Bladder Wrack is probably the most recognised seaweed on the shore as it is very common and grows between the low and high water marks on the rock shore. The identifiable features of bladder wrack are the paired air bladders which allow the seaweed to float when it is submerged in water. It is important to note that Bladder Wrack doesn’t have serrated edges unlike the similar species of Serrated Wrack.  

Bladder Wrack forms dense beds on the shore with other wrack species such as Egg Wrack and Serrated Wrack. These beds provide cover and moisture for other rocky shore animals and some species feed on the wrack including the Flat Periwinkle. 

Bladder wrack was once used as a source of iodine to treat goitres. Nowadays, you’re more likely to find it in your anti-ageing cream as research has found that it has anti-ageing properties!