Procambarus fallax f. virginalis has a moderate probability of establishment if introduced to the Great Lakes (Confidence level: moderate). Marbled crayfish are reported to tolerate a broad range of environmental conditions, including various pH and oxygen levels, and hobbyists report that they can thrive in unfiltered water “straight from the tap” (Robbins, 2018). Their ability to overwinter in the Great Lakes region is unknown, as they have been reported to survive ice cover in laboratory experiments (Souty-Grosset et al., 2006; Feria and Faulkes, 2011) but do best at temperatures between 18-25°C. As omnivores, this species can utilize a diverse range of food sources, and native predators are unlikely to be able to control their rapidly-reproducing populations. Because of their asexual reproduction and high fecundity, once control measures are stopped, the population is likely to return to its former level (Gherardi et al., 2011).
Procambarus fallax f. virginalis has the potential for high environmental impact if introduced to the Great Lakes.
This species’ fast growth rate and r-selected life history traits may allow it to outcompete native species (Jones et al., 2009; Chucholl and Pfeiffer, 2010). This species has been documented to carry rickettsiosis, coccidiosis, and Psorospermium sp., and may be a carrier of the crayfish plague (Souty-Grosset et al., 2006). Closely-related species such as P. clarkii degrade wetlands and increase water turbidity, and while this behavior has not been specifically documented in marbled crayfish, high densities of this species may have significant impacts on ecosystem function and integrity (Chucholl, 2010).
Procambarus fallax f. virginalis has the potential for moderate socio-economic impact if introduced to the Great Lakes.
The marbled crayfish is a burrowing species, and have been reported to damage irrigation systems and dams (Souty-Grosset et al., 2006), particularly in rice paddies, where they may also feed on and injure young plants (Jones et al., 2009; Kawai et al., 2009; Heimer, 2010): similar effects may be possible in wild rice paddies around the Great Lakes. Fishermen in Madagascar also report severe negative impacts on their fishing grounds in the presence of marbled crayfish, but currently all evidence is anecdotal (Jones et al., 2009; Heimer, 2010).
Procambarus fallax f. virginalis has the potential for high beneficial impact if introduced to the Great Lakes.
The marbled crayfish remains a popular pet species in Europe and North America (Chucholl, 2010; Faulkes, 2010), and is also used as fishing bait. The marbled crayfish is a useful laboratory model organism for developmental physiology, epigenetics, and toxicology. Its large numbers of genetically identical offspring, rapid reproductive rate, and simple care requirements make it an ideal species for lab research (Vogt, 2008; 2010). Recent publications document its increasing use as model organism and for cancer research (Jirikowski et al., 2010; Rubach et al., 2011).