If you go down to the sea today, there’s a good chance you will find something you’ve never seen before. With more than 10,000 miles of coastline and a rich mix of habitats, the Great British seaside is the perfect place for wildlife encounters. Whether you fancy a spot of beachcombing, rock pooling, bird watching or fish following, there’s plenty to keep you busy. With a few simple pointers on where and how to look, there are hundreds of coastal species to find. Grab a pair of wellies or a wetsuit and dive mask and the British coast is all yours to explore.
Tropical lookalikes
Go for a snorkel around shallow rocks and seaweeds and keep an eye out for colourful fish that would fit right in on a tropical coral reef. Corkwing wrasse (Symphodus melops) males are usually the flashiest of their species. They can grow up to 25cm long and have gleaming green and red stripes scribbled across their faces. Their bodies are splotched in blue, red and orange.
You might spot a male picking up chunks of seaweed in his mouth and carrying them off to his expertly crafted nest. Corkwing wrasse select up to 10 different seaweed types to decorate different parts of their nests including soft seaweeds for females to lay their eggs on and encrusted pink seaweeds around the edges that act like living cement and keep growing, knitting the nest structure together.
Females are less flamboyant, although on their underside they have an electric-blue egg-laying tube. A few small males adopt a different life to the nest makers and pretend to be females with muted colours. They sneak up to nests and fertilise clutches of eggs without getting chased off by the guardian male.
Rock stars
When the tide is at its lowest point, especially during spring tides around the new and full moon, you’ll find sea creatures that can’t survive further up the shore. Peer under rocks and in damp nooks and you might see cushion stars (Asterina gibbosa), chubby little cousins of the bigger, leggier starfish that live further offshore. Powder pink and orange-coloured cushion stars are often fingernail size but they can grow up to 5cm across. They’re common all along the British coast (though you’re unlikely to spot one in the east between Lincolnshire and Hampshire).
Also, on the underside of rocks at low tide, look out for what look like constellations of tiny golden stars. These are star ascidians (Botryllus schlosseri), colonies of little animals known as sea squirts. Between three and 12 individuals make a single star-shaped pattern. Sea squirts start life as minute larvae that swim through the water. When they find a rock to settle onto, they digest their simple brain and nerve cord and spend the rest of their lives sitting still filtering water through their bodies.
Once you’ve finished looking, always carefully put the rocks back the way you found them.
Cuttlefish and catsharks
High up on the shore, beyond the reach of the water, you will find traces of animal life the sea has left behind. Bone white objects like miniature styrofoam surfboards are the internal shells of common cuttlefish (Sepia officinalis), relatives of squid and octopuses. Cuttlefish live all around the British Isles as deep as 200 metres, and large numbers gather along England’s south coast.
You might encounter living cuttlefish underwater while diving and snorkelling. Look for them in seaweed gardens and around rocky reefs. They can grow as long as your arm and have a skirt-like fin that flutters all the way around their oval body. Their big eyes have W-shaped pupils. Their skin can swiftly change colour and texture; one minute they’re brown and bumpy matching the seabed, the next they’re smooth and pale with black zebra stripes.
One way to distinguish cuttlefish from octopuses is to count their appendages: octopuses have eight arms with suckers all the way along, meanwhile cuttlefish have eight arms plus two tentacles that shoot out and grab prey with suckers just at the end.
Other strandline objects to spot are the leathery egg cases, also known as mermaid’s purses, laid by sharks and skates. Small-spotted catsharks (Scyliorhinus canicula) lay small egg cases, 5-7cm long, with curly tendrils in each corner that help fix them to seaweed on the seabed. After six to nine months, a miniature, fully formed cat shark wriggles out and swims off. Divers have a good chance of encountering adult catsharks resting on the seabed. Their slender, brown-speckled bodies grow to about a metre long, and they have oval-shaped eyes, like a cat.
Jewel-like shells
While snorkeling or exploring the shore at very low tides, look for little jewel-like shells, with shining turquoise stripes, sitting on the rubbery blades of kelp. Blue-rayed limpets (Patella pellucida) are seaweed-eating sea snails and they graze little dimples in the kelp to create space to nestle in.
Their glowing stripes selectively reflect blue wavelengths of sunlight, thanks to the intricate nanostructure of the shell’s interior. Material scientists are looking into recreating this effect to make transparent display screens. Blue-rayed limpets don’t live along much of the east coast of England, but you can find them all around the west and northern coasts of Great Britain and Ireland.
Atlantic puffin
There’s no mistaking a puffin, with its black and white body, rainbow-coloured, parrot-like beak and stubby wings which it uses both to fly and swim while hunting for fish, using its feet as a rudder. It can dive to 40m, hold its breath for a minute and cram dozens of sandeels in its beak at a time.
Puffins spend the wintertime far out at sea. Then, in spring and summer, around four million pairs fly to the UK to breed. Look out for puffins dashing in and out of their burrows on cliffs around Scotland, northern and south-west England and Wales.
Skomer Island off the Pembrokeshire coast is one of the best places to see puffins, with more than 40,000 counted each year. The seas around Skomer are well protected from overfishing and the island is free of predators, so puffins get plenty of food and seclusion to rear their chicks. Elsewhere, the seabirds are suffering because the climate crisis and overfishing are making it difficult for them to find enough food.
• The headline of this article was amended on 28 June 2024. A previous version had “catfish” instead of catsharks.
