Tetracotyle diminuta

Summary of species impacts derived from literature review. Click on an icon to find out more...

Environmental	Socioeconomic	Beneficial

Ichthyocotylurus pileatus has a high environmental impact in the Great Lakes.
Realized:
In the Great Lakes, larval or immature I. pileatus have been detected in Yellow Perch (P. flavescens) at 37.7% prevalence (582 fish examined) with light (1-9 parasites/host) to moderate (10-49 parasites/host) infections (Dechtiar and Christie 1988, Dechtiar and Lawrie 1988, Dechtiar and Nepszy 1988); Walleye (S. vitreus) at 47% prevalence (15 fish examined) with moderate infections (Dechtiar and Lawrie 1988); and Trout-Perch (P. omiscomaycus) at 46.5% prevalence (>39 fish examined) with light infections (Bangham and Hunter 1939, Dechtiar and Christie 1988). The larval form of I. pileatus has also been found in piscivorous birds of Lake Superior and the Lake St. Clair system (Muzzall and Whelan 2011).

Potential:
In general, digenean flukes can cause pathological effects and mortality in juvenile and adult fishes (Bychovaskaya-Pavlovskaya and Petrushevski 1963, Dukes 1975). While not documented for this species in the Great Lakes, adult digenean parasites tend not to severely impact their definitive host; infection of first and second hosts may result in castration (due to invasion of host gonads) and decreased fitness (due to diversion of host energy to parasite nutrition), respectively (Bartoli and Boudouresque 2007). Because of altered behavior, infected fish may be more susceptible to predation (Lafferty and Morris 1996). Cascading food web effects have not been reported as a result of I. pileatus infection in the Great Lakes; however, I. pileatus still has the potential to be pathogenic to fish, particularly young individuals, when intensities of larvae/immature parasites are high (Muzzall and Whelan 2011).

There is little or no evidence to support that Ichthyocotylurus pileatus has significant socio-economic impacts in the Great Lakes.
Potential:
Recreationally valuable Great Lakes species susceptible to I. pileatus infections include Yellow Perch, Walleye, and Trout-Perch; however, impacts to this sector have not been realized.

There is little or no evidence to support that Ichthyocotylurus pileatus has significant beneficial effects in the Great Lakes.
Potential:
Non-native Great Lakes species found harboring larval or immature I. pileatus include Eurasian Ruffe (Gymnocephalus cernuaus) (Pronin et al. 1998) and Round Goby (Neogobius melanostomus) (Pronin et al. 1997b). Ichthyocotylurus pileatus is unlikely to have significant effects in terms of regulating the Round Goby population in the Great Lakes (Pronin et al. 1997b). It is possible, however,  that its presence in combination with that of other more prevalent parasites in Eurasian Ruffe increases this species’ susceptibility to the negative effects of anoxia (Pronin et al. 1997a).

Regulations (pertaining to the Great Lakes)
There are no known regulations for this species.

Note: Check federal, state/provincial, and local regulations for the most up-to-date information.

Control
Biological
There are no known biological control methods for this species.

Physical
There are no known physical control methods for this species.

Chemical
There are no known chemical control methods for this species.

Note: Check state/provincial and local regulations for the most up-to-date information regarding permits for control methods. Follow all label instructions.