Snorkelling Britain

Spying conger eels hunting in the dusk, watching the sunrise through sea arches, or floating in the water, immersed in the miniature world of sea slugs: we’ve been snorkelling around Britain for the past 20 years and every time we go out, we find ourselves marvelling at the scale, beauty and complexity of our oceans.

The UK’s high tidal range and strong Atlantic currents bring warm, nutrient-rich water to our shores, making the British coastline one of the world’s most dynamic marine habitats.

Seeing beneath the surface

There’s no single best way to spot marine life. A dusk snorkel might reveal nocturnal hunters such as cuttlefish and squid drifting through the shallows. A torch shone into a dark overhang might reveal a crab, lobster or conger eel. Rocky cracks and crevasses shelter smaller creatures – blennies, prawns and anemones – tucked out of reach of predators.

Sometimes, the life isn’t on the seabed at all: study the water around you for tiny, otherworldly comb jellies and other minuscule creatures.

The best sighting will come after settled weather, which improves ‘viz’ (visibility). Viz is also affected by algae blooms which tend to occur between April and August.

A wetsuit helps extend time in the water; fins add distance and make it easier to dive. A tow float or swim buoy increases surface visibility – useful when your head’s down and attention elsewhere, making it harder to see or be seen by passing boats.

Habitats to explore

Seagrass Meadows: Found in sandy shallows, these gentle swaying beds provide a home to crabs, snakelocks anemones, juvenile fish and sea slugs. Try Swanage in Dorset, Gruinard Bay in Wester Ross and Porthdinllaen on the Llyn Peninsula, North Wales. A hugely important species in the fight against climate change, seagrass meadows are being cultivated and protected around our shores.

Kelp Forests: Dense, towering underwater forests that are full of life – look for fish darting amongst the foliage and tiny sea slugs adorning the fronds. Great Bay in the Isles of Scilly and Staxigoe Harbour in Caithness are a couple of our favourites. Recognition of the pivotal role which kelp plays in promoting marine biodiversity and carbon capture has led to a number of restoration projects cropping up around our shores. Take a look at the Sussex Kelp Restoration Project for a good news story on this front.

Rocky Reefs: Rocky reefs provide the stable footing for seaweeds which, in turn, enable complex marine ecosystems to develop. Visit Killiedraught Bay in the Scottish Borders, Lamorna Cove on the Cornish coast, or Kimmeridge in Dorset to spot reef inhabitants such as anemones, starfish, squat lobsters and resting blennies.

Man-made Structures: Piers, pilings and wrecks act as artificial reefs: static species like mussels and anemones cling to them and fish gather in their shallows. The wreck of The Minx near Weymouth, The Juanita in Orkney and The Landing Jetty on Lundy are good examples.

Sandy Seabeds: Less obvious, but full of hidden life. Flatfish and sand gobies blend in so well they’re easy to miss until they move. Visit Galmisdale Bay on the Isle of Eigg or Boggle Hole in North Yorkshire for some shallow water spotting.

Who lives here?

Scared of what lies beneath? Fear and fascination aren’t so far apart: in our experience, learning about marine life is the secret to loving it.

Tides shape what is seen. At high tide, you’re snorkelling in the high intertidal zone, home to mobile species or hardy intertidal life that can tolerate exposure to air and sun. At low tide, you move through the subtidal zone, where colourful anemones open and you can explore the habitats created by the light-hungry seaweeds anchored to the rocks below.

Stay aware of water movement – currents can quickly take the unaware away from shore. Check tide times (BBC or local charts) and conditions before setting out and keep an eye on landmarks to stay aware of your position.

The quieter the swimmer, the more is revealed: take your time, avoid splashing and fast movements and use occasional leg or fin strokes to propel yourself forward to avoid scaring away the more introverted underwater creatures. Some of the most memorable encounters happen without going far. Snorkelling, when done well, is the art of staying still.

 Fear and fascination aren’t so far apart: in our experience, learning about marine life is the secret to loving it.

Lesser Sand Eels: These small silvery fish are found in large shoals over shallow, sandy seabeds during the summer and are common all around the British coast. They form an essential food for seabirds and other fish species.

Common Blenny or Shanny: Typically found in rock pools or shallow water, the shanny can also survive out of water between tides by hiding under damp rocks or seaweed. Underwater, they are usually seen resting on sandy or rocky surfaces, coolly observing the goings-on around them.

Two-Spotted Goby: Often found in small groups around seaweed-covered rocks, the two-spotted goby is a common sight along all coasts of Britain. Despite the name, only the male has two spots; the female has a single spot at the base of the tail fin.

Long-spined Sea Scorpion: Difficult to spot due to their impressively irregular outline, mottled patterning and chameleon-like ability to change colour to blend in, the long-spined sea scorpion can be found all around Britain, usually hiding on rocky ground and amongst seaweed. Despite their alarming name, they don’t sting.

Common Shore Crab: A medium-sized crustacean, ordinarily green in colour but sometimes orange or red. Another transient occupant of the intertidal zone, the shore crab can be found in rock pools or shallow water at all states of the tide. They are very common around the British coast.

Common Prawn: These small, translucent prawns are often found hiding under rocks or on sheltered ledges, scavenging for food and greedily consuming almost anything they come across.

Beadlet Anemones: Glossy, red or rust-brown domes commonly seen by rockpoolers clinging to rocks and ledges, Beadlet anemones are a common shallow-water species. They retract their tentacles for protection when above the waterline. When viewed underwater, they can be seen feeding, using these tentacles to sting and catch prey.

Snakelocks Anemones: A beautiful and common sight on Britain’s southern and western coasts, especially in tidal pools, snakelocks anemones don’t extend far into the subtidal zone. Recognisable by their long, light-brown or purple-tipped green tentacles.

Spiny Starfish: Much larger than their common cousins, spiny starfish measure 30cm across, though some can reach up to 70cm. They are grey-green with a covering of purple-tipped white spines and are commonly found on Britain’s south and west coasts, with some sightings on the east coast.

Sea Hare: Although they resemble slugs, sea hares are technically snails due to their internal shell. They feed on seaweed and vary in colour from green to reddish brown, depending on their food source.

Seaweeds

There are over 600 species around the British coastline, from delicate purple laver to broad, leathery kelps. If you have only ever seen seaweeds washed up on the tideline or exposed at low tide, prepare to be surprised by the beauty they take on underwater.

See the Seaweed Field Guide for a visual guide to distinguishing your thongweed from your dabberlocks.

More ways into snorkelling

• Snorkel trails – designated routes through shallow water where snorkellers can follow a marked or guided path – have been established in Scotland (including Argyll, the Isle of Arran, the Berwickshire Coast and the North West Highlands), as well as in Kimmeridge Bay in Dorset and the waters around Jersey.
• Guided snorkel tours help you learn the basics while introducing you to the local marine life. Many organisations, including The Wildlife Trusts, offer expert-led experiences.
• Snorkelling Britain: 100 Marine Adventures (Emma & Gordon Taylor, Wild Things Publishing) is available from The OSS Shop and Wild Things Publishing. (We earn a small commission when you click through to Wild Things Publishing using this affiliate link and make a purchase. This does not affect our editorial independence and integrity.)
• For those keen to build confidence and skills, snorkel training is available through local SCUBA clubs, many of which are part of the British Sub Aqua Club (BSAC). Courses typically teach you how to choose kit and read conditions. Bespoke advice on how to get started is available if you email: snorkelling@bsac.com.