Fringing reefs in deeper waters (>5 m) have so far been described
primarily for the west coast. They are generally found where the
island shelf is "wider". For Dominica's west coast this
means approximately 200 - 500 m. None of these reef systems reach
the surface and so the reef flats remain in 12-8 meters. Lagoonal
settings or fringing-lagoon reefs are absent.
The
largest and best developed representative of this reef type (approximately
2.6 km long) is found along the west and southwest-facing contour
of the shelf lining the Grand Savane area. It is architecturally
diverse, with a high species richness and extensive live benthic
cover of sponges, soft corals and hard corals. Local dive sites
within this reef system include Lauro Reef, Rena's Reef and several
other sites in between these two. The reef flat and the fore reef
are the most appealing visually and in their diversity. Erosional
sand chutes exist, these are often lined with massive framework
builders such as M. annularis and M. faveolata.
Intermittently, towards shore, the reef flat gradually transitions
into sandy environments characterized by a variety of primary
hard substrates originating from cliffs, beaches, and rivers,
all of which form the stable substrate for sessile organisms.
See "OTHER CORAL HABITATS".
The
northern-most section of this system, within approximately 500
and 150 m from the mouth of the Batali River, is characterized
by a series of linear reefs, oriented perpendicularly to shore,
in waters between 10 and 30 meters depth. Although not connected
these individual reefs are aligned like a spur and grove system.
Mero
harbors the second largest such system along the West coast but
with a substantial contribution of primary hard substrates in
5-10 meters depth. This region is also characterized by mixed
sea grass beds and large (500 m2 +) mono-specific coral assemblages.
See OLIGOSPECIFIC ASSEMBLAGES
.
Besides
these two locations, true fringing reefs in deeper waters (with
coral accretion) are virtually absent along the west coast.
SCCS1106