Ninth International Crustacean Congress announcement and call for symposia

The 9th International Crustacean Congress (ICC IX) will be held in Washington, DC from 22-25 May 2018, at the Smithsonian Institution and the Renaissance Hotel. This marks the first time this meeting has been in the USA and at the venerable Smithsonian Institution.

The ICC IX Organizing Committee is requesting ideas and leaders for symposia for this important meeting.

Symposia can be half days or full days and can be on any broad topic associated with crustacean biology or related research whether basic or applied. Broad ideas that would include Crustacea combined with other taxa, are welcome. Possible areas for symposia development include genomics/transcriptomics, reproduction, biodiversity, palaeontology, microbiomes, parasites and evolution, invasion biology, aquaculture, fisheries, and so on.

Please communicate symposium ideas to Chris Tudge at ctudge@american.edu.

More information to follow, including important dates and the ICC IX website.

Picture: Famed carcinologist Mary Jane Rathbun in the Smithsonian. Picture from here.

Takahashi and Nagayama, 2016

Takahashi K, Nagayama T. 2016. Shelter preference in the Marmorkrebs (marbled crayfish). Behaviour 153(15): 1913-1930. http://dx.doi.org/10.1163/1568539X-00003399

For many animals, shelters are valuable source to hide from predators. To know acquisition of adequate shelter is important to understand social interactions of animals. Preferences for types of shelter used by the Marmorkrebs (marbled crayfish) were analysed behaviourally. Individual crayfish were presented with a choice between two PVC pipes with four different internal diameters (XL, L, M and S). The time spent in each shelter and the number of times crayfish entered each shelter were measured. Preference ranks of crayfish were XL = L = or > M > S. Our experiments strongly suggested that crayfish chose shelters based first on the diameter of the entrance, and then based on the length of the shelter. Crayfish recognised adequate shelters by visual cues under light conditions and utilised tactile cues from their antennae under dark conditions.

Keywords: recognition • visual cue • crayfish • shelter choice • thigmotactic cue

Vogt, 2016c

Vogt G. 2016. Direct development and posthatching brood care as key features of the evolution of freshwater Decapoda and challenges for conservation. In: Kawai, T. and Cumberlidge, N. (eds.), A Global Overview of the Conservation of Freshwater Decapod Crustaceans, pp. 169-198. Springer International Publishing: Cham. http://dx.doi.org/10.1007/978-3-319-42527-6_6

Abstract

Direct development and posthatching brood care are among the key evolutionary adaptations of decapod crustaceans to life in fresh water. Direct development is obligatory in aeglid anomurans, primary freshwater crabs, and freshwater crayfish. It also occurs in some species of secondary freshwater crabs and freshwater shrimps. Posthatching brood care is the rule in aeglids, primary freshwater crabs, and crayfish, infrequent in secondary freshwater crabs, and rare in freshwater shrimps. Extended brood care is most intense in crayfish where it includes the attachment of hatchlings by a safety line, and specific behaviours of the mother and her offspring. Direct development and posthatching brood care are associated with reduced dispersal and reduced gene flow among populations, which may explain the high degree of endemism and speciation in freshwater decapods. Due to the reduced dispersal and recolonization abilities aeglids, primary freshwater crabs, and crayfish that live in stressed freshwater habitats may face a higher threat of extinction than do species of amphidromous shrimps and crabs that can undergo long-distance migrations.

Keywords: freshwater Decapoda • direct development • posthatching brood care • evolutionary adaptation • speciation • endemism • conservation

Kawai and Crandall, 2016

Kawai T, Crandall KA. 2016. Global diversity and conservation of freshwater crayfish (Crustacea: Decapoda: Astacoidea). In: Kawai T, Cumberlidge N (eds.), A Global Overview of the Conservation of Freshwater Decapod Crustaceans, pp. 65-114. Springer International Publishing: Cham. http://dx.doi.org/10.1007/978-3-319-42527-6_3

Abstract

The number of species in the three families of freshwater crayfish worldwide (Astacidae, Cambaridae, and Parastacidae) are updated by region. These are: Astacidae, western North America (5 species) and Europe (5 species), Cambaridae, eastern North America and Mexico (423 species) and Asia (6 species), and Parastacidae, Oceania (153 species), South America (12 species), and Madagascar (7 species). The conservation status of 611 species of crayfish worldwide is discussed, based on global assessments from the IUCN (International Union for Conservation of Nature) Red List protocols as well as regional assessments on governmental endangered species lists. The current threats to endangered species of crayfish include habitat destruction, water diversion, pollution, and threats from exotic species of crayfish (such as Pacifastacus leniusculus, Procambarus clarkii and Cherax) that have been introduced to other parts of the world where they are having an increasing impact. New threats posed by the parthenogenetic marbled crayfish Procambarus fallax f. virginalis to freshwater ecosystems in Europe and Madagascar are also discussed.

Keywords: alien crayfish • conservation • species diversity • IUCN Red List

2017 Gherardi Prize

The applications for 2017 Francesca Gherardi Memorial Prize are now open. This prize goes to young researchers who study invasive aquatic animals. The application deadline is 30 November 2016.

More information here.

Kotovska and colleagues, 2016

Kotovska G, Khrystenko D, Patoka J, Kouba A. 2016. East European crayfish stocks at risk: arrival of non-indigenous crayfish species. Knowledge and Management of Aquatic Ecosystems 417: 37. http://dx.doi.org/10.1051/kmae/2016024

Abstract

An increasing number of non-indigenous crayfish species (NICS) of apparently pet trade origin have become established particularly in Europe. Especially alarming are recent confirmation of two distantly separated marbled crayfish Procambarus fallax f. virginalis populations in Ukraine and indications of more North American cambarids present in the local pet market. The present study aimed to investigate crayfish species availability within the Ukrainian pet trade together with the climate match and risk they represent to the freshwater ecosystems generally and indigenous crayfish species in particular. Altogether, 15 NICS belonging to all three crayfish families were detected. Considering their origin, availability, probability of establishment, invasiveness and further aspects, marbled crayfish and red swamp crayfish Procambarus clarkii appear to be potentially the most troubling. Available information obtained from the pet trade in ornamental crayfish as a whole demonstrates that the broad availability of NICS most probably overlaps the vast majority of European indigenous crayfish species distribution, including the endemic thick-clawed crayfish Astacus pachypus, which occupies only a limited area that is situated critically close to established marbled crayfish populations. Negative effects of NICS on freshwater ecosystems as a whole can be also expected.

Key words: Ukraine • pet trade • ornamental animal • invasiveness • aquarium

Then we take Berlin

A new article in Verbundjournal reports that Marmorkrebs are establishing themselves in lakes around the German capital of Berlin.

It’s a passing reference in an article by grad student Stefan Linzmaier, who is studying Marmorkrebs as an example of how an invasive species impacts the ecology of a system. I will not claim that I am entirely clear of all the details of Stefan’s ongoing research, since I am reading the article through the help of Google Translate, which can have... interesting interpretations of text.

The map of Marmorkrebs introductions has been updated accordingly. Hat tip to Gerhard Scholtz.

References

Linzmaier S. 2016. Vom Aquarium in den See. Verbundjournal 106: 14-15. http://www.fv-berlin.de/oeffentlichkeitsarbeit/verbundjournal-1/pdfs/verbund106.pdf