Sand beach

They are wonderful


Competition can regulate where and which organisms live on a beach. For competition to exist there has to be a resource that is insufficient and in demand. Larvae can, for example, find it difficult to find a space to inhabit. At the same time they run the risk of being consumed by filtering feeders. Even if they manage to reach the bottom uninjured and find a free spot to habitat, they will as they grow in size need more space. All creatures that manage to find a free space on the bottom one year, will probably have problems later when they became larger and are competing for space.

Experiments on the beach

Competition can result in that individuals of different specie cannot cohabitat the same depth on sedimentary bottoms. Field studies have shown that when one specie has been taken away, another has taken over and increased it sphere of habitation. This indicates that competition between the specie really has caused a segregation according to depth.
    Competition between the specie on soft bottoms is probably less than on cliffs and rocks (hard bottoms) because of greater bredth, width and depth and because bottom sediment gets mixed up sometimes. This makes it difficult for one individual to "grow over"
another and cover it, which can happen on hard bottoms.


Predation is when one animal eats another and is regarded as the most important Biological factor that regulates the size of populations and variety of specie on sand beaches.



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Waves, bottoms and construction

Sand movement and erosion

Sand bottoms as living environments

The art of digging

Sand beach organisms

Food web

Change and variation

Swedish beach life

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