Evaluating Invasive Marbled Crayfish as a Potential Livestock for Sustainable Aquaculture

Abstract

The marbled crayfish (Procambarus virginalis) is a recently discovered freshwater crayfish species, which reproduces by apomictic parthenogenesis, resulting in a monoclonal, and all-female population. The animals were widely distributed through the aquarium trade and have established numerous stable wild populations through anthropogenic releases. They are highly prevalent in Madagascar, where they have become a popular source of nutritional protein. As freshwater crayfish aquaculture in open systems is a thriving, but ecologically damaging global industry, alternatives are urgently needed. Although marbled crayfish are often branded by their invasive mode of reproduction, their overall invasiveness is not higher than for other cultured crayfish species. Furthermore, their resiliency and high adaptability provide a strong rationale for evaluating them for closed, and environmentally safe aquaculture approaches. Here we describe a novel population of marbled crayfish in a former German coal mining area that is characterized by acid and polluted water. Even under these adverse conditions, animals grew to sizes, and weights that are comparable to commercially farmed freshwater crayfish. Tailored feed development and laboratory testing demonstrated highly efficient feed conversion, suggesting a considerable capacity for sustainable production in closed systems. We further show that marbled crayfish meat can be readily introduced into European meals. Finally, chemical analysis of marbled crayfish exoskeletons revealed comparably high amounts of chitin, which is a valuable source for the synthesis of chitosan and bioplastics. Our results thus suggest that production of marbled crayfish in closed systems may represent a sustainable alternative for crayfish aquaculture.

Environmental Adaptation of Genetically Uniform Organisms with the Help of Epigenetic Mechanisms—An Insightful Perspective on Ecoepigenetics

“…Significant differences were also found in size-frequency distribution between populations from different bio-climatic regions and habitats in Madagascar and Germany ( Figure 2 G) [ 107 , 108 ]. These water bodies include pristine and polluted rivers, oligotrophic and eutrophic lakes, ponds, rice fields, and cold, warm and acidic waters.…”

“…( A ) Examples of strikingly different marbled crayfish habitats. From Vogt et al [ 104 ], Tönges et al [ 105 , 108 ] and Andriantsoa et al [ 107 ]. ( B ) Genetic differences between representatives from several European populations as determined by whole-genome sequencing.…”

“…( G ) Differences in population structure between pond, pristine mountain river and polluted lowland river in Madagascar and an acidic lake in Germany. Adapted from Andriantsoa et al [ 107 ] and Tönges et al [ 108 ]. ( H ) Principal component analysis of methylation of 122 genes separating four populations from rivers and lakes in Madagascar and Germany.…”

Phenotypic plasticity in the monoclonal marbled crayfish is associated with very low genetic diversity but pronounced epigenetic diversity

“… Examples of strikingly different environments of marbled crayfish including a laboratory setup (A) and pristine, polluted, acidic, cool, and warm natural habitats (B–F) (A and B from Vogt et al 2018 ; C from Tönges et al 2021a ; D and E from Tönges et al 2021b ; F from Andriantsoa et al 2019 ). …”

“…In 2013, we have launched a project at the German Cancer Research Center (DKFZ, Heidelberg) to sequence the marbled crayfish genome and establish a genome-wide methylome at single base resolution, which are important requirements to investigate the relationships between phenotypic plasticity and genetic and epigenetic diversity in depth ( Vogt et al 2015 ; Gatzmann et al 2018 ; Gutekunst et al 2018 ). Since then, many papers have been published on genetics, epigenetic, phenotypic diversity, and environmental acclimatization of the marbled crayfish (e.g., Martin et al 2007 , 2010a , 2016 ; Vogt 2008 , 2018 , 2020a , 2020b , 2022b , 2022c ; Vogt et al 2008 , 2015 , 2018 , 2019 ; Chucholl et al 2012 ; Gatzmann et al 2018 ; Gutekunst et al 2018 ; Lipták et al 2019 ; Andriantsoa et al 2019 ; Linzmaier et al 2020 ; Legrand et al 2021 ; Maiakovska et al 2021 ; Tönges et al 2021a , 2021b ; Veselý et al 2021 ).…”