WALKERS and anglers are being asked to keep a lookout on stretches of Ashbourne's River Dove after thousands of fish were found dead in one of its tributaries.
The incident, described by one fisherman as "one of the saddest moments in fishing" he had ever seen, is being investigated by the Environment Agency.
Pollution is thought to be the cause of the "destruction of an entire ecosystem" in the River Tean, where fish have been seen lying dead on the river bank, something which is likely to impact on the area for years to come.
The Environment Agency has been on site taking samples and trying to determine the cause of the deaths.
Fisherman Glen Pointon said it was: "One of the saddest moments in fishing I have ever seen.
"A river I often fish called the River Tean, a tributary of the Dove, has been polluted over the last 24 hours and it has killed every single bit of life in the river.
"Thousands of trout fry, grayling, huge trout, stone loach, bullheads are lying in their thousands all over the bed of the river. The Environmental Agency are there now. Gutted is not the word."
A farmer who does not wish to be named said: "It's affected the river immensely.
"Whatever was in there it's killed everything, all the fish from the border of Checkley and Tean all the way down as far as Uttoxeter.
"From small freshwater fish to large brown trouts which have been there for 10 to 15 years, they're all dead.
"We're not sure where it's coming from yet, it hasn't happened to this extent before.
"An entire ecosystem has been destroyed and it will impact for years to come.
"When something like this happens, it ruins a habitat for all wildlife and will have a knock-on effect. For instance the kingfishers will have no food now.
"One of the fishermen who uses the river has said it was a unique habitat that's been destroyed. Some of the fish he was catching there he had never caught anywhere else. Fish are still alive beyond Checkley so it looks like the source of the pollution is further upstream.
"I wouldn't be at all surprised if its industrial waste.
"One of the main problems is the fines to dispose of waste cost so much that it's almost cheaper for people to pay or risk a fine for dumping it in the river."
A spokesman for the Environment Agency said: "We are currently dealing with a fish kill on the River Tean in Staffordshire.
"We are continuing to investigate the cause, checking and taking samples on the river upstream and downstream of where the incident occurred.
"We are still assessing how many fish have died but early estimates are in excess of 1,000.
"We are also appealing to any anglers who are on the Dove downstream to let us know if there is anything out of the ordinary happening.
"Any information can be reported to us on our 24-hour incident hotline 0800 807060."