11th ICRS Abstract book - Nova Southeastern University

10.303
Effects Of Coral Spat Characteristics On Post-Settlement Survivorship
Yoko NOZAWA* 1
1 Biological institute on Kuroshio, Otsuki, Kouchi, Japan
Poster Mini-Symposium 10: Ecological Processes on Today's Reef Ecosystems
Scleractinian coral spat have various characteristics consisting of a combination of
several parameters, e.g. initial size, polyp size, growth rate (i.e. spat size), budding rate,
and presence/absence of zooxanthellae at settlement. These different characteristics of
coral spat apparently affect post-settlement survivorship. Understanding of which
parameters are most important in influencing post-settlement survivorship should have
significant ecological and evolutionary meaning for scleractinian coral species. The
objective of this study is to examine the effects of coral spat characteristics on postsettlement
survivorship, focusing on the above five parameters. The study was started in
summer 2007 at Nishidomari, Kochi, Japan (132°44′, 32°46′), and is planned to continue
for one year. Spat of nine coral species were obtained from July to August, 2007;
Acropora japonica, Acropora solitaryensis, Echinophyllia aspera, Favites abdita, Favites
pentagona, Favites russelli, Platygyra contorta, Pocillopora damicornis, Stylophora
pistillata. Spat characteristics of these species are largely grouped by the five parameters
as follows; (1) initial size: small (0.16-0.39 mm2 in average: Ea, Fa, Fp, Fr, Pc), large
(0.59-4.56 mm2: As, Aj, Pd, Sp), (2) polyp size of each species: small (ca. 1 mm diam.:
As, Aj, Pd, Sp), large (5-15 mm diam.: Ea, Fa, Fp, Fr, Pc), (3, 4) growth and budding
rates: slow (Ea, Fa, Fp, Fr, Pc), fast (As, Aj, Pd, Sp), (5) presence of zooxanthellae: yes
(Pd, Sp), no (As, Aj, Ea, Fa, Fp, Fr, Pc). The spat settling on one side of tiles (10 x 10
cm) were mapped and photographed under a stereomicroscope at the start of experiments.
Four to six replicate tiles per species were fixed to rock vertically at 5 meters depth. The
tiles were retrieved to measure survival and size of each spat monthly for the first three
months, and then every three months. Here I will discuss the results from this study.
10.304
High Recruitment Of Hard Corals At Archipiélago Los Roques National Park,
Venezuela
Adriana HUMANES* 1 , Carolina BASTIDAS 2
1 Laboratorio de Comunidades Marinas y Ecotoxicología, Universidad Simón Bolívar,
Caracas, Venezuela, 2 Departamento de Biología de Organismos, Universidad Simón
Bolívar, Caracas, Venezuela
Los Roques National Park (LRNP) is a marine protected area of exceptional ecological
value because of the high-quality of its coral reefs with respect to species diversity and
coral live cover. At this protected area, reef builders such as acroporids that have suffered
decline during the past three decades are showing signs of recovery. Recruitment is one
of the main processes that can determine patterns of recovery, distribution and
abundances of corals in this area. To evaluate the effects of settlement and early survival
of hard corals on the potential of recovery of LRNP, 120 unglazed terracotta tiles of
25x25 cm were deployed horizontally, between 3 and 5 m deep, and directly over the
substratum at four reefs. A visual survey of the lower side of each tile was made with a
binocular dissecting microscope to quantify and identify hard coral settlers. The position
of all coral recruits in the tiles was mapped in each survey and they were identified to the
lowest possible taxonomic level. Preliminary results showed high recruitment (between
39.12 ± 31.09 and 395 ± 660.19 recruits per m2 per month) and high survival rates after
one month (38.75 – 68.75 %) in comparison to other Caribbean reefs, emphasizing the
importance of this protected area. Furthermore, survival rates were lower at the two sites
nearest the populated island, suggesting that the implementation of additional
management strategies could benefit corals and other reef species.
10.306
Spatial Variation in The Distribution Of Initial And Terminal Phase Parrotfishes At
Fernando De Noronha Archipelago, Northeastern Brazil
Roberta BONALDO* 1
1 Australian Research Council Centre of Excellence for Coral Reef Studies and School of
Marine Biology, James Cook University, Townsville, Australia
Parrotfishes (Labridae, formerly Scaridae) are herbivorous reef fishes with complex sexual and
social systems. Most parrotfish species are protogynous hermaphrodites that change color and
sex when adults, from initial phase (IP) females or males to terminal phase (TP) males. The
distribution of IP and TP individuals of three Sparisoma species was studied at Fernando de
Noronha, an oceanic archipelago off Northeastern Brazil. Visual censuses were conducted on
five reefs on the main island and six sites on secondary islands of the archipelago. In the main
island, IP individuals of the three species were more abundant than TPs, but in the other study
sites TP individuals were found in similar or higher numbers than IPs. In sites where IP
individuals were more abundant, TPs were found swimming constantly, apparently patrolling
territories and chasing away conspecifics. In contrast, in reefs were the relative abundance of
TPs was higher, these individuals were predominantly found on feeding activities. Thus, TP
individuals of the studied species seen to have different behaviors according to the site, which
probably drive the differences on relative abundances of IP and TP individuals around the
archipelago. These results are similar to the distribution pattern of Sparisoma viride in the
Caribbean, and emphasize the complexity of parrotfishes’ social systems, especially Sparisoma
spp. The marked variation on the abundance and behavior of different Sparisoma species
highlights the importance of considering not only species abundance, but also intraspecific
behavioural patterns when formulating management strategies on reef ecosystems.
10.307
Spatial Variability in The Community Structure Of Juvenile Corals in La Parguera,
Southwestern Puerto Rico
Emmanuel IRIZARRY-SOTO* 1 , Ernesto WEIL 1
1 Department of Marine Sciences, University of Puerto Rico, Lajas, Puerto Rico
Juvenile coral abundances and community structure have been shown to be variable at spatial
and temporal scales. Recent studies have shown that small spatial scales play important roles in
the abundance and community assemblages of juvenile corals. In this study abundances and
community structure of juvenile corals were evaluated using a nested ANOVA design to assess
the spatial scale at which variability was higher. Six reefs were surveyed across the insular
platform off La Parguera, southwestern Puerto Rico in an inshore-offshore gradient. All
juveniles were counted and identified to at least genera in six randomly placed 1m2 quadrats in
each of four 20m long transects in each of four depth intervals (0-3, 4-10, 10-15 and >15m) in
four of the six reefs, and a deep habitat (>15m) in the two offshore reefs. Mean overall density
of juvenile corals was 1.53 ± 0.11 col/m2 with only 38 % of the variability explained by habitat
(depth) and 52 % by factors not evaluated. Juvenile coral densities increased from 0.5 ± 0.11
col/m² in shallow habitats to 2.78 ± 0.39 col/m2 in intermediate depths. Shallow juvenile
communities were dominated by Diploria strigosa while intermediate and deep habitats were
dominated by Montastraea cavernosa, M. faveolata and Stephanocoenia intersepta (Bray-
Curtis). Results indicate that medium to small spatial scales (