Look out Dai !

That's going to be a big problem, Ziggy. We've got so foreign invasive flora and fauna getting into our natural
systems now. As a freshwater fisherman I can remember wading through the shallows of the River Welland near
Stamford and shooing our natural species of crayfish in great numbers ahead of me. These days all I see is the
american Signal crayfish. They're in our rivers, streams, lakes and ponds and when I catch one it never goes
back!! The Zebra mussel has really knocked Irelands freshwater fishing sideways. It siphons the water for food
really efficiently and has upset set the balance needed for the fish. There must be a commercial use for the Zebra mussel surely??!

 

:DOH: It really is a worry.. strange how so many flora & fauna are being wiped out or taken over so quickly these days... We must now be doing so much damage that it has got to this

 

A lot of it, Marley, is during importation of goods, with unwanted passengers on board,the warming of our
coastal waters, and the introduction of species deliberately. Even freshwater fishing has introduced foreign fish to our waters i.e: Zander, a predatory fish competing with our native pike, the Grass Carp, Catffish, and so on.
The Australians did it with the huge frog brought in from South America to deal with a bug infestation. It had
short legs because of it's origin, but with years it has evolved into a long legged beastie capable of spreading far and wide in the hundreds of thousands!! We certainly are messing up this world!!

 

I first started catching Signal crayfish in Cheshire on a series of lakes that used to be a trout farm. Actually, they were catching me as they were trying to pinch my baits of luncheon meat, sweetcorn, boilies, etc. They're like crabs in that once they grab hold they don't let go, and you're then reeling them in. But some years ago, a friend of mine, who I fish every year with for 2 weeks in Rutland, has a big caravan right alongside the River Nene and we cobbled together a trap. We baited it with left over chicken bits, bits of fish, old spam and we caught 5 on the first go. We've made another 9 traps and have a campaign during the 2 weeks to take as many as we can out of the river. Chub will eat them if they're small enough but they grow pretty fast and they're seem to be everywhere these days.

 

It was a dumb move to introduce it into the UK in, I think, the mid 70's. There was a crayfish plague affecting all the European crayfish back in the 50's and 60's and I believe the Finns and the Swedes brought the Signal crayfish in to make up for the losses of their crayfish. Guess what, not only was it invasive to the extreme but it was also the carrier of the crayfish plague!! Brilliant!, the very experts being employed to protect the European waterways are the one's who didn't have the brains to give the Signal Crayfish a health check. Talk about shooting yourself in the foot!! The Signal crayfish eat the eggs of the fish when they spawn causing another pressure on our stocks and unfortunately they're here to stay.