11th ICRS Abstract book - Nova Southeastern University

18.633
Northern Acehnese Coral Reef And Reef Fish Status
Edi RUDI* 1 , Yudi HERDIANA 2
1 Syiah Kuala University, Banda Aceh, Indonesia, 2 WCS Indonesia, Bogor, Indonesia
Northern Acehnese reefs, which are located in western Indonesia, are productive marine
ecosystems that are important for the economies of local communities. The catastrophic
tsunami in December 2004 affected local communities, and ways in which they utilized
marine resources. Impacts on reef resources were patchy although limited data and
information on coral reef condition before the tsunami has obviated the need for regular
long-term coral reef monitoring to assess their recovery from tsunami impacts and from
previous damage caused by destructive fishing and over fishing. The objectives of this
study were to provide reliable data and information on benthic hard corals and reef fish in
the northern Aceh region of Weh and Aceh islands. Using line intercept transects (LIT)
and underwater visual census techniques (VCT) at 21 sites around Weh Island and Aceh
Islands, we found that the mean coral reef cover in Weh Island was significantly higher
(29.98%-fair condition) compared to Aceh Islands (10.76%-poor condition). Coral reefs
at Rubiah Island, Sumur Tiga and Benteng that were protected under the management of
Panglima Laot of Sabang were in the best condition. Reef fish abundance in Weh Island
(32,505 no.ha -1 ) and biomass (748 kg.ha -1 ) were also significantly higher than in Aceh
Islands (abundance = 9,539 no.ha -1 ; biomass = 396 kg.ha -1 ). Fish species from the family
Pomacentridae (damsel fish) were highest in abundance and biomass.
18.634
Macroalgal Distribution in A Mexican Caribbean Reef System: A Habitat
Complexity Analysis
Ligia COLLADO-VIDES* 1 , Alejandra PIÑON-GIMATE 2
1 Biology, Florida International University, Miami, FL, 2 Posgrado, Universidad Nacional
Autónoma de México, Mazatlán, Sinaloa, Mexico
Coral reef systems are experiencing a drastic decline world-wide, leading to an increase
of macroalgal abundance and a decline of coral and seagrass communities. Macroalgae
are important components of coral reef and seagrass ecosystems, they play important
roles both positive and negative. Algae inhabiting coral reefs and seagrass beds have a
wide variety of forms that give different structural complexity to these habitats. In this
study we use architectural and morphological traits to describe and compare the reef and
lagoon macroalgal architectures and complexity. This study was conducted at Puerto
Morelos reef in the Mexican Caribbean. Macroalgae were sampled in a stratified random
sampling design, species were identified at the species level and several morphometirc
features were recorded at each organism. A total of 119 species of macroalgae were
found. Small size, erect highly branched and dense growth were more frequent in the reef
compared to the lagoon where larger, erect, less branched and less dense algae with
CaCO3 were found. Species found in both environments show intermediate values for the
parameters analyzed. We found that macroalgae provided different levels of complexity
at each environment; the scale of analysis was very important as these environments are
highly heterogeneous with several layers giving different scales at which each macroalgal
group affect complexity, therefore affecting organisms functioning at such scale of
complexity. The increase of fleshy macroalgae has been shown to decrease the habitat
complexity provided by coral structure, we highlight that the increase of only some
macroalgae species will result in a loss of complexity provided by other macroalgae
species affecting processes of settlement and recruitment of corals and fishes, and
possible creating a positive feedback resulting in coral mortality and reducing resilience
of the system.
Poster Mini-Symposium 18: Reef Status and Trends
18.635
Some Ecological Studies On Investigator Reef, One Of The Spratly's Islands, Of The
South China Sea.
Mohd Rajuddin MOHD KUSHAIRI* 1 , Mohd Nasir SAADON 1 , Kamarulzaman YUNUS 2
1 Universiti Industri Selangor, Malaysia, Shah Alam, Malaysia, 2 Universiti Islam Antarabangsa,
Malaysia, Kuantan, Malaysia
The first ecological survey was carried out around Investigator Reef, a harsh island that has not
been scientifically explored. In addition to a marvelous geomorphological feature it possessed,
there are rich corals inhabiting the periphery of this island. A total of 12 families of corals,
comprising of 30 genus had been recorded and a total of 79 species of coral fishes were found
inhabiting the coral reef. These observations were made within the 20m depth water zone.
These findings showed that this relatively small island supports a very rich coral reef
ecosystem.
18.636
Developing a Preliminary Index of Coral Reef Health
Jason HELYER* 1 , Lesa MENG 1 , James HELTSHE 2
1 Atlantic Ecology Division, U.S. Environmental Protection Agency, Narraganset, RI, 2 Atlantic
Ecology Division, U.S. Environmental Protection Agency, Narragansett, RI
The development of multimetric indices to communicate ecological condition to resource
managers and the public has numerous potential benefits for the management of coral reef
ecosystems. We used existing coral reef monitoring data from the Atlantic and Gulf Rapid Reef
Assessment (AGRRA) program to develop and evaluate a preliminary “Index of Coral Reef
Health” for the Greater Antilles eco-region in the Caribbean Sea. Sites were designated as high
or low impact based on predictions from “Reefs at Risk”, an on-line GIS database containing
information on human threats to coral reefs. Twelve candidate metrics were examined using a
step-wise discriminant function (alpha: 0.05) to determine which metrics were most important
in distinguishing between high and low impact sites. Three metrics, carnivorous fish density,
percent abundance of crustose coralline algae, and coral diversity, were selected by the stepwise
function, explaining 48% of the variance and resulting in a 15% error rate when compared
to human impact classifications using a cross validation-procedure with discriminant analysis.
When the index was calculated and compared to human impact classifications, the overall error
rate increased to 16%. Problems encountered using a large-scale regional database to develop
an “index of coral reef health” included natural variability of reef ecosystems over wide
geographic ranges and evaluating levels of human impact, such as fishing and diving. We
believe some of these problems will be reduced by focusing multimetric indices at smaller
geographic regions and increasing effort on designating sites based on anthropogenic impact.
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