17 September 2013

Plague poster

From Kärntner Institut für Seenforschung (roughly translated, the Carinthian Institute for Lake Research) comes this poster on whether Marmorkrebs can spread the dreaded crayfish plague (click to enlarge):


The short answer is yes, as predicted. Although they can carry it, there are still no reports of Marmorkrebs in the wild carrying crayfish plague that I know of.

This poster was presented at the 16th International Conference on Diseases of Fish and Shellfish. This meeting had a large symposium on crayfish plague.

External links

Kärntner Institut für Seenforschung
16th International Conference on Diseases of Fish and Shellfish

10 September 2013

Turning the tide

Marmorkrebs are a concern as an emerging invasive crayfish, but in much of the world, they still have a long way to go before they catch up with other exotic crayfish. In North American, a lot of attention has revolved around the rusty crayfish, Orconectes rusticus.

This article describes an effort to control rusty crayfish in a semi-natural setting that seemed to have worked. The abstract reports that they reduced the number of crayfish by 99% of where they started. The paper goes on to look at what happens to the lake when the crayfish are gone. As I’ve often said to people, “A lake with crayfish looks completely different than one without crayfish,” and this research bears that out.

How did the team get this invasive crayfish under control? Trapping, and a lot of elbow grease (my emphasis).

Hansen thinks that, if the right agency or lake association had the time and money to pay someone to extensively trap crayfish, it could work. But, she cautions, it’s a lot of work. Her group needed eight summers of full-time trapping to finally get rusty crayfish numbers where they wanted them.

Reference

Hansen GJA, Hein CL, Roth BM, Vander Zanden MJ, Gaeta JW, Latzka AW, Carpenter SR. 2013. Food web consequences of long-term invasive crayfish control. Canadian Journal of Fisheries and Aquatic Sciences 70:1109-1122. http://dx.doi.org/10.1139/cjfas-2012-0460

External links

In whole-lake experiment, have invasive crayfish met their match?

01 September 2013

Janský and Mutkovič, 2010

Janský V, Mutkovič A. 2010. Rak Procambarus sp. (Crustacea: Decapoda: Cambaridae) – prvý nález na slovensku. Acta Rerum Naturalium Musei Nationalis Slovaci 56: 64-67.

Abstract

Marbled crayfish – Procambarus sp. (Crustacea: Decapoda: Cambaridae) – first find in Slovakia. The species was found in gravelpit near-by the village Koplotovce, in May 2010. Distribution of this species in Europe and its risk for our nature is discused (sic).

Keywords: marbled crayfish • distribution • Slovakia

Note: Paper in Slovak.