winkles

Winkles are small marine gastropod mollusks of the family Littorinidae, commonly called periwinkles in Europe and parts of North America. The most familiar species is Littorina littorea, the common periwinkle, though several related Littorinidae are also referred to as winkles.

Description: Winkles have rounded, robust shells typically about 1 to 2 centimeters in diameter. The shell is thick, with a low to moderately high spire and a smooth, often glossy surface. Coloration varies from gray, brown, and olive to patterned with darker bands. The aperture is rounded and the shell bears an operculum that seals the opening when the animal retracts.

Habitat and distribution: Native to the northeastern Atlantic, from the Arctic to the Mediterranean, and coastal regions around Britain and Ireland; they inhabit the intertidal zone on rocky shores, thriving under rocks, crevices, and among barnacles. They are adapted to wave-exposed conditions and can tolerate periods out of water. Winkles have been introduced to parts of North America and occur along some Atlantic coasts.

Diet, ecology, and life cycle: Winkles are grazing herbivores, feeding mainly on microalgae and biofilm on rock surfaces. They play a role in controlling algal growth and serve as prey for birds and invertebrates. Most species have separate sexes and reproduce by releasing eggs and sperm into the water. Fertilized eggs develop into free-swimming veliger larvae before settling as juveniles.

Human use and conservation: Winkles are edible and have historically been harvested for food in parts of Europe and North America. They are typically boiled or steamed, with meat extracted from the shell using a pin. Overharvesting, pollution, and habitat loss can affect local populations, but winkle fisheries are often subject to regional regulation. In many places, they are more of a dietary or ecological interest than a major food source.