INVESTIGATIONS have so far failed to identify a toxic chemical believed to be responsible for wiping out the entire fish population on a four-mile stretch of river between Withycombe and Blue Anchor. Hundreds of trout died in the incident on the River Pill, which is thought to have been caused possibly by sheep dip or a pesticide. But Environment Agency spokesman Mike Dunning told the Free Press yesterday (Thursday) that initial water samples taken to the EA laboratory at Starcross, near Exeter, for analysis had come back clear. And he said the stretch of river may have to be restocked if it did not re-colonise naturally. The first dead trout were discovered last Sunday afternoon at a holiday park in Blue Anchor. EA officers who were called to the scene found hundreds of casualties as they began their investigations. Officers worked their way up the catchment and concentrated their efforts on the area upstream of Withycombe on the Brendon Hills. Most of the dead fish were between six and eight inches in length and included bullheads as well as trout. Close inspection suggested they had probably been dead for between two and three days. Mr Dunning said the time lapse between the incident and the discovery of the dead fish had made tracing the cause more difficult as the pollutant had largely been washed away. But he said more samples would be carried out on the invertebrate life on the river bed in the hope of gaining more clues. Jim Grundy from the EA said: "Judging from the number of fish killed, we believe it was some kind of toxic chemical. "It must have been pretty nasty because it also wiped out a lot of the invertebrate life in the stream. "In all likelihood, it was probably a pesticide or sheep dip." EA officers will be visiting local farms as part of their investigations and will also continue to monitor the river.
