Sand beach

They are wonderful

Suspension feeders dominate amongst the larger animals on wave exposed beaches, deposit feeders are common on the more protected beaches. It is seldom that individual animals are totally specialised - quite often they are capable of attaining food in several ways.

Food web

Because large plants often cannot survive on a beach, most of the organic material is produced by microscopic algae. Much of the organic material that organisms eat originates either from the sea or further up the beach.
    Living organisms come to the beach and are preyed upon, for example, insects, fish and plankton, but quite often food appears in the form of decaying animal and plant debris. Different beach inhabitants can then consume these sources of food in the form of free organic material, small suspended particles in the water, washed up carcasses or plants that have lost their foundation.
    Carcasses can compise of, amongst other things, jellyfish, shellfish, mussels and fish. Plant material can comprise of weed, eelgrass or seaweed. The small suspended particles can comprise of living or dead plankton, the left-overs (uneaten remains) from other animals and faeces. Soluble material can comprise of urine, mucus and organic matter that can leak out of plankton organisms in large quantities. Certain of these food sources can be temporary and uncertain, like carcasses and washed up plants. More scattered and nearly always present - at least in small quantities - are the small suspended particles and soluble material.
    Here, you can see a simplified picture of how energy and food material flow between the different organisms on a sand beach. The arrows point to the most important flows, but naturally an exchange takes place between all the ovals. The ovals even contain their own, internal food web. New organic material is created almost solely of microscopic algae. Therefore the import from the land and sea to the beach area is important.

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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