The common species here in South Jersey in the lesser pond snail, galba truncatula. They are small invertebrates, usually measuring between 2-8mm long. They are silent little creatures that eat the slime algae along the rocks in your pond. These snails are often introduced to a pond by hitching along on some aquatic plants; juvenile snails and eggs are very small and can easily avoid detection. In the plant pools at any outdoor nursery, you are likely to see many snails, they enjoy a safe life away from predators in those little pools.
SNAILS EAT ALGAE, SO THEY’RE GOOD, RIGHT? IT’S NOT THAT SIMPLE. UNDERSTANDING A SNAIL’S PLACE IN YOUR POND’S ECOSYSTEM REQUIRES KNOWING ABOUT THREE DIFFERENT TYPES OF ALGAE: SLIME ALGAE, STRING ALGAE, AND PLANKTONIC (PEA SOUP) ALGAE SLIMY ALGAE IS THE STUFF THAT GROWS ALONG ROCKS IN YOUR POND. THIS ALGAE IS BENEFICIAL TO YOUR POND AND HELPS FILTER THE WATER AND PROVIDE FOOD FOR FISH. IT HELPS REMOVE EXCESS NUTRIENTS WITHOUT CONTRIBUTING TO CLOUDY WATER. STRING ALGAE IS THE LONG STRANDS OF ALGAE THAT GROW OFF THE ROCKS AND PLANT ROOTS AND IS OFTEN SEEN SWAYING IN A STREAM. THIS IS A PRIME FOOD SOURCE FOR KOI AND GOLDFISH. IN A HEALTHY, BALANCED POND THE FISH WILL KEEP MOST STRING ALGAE BLOOMS UNDER CONTROL, EXCEPT FOR PLACES THE FISH CAN’T REACH SUCH AS ALONG THE STREAM AND ATOP THE WATERFALL SPILLWAY. PEA SOUP PLANKTONIC ALGAE IS THE TYPE MOST DETESTED AMONG POND OWNERS; IT CAN COMPLETELY CLOUD THE WATER AND DETRACT FROM SEEING AND ENJOYING YOUR FISH.
Snails eat primarily slimy algae. They do not eat planktonic algae, and have very little access to string algae except which is touching the rocks or edges of the pond. The friendly slime algae that snails do eat is the same stuff competing with the less-desirable string and pea-soup algae for nutrients, so an overload of snails can lead less-than-optimal levels of slimy algae and higher-than-optimal levels of string or planktonic algae. The proportion of snails to achieve such an imbalance is quite high, and is not likely to occur in a pond populated with fish. Other wild predators also eat the snails, so you may get to enjoy seeing a small bird or mammal snacking on them as a result of their presence in your pond. Just be sure your fish have a secure fish cave or sufficient pond depth (at least 2‘) for them to hide out beyond the reach of curious critters.
- THE ONLY DIFFERENCE BETWEEN A SNAIL AND A SLUG IS THE PRESENCE OF A SHELL
- SNAILS ARE FOUND EVERYWHERE, FROM THE OCEAN FLOOR TO THE MOUNTAINS TO THE FORESTS TO THE DESERT.
- SOME SNAILS HAVE LUNGS, SOME HAVE GILLS, SOME HAVE BOTH.
- SNAILS LIVE BETWEEN 5-25 YEARS
- THE TOP SPEED OF A SNAIL IS JUST .03MPH. IT WOULD TAKE A SNAIL ABOUT 36 HOURS TO TRAVEL ONE MILE!