11th ICRS Abstract book - Nova Southeastern University

Poster Mini-Symposium 10: Ecological Processes on Today's Reef Ecosystems
10.256
Effects of Alternate Coral Reef States On Attraction, Settlement And Subsequent
Survival Of Marine Invertebrate And Fish Larvae
David LECCHINI* 1 , Pascal DUMAS 1 , Suzanne MILLS 2 , Eric PARMENTIER 3 ,
Bernard BANAIGS 4 , Dominique PONTON 1
1 IRD, UR 128 CoReUs, Noumea, New Caledonia, 2 EPHE, Perpignan, France,
3 University of Liege, Liege, Belgium, 4 INSERM University of Perpignan, Perpignan,
France
Biodiversity is declining, and habitat degradation is now commonplace. Coral ecosystem
degradation is usually characterized by coral mortality from natural and anthropogenic
stressors. This decrease in coral cover causes a substantial increase in macroalgal cover
which, in turn, limits the recovery of coral populations and thus modifies fish and
invertebrate communities. Thus, areas experiencing perturbations often exhibit declines
in adult populations, leading to a higher rate of species loss than in pristine habitats, and
the persistence of species in the area becomes reliant on the rescue effects of recruitment.
Yet, we do not know if the decline of marine organisms is due to increased mortality of
adult reef organisms or due to a decrease in the degraded reef's recruitment potential,
which could decline if 1) its properties have changed sufficiently to decrease its inherent
attractiveness to planktonic larvae; 2) larval ability to locate preferred microhabitats has
decreased; or 3) newly settled individuals' ability to survive to recruitment has decreased.
We will test the effects of alternate reef states on the attraction, settlement, and
subsequent survival of marine invertebrate and fish larvae. We will present the first
results acquired in French Polynesia (ANR Project and CRISP Program). For example, a
series of laboratory, in situ and biochemical experiments was conducted to test how
marine larvae respond to water-borne chemical cues originating from different reef states
(degraded vs un-degraded habitat). This was followed by testing if the auditory signals
originating from different reef states impact the selection of reef state by fish and
invertebrates larvae.
10.257
Abundance, distribution and taxonomic composition of juvenile scleractinian corals
in coral frameworks at the Islas del Rosario archipelago, Colombian Caribbean
Tomás LÓPEZ* 1 , Raúl NAVAS-CAMACHO 1 , Diego L. GIL-AGUDELO 1
1 INVEMAR, Santa Marta, Colombia
This study aimed to evaluate the juvenile coral community structure in Islas del Rosario,
one of the most important coral reefs in Colombia that nowadays is showing signs of
deterioration. Census of abundance and taxonomical identification of juvenile corals were
carried out in eight zones with coral frameworks, assesing two depths using sampling
bands of 30m2. Depth, reproductive strategies, non-juvenile coral community structure
and mortality rates of juvenile corals were factors included in this study in order to
analyze their relation with the juvenile community found. A total of 2622 juvenile corals,
belonging to 18 taxa, were recorded, of which Agaricia spp. and Porites astreoides, being
brooders or planulators, were the most abundant. Those taxa including massive species,
generally spawners, showed low abundance, being infrequent at juvenile stage. Taxa
richness and density of juvenile corals were considered low. Depth did not significantly
affect juvenile coral densities; even though, it did influence the community structure
since patterns of zonation of the communities sampled, were found in accordance with
this factor. Positive correlation between juvenile and non-juvenile densities was found
according to depth and reproductive strategy. Coral juvenile structure could be indicating
a phase shift in the coral communities of Islas del Rosario Archipelago, in which massive
long-living corals which presented lower juvenile densities, seem to be replaced by corals
with short-living strategies which showed numerous juveniles. Mortality found could be
reflecting that previous events to recruitment determine in a broader way the coral
community structure in the Archipelago.
10.258
Coral Recruitment On Reefs With Intact Fish Communities: Early Results & Hypotheses
Daniel BRUMBAUGH 1,2 , Katherine HOLMES* 1 , Robert STENECK 3 , Suzanne ARNOLD 3 ,
Douglas MCCAULEY 4 , Hillary YOUNG 5
1 Center for Biodiversity and Conservation, American Museum of Natural History, New York,
NY, 2 National MPA Center, NOAA, Santa Cruz, 3 Darling Marine Center, University of Maine,
Walpole, ME, 4 Hopkins Marine Station, Stanford University, Pacific Grove, CA, 5 Department
of Biological Sciences, Stanford University, Stanford, CA
Although coral recruitment is a key component of reef resilience, relatively little is known about
how recruitment interacts with other ecological processes that also contribute to ecosystemlevel
resilience. In particular, the types and intensities of couplings between fish communities
and coral recruitment remain particularly unclear, largely because of the limited research on
reefs with intact fish communities. To help fill this gap, we have initiated studies of recruitment
and related processes on Palmyra Atoll in the northern Line Islands of the central Pacific. Due
to its isolation and history free from substantial human populations (with the exception of
occupation during World War II), Palmyra Atoll supports fish communities that are considered
to be relatively intact and pristine. Terracotta settlement tiles (n=180), situated at three locations
and three depth zones across back and forereefs around the atoll show significant spatial
heterogeneity in background levels of coral recruitment. A four-month experiment, in which
additional tiles (n=66) were placed inside cages that excluded large fish, showed a transient
increase in recruitment on caged tiles, followed by low survivorship across all treatments.
Further observations and analysis suggest the substantial direct and indirect roles of grazing by
parrotfishes and surgeonfishes in structuring benthic communities dynamics. For example, a
grazing tolerant crustose coralline alga, Porolithon onkodes, dominates upper reef surfaces, and
the balance between Porolithon growth and grazing injury appears to influence the dynamics of
recruitment. These preliminary results illustrate some of the complex interactions between fish,
algae, and corals in early community succession in intact reef communities.
10.259
Contrasting Effects of Benthic Algae on Coral Recruits in an Upwelling Reef from the
Colombian Caribbean
Dagoberto VENERA-PONTON* 1 , Guillermo DIAZ-PULIDO 2 , Laurence MCCOOK 3 ,
Alejandro RANGEL-CAMPO 1
1 Instituto de Investigaciones Tropicales-INTROPIC, Universidad del Magdalena, Santa Marta,
Colombia, 2 Centre for Marine Studies and ARC Centre of Excellence for Coral Reef Studies,
University of Queensland, Brisbane, Australia, 3 Great Barrier Reef Marine Park Authority-
GBRMPA, Townsville, Australia
Reef degradation generally involves the replacement of hard corals cover by benthic algae. A
successful recovery of coral populations will depend on the competitive ability of corals to
settle, recruit, growth and survive on habitats dominated by benthic algae. Most studies on
coral-algal interactions and on the impacts of algae on the recovery of coral populations have
focused on the roles of algae on coral settlement and adult performance; however, there is very
little known about the effects on the survival of coral recruits, a critical step in the resilience of
coral reefs. Here we present the results of an experiment investigating 1) whether coral recruits
actually compete for space with the surrounding benthic algae; 2) the effects of benthic algae on
the growth and survival of coral recruits, and 3) the roles of algae on parrotfish predation on
coral recruits. The study used recruits of the coral Porites astreoides and was carried out in the
Tayrona National Natural Park in the Colombian Caribbean during two contrasting climatic and
oceanographic seasons (upwelling and non-upwelling). We found that the growth of recruits of
the coral P. astreoides was significantly increased when the surrounding algae were removed
while a weak algal colonization occurred when the coral recruits were damaged. These results
were consistent among the upwelling and non-upwelling seasons and constitutes an unequivocal
proof for competition between algae and coral recruits. The coral recruits were bitten by
parrotfishes only when the surrounding algae were removed and it was also consistent among
the two seasons. This suggests that benthic algae may actually protect coral recruits from
parrotfish damage. Our results illustrate the complexities of the effects of coral reef algae on the
early life history stages of corals.
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