11th ICRS Abstract book - Nova Southeastern University

18.658
“Changing Times, Changing Reefs” A 10 Year Review Of Changes On Coral Cover,
Dead Coral/algae And Community Structure in The Bloody Bay-Jackson Point
Marine Park, Little Cayman, Cayman Islands, Bwi
Croy MCCOY* 1
1 Dept. Of Environment, Cayman Islands Govt., Georgetown, Cayman Islands
We studied local (50% cover. Results from this study provided evidence for a phase shift from
a coral-dominated to an algal-dominated reef environment, an event which was probably
already in progress prior to the commencement of this study.
18.659
Baseline Assessments Of Coral Communities At Wake Atoll Before And After
Supertyphoon Ioke
Jacob ASHER* 1,2 , Susan VOGT 1,2 , Jean KENYON 1,2 , Bernardo VARGAS-ANGEL 1,2
1 The National Oceanic and Atmospheric Administration (NOAA), Pacific Islands
Fisheries Science Center, Coral Reef Ecosystem Division, Honolulu, HI, 2 Joint Institute
for Marine and Atmospheric Research, University of Hawaii, Honolulu
As part of the Pacific Reef Assessment and Monitoring Program (RAMP), the Coral Reef
Ecosystem Division of NOAA’s Pacific Islands Fisheries Science Center completed the
first comprehensive coral reef ecosystem assessment surveys of Wake Atoll in October
2005 using a combination of 19 towed-diver surveys covering 35 hectares, and 13 sitespecific
Rapid Ecological Assessment (REA) surveys covering ~0.6 hectares. In August
2006, the category 5 Supertyphoon Ioke passed directly over Wake Atoll. Surprisingly,
subsequent Pacific RAMP monitoring surveys in April/May 2007 found that the observed
underwater effects were comparatively small and site-specific. Percent cover estimates
by towed divers indicated that mean live scleractinian coral cover decreased from 32% in
2005 to 19% in 2007, and mean octocoral cover decreased from 15% in 2005 to 9% in
2007. However, there were no clear indications of large-scale coral destruction. Though
several large Porites colonies along the eastern shore appeared to have been dislodged
and toppled to depths of ~35 meters, these effects were localized to a single towed-diver
survey segment covering ~0.27 hectares. Percent cover by scleractinians and octocorals
at 12 forereef sites resurveyed in 2007 indicated a general, though statistically
nonsignificant decline in coral cover, with the largest decline (average > 37%) noted at
three sites in the northwest, north, and east compared to an average decline of 2.7% at the
remaining nine sites. An extensive, blanketing cyanobacteria bloom was observed in
2007 during both towed-diver and REA surveys completed near the harbor entrance and
at the shipwreck remains of the R.C. Stoner that was not observed in 2005. It is not
known whether the bloom was caused by the typhoon (e.g., flushing of nutrients from the
nearby harbor entrance, disturbance of shipwreck remains) or some other underlying
mechanisms.
Poster Mini-Symposium 18: Reef Status and Trends
18.660
Effects Of Sewage Effluent On Benthic Composition And Fish Assemblage in A Pacific
Tropical Lagoonal System
Lucy HARRISON* 1 , Clarissa BEARDEN 2 , Peter HOUK 2 , Michelle PADDACK 1 , Isabelle
COTE 1
1 Department of Biological Sciences, Simon Fraser University, Burnaby, BC, Canada, 2 CNMI
Division of Environmental Quality, Saipan, Northern Mariana Islands
Eutrophication can negatively impact fish and benthic community composition, yet our
understanding of the spatial extent of pollution impacts on reefs at varying distances from point
sources is not well known. We investigated the effects of sewage effluent on benthic
community composition and fish assemblage structure at sites with increasing distance from a
sewage outfall source in a tropical lagoonal environment, Tanapag Lagoon, Saipan, Northern
Mariana Islands. Data for enterococci levels in nearshore marine environments were obtained
from a 5-year monitoring database of weekly surveys provided by the Division of
Environmental Quality in Saipan. Enteroccocci levels were high near the sewage outfall and
decreased in a gradient in either direction away from this point. Data on benthic and fish
community structure were collected from nearshore lagoonal reefs at 10 sites along this gradient
in 2006. Multivariate analyses were conducted to examine whether community composition
and fish assemblage varied along this gradient, and whether this variation was correlated with
enteroccocci levels. Enterococci levels were found to be a good indicator of sewage inputs into
a system as they were detected at biologically significant levels away from the source. Sewage
was found to impact benthic community composition. Lagoonal reefs are important nursery
habitats for a number of reef fish species and may also provide refugia of bleaching for corals;
therefore it is important that terrestrial impacts upon these systems be understood. Results
presented support the use of enterococci levels to indicate the extent of marine pollution from
anthropogenic sources for coastal communities that monitor enterococci levels regularly (i.e.
those involved in the US EPA’s Beaches Environmental Assessment, Closure, and Health
Program).
18.661
Recent Coral Bleaching Around The Yaeyama Islands in The Ryukyus
Takanori SATOH* 1 , Tomoyo KOBAYASHI 1,2 , HAJIME HIROSAWA 1 , Mai YAMAMOTO 1
1 International Coral Reef Research and Monitoring Center, Ministry of the Environment,
Ishigaki, Japan, 2 IDEA Consultants, Inc, Setagaya, Japan
The Yaeyama Islands, including Ishigaki Island and Sekisei Lagoon, is said as one of the most
valuable coral reef in the world because this region grows numerous species of corals, over 360
species having been identified.
From the 1970s to the 1980s, the coral reefs of Japan suffered serious damage from outbreak of
crown-of-thorns starfish. After that time, the coral reefs gradually recoverd, but they again
suffered serious damage from coral bleaching in 1998, which was thought to be caused by an
unusual rise in the seawater temperature. At the same time, anthropogenic disturbances such as
the red-soil run-off from land development and sewage drove the coral reefs further into a
critical state. To conserve the coral reefs, various environmental factors affecting the coral reefs
have to be studied, and people fs serious challenge to this problem is required.
In order to promote Global Coral Reef Monitoring Network (GCRMN), The Ministry of the
Environment of Japan established gInternational Coral Reef Research and Monitoring
Center h in Ishigaki Island. Based on the Center, we have started monitoring to know the
present situation around coral reefs around the Yaeyama Islands. All monitoring data has been
incorporated and analyzed in a GIS for coral reef management. This monitoring revealed the
current state of the coral reefs that suffered seriously from the bleaching in 1998.
We will present recent coral bleaching after 1998, and changes in distribution and relative
abundance of corals around the Yaeyama Islands in the Ryukyus.
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