There is little or no evidence to support that Schyzocotyle acheilognathi has significant environmental impacts in the Great Lakes.
Realized:
Historically, S. acheilognathi has had a limited distribution in the Great Lakes infecting several native species including Fathead Minnow (Pimephales promelas), Bluntnose Minnow (P. notatus), and Golden Shiner (Notropis crysoleucas) (Choudhury et al. 2006, Marcogliese 2008).
Potential:
Common Carp (Cyprinus carpio) and Grass Carp (Ctenopharyngodon idella) are principle hosts for Asian tapeworm. However, S. acheilognathi displays a low degree of host specificity (Dove and Fletcher 2000, Maldonado 2003). In 2003, an immature specimen of S. acheilognathi was collected from a White Bass (Morone chrysops) in Lake Winnipeg, Manitoba, Canada (Choudhury et al. 2006).
The Great Lakes native Redfin Shiner (N. umbratilus) has been found harboring this parasite in parts of Nebraska (Choudhury et al. 2006); however, no infections of Asian tapeworm in Redfin Shiner have been realized in the Great Lakes. Redfin Shiner is considered a species of special concern in New York (NYDEC 2012).
Schyzocotyle acheilognathi infects other U.S. species of importance including Roundtail Chub (Gila robusta) (Brouder 1999), the endangered Bonytail Chub (G. elegans) (Hansen et al. 2006), and the endangered Humpback Chub (G. cypha) (Choudhury et al. 2004, Hansen et al. 2006) and is listed as a “Pathogen of Regional Importance” in the southwestern U.S. (USFWS 2012).
Parasitic nutrient competition may lead to reduced body condition and growth, anemia, and temperature-dependent mortality in infected host fish. Pathogenic effects include intestinal inflammation, protein depletion, and altered digestive enzyme activity (Marcogliese 2008). Because of this, infected fish are more susceptible to predation (Lafferty and Morris 1996). However, cascading food web effects have not been reported as a result of S. acheilognathi infection in the Great Lakes.
There is little or no evidence to support that Schyzocotyle acheilognathi has significant socio-economic impacts in the Great Lakes.
Realized:
Tapeworm-parasitized fish are safe to consume, provided the fish are thoroughly cooked, smoked, or pickled (Alexander 2008).
Potential:
Golden Shiner and Fathead Minnow are the most common commercially farmed baitfish in the United States (ODNR 2012).
There is little or no evidence to support that Schyzocotyle acheilognathi has significant beneficial effects in the Great Lakes.
Potential:
Common Carp (Cyprinus carpio) and Grass Carp (Ctenopharyngodon idella) are principal hosts for Asian tapeworm (Dove and Fletcher 2000), infection of which could lead to population reductions in those non-native species.