Gutweed gets its name from its intestine-like appearance! It has long fronds which are filled with bubbles of trapped air along its length giving it a wiggly appearance! The fronds are usually unbranched and bright green in colour. Gutweed is a common seaweed in Ireland and can be found on most coastlines in various habitats such as rockpools, sand and even on other seaweeds and shells. 

Gutweed can form large masses on the rocky shore or, if detached, floating in the sea. Its ability to form these masses is an important feature for other smaller creatures on the shoreline as the gutweed provides shelter and protection. Many invertebrates and small fish also feed on gutweed.

Gutweed reproduces quickly and can be responsible for water bodies having a green tinge as it releases lots of green reproductive cells!