The Truth About Snails In Your Pond

Pond Snails – Basic Facts

1. The more coils, the older the snail
2. Most snails live two-five years
3. Freshwater snails lay their eggs in the Spring
4. Freshwater snails are found in lakes, ponds, marshes, swamps, streams and rivers.
5. There are two types of snails (gilled and lunged) 
6. Freshwater snails that have gills can’t survive in low oxygen levels
7. High numbers of lunged snails may indicate that water is of poor quality
8. Freshwater snails are eaten by fish, waterfowl, and some amphibians!

What Kinds of Snails are Located in the WNY Area?

The Banded physa (Physella vinosa) is the most common freshwater gill-breathing mollusk in New York. This snail is found most commonly in freshwater habitats such as ditches, ponds, lakes, small streams, and rivers. 

According to the New York State Department of Environmental Conservation (NYSDEC), https://www.dec.ny.gov/docs/wildlife_pdf/spcnfreshmollusk.pdf the banded physa is found in Ontario, Canada and the United States, Great Lake states (Minnesota, Montana, Wisconsin, New York, and Michigan), and is most abundant on hard surfaces and aquatic vegetation (Mackie et al. 1980).

These snails have restrictions for where they can call home due to their need for calcium concentrations to be greater than 3mg. 

The Buffalo pebblesnail (Gillia altilis)

This is most commonly found along the Atlantic coastal drainage. It is seen most in New York, Vermont, and South Carolina. These snails were found more in springs, creeks, and small rivers.

Today, they are seen more in stagnant and lake-like environments. Compared to the Banded physa, the Buffalo pebblesnail is much larger. A neat feature the pebblesnail has is the opening to the fleshy part that closes off to predators and protects itself. This snail can be identified by noticing the faint stripes running horizontally down the shell. 

The Campeloma spire snail / midland snail (Cincinnatia cincinnatiensis)

This snail is found in greater quantities around the Erie Canal, and in permanent lakes and ponds in NY. Their habitats include muddy and sandy areas that lack vegetation. The spire snail needs water with a much higher pH between 7.9-8.4, and is in need of high calcium to thrive well. Similar to the Buffalo pebblesnail, this species also has the handy “trap-door” feature to protect it’s flesh.

The Cepaea nemoralis

Known more commonly as the brown-lipped / English garden snail. This snail resembles a bee-like striped and colored pattern.

These snails are pretty to look at, and enjoy moist and mossy rocks around your pond. These snails are land snails, so they won’t be eating what is on the bottom of your pond, but they are very aesthetically pleasing to the similar environment.

How Should I Introduce Snails to My Pond?

The process for introducing snails to your pond is very similar to that of fish. Firstly you definitely want to make sure the plastic bag the snails are not in direct sunlight when placing it into the water.

The last thing you want to do is cook your new addition to the pond! Let the snails sit in the bag for about ten minutes to allow them to adjust to the temperature of the water.

After letting it sit for ten minutes, add half pond water to the bag and close it; have the snails sit for an additional ten minutes. Now you are ready to introduce them to the pond directly. Do not dump the bag water into your pond because it may cause problems with the other life in your pond. 

Understanding How A Snail Eats

        radula

1. Snails are members of the class Gastropoda, this term is derived from the Greek language meaning “stomach and foot”, this comes from the mistaken idea that their foot is also their stomach. In fact their guts are actually located in that part of the snail that stays inside its shell, not the outer part.
2. Snails use what is called a radula to aid them in digestion. A radula is the snail’s specialized version of a tongue. Snails do not have a mouth like you and me, so this ribbon-like organ allows them to feed on algae.
3. The radula has many “teeth” on its membrane, called “denticles”. These denticles are constantly being shed off and regrow just like the cells on our tongues. The denticles shred the food before it enters the esophagus; similar to how we chew our food before it enters our esophagus. See the picture below.

Why Should I Use Snails in My Pond? 

Snails can help you indicate how your ecosystem is doing because of their sensitivity to water quality. Jeff Klinger, owner of www.backyardwatergarden.com recommends the use of the Buffalo pebblesnail in ponds. “They are hearty and healthy little guys that love to snack on my algae. How they survive in my pond with all my fish is so impressive.” says Jeff.

This spring he had a difficult time keeping his string algae in check, that is until he received some help from the snails he introduced. The snails feed on the slime the string algae lives off of.

Without that slime you will see a great reduction in the string-like nuisance. Whether you have an algae problem, or you are looking for a new addition to add more life to your pond, these snails won’t disappoint.

About the Author: Katelyn Elizabeth

I grew up in Newfane, a small farm town in Western New York. Ever since I was a little girl, I always had a great interest and love of nature and the outdoors. After several internships at the Buffalo Zoo, and various other farm-like settings.

I was able to complete my Life Science degree in Animal Management. This accomplishment is an honor, being that it is only offered in 8 other schools in the country. A big thank you to my parents for encouraging me to do what I love, and to continue my journey through my writing. 

Works Cited:

NYSDEC https://www.dec.ny.gov/docs/wildlife_pdf/spcnfreshmollusk.pdf