New Zealand mud snail
(Potamopyrgus antipodarum (J.E. Gray, 1853))

Overview

Description

New Zealand mud snail has a light tan to brownish, tiny, elongate, right-coiling shell of less than 0.25 in. (0.64 cm) length in Great Lakes populations (although it has been observed to nearly 0.5 in. [1.3 cm] in its home range).

Habitat and Habits

New Zealand mud snail is native to the fresh waters of New Zealand and nearby small islands. It occupies any shallow water (estimated less than 150 ft. [45.7 m]).

Ecological Threat

New Zealand mud snail can form dense populations and may crowd out native grazers and snails and prevent colonization by other macroinvertebrates, like native insects, including sensitive species that are indicators of ecosystem health. It is very tolerant of poor water quality, a wide range of temperatures, transport on mats of algae, and can even pass through the guts of fish alive. Densities greater than 300,000 individuals per square meter have been observed in Montana, making New Zealand mud snail a likely candidate as a biofouling nuisance at water intakes. It can also carry parasites that infect native snails and fish. Be careful to decontaminate fishing and sporting equipment so as not to spread existing populations or start new ones.

Resources

• Global Invasive Species Database - Invasive Species Specialist Group
• Nonindigenous Aquatic Species Database - U.S. Geological Survey

Selected Images

Maps

Invasive Listing Sources

• Alberta Fisheries Act
• Idaho Invasive Species Act
• Maryland Aquatic Nuisance Species Plan
• Maryland Invasive Species Council - Invasive Species of Concern in Maryland
• Michigan’s Invasive Species Watch List
• Michigan’s Prohibited and Restricted Species
• Mid-Atlantic Field Guide to Aquatic Invasive Species
• Minnesota DNR invasive species list
• New Jersey Invasive Species Strike Team 2017 Invasive Species List
• New York Regulated and Prohibited Invasive Species - Prohibited
• Ontario’s Invading Species Awareness Program Tracked Species List
• Pennsylvania's Field Guide to Aquatic Invasive Species
• Virginia Invasive Species Management Plan 2012
• Wisconsin's Invasive species rule – NR 40

References