Sixgill shark mounted with camera/sensor apparatus.
(Credit: Mark Royer/University of Hawaii)
Researchers have mounted cameras and sensors on sharks for new insights into how the apex predators live.
Studying any salt water creature has its difficulties, never mind a deadly predator. But researchers from the University of Tokyo and the University of Hawaii have been able to study sharks in more detail by equipping them with sophisticated cameras and sensors, both attached to the shark and ingested.
The video recorders and sensors are allowing the researchers to see where sharks go, how they get there, how far they travel, and what they do once they reach their destinations. The internal instruments use electrical measurements to track ingestion and digestion of prey, showing when, what, and how much sharks (and other predators, such as tuna) are eating. So far, shark eating habits have mainly been studied in captivity.
So far, the sensors — accelerometers and magnetometers — and cameras have shown the researchers that sharks of different species swim together in schools, interacting with other fish and swimming in repetitive loops across the sea floor. They also found that, rather than simply gliding (as had been previously thought) sharks mainly move through powered swimming, and that deep sea sharks swim in slow-motion compared to other species.
"What we are doing is really trying to fill out the detail of what [the sharks'] role is in the ocean, said Carl Meyer, an assistant researcher at the Hawaii Institute of Marine Biology at the University of Hawaii at Manoa. "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 sharks' position at the top of the ocean food chain makes them important part of the ocean ecosystem, and understanding their behaviour could help both conservation efforts and marine safety.