On a European level, a list of invasive alien species of EU concern that cannot be traded, kept, or bred and of which the future dispersal should be limited through preventive actions (e.g. pathway regulation) or active management has recently been approved. Chinese mitten crab and five species of crayfish (O. limosus, O. virilis, P. leniusculus, P. clarkia and Procambarus fallax f. virginalis) are on the list of EU concern and therefore regulated.
I went looking for this approved list. On the European Commission page on invasive alien species, I found some risk assessments, which included Marmorkrebs, here. But nothing seemed to fit the bill of an approved species “blacklist” that is mentioned above.
I will keep looking to see what I can find.
Update, 19 February 2016: Emailing the authors got me a link to this page (in Dutch). And indeed, “invasive crayfish,” including Marmorkrebs, are definitely listed, with an identification sheet to help non-specialists tell the invasive from the natives. I was still curious about the actual legislation, however. It appears to have come into effect 2 January 2016. Using Google translate on this page, I learned:
There is currently a significant difference in policies implemented by the Member States of the European Union, which measures are often too fragmented to lead to effective results. So it makes little sense that one country by conducting a thorough control of some invasive species, if the neighbors do not. To arrive at a more unified and effective approach was therefore defined by the European regulation.
Indeed, the variation in legislation is one part of the problem I’ve written about. But what’s the rule for Marmorkrebs pet owners
There is a total ban on the possession, trade, transport, production and release of these species in the wild. Pet animals which were the entry into force of the Regulation in possession may be held until natural death, provided that the animals are kept in a closed environment, can not escape and can not reproduce. Kind used for the sake of commercial purposes, can be kept for two years after the inclusion of the species on the list under similar conditions.
The “cannot reproduce” clause is... um... problematic for Marmorkrebs owners. They all reproduce! So it’s not clear to me if this means that pet Marmorkrebs people have now are grandfathered in or not. I suspect not.
The penalties will be set by the individual member states.
As the saying goes, “Big if true.” This appears to be a major step towards limiting the spread and ownership of Marmorkrebs in the pet trade in Europe.
This would be a perfect time to start doing research on the availability of crayfish in the pet trade. If the legislation is effective, crayfish availability should decline over the next couple of years. As far as I know, only one paper has tried to systematically examine the effect of legislation on the trade in crayfish: Magalhães and Andrade (2015) found a decrease, but not the elimination, of crayfish in the pet trade, and concluded the ban was not effective.
Boets P, Brosens D, Lock K, Adriaens T, Aelterman B, Mertens J, Goethals PLM. Alience macroinvertebrates in Flanders (Belgium). Aquatic Invasions 11: in press. http://www.aquaticinvasions.net/2015/ACCEPTED/AI_2016_Boets_etal_correctedproof.pdf
Magalhães, A.L.B. and Andrade, R.F. 2015 Has the import ban on non-native red swamp crayfish (Crustacea: Cambaridae) been effective in Brazil? Neotropical Biology and Conservation 10: 48-52. http://dxd.oi.org/10.4013/nbc.2015.101.07
Alien invasive species - European Commission