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Spiral wrack

Spiral wrack ©Nigel Phillips

Spiral wrack

Scientific name: Fucus spiralis
This brown seaweed lives high up on rocky shores, just below the high water mark. Its blades are usually twisted, giving it the name Spiral Wrack.

Species information

Category

Statistics

Length: up to 40cm

Conservation status

Common

When to see

January to December

About

Spiral wrack or Twisted wrack is a common wrack seaweed that grows just below the high water mark on rocky shores all around the UK. Living on the upper shore, it is very tolerant of desiccation and can survive out of the water for long periods, although not as long as Channelled wrack. It can live for up to five years.

How to identify

Twisted wrack is a pale olive-brown 'wrack' seaweed, recognised by the spirally twisting fronds with an obvious rib down the middle, and the yellowish, paired swollen tips which are the reproductive structures. It does not have air bladders and the edges are smooth not serrated.

Distribution

Common on rocky shores all around our coasts.

Habitats

Did you know?

Spiral wrack spends up to 90% of its time out of the water and can survive water loss of up to 80%. To protect itself, it curls up as it dries to conserve moisture and produces mucus to help it stay moist.

How people can help

Seaweeds provide a vital link in the food chain for many of our rarer species. Our seas and coastline are in need of protection if we are to keep our marine wildlife healthy. The Wildlife Trusts are working with fishermen, researchers, politicians and local people towards a vision of 'Living Seas', where marine wildlife thrives. Do your bit for our Living Seas by supporting your local Wildlife Trust or checking out our Action pages.