Guide to starfish in the UK, including how to identify.
Joan Edwards, The Wildlife Trusts’ Head of Living Seas, says starfish are “Absolutely vital to their wider environment. They help maintain a delicate balance in coastal ecosystems through eating mussels and barnacles. Starfish may be weird but they are also wonderful!”
Here are Britain’s five most-spotted starfish to look out for on trips to the seaside this summer.
1. Common starfish or sea star (Asterias rubens)
Although the common starfish is usually orange in colour, it can also be brownish or purple. It is instantly recognisable from its five-armed shape, with some individuals having six arms. Starfish can regenerate missing arms – in fact they can become whole again from just one arm and part of the central body! Average size is 20cm across.
2. Spiny starfish (Marthasterias glacialis)
It is covered in three rows of spines on each of their five arms. Their whitish grey-green colour stands out even more because of the purple tip on each arm. They can grow up to a huge 80cm across but most are smaller. Average size is 30cm across.
3. Cushion star (Asterina gibbosa)
A rockpool regular, this cushion star is the smallest UK starfish. There are three different types of cushion star but this greenish-blue species is the one most likely to be found and is spottable in Devon. The average size is 3cm across.
4. Bloody Henry starfish (Henricia oculata)
Their deep pinkish-red colour gives the Bloody Henry its name, though they can be purple. Seen on the very low shore, they live on waves-swept rocky areas of the coast. Average size is 15 cm across.
5. Brittle star (Ophiothrix fraglis)
Brittle stars or ophiuroids are closely related to starfish. They crawl across the sea floor using their flexible arms for locomotion. They generally have five long, slender, whip-like arms which may reach up to 60 cm (24 in) in length.