Fish enlisted to safeguard drinking water supplies

One of the most common types of fish in America has been enlisted in the fight against terrorism. Big cities are using bluegills - also known as sunfish or bream - to safeguard their drinking water.

The fish are being kept in tanks which are constantly replenished with water from the municipal supplies. Sensors work around the clock to register changes in the breathing, heartbeat and swimming patterns of the fish that occur if toxins are present.

Since September 11 the government has taken the threat of attacks on water supplies seriously. San Francisco is to install two more bluegill tanks.

I've caught many blugills in my life. A member of the Sunfish family together with the bass and crappie.