11th ICRS Abstract book - Nova Southeastern University

18.637
Assessment of Marginal Reef Condition at Multiple Sites Using Coral Population
Structure and Vitality
Simone OIGMAN-PSZCZOL* 1 , Joel CREED 1
1 Ecologia, Universidade do Estado do Rio de Janeiro, Rio de Janeiro, Brazil
Rapid assessments of natural systems that may be quickly degrading are needed. The
probable deterioration of a tourist region such is occurring at Armação dos Búzios,
Brazil, calls for urgent determination of versatile and efficient methods for monitoring
the state of marine benthic communities. By carrying out ecological assessments on
eleven subtidal rocky reefs, under different human pressure, this study acquired baseline
data on the percentage of cover of the stony corals and the density, colony size, partial
mortality of the scleractinian corals Mussismilia hispida and Siderastrea stellata. M.
hispida had a lower cover, lower density, greater mean colony size, more negative
skewness, higher old mortality and lower recent mortality than S. stellata. The rapid
assessment of these marginal reefs indicated that half of sites were in poor condition with
a high percentage of partial mortality of the stony corals. M. hispida showed moderate-tohigh
levels of old mortality (>30%) at more than fifty percent of the sites of the sites and
S. stellata showed high levels of recent mortality (>10%) at the majority of sites. Based
on the results found and the different life histories of these two species, populations of M.
hispida seemed to be in a critical state regarding their health and it does not seem likely
that the situation will improve in a short term. S. stellata, although better adapted to a
variable environment, also showed some evidence of mortality.
18.638
Can Patterns in Benthic Communities Be Explained By A Site Specific
Environmental Impact Index At A Marginal Reef Site in The Southwest Atlantic?
Simone OIGMAN-PSZCZOL* 1 , Joel CREED 1
1 Ecologia, Universidade do Estado do Rio de Janeiro, Rio de Janeiro, Brazil
There are many studies which assess both biological and environmental impact
approaches at once, but few analyses of biological and impact factors from multiple sites
and multiples impacts at once have been carried out. The goal of our study was to
quantify the major potential human impacts in the marine coastal zone of Búzios, Brazil;
calculate a relative environmental impact index for eleven sites; and then compare the
environmental impact index with community and population attributes. By carrying out
ecological assessments at eleven subtidal rocky shores, the percentage of cover of the
dominant benthic lifeforms; the density, colony size, partial mortality, and the associated
fauna (barnacles, crabs and bivalves) inhabiting the living tissues of the two coral
species, Mussismilia hispida and Siderastrea stellata were examined. The environment
impact assessment comprised of collecting data in the field and from secondary sources.
These data were used to generate a relative environmental impact index for each site. The
analysis of human impacts to coral communities suggested that one-third of sites in
Búzios are under high or very high proportional stress. One site (Ossos L) had the highest
human pressure. The regression analysis indicated that sites with high human pressure
had lower live cover and higher percentage of recent mortality and density of S. stellata.
The corals proved to be good indicators of habitat degradation and the species
Siderastrea stellata seemed to be the best indicator of the environmental state. The
present study has implications for current concerns about environment degradation.
Poster Mini-Symposium 18: Reef Status and Trends
18.639
The Distribution, Abundance And Volume Of The Barrel Sponge Xestospongia Muta At
Selected Sites in The Florida Keys National Marine Sanctuary
Matthew BERTIN* 1 , Michael CALLAHAN 1 , Jennifer WHEATON 1
1 Fish and Wildlife Research Institute, Saint Petersburg, Florida, Saint Petersburg, FL
In 1994, the Florida Keys Coral Reef Evaluation Monitoring Project (CREMP) was initiated to
provide status and trends data for the benthic reef resources of the Florida Keys National
Marine Sanctuary (FKNMS). Forty sampling sites were selected within the FKNMS.
Permanent station markers were installed in 1995 and annual sampling began in 1996. In 2007,
an ongoing clionid sponge survey was expanded to include the barrel sponge Xestospongia
muta in the survey at all CREMP monitoring stations.
Xestospongia muta sampling methodology was developed based on existing CREMP project
station layout. Three 1-meter-wide belt transects provide the maximum spatial coverage within
each station. A diver delineated the survey area by swimming directly above the tape holding a
meter stick perpendicular to the tape and parallel to the reef surface for a total station survey
area of approximately 66m2. The diver recorded the location and volume of each X. muta
encountered as well as notes on bleaching, disease, and scleractinian interactions. Because of
the morphological plasticity of this sponge, volume was measured by approximation to various
geometric solids (Wulff 2001).
The distribution, abundance and volume of X. muta were analyzed sanctuary-wide, regionally
and by habitat type for 103 sampling stations,. Sanctuary-wide, 89% of X. muta abundance and
93% of X. muta volume was observed at offshore deep sites. At offshore shallow and patch
sites 6% and 5% of total abundance and 5% and 2% of total volume was recorded respectively.
No X. muta was observed at any hardbottom site sanctuary-wide. At the region level, the
Middle Keys had the greatest X. muta abundance and volume, although the largest average size
of X. muta individuals was recorded in the Upper Keys.
18.640
Examination Of Algal Diviersity And Benthic Community Structure At Palmyra Atoll,
U.s. Line Islands
Cristi BRAUN* 1 , Peter VROOM 2,3
1 University of Hawai'i, Windward Community College, Kaneohe, HI, 2 Joint Institute for Marine
and Atmospheric Research, University of Hawai’i, Honolulu, HI, 3 Pacific Islands Fisheries
Science Center (PIFSC), Coral Reef Ecosystem Division (CRED), Honolulu
Palmyra Atoll National Wildlife Refuge is located 1700 kilometers southwest of the Hawaiian
Islands and is the second largest of 10 atolls under U.S. jurisdiction in the Pacific Ocean.
Relatively little is known about algal diversity or community structure at Palmyra, with the
most recent, comprehensive algal species lists dating from 1955 and 1966. As part of the
National Oceanic and Atmospheric Administration, PIFSC, Coral Reef Ecosystem Division’s
mandate, rapid ecological assessment surveys are conducted biennially to monitor reef systems
and gather baseline data for all U.S. jurisdiction Pacific reefs. In 2006, benthic cover and algal
voucher specimens were collected from 13 sites at Palmyra Atoll. Chondria, Microdictyon,
Heterosiphonia, Halimeda, and Dasya were among the 5 most common algal genera found and
were recorded from over 75% of sampled sites. Halimeda and mixed turf algal assemblages
were most prevalent in terms of benthic cover. A preliminary genus-level Cheney ratio of 15,
which is above the 6.0 “tropical threshold” indicates a tropical flora, with diversity of
Rhodophytes exceeding other algal groups. Algal diversity coupled with percent benthic cover
analyses is allowing for greater understanding of overall algal community structure in this
remote, protected ecosystem. The compilation of a comprehensive algal taxa list as baseline
data will enable future studies to monitor algal community health, detect ecosystem change, and
identify possible invasive exotics for management of this remote ecosystem.
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