Here is one from a few weeks back - they are a nightmare and not a lot you can do to avoid them, they are a complete nightmare and being scavengers will eat most things. If you go down the artificial bait route don't use any flavoured ones as they still like those. Popped up baits they simply walk along the hook link until the bait comes down to them - watched them do it. Avoid any type of tungsten in your set up (tubing, putty etc) as they absolutely love it.
The only way I have found to be able to keep a bait on for more than a short while in waters infested with them is to use shrink tubing over your normal bait or use artificial hook baits with no flavour and avoid the margins. The closer in you fish the more problems you will receive.
Signals have been the ruin of so many waters now even if the chub, perch, carp and catfish have grown well eating the young.
Encourage a few to use traps and thin them down as much as you can. A dead fish (they love mackerel) in the bottom of a net will remove a fair few each night and they taste gorgeous. Make sure they are Signals though and not our indigenous crays.
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