Field Guide to Seagrasses of the Red Sea - Seagrass-Watch

Intertidal
Some seagrass meadows are
periodically exposed to air partially
or completely depending on the
tide.
Subtidal
In the subtidal zone, seagrass
meadows are covered completely
by water even at the lowest tide.
The abundance and distribution of seagrasses are influenced by wave action.
Strong wave action can erode seagrass meadows or inhibit colonization of
unoccupied habitat. Therefore, seagrass meadows in the sheltered side of a
headland and in bays (refer to photographs below) often differ in abundance
and diversity to meadows found in locations exposed to stronger wave
action.
Animals can also influence the abundance and distribution of seagrasses.
Snorkeling on corals reefs fringing the Red Sea coastline will reveal a ‘halo’
of bare sand between the reef and seagrass meadows. This area of sand
remains free of seagrasses due to sea urchins and other animals that leave
the reef to feed on these plants at night. Dugongs and stingrays can disturb
seagrass meadows while feeding. Burrowing shrimps can also effect
meadows by depositing sediment on top of seagrasses located adjacent
to their burrows.
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