Fish, I guess, are not the smartest fish in the... Well, they're not that smart, let's go with that. Stefano Marras of the Institute for the Marine and Coastal Environment-National Research Council, in Torregrande, Italy, and Maurizio Porfiri of the Polytechnic Institute of New York University have convinced some golden shiners to follow a robotic fish in a schooling pattern.
Watching this video, you get the sense that maybe, just maybe, the real fish is feeling a little bit skeptical about this whole situation. It's definitely in a schooling position a couple points abaft the robot's starboard beam, taking advantage of the wake to reduce drag and swim more efficiently. But, the real fish seems to be making a point of not getting too close, perhaps having a sinking feeling that there's something slightly fishy going on.
It's certainly true that the scale (and the scales) of the robot are a bit off, but apparently the fish are more interested in behavior and body layout. We've seen this sort of thing before, but in the previous research, it was somewhat less clear whether the fish were schooling with the robot, or just using it for cover. In this case, the real fish are clearly interacting with the robot as part of a schooling behavior, which means that it should be possible to have the robot hijack schools of fish completely. Here's what the authors of the study plan to do with this capability:
“If accepted by the animals, robotic fish may act as leaders and drive them away from human-induced ecological disasters that are affecting life in aquatic environments, such as oil spills, and man-made structures, such as dams.”
Not me, though. I can think of better things to do with a robot fish. I'd take it scuba diving with me, and have it convince the prettiest fish to swim over and pose for photos. Then I'd send it out after the tastiest fish, and get them to follow me back to the boat for, uh, more photos. And this, my friends, is what robotics is all about: improving people's lives.