24
W.D. Heyman and B. Kjerfve
nal products from the rivers (Heyman and Kjerfve 1999). Shallow coral
flats, abundant mud bottom habitats covered with fine-grained silts and
clays, and sea grass beds represent benthic environments within the
embayment (Fig. 1.3F). Lush turtle grass (Thalassia testudinum) beds are
common but patchy in areas of high sedimentation near the mouths of the
Y cacos Lagoon and Deep River and on many submerged banks. However,
Halodule sp. tends to dominate close to the mouth of rivers (Heyman
1996). The sea grass beds are feeding grounds for numerous manatees,
which represent a portion of the Caribbean's largest population of the
Antillean subspecies of the West Indian manatee ( Trichecus manatus ). The
manatee is listed as threatened by the IUCN and listed on Appendix 1 of
the CITES convention (Auil 1998). The coastal embayment also supports
the Atlantic bottlenose dolphin (Tursiops truncatus), and may contain the
estuarine dolphin of the genus Tucoxi. Accurate identification of these dolphins by cetacean experts would represent a significant range-extension
for this largely Amazonian species. Port Honduras remains a refuge for a
few remaining endangered sawfish, Pristis pectinata.
1.3.3 Inner Cays
The inner cays are almost entirely covered by red mangroves (R. mangle).
Most of these cays are perched on surrounding carbonate banks, which are
broader in the north and northeast (Heyman 1996). The carbonate banks
are prograding towards the windward, possibly as a result of increased turbulence and oxygenation. Several of the banks exist without associated
cays. Nearly all of the banks deepen gradually to 2m and then drop sharply
into deeper waters (Fig. 1.3G). The shallow, hard-substrate banks serve a
critical role in providing habitat for corals, algae, gorgonians, and associated fauna, which cannot survive in the deeper, soft-bottom, low-light environments which otherwise dominate the basin. The mixed community of
sea grasses, algae, sponges, gorgonians, and sediment-tolerant corals provides diverse benthic habitats for a rich invertebrate fauna (115 species
minimum) from ten phyla (i.e., Mollusca, Arthropoda, Echinodermata,
Annelida, Porifera). As refuges for invertebrates, the banks serve as critical
feeding habitats for a variety of fish, including the permit, Trachionotus falcatus, which is prized as a sport fish. The banks are also critical for recruitment of juvenile lobsters (Panulirus argus), queen conchs (Strombus
gigas), and coral reef fishes.
W.D. Heyman and B. Kjerfve
nal products from the rivers (Heyman and Kjerfve 1999). Shallow coral
flats, abundant mud bottom habitats covered with fine-grained silts and
clays, and sea grass beds represent benthic environments within the
embayment (Fig. 1.3F). Lush turtle grass (Thalassia testudinum) beds are
common but patchy in areas of high sedimentation near the mouths of the
Y cacos Lagoon and Deep River and on many submerged banks. However,
Halodule sp. tends to dominate close to the mouth of rivers (Heyman
1996). The sea grass beds are feeding grounds for numerous manatees,
which represent a portion of the Caribbean's largest population of the
Antillean subspecies of the West Indian manatee ( Trichecus manatus ). The
manatee is listed as threatened by the IUCN and listed on Appendix 1 of
the CITES convention (Auil 1998). The coastal embayment also supports
the Atlantic bottlenose dolphin (Tursiops truncatus), and may contain the
estuarine dolphin of the genus Tucoxi. Accurate identification of these dolphins by cetacean experts would represent a significant range-extension
for this largely Amazonian species. Port Honduras remains a refuge for a
few remaining endangered sawfish, Pristis pectinata.
1.3.3 Inner Cays
The inner cays are almost entirely covered by red mangroves (R. mangle).
Most of these cays are perched on surrounding carbonate banks, which are
broader in the north and northeast (Heyman 1996). The carbonate banks
are prograding towards the windward, possibly as a result of increased turbulence and oxygenation. Several of the banks exist without associated
cays. Nearly all of the banks deepen gradually to 2m and then drop sharply
into deeper waters (Fig. 1.3G). The shallow, hard-substrate banks serve a
critical role in providing habitat for corals, algae, gorgonians, and associated fauna, which cannot survive in the deeper, soft-bottom, low-light environments which otherwise dominate the basin. The mixed community of
sea grasses, algae, sponges, gorgonians, and sediment-tolerant corals provides diverse benthic habitats for a rich invertebrate fauna (115 species
minimum) from ten phyla (i.e., Mollusca, Arthropoda, Echinodermata,
Annelida, Porifera). As refuges for invertebrates, the banks serve as critical
feeding habitats for a variety of fish, including the permit, Trachionotus falcatus, which is prized as a sport fish. The banks are also critical for recruitment of juvenile lobsters (Panulirus argus), queen conchs (Strombus
gigas), and coral reef fishes.