Cal Poly team puts a tail on a shark

Courtesy photo

A 4-foot robotic water vehicle resembling a torpedo piloted the murky waters off the Long Beach coast this summer tracking a leopard shark with a research team close behind.

The device that a Cal Poly team worked on will help experts conduct less-intrusive shark research, allowing them to chart shark movements from shore and contribute to developing environmental policy.

“We’ll save hundreds of thousands of man-hours that go into collecting information on sharks and gather huge amounts of data from the new technology,” said Chris Lowe, a Long Beach State University shark expert working with the Cal Poly computer engineers.

The autonomous unmanned vehicle follows fish within 100 meters and typically from about 30 meters away.

The new technology has the capability to monitor a shark through acoustic signals sent from tags on the fish.

The tracking method, once it is finished, will be less invasive to ocean species than the current practice of following the tagged sharks around in boats, marine scientists say.

The project’s hope eventually is to monitor the habits of great whites, which swim much faster than leopard sharks.

The scientists want to watch behaviors, including foraging and resting. Then they’ll correlate those habits to ocean temperatures, salinity and visibility.

The Cal Poly project in collaboration with Long Beach State has received a three-year, $490,000 grant from the National Science Foundation’s Robust Intelligence program.

Cal Poly computer science professor Chris Clark and marine biology professor Mark Moline have worked with Lowe to develop the technology. Cal Poly students have participated as well.

“Using this knowledge, fishery experts will be able to make informed decisions regarding conservation and environmental policy,” Clark said.

Christina Forney, a Cal Poly master’s degree student in computer science, worked on the computer code that estimates the shark’s location based on the acoustic signal its tag sends to the unmanned vehicle. Classmate Esfandiar Manii tinkered with the project’s hardware.

The device has hydrophones, or microphones designed to be used underwater, that receive the acoustic signals to identify the shark’s position.

“We were able to track sharks for periods of hours,” Forney said.

Lowe said that his research team will conduct future tests of the vehicle off Malibu and Catalina.

Building a device costs about $80,000, but the program will save money in the long run, researchers say.