Zoobabies, 2021 edition

The Cincinatti Enquirer answers a question I’ve been wondering for a while. 

 

Some years ago, I noted the Cincinatti Zoo had a display of “Marbled crayfish” and listed them as Procambarus fallax. The zoo’s description mentioned nothing about asexual reproduction, so I thought they were slough crayfish from Florida or Georgia.

But a new article about the zoo says:

 

This baby marbled crayfish resembles a small lobster, but it will only grow to 2 to 3 inches long. All marbled crayfish are women. They don't need a partner to reproduce.

 

Marmorkrebs they are, then! Which makes me wonder why their reproduction wasn’t mentioned on the display.

Related posts

 

Zoo babies

 

External links

 

Up close with the Cincinnati Zoo's most adorable ambassadors

International Conference on Aquatic Invasive Species 2022

The date for the next conference on aquatic invasive species will be 18-22 April 2022 in Belgium. It will be a mix of in person and online and the focus will be on climate change. But I’m sure there will be some crayfish content!

 

It must be challenging to plan conferences, since COVID-19 is still out of control in some regions but maybe coming under control with vaccination and we really don’t know what will happen.

External links

 

22nd International Conference on Aquatic Invasive Species

Ontario seeks public comment on regulating marbled crayfish

Nation Valley News reports that Ontario is moving to the next phase of a process that could result in the regulation of Marmorkrebs in the province, along with twelve other aquatic species.

 

The first round of consultation identified “no significant concerns” of regulating Marmorkrebs.

 

A ban on Marmorkrebs in Ontario would arguably be the most significant regulatory action in North America yet implemented. Ontario is Canada’s most populous province. It’s also one of the largest single jurisdictions in terms of size in North America. Currently, Marmorkrebs are routinely available in the pet trade.

Louisiana red swamp crayfish (Procambarus clarkii) are also on the list. This crayfish would get an exception for its use as food.

Comment is open until 7 June 2021.

External links

 

Regulating 13 invasive species and watercraft as a carrier of invasive species under Ontario’s Invasive Species Act, 2015

 

Seeking information on invasive species and carriers under the Ontario Invasive Species Act, 2015 (closed)

 

Province seeks input into wild pig strategy and updates to Invasive Species Act

 

Scheers and colleagues 2021

Scheers K, Brys R, Abeel T, Halfmaerten D, Neyrinck S, Adriaens T. 2021. The invasive parthenogenetic marbled crayfish Procambarus virginalis Lyko, 2017 gets foothold in Belgium. BioInvasions Records 10(2): 326-340. https://doi.org/10.3391/bir.2021.10.2.11

 

Abstract

 

In 2020, four populations of the marbled crayfish Procambarus virginalis, which is included on the list of Invasive Alien Species of Union concern, were discovered in northern Belgium. These records represent the first established populations of this invasive parthenogenetic species in the Benelux. The marbled crayfish seems well established at all sites where it was discovered. Genetic analysis confirmed the species’ identity with the obtained COI Folmer fragments being 100 percent identical to reference sequences of P. virginalis from Germany, Italy, Sweden and the Czech Republic. We proposed a single diagnostic nucleotide for unambiguous character-based species identification between P. virginalis and P. fallax. The finding of this new species through opportunistic surveys instigated by citizen science reports indicates considerable knowledge gaps on crayfish distribution in Belgium. Considering the regulated status of most species in Belgium, we advocated the further set-up of dedicated crayfish surveillance using passive and active monitoring including environmental DNA detection.

 

Keywords: invasive species, Cambaridae, non-native species, Procambarus fallax forma virginalis

Stara and colleagues 2021

Stara A, Zuskova E, Vesely L, Kouba A, Velisek J. 2021. Single and combined effects of thiacloprid concentration, exposure duration, and water temperature on marbled crayfish Procambarus virginalis. Chemosphere 273: 128463. https://doi.org/10.1016/j.chemosphere.2020.128463

Abstract

The increasing utilization of chemicals and ongoing climate change have a negative impact on aquatic ecosystems. The present study examined combined effects of water temperature, chemical concentration, and duration of exposure to the neonicotinoid thiacloprid on marbled crayfish Procambarus virginalis. Crayfish were exposed to thiacloprid at the environmental concentration of 4.50 μg L^-1 and 10% 96LC50 to marbled crayfish, 64.64 μg L^-1, at water temperature of 17 and 23°C for 28 days followed by a 28 day depuration period. No crayfish died during the experiment. Both thiacloprid concentrations at 23°C showed a synergistic effect with temperature on the biochemical indicators in haemolymph compared to those at 17°C. Both concentrations of thiacloprid at both temperatures were associated with significant differences from thiacloprid-free controls (P < 0.01) in haemolymph glucose, ammonia, calcium, inorganic phosphate, and lactate; haemolymph enzymes aspartate aminotransferase, alanine aminotransferase, creatine kinase, and alkaline phosphatase; antioxidant biomarkers superoxide dismutase, catalase, glutathione S-transferase, and reduced glutathione in hepatopancreas, muscle, and gill, and showed lipid peroxidation in hepatopancreas and muscle. Histological analyses revealed structural changes and damage to gill and hepatopancreas of exposed crayfish.

Keywords: neonicotinoid • insecticide • non-target organism • synergism • haemolymph • antioxidants

Grandjean and colleagues 2021

Grandjean F, Collas M, Uriarte M, Rousset M. 2021. First record of a marbled crayfish Procambarus virginalis (Lyko, 2017) population in France. BioInvasions Records 10(2): 341-347. https://doi.org/10.3391/bir.2021.10.2.12

 

Abstract

 

Here we report the first record of marbled crayfish Procambarus virginalis in France. In total, 34 individuals were found in a pond close to the Moselle River, coexisting with the invasive Faxonius limosus and the native Astacus astacus. Their presence seems limited to one pond of the seven located in this area, probably due to a very recent human introduction. Molecular analyses based on COI mt gene confirmed the morphological identification of captured specimens as marbled crayfish. The risk of spread to the Moselle is very high particularly during flood periods. Management recommendations are given. 

 

Keywords: invasive species • parthenogenetic crayfish • coexisting crayfish species • mitochondrial DNA

Ohio lists Marmorkrebs as “Injurious aquatic invasive species”

Ohio is the latest North American jurisdiction to regulate Marmorkrebs.

 

In a PDF dated 9 April 2021 in the file name, Marmorkrebs is designated an Injurious Aquatic Invasive Species (IAIS). The one page pamphlet notes:

 

Listed species are unlawful to possess, import, or sell unless dead and/or preserved.

However, the Department of Natural Resources list of injurious aquatic invasive species is on a page that says “Published on Jul 31, 2020” in the search results. So it’s possible that Marmorkrebs were already listed last year and the new document is just the start of publicizing the new regulation. Another PDF from Spring 2019 indicates that Ohio was planning to add marbled crayfish to the list. But it hadn’t happened yet.

It’s symptomatic of a recurring problem. I, as someone who actually cares about when new regulations about this species are passed, cannot find out when these things happen. What chance does a normal pet owner with a 10 gallon aquarium have?

External links

 

Marbled Crayfish (Marmorkrebs) Control in Ohio (PDF)

Injurious Aquatic Invasive Species

 

New website: The Perfect Invader

The Perfect Invader is a new project to examine how the introduction of Marmorkrebs in Madagascar is affecting human health. 

 

Part of the project is looking at how people are eating Marmorkrebs. Some of that has already been published (e.g., here and here).

 

A newer aspect of the project, which I’ve seen in relation to other crayfish, but not Marmorkrebs, is how the crayfish affect schistosomiasis infections.

 

Check it out!

 

External links

 

The Perfect Invader