Crayfish help brewery keep water pure

PROTIVIN, Czech Republic - Crayfish equipped with high-tech sensors have been drafted in by a Czech brewery in its quest to keep their water supply pure.

The Protivin brewery in South Bohemia has placed the creatures, which react quickly to changes in their aquatic environment, in fish tanks through which is pumped water from the same natural source that the brewery uses.

The animals are fitted with infrared biosensors which monitor their heartbeat and movement. Data is analyzed by a computer and any changes in the animals' body or behavior flags a change in the purity levels of the water in its tank.