As the tide ebbs the rocks are left blanketed in layers of slippy slimy seaweed,
the marine equivalent of grasses bushes and trees. While plants on land have roots,
seaweeds instead have a holdfast. The holdfast fixes the seaweed strongly to the
rocks, however unlike roots it is not used to absorb water or nutrients.
Seaweeds come in many different shapes, sizes and colours. They can be found in
distinctive zones between the high and low water marks. Each species is adapted to
survive the particular levels of exposure, which include changes in salinity, light,
humidity and temperature found with its zone.
The easiest to identify are a family of brown seaweeds known as Wracks. They each
occupy specific zones between and once you have learnt to identify each member of the
family you can work out where you are on the shore.
Many different animals eat seaweeds, others hide amongst the fronds (or leaves)
and some live attached to them. While seaweed offers the perfect cover for seashore
animals it also has several other uses that you may not be aware of. Seaweeds are
used to help make lots of things for example ice cream, jelly, toothpaste, beer and