11th ICRS Abstract book - Nova Southeastern University

Poster Mini-Symposium 4: Coral Reef Organisms as Recorders of Local and Global Environmental Change
4.51
Status Of Genus Acropora in Indian Reefs And Its Role As An Indicator Of Reef
Health
Sumitro SEN* 1 , Satyanarayana CHOWDULA 2
1 Pondicherry University, Kolkata, India, 2 Zoological Survey of India, Kolkata, India
Acropora is the largest genus in order scleractinia and the major contributor to much of
the reefs in the world. There are very few contributors to the systematic status of this
genus because of its elastic phenotypic character, sensitive nature and depth varied
distribution. National and International explorations carried out in all the major reef
regions in India with the efforts of Zoological Survey of India over a decade yielded
interesting results. Qualitative studies carried out yielded about 61 valid Acropora
species out of more than 120 species listed in the world. 40 valid species are added
during the study. The quantitative studies clearly show that the diverse and extensive
reefs of India are under relentless attack by diverse anthropogenic threats especially,
because of the heavy dependence on its resources by its stake holders and also more
alarmingly due to quasi-natural threats like coral bleaching, tsunami etc. The threats
were listed in all the sites on the basis of their potentiality in that region. Statistical
analysis made with the data collected from all the major reef regions keeping Acropora as
a keystone species yielded interesting results. Extensive Acropora beds in north India
reefs which are acclaimed as the ones which probably seeded the western reefs by
renowned Acropora Biologists were totally wiped out due to sedimentation and tectonic
activity. Oceanic Atoll reefs of Lakshadweep were affected primarily due to bleaching.
Andaman reefs are affected recently due to Tsunami. Findings of the study are useful to
draw accurate management strategies for the conservation of Indian reefs. Present
diversity status of Acropora and its role in pointing out at the potentiality of the recorded
threats including site specific threats is clearly discussed in this paper with a much
needed checklist review of this genus.
4.52
The Potential Of The Soft Coral Sinularia Polydactyla And The Scleractinian Coral
Leptastrea Purpurea As Bio-Monitoring Organisms: A Case Study
Peter SCHUPP* 1 , Paulina WELCH 2 , Chie TAKASE 1 , Gary DENTON 2
1 UOG Marine Laboratory, University of Guam, Mangilao, Guam, 2 WERI, University of
Guam, Mangilao, Guam
The objective of this study was to evaluate the soft coral Sinularia polydactyla and the
scleractinian coral Leptastrea purpurea as bio-monitoring organisms for the distribution
and abundance of recalcitrant contaminants in tropical reef waters. Marine invertebrates
such as sponges, hard and soft corals are common inhabitants of barrier reef lagoons
throughout the world and show great potential as bio-monitoring organisms for aquatic
contaminants. The remarkable capacity of soft corals to accumulate polychlorinated
biphenyls (PCBs) has recently been demonstrated, making them attractive candidates as
bio-monitoring organisms. To evaluate PCB uptake and depuration kinetics in Sinularia,
we transplanted colonies from a clean site to one known to be affected by PCBs and vise
versa. In addition we investigated the effect of spawning by comparing PCB levels in
pre- and post-spawn females, intra-colonial differences between the top and the bottom of
colonies and the effect of size/age. Results will be discussed in detailed.
In another case study we examined the potential of L. purpurea larvae as test organisms
for toxicity of antifouling agents (e.g. Irgarol ® 1051) and herbicides (e.g. Roundup ®
Ready). Acute toxicity to larvae and minimum concentration of each chemical required to
adversely effect larval settlement was determined. Settlement bioassays ran for 24 h and
employed either treatment of larvae or substrate with the test chemicals. The 24-h LC50
values for Roundup, POEA (surfactant) and glyphosate (active ingredient) were 9.6
mg/L, 1.5 mg/L and 9.3 mg/L respectively. Irgarol ® 1051 reduced settlement in both
treatments at 100 mg/L, but was ineffective at lower concentrations. The minimum
experimental concentrations of Roundup, POEA and glyphosate that significantly
reduced larval settlement were 1 mg a.i./L, 10 mg/L and 3.6 mg/L respectively. The
significance of the findings is discussed with respect to levels of Irgarol ® 1051 and
Roundup ® encountered in aquatic environments elsewhere in the world.
4.53
Biogeographic Pattern And Impact Of Climate Change On Coral Communities in Taiwan
Sheng-wen HORNG* 1 , Chang-feng DAI 1
1 Institute of Oceanography, National Taiwan University, Taipei, Taiwan
Coral reefs are found in all waters around Taiwan except in the sandy areas on the west coast.
Approximately 300 scleractinian species are found in Taiwan and its offshore islets. We
explored the factors influencing or controlling Taiwan’s coral assemblages, with extensive
underwater survey. The sampled transects represented variation in sea surface temperature
(SST), substrate composition, and geography. Species data from 16 sites and 129 species were
analysed by canonical redundancy analyses. The three quantitative variables of SST, substrate
composition (percentages) and geographic coordinates were used as explanatory variables in the
canonical analyses. The first canonical axis divided the sites into reefal communities and nonreefal
communities. The second axis revealed a separation of sites by coral-dominance and
algae-dominance. Variation partitioning showed that geographic gradients accounting for 18%
of species variation was the most important factor, while sea surface temperature and substrate
composition explained 11% and 10% of species variation, respectively. The results show that
the distribution pattern of scleractinian corals in Taiwan is controlled mostly by environmental
factors reflecting a latitudinal gradient. Using the same set of scleractinian distribution data and
data from previous studies, we modeled the spatial relationship of corals with Genetic
Algorithm for Rule-set Prediction (GARP), and used it to predict the influences of climate
change on coral communities in Taiwan. Under the impact of climate change and projected rise
in SST, the spatial distribution of corals is likely to expand toward northern Taiwan, and the
species richness in these areas would increase up to 2025. However, the spatial distribution of
corals would contract with species richness in most areas decreasing dramatically beyond 2055,
resulting in the loss of coral community heterogeneity. Unbalanced changes of coral
communities can also be envisaged from the model predictions.
4.54
Deep Reef Radiocarbon Records From The Straits Of Florida
Brad ROSENHEIM* 1 , Thiago CORREA 2 , Peter SWART 2 , Gregor EBERLI 2 , Mark
GRASMUECK 2
1 Earth and Environmental Sciences, Tulane University, New Orleans, LA, 2 MGG, RSMAS,
University of Miami, Miami, FL
The deep reefs of the Straits of Florida contain a significant habitat at depths seldom explored.
A submersible exploration of the reefs in 2007 uncovered evidence of coral die-off with many
parts of the reefs consisting of both standing dead corals and dead coral rubble. The discovery
raised questions about the life cycles of these coral reefs. Are episodes of reef death part of a
natural cycle or caused by environmental factors? Is this a common state in which these reefs
are found? What are the environmental stressors that can cause such die-off? Timing the death
of these corals can yield significant information toward these questions, complimentary to the
environmental data recorded in their skeletons. We present radiocarbon ages of these coral
skeletons, both standing-dead and living, to compare the age of dissolved inorganic carbon
being incorporated into the skeletons at the time of death/collection. This information can yield
clues about timing, as well as information about water chemistry when coupled with
independent methods of dating. With other environmental proxy information archived in their
skeletons, radiocarbon records will constitute an important first step in characterizing the living
environment and life cycles of these coral reefs.
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