IDA002: Brown Algae

Brown algae inhabiting rocky shores live in distinct "zones" which are identified (mainly at least) by the height of the shoreline. Species inhabiting the upper zone have to be able to cope with stresses such as desiccation and variable temperatures, while those on the mid-lower shore have to be able to cope with the effects of wave action and competition from other species for example.

This image shows 6 common brown seaweeds and the zones they are commonly found in. They are:

(a) Pelvetia canaliculata (Channel Wrack)
(b) Fucus spiralis (Spiral wrack)
(c) Fucus vesiculosus (Bladder wrack)
(d) Ascophyllum nodosum (Knotted wrack)
(e) Fucus serratus (Serrated wrack)
(f) Kelp (Laminaria digitata)

Knotted wrack is typically only found on sheltered shores.

For an alternative presentation, see image IDA003.