Mangrove, Avicennia marina,
swamps occur at several localities along the coastline
of the Red Sea becoming more frequent and extensive,
with larger trees the further south they are. The most
northerly stand of mangroves in the Red Sea is found
about 26km north of Hurghada at el-Gouna. The most extensive
stands are found between Bir Shalatin and Halayib, where
uninterrupted mangrove forests extend for several kilometers
fringing the coastline. South of latitude 23 degrees
N another species of Mangrove, Rhizophora mucronata,
begins to appear but it never becomes as abundant as
Avicennia marina within Egyptian boundaries.
The mangrove grows as a shrub or small tree to 1-3m
high. It is uniquely suited to the severe, saline, oxygen-depleted
habitat in which it grows and has evolved several strategies
to cope. It is usually surrounded by erect stem-like
growths called pneumathodia that arise from
the roots and are thought to provide oxygen for them.
The seeds germinate while still on the plant and send
out embryonic roots, thus avoiding the necessity of
germinating in the extremely saline soil and gaining
oxygen at the most important time of germination. A
third adaptation is the plant's ability to absorb saline
water and excrete the salt on the leaves, which become
covered with salt crystals.
The mangroves are vital components of the coastal ecosystem and contribute significantly to the health of the environment as well as providing spawning grounds and havens for many commercially important species of fish and crustaceans.
A number of birds breed in this habitat among them the Striated Heron, Ardeola striata, the Spoonbill, Platylaea leucorodia, Reef Heron, Egretta gularis, and occasionally the Osprey, Pandion haliaetus, although the Osprey more often nests on the ground.
Other salt
marsh vegetation types are not particularly
common along the coasts of the Red Sea and the Gulf
of Suez. Those at el-Ain el-Sukhna and the deltas of
Wadi el-Gemal and Wadi el-Diib constitute the most significant
salt marshes of the Egyptian Red Sea littoral.
Wadi el-Gemal runs into
the Red Sea about 30km south of Mersa Alam. Close to
the shore there is a flowing freshwater spring; the
water from which has blended with seawater to form a
low-salinity marsh covering approximately 500m².
Round the spring there is marsh vegetation of reeds,
Phragmites australis and Juncus spp.
Slightly upstream, Tamarisk trees are abundant together
with other salt-tolerant plants such as fleshy-leaved
Zygophyllum spp., which form spreading or cushion-like
ground cover.
The Cape Hare, Lepus
capensis, and the Lesser Egyptian Gerbil, Gerbillus
gerbillus, are both found here as well as Dorcas
Gazelle Gazella dorcas. The Semaphore Gecko,
Pristurus flavipunctatus, is common in coastal
Tamarisk thickets. However, it does not appear that
any animals are specific to this type of habitat
Intertidal zones, where the sea and the shore meet and overlap, form valuable habitats for shoreline creatures and often harbor a fascinating variety of shallow-water life forms. These include animals that are well suited to living both underwater and out of water entirely. Often, at low tide, there are tidal pools in which creatures can survive very well until the tide rises and covers the zone again.
Some species of crustaceans,
such as shrimps and crabs, and other invertebrates
are adapted to this particular lifestyle. Barnacles
are among the best adapted of the crustaceans although
some species are more tolerant of heat and desiccation
than others. The barnacle has been described as "a
crustacean, which stands on its head and kicks food
into its mouth with its hind legs." Occasionally,
a fish gets stranded in a tidal pool and is at risk
of becoming easy prey for a hungry sea bird. On stony
beaches smaller invertebrates are able to hide under
rocks for protection from predators.
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