What do they look like?

The thin shell has a reddish apex and is a translucent, glossy tannish to brownish-olive color. The shell is sinistral (coiled to the left) with a long opening and can become as much as one inch high and two-fifths of an inch wide. Five and one-half to six whorls are present.

The body is darkish gray with tiny white or yellow dots. The foot is narrow with a rounded front and a tapered point at the back and the mantle lobes protrude over the foot.

Like other snails, pond snails use a pneumostome, or breathing pore, for respiration.

Where in the world do they live?

Pond snails are very commmon in North America, and especially in Michigan.

What kind of habitat do they need?

This snail is found in both permanent and temporary pools, swamps, and other flooded areas. They are found on rocks in wetland areas.

How do they reproduce?

Pond snails are capable of cross-fertilization as well as self-fertilization. Egg masses are jelly-like and transparent containing whitish, cresent-shaped eggs. As many as 200 eggs may be laid. At hatching, a pond snail has a shell length of approximately 1/33 of an inch. After 6 weeks, the shell length increases to approximately 2/5 of an inch in length. After 10 weeks, little growth occurs, and the shell may be approximately 1/2 inch in length.

How long do they live?

Pond snails can live to be at least a year old.

How do they behave?

This snail can move at approximately 2.4 inches per minute. It is able to right itself and in running water will head upstream. Pond snails will crawl upside down on the under side of the water surface, but also drop to the bottom to avoid predators. To breathe, a pond snail must return to the surface to gain access to the air.

What do they eat?

Pond snails have a radula, or hard tooth-like structure, with V-shaped rows of teeth. They use it to feed on algae and diatoms.

What eats them and how do they avoid being eaten?

When touched by a predator, a pond snail will thrash its shell from side to side. Also, if disturbed, the snail will expel air and retract into its shell, then fall to the bottom of a pond and remain there for as long as one hour until it must return to the surface to breathe. Finally, if it does get bitten by a predator, a pond snail is capable of growing a new tail section.

What roles do they have in the ecosystem?

Like other snails, pond snails may be an intermediate host for parasites.

How do they interact with us?

Pond snails are tolerant of polluted and brackish waters and may serve as an indicator species of water conditions.

Some more information...

Physa snails may be difficult to distinguish from other kinds of pond snails in the same family, such as Physella. Physa and Physella both are very variable in appearance and are found in similar habitats.