11th ICRS Abstract book - Nova Southeastern University

26.1226
Biodiversity Of Benthic Communities At High Latitudes Of The Red Sea
Moshira HASSAN* 1
1 The American University in Cairo, Cairo, Egypt
Poster Mini-Symposium 26: Biodiversity and Diversification of Reef Organisms
Most research on coral reefs of the Red Sea has focused on the Red Sea proper and the
Gulf of Aqaba, with comparatively little work published for the Gulf of Suez. The
northernmost coral reefs of the Indian Ocean were situated here at N 29.95°, where
temperatures range from less than 16°C to 30°C.
Due to its marginal setting, the Gulf of Suez has the potential to show us how coral reefs
may develop in the face of increasing stress caused by climate change and a variety of
stresses related to harbor activities and local industries.
Living and dead coral communities were surveyed from Suez to Ain Sokhna (N 29.47°)
using a combination of line intercept, point intercept and quadrat methods.
Very different benthic communities were found. Former coral reefs near Suez were
replaced by mats of the bivalve Brachidontes pharaonis, a Lessepsian migrant,
interspersed with coralline red algae and Enteromorpha sp. A layer of barnacles, found
under Brachidontes, indicates a succession after the reefs died. Several genera of live
coral, which were heavily infested by borers, were present on other patches, together with
mats of Caulerpa and Brachidontes, whereas oysters were the dominant bivalves farther
south. Reefs south of Sokhna Port were heavily populated by the sea urchin Echinometra
matthei (up to 50/m2), Drupella sp. or both, leaving large stretches of reef dead. It needs
to be investigated whether these different communities can be used as bio-indicators of
the particular stressors at each site.
Given the current developments it is unlikely that the dead reefs will recover. The
question arises whether the damaged reefs around Ain Sokhna can be saved, or whether
limited resources are better invested in trying to protect the reefs south of Ain Sokhna.
26.1227
Cryptobenthic Reef Fishes At Los Roques National Park, Venezuela.
José RODRÍGUEZ* 1
1 Biología, Universidad de Carabobo, Valencia, Venezuela
The objective of the present study was to characterize the cryptobenthic reef fishes
community associated with coral reef at Los Roques National Park. The study included
11 locations in which these cryptobenthic fish were registered using visual censuses and
some specimens were collected on SCUBA using a suction method and a fine-mesh net.
A total of 30 species in 6 families were identified (3 Blenniidae, 7 Chaenopsidae, 7
Labrisomidae, 1 Tripterygiidae, 11 Gobiidae and 1 Gobiesocidae) and 6 represented new
records in the park. The most important families (numerical abundance and species
richness) were the Gobiidae followed by Chaenopsidae. Differences were observed in the
community structure of cryptobenthic fishes between the locations, related to the reef
environment, where Acanthemblemaria medusa (Chaenopsidae), Malacoctenus
triangulatus and M. aurolineatus (Labrisomidae), were only observed at shallow reef,
environments that do not overcome 5 m of depth and dominated by the corals
Montastraea annularis, M. faveolata and Diploria strigosa. In fringing and barrier reefs,
another species were important and differentially distributed. Tigrigobius dilepis and T.
pallens (Gobiidae), Ophyoblennius atlanticus and Entomacrodus nigricans (Blenniidae)
and Enneanectes pectoralis (Tripterygiidae), were typical in the reef flat and crest,
shallow zones dominated by Acropora palmate; while Emblemariopsis sp, E. cf. bottomei
and A. spinosa (Chaenopsidae) and the gobies Elacatinus randalli, E. chancei and
Coryphopterus genus, characterized the seaward slope, below 6 m, dominated by
Montastraea genus and Colpophyllia natans. These differences probably are related to the
close association that these small fish maintain with the benthos. If we consider these
closer relations and their abundance, cryptobenthic fish structure can be use as indicators
of coral reef condition.
Key words: Cryptobenthic reef fishes, structure, Los Roques National Park, Venezuela
26.1228
Cryptofauna Associated To Montastraea Annularis’s Dead Fragments in Continental
Coral Reefs From Venezuela
Alessandra RIVOLTA 1 , Carmen RODRIGUEZ 1 , Marcos COLMENARES 1 , Jose
RODRIGUEZ* 1
1 Biologia, Universidad de Carabobo, Valencia, Venezuela
The cryptofauna associated to Montastraea annularis dead coral fragments were collected from
two coral reefs from Isla Larga, San Esteban National Park, Venezuela, in November 2006 and
March 2007. Fragments collected in the first reef located leeward of the island (AN) were
extracted at 3 and 9m deep, were the dead coral cover ranged between 40-46%. The second
reef, also leeward, was associated to a shipwreck (AA), were M. annularis was found only at
9m deep, with a dead coral cover reaching around 70%. The volume of the fragments was
estimated to standardize density values. The most abundant fauna in both reef were polychaetes
(44.06% AN; 48.78% AA), followed by sipunculids (28.7% AN; 22.22% AA), peracarids
crustaceans (11.4% AN; 15.5% AA), and bivalves (9.23% AN; 7.82% AA). Twenty-one
polychaeta families were identified, with Eunicidae, Sabellidae, Nereididae, Terebellidae y
Syllidae as the most abundant, representing 91.78% of this group. The average density was
larger in AF (545.13ind/l) compared to the AN reef (266.95ind/l). In AN reef the organisms
were significantly more abundant in fragments collected form the shallow depth (Mann-
Whitney U test p90% of the individual larvae. However,
only 25% of the decapod larvae matched adult sampled specimens, whereas approximately half
(48%) of the fish larvae matched sampled adult species. These results are not surprising as
efforts to comprehensively sample the decapod fauna were not as rigorous as those for fishes.
Nevertheless, the lack of accurate matches (