Waipio Valley Stream Restoration Study

Molluscs: Introduced Species

Scientific name: Physa sp.
Common name(s): Pouch snail or Tadpole Snail

Physa sp.

Status: Introduced

Habitat: Slow-moving portion of streams, wetlands and kalo lo‘i

Preferred Area of Stream: Slow areas with shallow water and pouch snails are often attached to rocks at the edge of the stream, or in shallow, slow water

Range in Hawai‘i: Common on all Hawaiian Islands

Diet: Freshwater algae

Predators: Native and introduced fish, ducks

Fact: This introduced snail species is the only aquatic snail in Hawaii with the opening of the shell pointing to left. That is, when you hold the tip of the shell pointing straight ahead of you the opening of the shell will be to the left.