River’s repopulation is given major head start
5:34pm Tuesday 24th September 2013 in Latest News
WORK has begun to reintroduce wildlife into a section of the River Kennet affected by pesticide pollution earlier in the year.
At the beginning of July, Chlorpyrifos was found in the river, from which Swindon draws much of its water supply, devastating the insect and fresh water shrimp population of the Kennet between Marlborough and Hungerford.
But last Wednesday, a team from Action for the River Kennet (ARK) and Savernake Flyfishers, who fish in Mildenhall, embarked on a project alongside scientists from University College London (UCL) to repair the damage.
The volunteers collected riverfly larvae from three healthy upstream sites of the River Kennet in Marlborough and relocated them to three downstream sites that have been affected by the pollution.
ARK’s director Charlotte Hitchmough said: “It went very well, in total we moved about 140,000 vertebrates.
“The donor sites were monitored very closely before and they will continue to be monitored for the next nine months.
This approach is experimental, usually rivers are left to recover naturally, but this takes years.
“Working with UCL scientists, we are moving invertebrates from healthy reaches to the damaged reaches and then measuring whether they recover faster than those where nature is left to take its course.
“It was volunteers who originally discovered the serious pollution so it’s great that the same people are joining in to help the river’s recovery.”
ARK has carried out riverfly counts throughout August which have already shown an increase in the invertebrate population since the pollution.
As well as regular riverfly monitoring, UCL will be carrying out a number of scientific surveys over the next year, and possibly longer, to see whether the interventions aid the repopulation of these stretches of river.
Action for the River Kennet (ARK) volunteers first saw signs of the chemical spill on July 1 and as of July 21 investigators had still not been able to identify where it entered the water from despite farmers in the area rallying to help.