Aquascope Facts
Cliffs and rocky beach ecology

Predation and grazing

Predation is when one animal eats another, while grazing is when an animal eats algae or some other form of primary producer. Predators can have a great effect on the appearance of cliffs and rock surfaces. Shelfish, crabs, starfish, sea-urchins, fish and birds are examples of important predators and grazers along rocky shorelines. For many small animals, predation and grazing can be of importance, aswell as parasites and sickness producing micro- organisms.Sea-urchins eating kelp
This kelp forest is very sparse. This can be the result of sea-urchins over-grazing on the kelp.
It is not only the size of the population that predators and grazers effect, but also the size of the individuals, for example, larger individuals have better protection, can defend themselves effectively, so that predators do not effect them. On the other hand, small individuals can be more common within certain areas, for example because larger predators are unable to reach them in crevices.
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Cliffs and rocks are fantastic!
Zoning and flecked occurrence
Animals that are attached
Modular construction
Variation and change
Variations in water level
Wave exposure
Both cliffs and rocks
Freshwater and saltwater
Geography, climate and history
Organisms life cycles
Organisms effect on each other
Energy and the flow of material

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Bo Johannesson | Martin Larsvik | Lars-Ove Loo | Helena Samuelsson