If the end result is faster discovery of polluted waters, this could be a positive change. Use case scenarios include harbors, oil pipelines and any other underwater environments that need to be tracked for quality.
The fish, which are 1.5 meters (5 feet) long and currently cost 20,000 pounds ($31,600) each, are designed to swim like real fish and are fitted with sensors to pick up pollutants leaking from ships or undersea pipelines.
They swim independently, co-ordinate with each other, and transmit their readings back to a shore station up to a kilometer away.
"Chemical sensors fitted to the fish permit real-time, in-situ analysis, rather than the current method of sample collection and dispatch to a shore based laboratory," said Luke Speller, a scientist at British consultancy BMT Group who led the project.