Instruments strapped onto and ingested by sharks show how the feared but largely misunderstood ocean predators swim, eat and live, U.S. researchers say.
Scientists at the University of Hawaii, working with researchers at the University of Tokyo, have placed sophisticated sensors and video recorders on sharks to record where they travel, how they reach their destinations, and what they do once they get there.
The result is a "shark's eye" view of the ocean and insights into the live of the fish in their natural environment, the researchers said.
"What we are doing is really trying to fill out the detail of what their role is in the ocean," said Carl Meyer, a researcher at the Hawaii Institute of Marine Biology at the University of Hawaii. "It is all about getting a much deeper understanding of sharks' ecological role in the ocean, which is important to the health of the ocean and, by extension, to our own well-being."
The instruments have provided images of sharks of different species swimming in schools, interacting with other fish and moving in repetitive loops across the sea bed.
The researchers discovered sharks used powered swimming more often than a gliding motion to move through the ocean -- contrary to what scientists had previously thought -- and that deep-sea sharks swim in slow motion compared to shallow water species.
"These instrument packages are like flight data recorders for sharks," Meyer said. "They allow us to quantify a variety of different things that we haven't been able to quantify before.
"It has really drawn back the veil on what these animals do and answered some longstanding questions," he said.
The researchers presented their findings Thursday at the 2014 Ocean Sciences Meeting in Honolulu, co-sponsored by the Association for the Sciences of Limnology and Oceanography, The Oceanography Society and the American Geophysical Union.