Robotic turtles used for salmon farm surveillance could help prevent fish escapes. The 'turtle robots' are the first steps in a technology that improves the monitoring of sea cages.

Another, more recent example of fin-based propulsion is the Shoal Consortium's robo-fish, which they hope will lead to autonomous underwater sensor networks.

An autonomous underwater robot called U-CAT, which swims like a turtle and is designed to explore shipwrecks, will be unveiled at the London Science Museum.