detect and identify individual tunas.

In addition, ECU professor Roger Rulifson is leading a team on the R/V Cape Hatteras, an NSF ship managed by Duke University, which will be out tagging stripped bass acoustic tags.  “We hope that the Glider can pick up some of the new animals we’re releasing in the next few weeks and help monitor the presence of a variety of fish and sharks we’ve been tagging in the region the past few years,” said Rulifson.  Like Barbara, he is investigating how mobile receivers can aid in the teams capacity to monitor where fish are in the rough winter conditions off the Carolina coast.

Duke University Professor Dick Barber stands with the Carey glider
The glider is was deployed by two of Block’s mentors, Drs. Joe Bonaventura and  Dick Barber from Duke University, where Block got her Ph.D. in 1986. “Ocean Observation is critically important, and I am pleased to see the next steps in biological observation being tested here off North Carolina,” says Professor Dick Barber. “I was fortunate to know Frank Carey, the pioneering tuna scientists from Woods Hole Oceanographic, and a Duke Post-doc, after whom the Carey Glider was named, and he would be very pleased to know of the experimental importance of this mission- chasing Atlantic bluefin and striped bass off our coast”. 

The Wave Glider is manufactured by Liquid Robotics of Sunnyvale California. The project is funded by a Rolex award to Block, The Tag A Giant Fund, Duke University, Stanford University and Liquid Robotics.