Identifying common seashells on British beaches

The best time to hunt for seashells on a British beach is the hour or two either side of low tide, when the sea has drawn back and left its latest haul along the strandline. Spring tides, around the new and full moon, expose the widest stretch of sand, and an onshore blow will often throw up a fresh crop of shells that were sitting offshore only hours earlier. All you really need is a sharp eye, a willingness to crouch down, and a little patience.

The strandline: where the shells collect

Walk to the top of the beach, just below the dunes or the sea wall, and look for the dark ribbon of debris marking the last high water mark. This is the strandline: a tangle of kelp, bladderwrack, crab moults, cuttlebone and, if you're lucky, whole shells rather than fragments. Work along it slowly rather than striding past. Intact specimens tend to gather in dips and hollows where the water slows, and where a rocky outcrop breaks the current's energy. Crouch down, turn things over, and look at each shell from more than one angle before deciding what it is.

Cockles: plump, ribbed and heart-shaped

The common cockle is one of the easiest shells to recognise. Hold one on its side and you'll see a rounded, faintly heart-shaped outline, with two valves meeting along a toothed hinge. The surface carries strong radiating ribs — usually between twenty and twenty-eight — running from the hinge to the outer edge. Colour ranges from creamy white and pale yellow to light brown, and older shells often look bleached or stained. Full-grown cockles reach four to five centimetres across.

Cockles favour sandy and muddy shores, especially estuaries and sheltered bays, so you'll often find them in great numbers where the sand is soft underfoot. If both valves are still joined, shake the shell gently: a faint rattle usually means it has been empty a while.

Winkles: small spires in their thousands

Winkles, or periwinkles, are the little spiral shells clustering on rocks and in pools at low tide. The common winkle has a neat, conical shape with a pointed spire and a smooth, slightly glossy surface marked by fine spiral lines. Colours run from dull grey and brown to almost black, often with faint darker bands. They rarely exceed three centimetres. The flat winkle, found in similar places, is squatter and often brightly coloured — yellows, oranges, reds and greens can all appear in the same population.

Living winkles clamp onto rock and seaweed, sealing the opening with a horny trapdoor called an operculum. Loose shells on the strandline are usually empty ones, and you'll often find the operculum nearby: a small flat spiral that looks rather like a tiny ammonite.

Scallops: the fan-shaped show-offs

Scallops are the shells most people picture when they think of the seaside. The great scallop is large and fan-shaped, up to fifteen centimetres across, with bold radiating ribs and two flat "ears" either side of the hinge. Colours vary enormously: cream, orange, brick red, pink and occasionally purple, often with paler bands and growth rings. The queen scallop is smaller, five to seven centimetres, rounder in outline, with finer ribs and a prettier palette of reds, oranges and creams. Scallops live on the seabed, so finding a whole one on the beach usually means a storm has done the work for you. Check the hinge: an intact ear on both sides is a good sign the shell is complete.

Other shells worth knowing

• Mussels — smooth, blue-black and wedge-shaped, with faint growth lines, usually found in clumps on rocks.
• Razor shells — long, thin and brittle, up to twenty centimetres, shaped like a cut-throat razor handle and often found in fragments.
• Slipper limpets — small, white and curved, with a little internal shelf, sometimes stacked in chains on other shells.
• Oysters — rough, irregular and layered, with a chalky interior and a faint purple or greenish sheen inside.

Shell-hunting habits worth keeping

Check the tide tables before you go, and never let a promising shell distract you from the returning water — British tides can move faster than you expect across flat sand. Wear something with grip, as strandlines are often slippery with weed. Take a small bag or tub if you want to collect, but leave live animals where they are and don't disturb rock pools more than necessary. If you're unsure whether a shell is empty, look for a resident: a hermit crab, a small fish, a winkle. Photographing your finds and leaving them behind is a fine habit too.

Learn the shape first, then the colour, then the texture, and before long you'll be able to name most of what the tide hands you.