Common periwinkle (Littorina littorea) care guide

Group

Snails

Other names

Edible periwinkle, Winkle

Family

Littorinidae

Origin

North-east Atlantic coasts including Britain and Ireland; introduced to North America

Water

saltwater

Maximum size

5 cm

Temperature

4–18°C

Care level

beginner

Lifespan

5–10 years

Care

The common periwinkle is the familiar winkle of British rocky shores: a marine snail with a thick, broadly oval, sharply pointed shell of six or seven whorls, grey to grey-brown with dark spiral bands and a chocolate-brown inside. The shell is typically 1.6–3.8 cm long and can reach about 5 cm. It is native to Britain and the north-east Atlantic from northern Spain to Scandinavia and Russia, and was introduced to the north-west Atlantic, probably in rock ballast, in the mid-19th century. Native species: it is native to Britain, needs a coldwater (unheated) marine tank and should not be collected from the wild where that is not allowed. It lives on the middle and upper shore and in tide pools and estuaries, down to about 55 m, and survives exposure by sealing itself into its shell. It is not suited to a tropical reef tank, where it will not live long. Water figures given here are general hobby guidance rather than taken from our sources. Clean-up role: it grazes algae and biofilm from rock and glass with its radula, and is a good grazer for a coldwater rock-pool aquarium. It also eats small invertebrates such as barnacle larvae. Some brown seaweeds (bladder wrack and knotted wrack) contain chemicals that deter it. Periwinkles are an important food in Britain; over 2,000 tonnes are collected in Scotland each year. Copper: copper-based medicines and some plant fertilisers are toxic to shrimp, snails and most other invertebrates. Never dose them in a tank holding this animal, and check the label of any treatment or fertiliser before use. Sources: Wikipedia (en.wikipedia.org/wiki/Commonperiwinkle). Checked October 2026.

Diet

Omnivorous grazer, mainly of algae and biofilm scraped from rock and plants; also takes small invertebrates. In a coldwater tank supplement with dried seaweed (nori) or algae wafers if natural growth runs short.

Breeding

Separate sexes with internal fertilisation. Females release 10,000–100,000 eggs in floating capsules, and the larvae drift in the plankton for four to seven weeks before settling. Maturity is reached at about 18 months or 1 cm shell size; spawning peaks from February to May. The planktonic larvae are almost never raised in aquaria. Lifespan is usually five to ten years, occasionally up to about 20.

Compatibility and tank mates

Peaceful and harmless to fish and other invertebrates in a coldwater marine tank. Eaten by shore crabs and some fish. Not for tropical reef tanks.

Last updated 8 October 2026. Community-edited care guide on Aquatic-Auctions.