Infection Patterns in Invasive and Native Snail Hosts Exposed to a Parasite Associated with Waterfowl Mortality in the Upper Mississippi River, USA

Bithynia tentaculata is an aquatic invasive snail first detected in the upper Mississippi River (UMR) in 2002. The snail harbors a number of parasitic trematode species, including Sphaeridiotrema pseudoglobulus, that have been implicated in waterfowl mortality in the region. We assessed the capacity of S. pseudoglobulus cercariae to infect B. tentaculata and native snails found in the UMR. Four snail species (one invasive and three native) were individually exposed to S. pseudoglobulus larvae and all were successfully infected. A subsequent experiment examining infection patterns in invasive and native hosts exposed singly or in mixed treatments revealed no difference in parasite establishment among snail species. Our results add to our understanding of S. pseudoglobulus transmission and provide insight into processes underlying waterfowl disease in the UMR.