"It out-competes our native fish" says Dave Mee, from the Environment Agency.
"Water becomes totally dominated by these small fish."
"They're small, they're a nuisance and they're not viable for anglers to fish for, so they're not a targeted species".
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A glorious end to the week, with sunshine which may turn a little hazy later! Temperatures will peak today!
A dry night with incredibly mild temperatures. Setting us up for another lovely day tomorrow!