Helix pomatia Linnaeus,1758
Description:Shell spherical with a conical spire,very strong with thin axial lines.The aperture is round and the lip thin. The umbilicus is narrow and covered by the edge of the columella in a way that leaves only a slitlike opening visible.In some cases the umbilicus is completely covered. In old shells the periostracum is often worn away giving the surface a whitish color. There are 4.5-5 whorls,shellsize is 32-50 mm wide and 30-50 mm high. The color is light yellowish brown to whitish grey,often with 3 faint mauve or dark violet bands. Habitat:Copses,thickets,parks,gardens and vineyards.The snail prefers a chalky substrate in warm low lying country. Distribution:Orginally from Central- and Southeast Europe this species has spread out towards other areas mainly by human hands. From South-Denmark southwards to Central-Italy,westwards to France and Southern England, eastwards to Russia(Riga).It has been introduced in the USA as well(Michigan). In some areas(especially France)overcollecting has greatly diminished the numbers of H.pomatia.In some countries in Europe this species has been put on the Red list of endangered animals. Life-history:Helix pomatia is sexually mature after 2-4 years.They mate usually from May-July or August.In the mating process 5 stages can be recognised: In the first stage the snails crawl around eachother,then touch eachother with their tentacles,the front part of the bodies and the mouths.In the second stage the snails crawl against eachother,usually in one of the snails reproductive-opening a white genitalorgan appears. A love-dart is being pushed inside the body of the other snail,sometimes both snails use a love-dart and sometimes no dart appears at all.After this has happened the snails are passive. In the third stage the snails get active again and repeat the touching as was seen in stage one.The reproductive organs of both snails appear,and are pushed against eachother. A number of attempts to mate follow,this is probably to arouse the partner more. After this the organs are retracted into the bodies again. In the fourth stage the actual mating happens.This lasts about 4-7 minutes. Normally only one snail exchanges the spermatophore(package with sperm). Research has suggested that one snail acts as "male",while the other acts as the "female".The "males" seem to be darker in body color than the "females" and the snails acting as the "males" are the youngest of the couple. The fifth and last stage sees the withdrawal of the reproductive organs.The snails seem to be exhausted and lay with their soles against eachother.They can stay in this position for hours. About 4-6 weeks after mating the eggs are being laid in a hole dug in the ground. The eggs are circa 5 mm in diameter and surrounded with slime.After about 25 days the eggs hatch,but this depends on climatic conditions. After hatching the young snails stay under the ground for a week till 10 days. There they will eat the eggshells.In the first season the snails will reach a size of 10 mm but kept in captivity this will be bigger. Helix pomatia can reach an age of 5 years in the wild or twice as much when kept in a tank.
Hibernation and aestivation:Helix pomatia spends a large period of its life either in hibernation(winterrest) or aestivation(during dry spells). Hibernation can start in the middle of autumn(October)when the temperatures drop to 8 degrees Celsius. The snails find a spot in moss,in grass or under leaves,usually they dig a hole in the ground.The mantle secretes a chalky substance which together with slime forms a hard epiphragma.Then the snail releases some air and withdraws further in the shell,a second epiphragma is formed but this one is not chalky. This can be repeated till up to 6 "doors" are built,between these "doors" is air,making this a series of airchambers. Depending on weatherconditions Helix pomatia hibernates till March or April.Raising temperatures and humidity are crucial factors. Nightfrosts in the Spring can cause many fatalities among the snails which have little resistance when they first come out of hibernation. Aestivation happens when humidity drops and increasing dryness causes the snails to be slower.They will seal of the shell with one or more layers of slime.During aestivation they will loose a lot of water,about 2.5 times more than in hibernation.
Enemies:Adult Helix pomatia have relative few natural enemies because of their size and stronge shells,but young snails are ofcourse always vulnerable. Keeping them as pets:Because of their endangered status in a lot of countries Helix pomatia should not be collected from nature. Sometimes you can find babies for sale. Look at the native snails/slugs general care sheet for info on keeping them as pets.