Sand beach

They are wonderful

A lot of food

Swarms of life attract many creatures. Large fish, such as cod, salmon and plaice, come up from the deep and wading birds make a stop to replenish their energy supply. Birds are most active during sunrise and sunset, while fish, crabs and many other of the beaches roaming bottom living animals are most active at night.
    During the autumn, most of the shores living animals migrate to deeper water. During the stormy autumns and cold winters many die, even in many other places than on the sand beaches. Therefore, the size of the seaweed banks, and the variety of specie within, reach their peak during the autumn.


Winter ice is dangerous for the shoreline as it scrapes the shore and bottom, thus injuring the fauna that lives there. The ice also prevents, or at least impedes oxygenation of the water, water exchange at depth and many organisms can die due to the lack of oxygen. But there are small microscopic organisms, mainly diatoms, that can survive in many of the small cavities in and under the ice. These small plants can supply some small animals with oxygen during the winter.

Reasons for variations in quantity and specie

What happens to the larvae out at sea, and to adult individuals on the shore, affects population size and distribution. Far too little is known about why a specific specie is found on a certain beach, why they thrive on different parts of a beach and why populations vary.


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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