Kelp Forests - Scottish Natural Heritage

Kelps occur at and below low-tide level in cool temperate
regions throughout the world. They are a group of large
brown seaweeds that live on the rocky sea bed as far down
as sunlight penetration will allow. The plants often grow
together in large numbers to form dense forests, usually
composed of a single kelp species.
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Holdfasts of oarweed on rock encrusted with sponges and pink calcareous seaweed
What is kelp and
where is it found?
There are two major groups of kelps. The laminarian kelps
of the northern hemisphere, including British coastal waters,
typically have strap-like blades and a relatively short stipe. In
the South Atlantic, Pacific and Indian Oceans there is a
second category of kelps - the ‘bladder kelps’ - which have
greatly elongated flexible stipes bearing gas-filled bladders
near the top. The bladders serve to buoy up the plants to
help them make best use of surface sunlight. Both groups
of kelps are attached to the sea bed by a structure called a
holdfast. The holdfast has a superficial similarity to the root
system of terrestrial plants; however, it does not penetrate