There is not a slower time in the garden than January when the ground is frozen, often under a blanket of snow, plants have died off or lay dormant, and most insects and small animals are snug underground.

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Among the animals that may hibernate from October to April are slugs and snails, happy to find a site that doesn’t go below 0°F. Their eggs are also capable of withstanding freezing temperatures. So even though we can’t see them right now, they are out there, just waiting for the ground to warm up in the Spring when they can return to our gardens and feed on our new plants!

Slow moving slugs and snails are primordial gastropod mollusks (or molluscs) in the class Gastropoda and are invertebrates that may be found in salt or fresh water or on land. Gastropod is derived from the ancient Greek words ‘gastér’ for stomach and ‘podos’ for foot, their literal means of locomotion. Some land and freshwater snails and slugs have a simple lung from which they breathe while other freshwater snails such as this zebra nerite (Neritina zebra) breathe through gills. This video shows not only how quickly a marine snail can move around on its single foot but also its mouth as it feeds on the algae in this water garden tank.

This grove snail, Cepaea nemoralis, is a pulmonate land snail, meaning that it breathes through a simple lung which is somewhat visible through its translucent shell. A snail is born with a very soft shell and they need to consume large amounts of calcium early on in order for it to harden, starting by consuming the shell of the egg that it hatched from. This tiny newborn shell becomes the center of the coiled spiral that forms as the snail grows.

cepaea_nemoralis

Some shells form into elongated spiral shapes such as the tree snail of the Drymaeus species below on the left and the garden snail, Cornu aspersum on the right.

And then there is the ultimate example of recycling where hermit crabs will occupy marine snail shells whose occupants have died. This fellow was filmed in the Bahamas:

The shell-less gastropods, or slugs, that are common to Connecticut gardens include the netted or grey garden slug, Deroceras reticulatum. It is a major pest which loves to feed on leaves, seedlings, and young fruit such as the developing cucumber shown below. The cucumber is shiny with the slug’s slime.

These small slugs actually thrive in cultivated areas such as our gardens and landscapes, feeding at night and sheltering under stones or litter during the day. An interesting aspect of ‘slug watching’ is seeing their bodies lengthen and thin out and then contract and grow bulbous again as they move along. They almost seem to be formed a of a thickly viscous fluid as they drape over a plant or rock.

Also familiar to the Connecticut gardener is the slug Limax maximus, shown below, so called as it can grow to 5” in length. It is a nocturnal slug that returns to a particular crevice under stones or fallen trees after foraging in lawns, gardens, cellars, or damp areas. Also known as the great grey slug or the leopard slug due to the dark blotches that stand out against the lighter background of its upper body, it is a detrivore, meaning that it feeds on detritus such as dead plants and fungi although it can be a major pest in a garden where it can consume young plants. It will pursue and consume other slugs if it feels threatened.

The black slug, Arion ater, is rarely a pest in gardens, preferring terrestrial areas. This slug will contract into a spherical shape when threatened but can reach up to 4.5” when expanded to its full length.

large black slug, arion ater

Slugs and snails both produce a layer of protective mucus that is a combination of lubricant and glue from their foot which is useful in both movement and in securing the creature to surfaces. Another type of mucus coats the body to prevent desiccation, aid in healing, and protect soft body parts. Snail slime is currently an ingredient in many cosmetics where those same properties are desired, so land snails are bred on farms for the cosmetic industry. Snail farming is known as heliculture or heliciculture which derives its name from the family Helicidae to which snails belong. These farms also grow snails for consumption such as in the traditional French dish escargot or the eggs are eaten in a fashion similar to caviar.

snail damage

If slugs and snails are pests in your garden, eating and damaging plants, then check out our fact sheet Slugs and Snails for information on control options.

 

Susan Pelton

All images by Susan Pelton