Survival rates of adult and juvenile Japanese Mystery Snails (Heterogen japonica) undergoing desiccation.

Abstract

The invasive Japanese Mystery Snail (Heterogen japonica) has invaded North American freshwater environments after having been introduced in 1892. The subsequent spread has been attributed to recreational activities. Thus, it is imperative to determine the survival rate of the Japanese Mystery snail when exposed to air in order to understand its invasive ecology and likelihood of introduction to new environments. To do this, adult mystery snails (34-54 mm) were incubated on a diurnal cycle. The temperature during the 12 hours with light was maintained at 32.2℃ while the 12 hours without light was maintained at 21.1℃. Conversely, the juvenile snails (4-9 mm) were given constant light with a consistent temperature of 32.2℃. Fifteen adult snails were pulled every Monday, Wednesday, and Friday, then placed in water to check for mortality. Around 30 juvenile snails were pulled each hour for 24 hours. As of two weeks, adult snails have not shown mortality. The juvenile snails, however, began dying after 18 hours in the incubator (59% mortality). Therefore, juvenile snails would be unable to survive boating and fishing net transportation if exposed to air for an elongated amount of time; whereas, adult snails can survive extensive air exposure.