22 April 2013

“Your heart stops”: Marmorkrebs in Scotland

Scotsman.com reports on the seizure of Marmorkrebs in the Central Belt.

Dr Colin Bean, science and policy advisor on freshwater biology at Scottish Natural Heritage, formally identified the recovered species in the current case.
He said: “Your heart stops really because American signal are bad enough. The biggest difference between marbled crayfish and other crayfish species is that the others need a male and a female to reproduce, but marbled crayfish are parthenogenic [reproduce asexually] which means you only need one to establish a population.

Yet again, these were Marmorkrebs sold through the pet trade. Kudos to the Scots for taking the task of monitoring exotics seriously:

Anyone caught in possession of non-native crayfish in Scotland can be jailed for up to six months and fined £40,000.

Some species distribution models suggest Scotland could be suitable habitat for Marmorkrebs. At right is an excerpt from Figure 3D in Feria and Faulkes (2011). There are three other models in that figure, and the other three predict much less habitat. Given the number of Marmorkrebs found in Europe since that paper was prepared, though, this version is probably the better reflection of the possible suitable habitat than the others.

Lastly, I appreciate that the news article carries on the European tabloid tradition of referring to small crayfish with monster movie descriptions, calling Marmorkrebs:

A voracious alien predator

Well, most crayfish do catch and eat other animals... but predator? Not what you would usually use to describe an omnivore that eats snails and other small benthic invertebrates.

External link

Scots wildlife at risk from alien crayfish breeds


Feria TP, Faulkes Z. 2011. Forecasting the distribution of Marmorkrebs, a parthenogenetic crayfish with high invasive potential, in Madagascar, Europe, and North America. Aquatic Invasions 6(1): 55-67. http://dx.doi.org/10.3391/ai.2011.6.1.07