The distribution of the invasive New Zealand mud snail (Potamopyrgus antipodarum) in streams in the Lake Ontario and Lake Erie watersheds

Edward Levri,Rachel Bilka,Brittany Smith,Elissa Colledge

doi:10.3391/bir.2012.1.3.07

Abstract

The invasive New Zealand mudsnail, Potamopyrgus antipodarum, is a small freshwater hydrobiid snail with populations in western US rivers and streams and in the Laurentian Great Lakes. The snail has had established populations in the Great Lakes since at least 1991 and in one stream emptying into Lake Ontario since at least 2007. This study’s purpose was to broadly survey streams and rivers emptying into Lakes Ontario and Erie to determine the extent of the species’ lotic invasion in the Eastern US. In the summer of 2011, over 100 sites were sampled from the Niagara River, NY to Oswego, NY along Lake Ontario and over 80 sites from Buffalo, NY to the Pennsylvania-Ohio State line along Lake Erie. At each site, general observations of the stream were made and the organisms living in the stream were surveyed for the presence of New Zealand mud snails. Potamopyrgus was found at the site of original discovery and at one additional location along Lake Ontario. In addition an unusual snail was discovered that was a hybrid between a native species (Pleurocera livescens) and an invasive (Pleurocera virginica). This hybrid was extremely abundant in several locations and may be invasive.

Highlights

While it is unclear what the ecological consequences are of the presence of the snail in the Laurentian Great Lakes (Levri et al 2008), the spread of this species into streams and rivers could result in substantial ecological problems including altering the nitrogen and carbon cycles (Hall et al 2003), outcompeting native grazers (Kerans et al 2005; Riley et al 2008), dominating secondary production (Hall et al 2006), and negatively influencing higher trophic levels (Vinson and Baker 2008; Bruce and Moffitt 2010)
After sending a sample of the unknown snails to Dr Robert Dillon of the College of Charleston, the unknown snail was determined by morphological analysis to be a hybrid between the native Pleurocera livescens (Menke, 1830) and the invasive Pleurocera virginica (Say, 1817) (Bianchi et al 1994)
Neither P. antipodarum nor the hybrid was found in Lake Erie streams (Figure 3)

Summary

Introduction

The New Zealand mudsnail, Potampyrgus antipodarum (J.E. Gray, 1843) (Figure 1), is a small freshwater hydrobiid snail with introduced populations in western US and far western Canadian rivers and streams and in the Laurentian Great Lakes (Proctor et al 2007; Davidson et al 2008). In 2007, one population of the snail was discovered in a small stream in upstate NY near Lake Ontario (Levri and Jacoby 2008) While it is unclear what the ecological consequences are of the presence of the snail in the Laurentian Great Lakes (Levri et al 2008), the spread of this species into streams and rivers could result in substantial ecological problems including altering the nitrogen and carbon cycles (Hall et al 2003), outcompeting native grazers (Kerans et al 2005; Riley et al 2008), dominating secondary production (Hall et al 2006), and negatively influencing higher trophic levels (Vinson and Baker 2008; Bruce and Moffitt 2010). In this study we report on surveys of streams emptying into Lakes Ontario and Erie from 2008 and 2011 to determine if the snail has expanded its invaded range since its discovery in a New York stream in 2007

Methods

Results

Conclusion