'THE river fish have water fleas upon their backs to bite 'em,

Electrocute the fish and the fleas will eat algae ad infinitum.'

So went the theory, anyway, when a team of Environment Agency engineers descended on the River Glyme in Woodstock yesterday to electrocute hundreds of fish.

The reduction of fish numbers will allow the tiny Daphnia water fleas which they feed on to thrive and these, in turn, will feast on the blue-green algae in the river which at the moment is threatening to swamp the ecosystem and kill off the fish.

The electrifying experiment at Woodstock water meadows was organised with help from the Wychwood Project conservation team, who also invited some local primary school children to come and watch.

Project director Sharon Williams explained: "Too much algae in a water body can cause algal blooms and mats that can harm a pond or lake by shading out and preventing other submerged or floating-leaved plants from getting established.

"Algal mats may prevent oxygen mixing into the water, thus lowering available oxygen for invertebrates, fish and other pond life.

"The fish are stunned, netted, put into tanks and transported to an alternative location to be released unharmed."

The Wychwood Project is a registered charity which uses the focus of the Royal hunting Forest of Wychwood to help people to understand and conserve wildlife habitats.

The group works over an area of 120 square miles and 41 parishes mostly in West Oxfordshire.