Periwinkle snails are nowhere near as blue as the name would lead you to believe, but that doesn’t mean they aren’t incredible little gastropods in their own right. With more than eighty reported species or subspecies, many of which are edible, there’s a chance you’ll have seen this snail without even realizing it.
Why don’t we find out more?
What are Periwinkle Snails?
Also known as winkle, common periwinkle, edible periwinkle, whelk, or the scientific name Littorina littorea, these snails are sea-dwelling creatures. There are a few species and subspecies in the Littorinidae family. Some experts believe there are more than 80 in total. The common periwinkle is, as the name suggests, the most common.
How Big are Periwinkle Snails?
The common periwinkle (Littorina littorea) is the largest of all periwinkles, but the sea snails are still quite small. Larger species can grow to between 1 and 2 inches (3 to 5 cm), but above 1.5 inches (4 cm) is considered quite rare.
With the body and the shell, combined, these snails can actually grow to a greater height than width. From the very bottom of the foot to the very tip of the spiral-shaped snail, it can reach heights of 2 inches (5.2 cm), over four to six whorls or spirals.
What Does the Periwinkle Snail Look Like?
You’d never know this gastropod was a sea snail to look at. Most people actually confuse it with common garden snails and other similar land snail species. That gives you some idea of what it looks like.
The shell of this snail is very round, like a common garden snail. There’s usually between five and seven swirls or whorls, with a pointed tip at the top. Sometimes these tips can be bashed or sanded off by rock, sand, pebbles, other shells, and other things that get washed up on the shore.
The shells are usually darker than their garden snail cousins, very dark brown and grey, almost black in areas. The color tends to go from darker at the bottom of the shell to lighter at the tip.
Where are Periwinkle Snails Found?
These sea snails are found all over the world, but the word ‘sea snail’ sometimes seems a little misleading. Periwinkles spend their time along rocky beaches, and open coasts and shores, up to a depth of 60m. This is especially the case along northern Europe – all the way from the UK to northern parts of Russia.
They avoid open spaces where they can easily become prey to predators flying up in the air, but they can cluster in ‘good’ areas. This includes around large rocks and boulders, in and around rock pools, and shingle or gravel beaches.
You’ll also find these gastropods in North America, after being introduced there in the later part of the 1850s. They tend to favor mud flats, boggy grass areas, and tidal estuaries, and have now become one of the most common types of snails found on coasts of the North Atlantic.
Can Periwinkle Snails Live in Freshwater?
No, periwinkle snails cannot live in freshwater.
This snail species is a sea snail, which means it lives in salt water, or ‘mildly salty’ water. Either way, it is a saltwater species.
What do Periwinkle Snails Eat?
This gastropod lurks along tidal shores to feed, scraping algae and biofilms from rocks and other items in the water, using an appendage known as a radula. This gives it the classification ‘grazing intertidal gastropod’. It literally grazes along the shores when the tides come in and out.
Are Periwinkle Snails Edible?
Yes, periwinkle snails – also known as whelks – are edible. In fact, during Christmastime, demand for this edible snail from markets in France increases massively!
Ireland and Scotland have some of the best locations for edible common periwinkles.
Are Periwinkle Snails Hermaphrodites?
No, unlike many other snail species, there are distinct and separate male and female genders in the periwinkle world.
Males prefer larger females, who can produce between 10,000 and 100,000 eggs throughout their lifetimes. Females reach sexual maturity later than males, which is quite unusual. It is thought that both species are reproductively active from around 2 or 3 years of age.
How Long Do Periwinkle Snails Live?
Many snails do not reach adulthood and even fewer reach full adulthood, dying of old age. This is especially the case for shore-lurking snails that can easily get snapped up by a passing gull.
It is thought that periwinkle snails can reach up to ten years of age in perfect conditions, with five to ten years being the average.