Many big cities are now using bluegills(aka sunfish or bream) to detect toxins in the municipal water supply.
- “Bluegills — a hardy species about the size of a human hand — are considered more versatile. They are highly attuned to chemical disturbances in their environment, and when exposed to toxins, they experience the fish version of coughing, flexing their gills to expel unwanted particles.
The computerized system in use in San Francisco and elsewhere is designed to detect even slight changes in the bluegills’ vital signs and send an e-mail alert when something is wrong.
More than a dozen other cities have ordered the anti-terror apparatus, called the Intelligent Aquatic BioMonitoring System, which was originally developed for the Army and starts at around $45,000.”