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126 snail and slug facts, all checked

Every fact on this site, in one place, each linked to its source. Figures that can change carry the date we checked them (30 Oct 2026). Where sources disagree we give every figure: see when sources disagree.

Jump to: Snails and slugs in general | Britain | Bodies and senses | Slime, and the slugs | Life cycle | Food | Finding and recording them | The snails | The Isle of Man

Snails and slugs in general

  1. 1 Snails and slugs are gastropods, a kind of mollusc. ‘Gastropod’ means ‘stomach foot’. The Wildlife Trusts: Yellow slug
  2. 2 Gastropods glide along on a large foot, but it isn’t really their stomach: in snails, the stomach is tucked away inside the shell. Australian Museum: Snails and slugs
  3. 3 There are more than 65,000 kinds of gastropod, the largest group of molluscs: about 30,000 live in the sea, 5,000 in fresh water and 30,000 on land. Britannica: Gastropod · checked 30 Oct 2026
  4. 4 Snails and slugs make up about 70% of all mollusc species. Australian Museum: Snails and slugs · checked 30 Oct 2026
  5. 5 A slug is a gastropod whose shell has shrunk to a small plate or a few grains inside its body, or has gone completely. Britannica: Slug
  6. 6 Gastropods are one of the few groups of animals that have done well in all three big habitats: the sea, fresh water and land. Britannica: Gastropod
  7. 7 Molluscs are thought to have evolved over 500 million years ago. Natural History Museum, London: For the love of snails and slugs
  8. 8 After arthropods (such as insects and spiders), molluscs are the second biggest group of animals on the planet. Natural History Museum, London: For the love of snails and slugs
  9. 9 The mollusc family also includes clams, mussels, oysters, chitons, squid, octopuses and cuttlefish. Natural History Museum, London: For the love of snails and slugs
  10. 10 Some forest-litter snails are less than 1 mm across, and about 90% of adult snails are less than an inch (2.5 cm) long. Britannica: Gastropod
  11. 11 An acre of British farmland may hold 250,000 slugs. Britannica: Gastropod

Britain

  1. 12 The Natural History Museum says the UK has 100 species of land snail and 46 species of land slug. Natural History Museum, London: For the love of snails and slugs · checked 30 Oct 2026
  2. 13 The RHS says there are over 44 species of slug and 90 species of snail in the UK. Royal Horticultural Society: Slugs and snails · checked 30 Oct 2026
  3. 14 The Wildlife Trusts say there are around 150 species of slugs and snails in the UK. The Wildlife Trusts, 14 March 2024: The Wildlife Trusts and RHS ask gardeners to make friends with molluscs · checked 30 Oct 2026
  4. 15 A small garden can be home to well over a dozen kinds of slug and snail. Natural History Museum, London: Slime Search (with the Conchological Society)

Bodies and senses

  1. 16 Snails and slugs usually have four tentacles that they can pull in, and the top two carry tiny eyes. Royal Horticultural Society: Slugs and snails
  2. 17 Their eyesight is poor: they can only see differences in light and blurry outlines. Natural History Museum, London: For the love of snails and slugs
  3. 18 They find food by smelling and tasting chemicals, and can follow trails to it. Touch is one of the main ways they sense the world. Natural History Museum, London: For the love of snails and slugs
  4. 19 Snails have light-sensitive cells all over their bodies, so they pull back into their shells if a shadow falls on them. Natural History Museum, London: For the love of snails and slugs
  5. 20 Snails and slugs can’t hear like we do, but they may sense vibrations with their bodies. Natural History Museum, London: For the love of snails and slugs
  6. 21 Snails and slugs eat with a radula, a tongue-like ribbon covered in tiny teeth that works like sandpaper. Natural History Museum, London: For the love of snails and slugs
  7. 22 A slug has 2,000 to 8,000 tiny teeth on its radula, which it uses like a built-in cheese grater. Royal Horticultural Society: 10 fun facts about slugs (7 March 2024)
  8. 23 Slug blood is pale blue or grey. Slugs use copper, not iron, to carry oxygen. Royal Horticultural Society: 10 fun facts about slugs (7 March 2024)
  9. 24 A slug’s breathing hole and most of its organs are on the right side of its body, because slugs evolved from coiled snails. Royal Horticultural Society: 10 fun facts about slugs (7 March 2024)
  10. 25 Most slugs breathe, and poo, through the same hole on the right side of the mantle, the saddle near the head. Royal Horticultural Society: 10 fun facts about slugs (7 March 2024)
  11. 26 A slug still has a shell, but it’s inside, under the thick ‘mantle’ on its back. Natural History Museum, London: For the love of snails and slugs
  12. 27 Slugs have lost their shells many times during evolution, so some slugs are more closely related to snails than to other slugs. Natural History Museum, London: For the love of snails and slugs
  13. 28 Shells cost a lot to make: they need plenty of calcium and energy, they are heavy, and they get in the way underground. Natural History Museum, London: For the love of snails and slugs
  14. 29 Many sea and freshwater snails close their shell with a hard ‘door’ called an operculum. Land snails and slugs don’t have one. Britannica: Gastropod
  15. 30 Land snails and slugs breathe air with a ‘lung’, a cavity that also stores water. Britannica: Gastropod
  16. 31 A snail moves on its foot, a muscle that ripples in waves to push it forward over a trail of slime. Britannica: How fast are snails?
  17. 32 Most snails in the group that includes many land, sea and freshwater snails move at less than 8 cm a minute. Britannica: How fast are snails?
  18. 33 The fastest slug is the tramp slug, recorded at 17.6 metres an hour (29.4 cm a minute). Royal Horticultural Society: 10 fun facts about slugs (7 March 2024) · checked 30 Oct 2026

Slime, and the slugs

  1. 34 Slime works as a glue and stops snails and slugs drying out. It also fights germs. Natural History Museum, London: For the love of snails and slugs
  2. 35 Snail slime is sticky and slippery at the same time. Natural History Museum, London: For the love of snails and slugs
  3. 36 Slime acts like a liquid when pushed slowly and like a solid when pushed fast. Natural History Museum, London: For the love of snails and slugs
  4. 37 Some species make bubbly, foamy slime to put off birds and small mammals. Natural History Museum, London: For the love of snails and slugs
  5. 38 Snails and slugs are covered in mucus to stop them drying out. Royal Horticultural Society: Slugs and snails
  6. 39 Some slugs clean algae off greenhouse glass, leaving patterns behind. Royal Horticultural Society: Who’s who in slugs
  7. 40 The leopard slug is named after the dark spots on its light brown body. Australian Museum: Leopard slug
  8. 41 Leopard slugs are highly territorial and scare off other slugs: a ‘guard slug’! Royal Horticultural Society: Who’s who in slugs
  9. 42 Leopard slugs eat fungi, lichens and dead plants, and are also reported to eat other live slugs. Royal Horticultural Society: 10 fun facts about slugs (7 March 2024)
  10. 43 Leopard slugs pair up hanging from a branch on a rope of slime, then climb back up, eating the rope as they go. Australian Museum: Leopard slug
  11. 44 The Australian Museum gives leopard slugs a size of up to 20 cm. Australian Museum: Leopard slug · checked 30 Oct 2026
  12. 45 The large black slug can be any colour from yellow to black. When disturbed, it shrinks into a hump and rocks from side to side. Royal Horticultural Society: Who’s who in slugs
  13. 46 The yellow slug has a yellow-and-grey mottled body and blue tentacles. It grows up to 10 cm long. The Wildlife Trusts: Yellow slug
  14. 47 The yellow slug lives close to people, in gardens and in damp, dark corners of houses. It eats fungi, rotting matter and vegetables. The Wildlife Trusts: Yellow slug
  15. 48 The ash-black slug is the UK’s biggest slug: it has been known to reach 30 cm long. Royal Horticultural Society: 10 fun facts about slugs (7 March 2024) · checked 30 Oct 2026
  16. 49 The ash-black slug lives in woods and can be a sign of ancient woodland. Royal Horticultural Society: Who’s who in slugs
  17. 50 The grey field slug is small, usually pale buff with dark flecks and a dark net pattern. Royal Horticultural Society: Who’s who in slugs
  18. 51 The green cellar slug is a plump, medium to large slug mottled with greenish blotches. Royal Horticultural Society: Who’s who in slugs
  19. 52 Cellar slugs graze on algae, fungi and rotting bits, and don’t harm gardens. Royal Horticultural Society: 10 fun facts about slugs (7 March 2024)
  20. 53 The shelled slug Testacella has a small flat shell near its tail, lives almost entirely underground and eats worms. Royal Horticultural Society: Who’s who in slugs
  21. 54 Natural History Museum scientists found a rare shelled slug under a concrete slab in the museum’s own gardens. Natural History Museum, London: For the love of snails and slugs
  22. 55 The ghost slug is pure white, almost blind, lives underground and eats earthworms ‘like spaghetti’. Natural History Museum, London: For the love of snails and slugs
  23. 56 It was found in Wales in 2008, and its name ysbryda is Welsh for ‘ghost’: the first scientific name based on the Welsh language. Royal Horticultural Society: 10 fun facts about slugs (7 March 2024)
  24. 57 The ghost slug was new to science when it was found, but it originally comes from Crimea. Natural History Museum, London: Slime Search (with the Conchological Society)
  25. 58 The lemon slug lives only in long-established woodland and eats fungi. Adults come to the surface when the fungi are fruiting. Royal Horticultural Society: 10 fun facts about slugs (7 March 2024)
  26. 59 The tree slug feeds on algae and lichen high up in trees: it climbs up in the evening and comes down in the morning looking shrivelled. Royal Horticultural Society: Who’s who in slugs
  27. 60 The worm slug is very slender and lives underground. It was first found in Britain in 1972 and is now widespread. Natural History Museum, London: Slime Search (with the Conchological Society)
  28. 61 The Budapest keeled slug is 5 to 7 cm long, grey to brown, with an orange ridge along its back. It is common in gardens. Natural History Museum, London: Slime Search (with the Conchological Society)
  29. 62 When it rests, the Budapest keeled slug curls into a C shape. Conchological Society of Great Britain and Ireland: Tandonia budapestensis
  30. 63 Keeled slugs stay mostly underground and sometimes tunnel into potatoes. Royal Horticultural Society: Slugs and snails
  31. 64 The tramp slug has a paler ring round its breathing hole and tiny black flecks on a brownish body. Royal Horticultural Society: Who’s who in slugs

Life cycle

  1. 65 Some glass snails (Vitrina) crawl about on snowbanks in Alpine meadows. Britannica: Gastropod
  2. 66 All slugs and most snails are hermaphrodites: each one is both male and female. Royal Horticultural Society: 10 fun facts about slugs (7 March 2024)
  3. 67 Even so, brown-lipped snails need to pair up before they can lay eggs, which they then bury in soil. The Wildlife Trusts: Brown-lipped snail
  4. 68 A garden snail digs a nest about 2.5 to 4 cm deep with its foot and lays its eggs inside. Dekle & Fasulo, Brown garden snail, University of Florida IFAS Featured Creatures (EENY240)
  5. 69 A garden snail lays 30 to 120 round white eggs at a time, each about 3 mm across. Dekle & Fasulo, Brown garden snail, University of Florida IFAS Featured Creatures (EENY240)
  6. 70 In summer, garden snail eggs hatch in about two weeks. The babies already have shells, but they are thin and see-through. Dekle & Fasulo, Brown garden snail, University of Florida IFAS Featured Creatures (EENY240)
  7. 71 Garden snails grow to 16 to 20 mm across in their first year and 26 to 33 mm by their second. Dekle & Fasulo, Brown garden snail, University of Florida IFAS Featured Creatures (EENY240)
  8. 72 Most snail species only live for one to two years, but in a long wet season they can lay eggs almost all the time. Natural History Museum, London: For the love of snails and slugs
  9. 73 In winter, snails hibernate in a sheltered spot. Many seal their shell with a plug of mucus first, and they are often found clumped together. Natural History Museum, London: For the love of snails and slugs
  10. 74 When it is too dry, snails can go into a sleep-like rest called aestivation. Natural History Museum, London: For the love of snails and slugs
  11. 75 In dry weather a garden snail can stick itself to a surface or close its shell with a papery seal called an epiphragm. Dekle & Fasulo, Brown garden snail, University of Florida IFAS Featured Creatures (EENY240)
  12. 76 Some land snails live above the snow line, and some desert snails stay inactive for years between rains. Britannica: Gastropod
  13. 77 Most slugs can fertilise their own eggs if they have to, though mating is the usual way. Royal Horticultural Society: 10 fun facts about slugs (7 March 2024)

Food

  1. 78 Most snails and slugs eat dead and rotting plants, not living ones, so they are important recyclers. Natural History Museum, London: For the love of snails and slugs
  2. 79 Slugs and snails are nature’s clean-up crew: they eat rotting plants, fungi, dung and even dead animals, putting nutrients back into the soil. The Wildlife Trusts, 14 March 2024: The Wildlife Trusts and RHS ask gardeners to make friends with molluscs
  3. 80 Fewer than a quarter of Britain’s slug species are big plant-munchers. Royal Horticultural Society: 10 fun facts about slugs (7 March 2024)
  4. 81 Snails and slugs are food for birds, frogs, toads, hedgehogs, slow-worms and ground beetles. Royal Horticultural Society: Slugs and snails
  5. 82 Song thrushes break open brown-lipped snails by banging them on a stone ‘anvil’. The Wildlife Trusts: Brown-lipped snail
  6. 83 Slugs feed at night, so holes and slime trails are often the only clues. Royal Horticultural Society: Slugs and snails
  7. 84 Slugs and snails are most active at night, so an evening walk with a torch is a good way to find them. The Wildlife Trusts, 14 March 2024: The Wildlife Trusts and RHS ask gardeners to make friends with molluscs
  8. 85 A few snails eat other snails, drilling through their shells with the radula. Natural History Museum, London: For the love of snails and slugs
  9. 86 The Natural History Museum’s mollusc curator suggests not using slug pellets, as they might build up in other animals. Natural History Museum, London: For the love of snails and slugs
  10. 87 The Wildlife Trusts and the RHS suggest growing plants slugs tend to leave alone, such as lavender, rosemary and hardy geraniums. The Wildlife Trusts, 14 March 2024: The Wildlife Trusts and RHS ask gardeners to make friends with molluscs
  11. 88 Log piles, leaf mulch and long grass give slugs and snails, and the animals that eat them, a place to live. The Wildlife Trusts, 14 March 2024: The Wildlife Trusts and RHS ask gardeners to make friends with molluscs

Finding and recording them

  1. 89 Snails and slugs need to stay wet, so you are most likely to see them when it’s raining. Natural History Museum, London: For the love of snails and slugs
  2. 90 Look under stones, slabs and pieces of wood. In mild weather and at night they often climb bushes, tree trunks and walls. Natural History Museum, London: Slime Search (with the Conchological Society)
  3. 91 Empty shells can be a clue that living snails are nearby. Natural History Museum, London: Slime Search (with the Conchological Society)
  4. 92 Many snails are smaller than people expect, so get down close to the ground to look. Natural History Museum, London: Slime Search (with the Conchological Society)
  5. 93 To help name a slug, scientists like three photos: from above, from the right side and of the underside of the foot. Natural History Museum, London: Slime Search (with the Conchological Society)
  6. 94 Slugs are hard to name: experts look at the breathing hole, the mantle and even the colour of the sole and slime. Royal Horticultural Society: Who’s who in slugs
  7. 95 The Conchological Society of Great Britain and Ireland has run the national recording schemes for molluscs since 1876. Natural History Museum, London: Slime Search (with the Conchological Society)
  8. 96 Some native species are getting rarer because of towns spreading and pollution, while some newcomers are spreading quickly. Natural History Museum, London: Slime Search (with the Conchological Society)

The snails

  1. 97 The common garden snail is found all over the UK. It mostly comes out at night, or when it rains. Natural History Museum, London: For the love of snails and slugs
  2. 98 Its shell is 25 to 35 mm tall, usually pale brown with up to five dark spiral bands, and has a thick white lip. Conchological Society of Great Britain and Ireland: Identifying common British snails, Garden snail
  3. 99 Garden snails are widespread in cities around the world. In Australia, introduced snails like this have two pairs of tentacles, while the native snails and slugs have one pair. Australian Museum: Garden snail
  4. 100 Its scientific name is Cornu aspersum. It used to be called Helix aspersa. Conchological Society of Great Britain and Ireland: Identifying common British snails, Garden snail
  5. 101 The brown-lipped snail has a dark brown band round the opening of its shell, and up to five brown bands on the shell. The Wildlife Trusts: Brown-lipped snail
  6. 102 Its shell can be yellow, pink, brown or red. This variety is thought to help camouflage it. The Wildlife Trusts: Brown-lipped snail
  7. 103 Brown-lipped snails are 2.0 to 2.4 cm across. The Wildlife Trusts: Brown-lipped snail
  8. 104 The white-lipped snail looks like the brown-lipped snail, but is usually smaller and has a white lip round its shell opening. The Wildlife Trusts: White-lipped snail
  9. 105 It likes to eat nettles, ragwort and hogweed. The Wildlife Trusts: White-lipped snail
  10. 106 White-lipped snails are 1.6 to 2.2 cm across. The Wildlife Trusts: White-lipped snail
  11. 107 Banded snails can be yellow, pink or brown, with different numbers of bands or none at all. They eat decaying plants. Natural History Museum, London: For the love of snails and slugs
  12. 108 The Roman snail can grow as big as 5 cm and lives in forests and shrubland. Natural History Museum, London: For the love of snails and slugs
  13. 109 In England, Roman snails are protected by law: it is illegal to kill, injure, collect or sell them. Natural History Museum, London: For the love of snails and slugs
  14. 110 Roman snails were probably brought to Britain in Roman times, 2,000 years ago, and are found on chalk soils in southern England. Natural History Museum, London: Slime Search (with the Conchological Society)
  15. 111 If you spot a Roman snail, don’t move or disturb it. Natural History Museum, London: Slime Search (with the Conchological Society)
  16. 112 The Turkish escargot has a huge, almost round, rich brown striped shell up to 45 mm wide. It arrived from Europe in the last 50 years. Natural History Museum, London: Slime Search (with the Conchological Society) · checked 30 Oct 2026
  17. 113 The Kentish snail is up to 15 mm wide, usually white or see-through, with a red-brown tinge round the opening. It likes road verges and waste ground. Natural History Museum, London: Slime Search (with the Conchological Society)
  18. 114 It comes from the Mediterranean, is common in the south-east, and is spreading north and west. Natural History Museum, London: Slime Search (with the Conchological Society)
  19. 115 The girdled snail is 10 mm wide with a sharp, pale ridge round the edge of its shell. It has spread fast across British towns this century. Natural History Museum, London: Slime Search (with the Conchological Society)
  20. 116 The two-toothed door snail is slender, brown or grey and only 10 mm long. It climbs trees and walls to eat lichens and algae. Natural History Museum, London: Slime Search (with the Conchological Society)
  21. 117 The largest land snail, the African Achatina achatina, has a shell almost 20 cm long. Britannica: Gastropod
  22. 118 Large tropical land snails such as Achatina are very slow movers. Britannica: How fast are snails?

The Isle of Man

  1. 119 About 66 kinds of land snail are known from the Isle of Man, compared with around 134 for the British Isles as a whole. Alexander & Dubbeldam 2013, A survey of ancient woodland indicator molluscs in selected sites on the Isle of Man, Journal of Conchology 41(3) · checked 30 Oct 2026
  2. 120 In August 2011, a week-long survey of wooded glens on the island found 36 kinds of mollusc across eight sites, almost all of them native. Alexander & Dubbeldam 2013, A survey of ancient woodland indicator molluscs in selected sites on the Isle of Man, Journal of Conchology 41(3)
  3. 121 The key find was an ash-black slug at the edge of Brookdale, above Ramsey, on 17 August 2011: apparently the first seen on the island for over 100 years. Alexander & Dubbeldam 2013, A survey of ancient woodland indicator molluscs in selected sites on the Isle of Man, Journal of Conchology 41(3)
  4. 122 The glens surveyed included Ballure Glen, Glen Roy, Groudle Glen, Elfin Glen, Brookdale, Narradale, Silver Burn and Santon Gorge. Alexander & Dubbeldam 2013, A survey of ancient woodland indicator molluscs in selected sites on the Isle of Man, Journal of Conchology 41(3)
  5. 123 Some of the snails and slugs collected were kept for the Manx Museum collections. Alexander & Dubbeldam 2013, A survey of ancient woodland indicator molluscs in selected sites on the Isle of Man, Journal of Conchology 41(3)
  6. 124 Both banded snails, the brown-lipped and white-lipped snail, and the tree slug were among the species found. Alexander & Dubbeldam 2013, A survey of ancient woodland indicator molluscs in selected sites on the Isle of Man, Journal of Conchology 41(3)
  7. 125 In October 2024, the Ellan Vannin Invertebrate Group recorded slugs including the tree slug, green cellar slug and Budapest keeled slug in the grounds of Government House, Onchan. Manx Wildlife Trust: Ellan Vannin Invertebrate Group field report, Government House grounds, Onchan, 19 October 2024
  8. 126 The same survey found the tawny soil slug, which the expert who identified it believed had no earlier records from the island. Manx Wildlife Trust: Ellan Vannin Invertebrate Group field report, Government House grounds, Onchan, 19 October 2024