This gentle giant is the largest shark in UK seas, reaching up to 12m in length. There's no need to fear them though, they only eat plankton!

Familiar as the bristly plant that easily hooks on to our clothing as we walk through the countryside or do the gardening, cleavers uses its hooks to help it climb and to disperse its seeds.

The moon jelly is the most common jellyfish in UK seas, often washing up on our beaches. No need to worry though - it doesn't sting humans.

Swifts spend most of their lives flying – even sleeping, eating and drinking – only ever landing to nest. They like to nest in older buildings in small holes in roof spaces.

Seabass is a seafood favourite, appearing on menus throughout the UK. But it's in trouble in UK seas, with much of the seabass we eat imported from European fish farms.

Sugar kelp is the crinkly belt like kelp that can often be found in deep rockpools on the lower shore or washed up on the beach after rough seas.

Did you know that there are coral reefs in the UK? UK seas are home to some amazing cold-water corals that form reefs on the seabed over 400m deep.

One of the most colourful fish in UK seas, the cuckoo wrasse looks like it belongs in the tropics. Don't be fooled though, it's very much a native species.

These globe-spanning seabirds can often be seen offshore in autumn, shearing low over the waves.

Mae'r rhywogaeth yma o forwellt yn fath o blanhigyn blodeuol sy'n byw o dan y môr, gan ddarparu cynefin pwysig i lawer o rywogaethau prin a rhyfeddol.

Ydych chi wedi gweld y twmpathau tebyg i bryfed genwair yma erioed ar draethau? Arwyddion o lyngyr y traeth yw’r rhain! Nid yw’r llyngyr eu hunain i’w gweld byth bron, ac eithrio gan bysgotwyr sy’…