This week were excused from having to pick our Clever Monkey of the Week from the human performers on the worlds stage, because theyve been outdone by the bluegill sunfish. This clever denizen of just about every pond and lake in America is, we learn, helping to protect the water supplies of major US cities like San Francisco and New York.

It seems the hand-size gamesters, which have delighted centuries of children as easy-to-catch prey, are more sensitive to a wide range of toxins than even the most responsive tech wonder. Theyre also more versatile. A human apparatus can only detect the troublemakers its designed to react to, but to a sunfish a toxin is a toxin.

Said Bill Lawler, one of the founders of a company called Intelligent Automation Corporation, which is the California outfit that markets the bluegill monitoring system, Nature's given us pretty much the most powerful and reliable early warning center out there. There's no known manmade sensor that can do the same job as the bluegill."

The clever little fish began their employment in helping to protect San Francisco's water supply about a month ago.

New York City has been testing its system since 2002 and its DEP reports the fish detected a diesel spill two hours before any of the citys human handiwork. The Big Apple hopes to expand its use of the diminutive security guards.

Although sunfish do have their limits for example, they cant detect germs they still rate as our distinguished Clever Monkey of the Week.