Intertidal Habitats
 
 

Sandy shores

 
 

Sand beaches are common throughout the Sanctuary and range from the exposed shores along the northern coast of Abu Ali to the more sheltered beaches lining the bays of Dawhat ad-Dafi and Dawhat al-Musallamiya.

 
 

The animals living in this habitat seek protection from the sun and air whilst the tide is out by burrowing and therefore the beaches often appear to be without life at low tide. However, on closer inspection it is possible to recognise a zonation pattern across the beach from high to low tide with each level marked by the burrows of a particular species.

 
 

Above the highest tides, the dunes are colonised by beach grasses. At the top of the beach the male ghost crab constructs conical sand towers during the breeding season to advertise its presence.

 
 
Sheltering under the weed and damp debris left behind by the last high tide is a community of beetles (37), flies, amphipods (38) and isopods (39). Some of the animals, such as amphipods (sand hoppers), may burrow into the sand and can be found by digging below the small holes they leave. Tiger beetles fly above the sand searching for prey.
 
 

At a slightly lower level, where the sand is smoothed by the last high tide, small holes surrounded by radiating lines of sand pellets mark the presence of a small deposit-feeding crab (40). On sheltered shores, shells of a large white bivalve mollusc are very obvious. Live specimens occur just below the sand surface over much of the mid intertidal zone. Although not visible, several hundred species of molluscs and polychaetes occur beneath the intertidal sand, these together with crabs form a food source for many waders and shorebirds including the crab plovers (41) and Kentish plovers (42).

 
 
Where the sand surface is wet and highly salty, large numbers of small snails with conical shells are found grazing on the small algae between the sand grains. Digging at this level on the beach you might find razor shells (45); however, as they can feel the vibrations of your footsteps they normally disappear quickly down into the sand to hide. When the tide returns these animals will extend two tubes, called siphons, to the sand surface; water is drawn down across gills where food and oxygen are removed and then passed out. The lower tide level is characterised by polychaetes (43) and shells (44). At very low tides, seagrasses may be exposed.
 

 

click on the list below to see some more inhabitants of sandy shores

Tiger beetle
Sand crab
Ghost crab and Ghost crab burows on a sandy beach
Grazing snails
Seagrass
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