https://vimeo.com/262618469
This is Eggwrack or Knotted Wrack (Ascophyllum nodosum)

Each individual specimen of eggwrack is either male or female.

The specimen we are looking at here is male, and you can tell this by the golden brown reproductive structure coming off the sides. These appear in Spring.

Another identifier for Eggwrack are the single dark green bladders which appear in a row along the seaweeds length.

The red seaweed you see attached, is called Wrack Siphon Weed, Polysiphonia lanosa. Another good indicator that you have the correct seaweed.

In a future video I will cover the female specimen.