- Slimy fellows
- Different ages
- Nudibranchs and shell snails
- Life expectancy of individual snail species
- Natural predators
- frequently asked Questions
Snails are very old. The ancestors of today's well-known snail species already lived in the seas more than 500 million years ago, in the Palaeozoic. The lifespan of individual species varies greatly.
In a nutshell
- need moisture to live
- Age dependent on size, habitat and manner
- Shell snails have a longer life expectancy than slugs
Slimy fellows
Snails (Gastropoda) belong to the mollusks (Mollusca). They populate the most diverse habitats on earth. Some live in salty seas, other species live in freshwater, and others live on land. They are mostly nocturnal. All snail species need moisture to live. In general, the mollusks are divided into slugs and shell snails. There are various differences here, including the expected lifespan. However, other factors also determine how old a snail becomes.
Spanish slug (Arion vulgaris)
Notice: Nudibranchs in particular, and especially the Spanish slug, are a horror for everyone hobby gardener. In one night they can eat a whole vegetable patch bare.
Different ages
The life expectancy of the individual snail species is quite different. Various factors determine how old a snail becomes. This includes
- habitat
- way of life
- size of the snail
- predators
As a rule, an indication of between nine and twelve months is given, whereby representatives of smaller snail species do not get as old as larger ones. Life expectancy can also vary within a species. This depends, among other things, on the weather and local conditions.
Red slug (Arion rufus)
Notice: A snail covers a distance of one millimeter in one second.
Nudibranchs and shell snails
Compared to slugs, snails have a longer life expectancy and can reach a very considerable age. Due to their existing snail shell, they can survive some difficult living conditions well. This offers protection against
- dehydration
- cold winters
- Snail withdraws
- seals the house with a lime lid
- lasts for several months
Snail eggs in the ground with small snail
Nudibranchs have it a little harder. Most adult snails rarely survive very cold winters. In mild weather, however, survival in frost-free soil is possible. Often only the eggs laid in the ground overwinter. The young hatch in the spring and become sexually mature in the summer. Shortly thereafter, they lay eggs. Most slugs rarely get older than one to two years.
Life expectancy of individual snail species
According to NABU, the probably oldest snail is a Roman snail (Helix pomatia) that lived in a terrarium. She was 30 years old. In the wild, representatives of this species also reach a quite stately age of six to ten years. There are also species that also have a good life expectancy and others that are very short-lived:
| snail species | Maximum life expectancy |
|---|---|
| Grass slug (Deroceras reticulatum) | 1 year |
| Apple snail (Ampullariidae) | 3 to 4 years |
| Garden snail (Cepaea hortensis) | up to 5 years |
| Large agate snail (Achatina fulica) | ten years |
| Grove snail (Cepaea nemoralis) | 8 years |
| Ramshorn snail (Planorbarius corneus) | 3 years |
| Red slug (Arion rufus) | up to 3 years |
| Black Slug (Limax cinereoniger) | 2 years |
| Spanish slug (Arion vulgaris) | 1 to 2 years in mild areas |
| Tiger Slug (Limax maximus) | 3 years |
| dwarf snails | 1 year |
Garden snail (Cepaea hortensis)
Natural predators
Many snails sometimes do not reach their normal life expectancy. They are a real delicacy for their natural predators such as hedgehogs, mice, martens and birds. In addition, very cold winters or prolonged drought can kill the molluscs. In addition, some types of snails are not welcome in the garden, especially the voracious slugs. They are specifically targeted there.
Hedgehog
Notice: Various types of snails such as the agate snail or Roman snail can be kept in terrariums at room temperature. Here they have a longer life expectancy than normal.
frequently asked Questions
Are poisonous species known among the snails?There are also poisonous snails, but these are mainly only found in tropical seas. These include the cone snail (Conidae). It produces the strongest known natural toxin. In this country, no poisonous animals can be found among the terrestrial and freshwater snails. However, after contact with them, hands should still be washed thoroughly.
How can the different snail species survive the winter?Snails are hardly visible from autumn to spring. They are looking for a place to overwinter early. Since slugs don't have a house, they hide in the frost-free ground. The situation is different with the so-called shell snails. They look for a sheltered place, for example under dense bushes in the moss. On the other hand, the field slug, two millimeters in size, is also active in frosty temperatures in damp leaves or under the snow cover.
How do these mollusks reproduce?As a rule, almost all terrestrial and freshwater snails lay eggs. The young then hatch from them. Depending on the type of snail, the eggs are white or transparent and have a diameter of three to four millimeters. After mating, up to 400 eggs are laid in clutches of 30 to 70 pieces. Since the molluscs are hermaphroditic, both animals lay their eggs. Depending on the weather, storage can take place up to twice a year, in spring and autumn.
Do snails already have houses when they are born?Yes. Animals that have already hatched have a small embryonic shell. In adult animals, this is often still recognizable as a point. The housing grows with the young animal. If the snail then stops growing, the house will not continue to grow either.