American Signal Crayfish

[Marineboy]

We seem to have a problem here. The big american signal crayfish seems to love the conditions it finds in our waterways. It is a big critter, the size of a small lobster - way bigger than the native White Claw crayfish that is rapidly disappearing due to a crayfish disease that the signal carries. Ok, so the signal is a much more impressive creature than the much smaller white claw, but can we permit this invader to continue its invasion?
I have been waiting for several days for an answer from the environment agency for an answer on what we can all do. Can we go out there and start trapping them? I am under the impression that the environment agency are inadvertedly protecting the signal crayfish by making it illegal to catch them. Am I right? Anyone out there in the know? Can we trap these thus reducing numbers, or do we just jump around making noises about what they are doing to our native species? I for one would enjoy a signal cocktail with marie rose sauce. All in the interests of safeguarding our Wild Britain of course.
Do you have signal crayfish in your local waterways? What can we do? What would you like to do?

PS. you can make your own good marie rose sause with equal parts of tomato ketchup and mayonaise.

[galanthus]

There's a sticky on these in the 'water life' forum. Also quite a few threads around, just pop the keywords into the search facility. Welcome to WAB

[Chiltern Chris]

It is not illegal to catch signal crayfish as it is an alien species. It is illegal to put them back if you do catch them. The only license you need is a rod license or a license to use a net e.g. a fyke net.

There are no known methods for wiping out populations of signals. Much research has been done on trapping and pheromone use and a controversial trial of a chemical that kills all invertebrate life in a small river may be undertaken this year in the NW of England in a few months time.

The evidence so far seems to show that trapping in established signal populations makes the problem worse as it prevent the larger crayfish (which are trapped most often) from cannibalising the smaller signals.

The use of fyke nets also has the major problem of causing multiple otter deaths if otter guards are not used. I saw a mother and cub in a single net on Monday and it’s not something I ever want to see again. Therefore, the Environment Agency is loathed to give out lots of fyke net licenses for crayfish trapping when the science indicates that it will both make the problem worse and be a danger to both otters and water voles.

At present the best method of killing signals seems to undertake otter habitat restoration and get a health otter population because otters love them for breakfast, lunch and tea!

Chris

[C C]

They are in their thousands in a small Lake/res near me. They opened the water up for people to go in and trap/net them. One man caught over forty by netting, in about 10 min. He took them home, felt guilty about killing them. Then the fool took them, and released them in to our local river

[Marineboy]

Anyone got any official connections with the environment agency, DEFRA etc? I have my rod licence already. So what stops me trapping them?

Has anyone done underwater research on them?
For example, I had a big lobster in an even bigger fish tank for years in my living room. It was only by close study of this that I gained an insight into exactly how intelligent these animals really are. They have the ability to learn and remember. They deliberately hide and store food. And I have to add that they DO NOT use their serrated claw for cutting up food as most books would have you believe. It is a trap set with a fine hair trigger - this can be heard snap shut from across the room when some poor prawn happens to walk across this trap).
It is only by close study of these animals, (signals) that we have any chance of beating them. So has anyone done any indepth, in the field underwater research into the signal?

[Chiltern Chris]

The “fool” should have been prosecuted. The major problem started when keeping signals was deregulated to reduce "red tape" in about 1994. That meant that the National Rivers Authority couldn't keep tabs on who had them, where they were, whether they were in secure ponds and had no means of prosecuting people who allowed them to escape.

It’s a classic case of ignorant politicians doing something to look good and ignoring the consequences .

[Dan Salter]

Originally Posted by C C

They are in their thousands in a small Lake/res near me. They opened the water up for people to go in and trap/net them. One man caught over forty by netting, in about 10 min. He took them home, felt guilty about killing them. Then the fool took them, and released them in to our local river

God this infuriates me !

The signal problem is a mine field..of pros and cons...re trapping/ not trapping. nearly all these topics have been covered in depth in the multiple threads on WAB about signals and the laws of trapping etc...just do a "search threads" for them