Wearables for sharks: Life-logging misunderstood predators

2014 may be "the year of wearables" but sharks probably won't be Google or Fitbit's next target audience, despite groundbreaking new research by the University of Hawai'i at Mānoa and the University of Tokyo to see exactly what the fearsome predators get up to. While sharks may be well known for inspiring terror in movies like Jaws, scientists actually know relatively little about their underwater lives. Now, thanks to what's described as "flight data recorders for sharks" the researchers have been able to fill in some of the gaps in knowledge.

Sharks of various different species have been targeted by the teams, and fitted with high-accuracy sensor packs. These include high-res tri-axial accerometer-magnetometer data loggers, and compact video cameras, which are strapped to the shark's body.

The result is a "shark's eye" perspective of where the animals swim to, how they move, and what they do along the way. "They allow us to quantify a variety of different things that we haven't been able to quantify before" team member Carl Meyer, assistant researcher at the Hawaii Institute of Marine Biology, explains.

It's already allowed the project to pick out some flawed thinking from what was previously believed about sharks. For instance, marine biologists had thought that the animals used a gliding motion most frequently to swim, whereas the new tracking suggests sharks actually use powered swimming more often. The idea that deep-sea sharks swam in slow-motion compared to their counterparts in shallower water was also disproved.

A range of species have been tagged and tracked, and the team is also using ingestible sensors that can be fed to the sharks or to the prey that sharks usually consume, in order to figure out when and where they feed. The swallowable sensors – similar perhaps to the digital pills Motorola and Google have been working on – use electrical measurements to figure out digestion patterns among other things.