Aquascope Facts
Cliff and rocky beach ecology
The high mortality rate amongst cliff organisms during their different phases of life results in an over-production of millions of "embryoes" for every generation so that the populations can continue to exist and not became extinct. This high rate of reproduction plays an important roll in the versatility and variation of cliff fauna. Periods of low embryo mortality result in the establishment of large populations over large areas. This can be the result of e.g. increased food resources for a specific species of larva which enables them to grow quickly and transform to their bottom- living stage before they are eaten by other creatures. If they are a long-living species, they can dominate a beach for a period of several years.
   To convince yourself that the survival and development of embryoes is of great importance, you can try our calculation exmple.
    Where larve are transported, is also of importance. Independent of how many survive the plankton stage, large variations exist in the number of larvae that arrive at in the different areas.
Different areas of water contain varying quantities of larvae and it is often circumstance that decides if currents and waves carry a swarm of small larvae to a given place. Only differences in how many larvae arrive to a given place can explain why a certain species can dominate in a certain area. We know very little about the significance of spore distribution, egg fertilization and larvae to be able to determine how common a species would be on different beaches. With the aid of scientific experiments we would be able to determine how important embryo distribution is, compared to other factors like the physical and chemical conditions on the beach, competition and predation. Oystercatcher
The oystercatcher eats Marine organisms on most types of beaches.

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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