PE01558: American Signal Crayfish

Unfortunately, there is no evidence to support a proposition that trapping can ever realistically be expected to eradicate a population of signal crayfish. Furthermore, there is no evidence to support a proposition that trapping can be any more effective in controlling American signal crayfish than attempts to control Japanese knotweed by cutting. The untrapped proportion of a population is broadly analogous to the rhizomes of Japanese knotweed, which it is widely accepted no amount of cutting will control. However, trapping of signal crayfish is not a benign activity, trapping activity is very likely to increase the risk that signal crayfish will be spread to new areas, whether accidentally, deliberately, or recklessly. Hence, there is understandably huge concern amongst game fisheries in Scotland regarding any proposal to trap signal crayfish. Scotland will do well to look south of the border. Trapping in England has certainly incentivised a small and ill-informed minority to deliberately introduce signal crayfish to new areas, such as discovered by EA in the lower Lune catchment (Cumbria) in 2013. Removal activity has also increased the likelihood of incidental releases to new areas, whether by deliberate ill-informed release (such as occurred at Ensor's Pool SAC), dumping of unwanted catch (such as found by EA in the upper Lune catchment (Cumbria) in October 2014, or escapes during live transport from trapping sites (such as reported at Redwell Fishery, Cumbria). At present, I'm afraid, the best that we can do is to minimise the risk that signal crayfish will be introduced to new areas. If there is an answer to this problem, it is most likely to be found by research scientists at the molecular level, and there is likely to be a strong case for additional funding of such research in Scotland.

Paul Bradley

11:27 on 18 Feb 2015

There is no scientific evidence that trapping can be used to control or eradicate Signal Crayfish. Such an exercise would be futile and would increase the likelihood of movements of Crayfish to other catchments

James Hunt

9:00 on 17 Feb 2015

I believe we as a country should be pro-active in preserving native species and indigenous eco systems

Christina Fisher

14:27 on 16 Feb 2015

Francis William Carcas - the petitioner is keen for this petition to be considered by the Public Petitions Committee at its meeting in Dumfries on Monday 23 February. Only one signature is required for a petition to be considered by the Committee, there is no required threshold for support. All petitions are considered on their merits and anyone may make a submission to the Committee.

Moderator

10:44 on 16 Feb 2015

It is absolutely ludicrous that the petitioner has been given only 9 days to get signatures on this petition. It smacks of an intention to dismiss the whole subject on the basis that there is insufficient support for the petition. Unless action is taken this problem is only going to get worse. The American Signal Crayfish is an invasive, non-native species and it is important that it should be at least controlled, but at best eradicated. Given enough time to publicise it, I am confident that the signatures would run into the thousands.

Francis William Carcas

13:54 on 14 Feb 2015

American signal crayfish are ruining the tourism in our area which we rely on. Fishing clubs used to come for weeks keeping our local shops hotels going now its all very minimal . Crayfish are a nenace turns a cheap hobby into a very expensive one

Darrel wilson

15:45 on 12 Feb 2015

Although we know we are fighting a losing battle against the signal crayfish if we do nothing we will achieve nothing.

Neil bromilow

17:35 on 11 Feb 2015