Aquascope Facts
Cliff and rocky beach ecology
Effective grazers
The common limpet is a very effective grazer, but has became uncommon along the Swedish coastline. When they are found in large numbers, large algae has difficulting in establishing themselves. Only bladder wrack has been able to establish itself on its shell!

On protected cliffs and rocky beaches a smaller amount of alga detrius can be carried way to other areas. Predators also have a larger choice of prey as they also have access to the creatures that break down detritus material. Furthermore, there can be more grazers that attack alga which implies that more algae is produced in protected areas, but also utilized here.
Generally it appears as though detrious material collects on protected beaches, while in exposed areas it is carried away by the waves and currents. But it is clear that cliffs and rocky beaches are open systems as those periods when water does not flow past beaches are few - even on protected beach areas.Water currents transport detritus, sediment, food and larvae and many creatures pass by with their own means movement. Because of the large number of small creatures that exist in dense alga populations, many fish are attracted here to feed.

Eiders move over large areas and they eat amongst other things small crustaceans and blue mussels amongst the cliffs and rocks.

Previous page Page 51 of 52 Next page
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

Home    Contents    Inspiration    Facts    Collaboration  

© Aquascope 2000   Tjärnö Marine Biological Laboratory, Strömstad, Sweden
Bo Johannesson | Martin Larsvik | Lars-Ove Loo | Helena Samuelsson