11th ICRS Abstract book - Nova Southeastern University

18-5
Coral Reef Habitat Around New Providence Island, Bahamas
Walter JAAP* 1 , Jennifer DUPONT 2 , Walter JAAP 1
1 Lithophyte & USF CMS, St. Petersburg, FL, 2 USF CMS, St. Petersburg, FL
In July 2006, the Academy of Natural Sciences of Philadelphia organized an expedition
to New Providence Island, Bahamas. Sampling sites were based on the Böhlke and
Chaplin’s (1968) field notes and recollections of Gordon Chaplin (participant in the
original studies). Coral species richness and cover, and reef surface rugosity were
examined at three depth zones: 1.5 to 6.1 m (1), 6.2 to 7.6 m (2), 7.7 to 15.2 m (3) at
Delaport Point (DP), Green Cay (GC), and Long Cay (LC). Greatest number of coral
species (27) was observed at DP-2 and the fewest (14) at DP-3. Rugosity was greatest at
GC-1 due to the spatial complexity of an Acropora palmata reef. Coral cover tracked
well with rugosity index (RI); GC-1 with an average RI of 1.7 had coral cover (20.56%)
superior to the other stations. Algae were the most abundant benthic cover component:
mean= 50.99 ± 25.45% (SD) for all stations; stony coral cover ranged from 0.65 to
20.56%, and the mean was 6.72 ± 6.94%. Similarity (Bray Curtis coefficient) was
greatest among GC stations and transects; weakest transect similarity occurred at DP-2.
ANOSIM two-way crossed test documented that replicate transects at sampling stations
were not different (Global R =0.066); however, site locations were different (Global R =
-0.259). SIMPER analysis documented that when the algae genera were removed from
the analysis, Acropora palmata contributed 20 to 30% of dissimilarity in setting GC-1
apart from other stations. Taxonomic Distinctness ( +) and Variation in Taxonomic
Distinctness (Lambda+) evaluations reported that + is stable and Lambda+ shows
strong variance.
18-6
The Almost Total Loss Of Acropora Palmata From The Shallow Waters Off
Barbados, West Indies, Initiated By Catastrophic Destruction Of A Major Bank-
Barrier Reef Off The Southeast Coast
Ian MACINTYRE* 1 , Peter GLYNN 2 , Marguerite TOSCANO 1
1 Paleobiology, National Museum of Natural History, Smithsonian Institution,
Washington, DC, 2 RSMAS - MBF, University of Miami, Miami, FL
The reef-building coral Acropora palmata has virtually disappeared from the shallow
waters off the coast of Barbados. Only a few individual colonies are known to exist off
the west coast. The abundance of A. palmata, which was a major reef-framework
component of both Pleistocene and Holocene Barbados reefs, started to decline between
4,500 to 3,300 years ago as a result of the catastrophic destruction of a major bank-barrier
reef off the southeast coast. This bank-barrier reef has never recovered to form reef
framework since this period of destruction, and colonies of A. palmata have continued to
disappear right up to modern times. Although the geologic loss of this coral was related
to severe storm damage, in historic times stress factors related to human activity have
brought this coral to a stage of almost total local extinction.
Oral Mini-Symposium 18: Reef Status and Trends
18-7
Recent Regional Declines In Reef Relief Within The Caribbean
Lorenzo ALVAREZ-FILIP* 1 , Jenny GILL 2 , Nicholas DULVY 3 , Andrew WATKINSON 1
1 School of Environmental Sciences, University of East Anglia, Norwich, United Kingdom,
2 School of Biological Sciences, University of East Anglia, Norwich, United Kingdom, 3 Centre
for Environment, Fisheries & Aquaculture Sciences, Lowestoft, United Kingdom
Habitat structure is a key factor influencing the abundance and diversity of organisms in all
ecosystems. In tropical reefs, corals and other sessile organisms can provide a complex
architecture that supports a wide array of species. The loss of this reef structure is therefore
likely to result in a loss of biodiversity, with perhaps rapid loss of reef specialists and indirect,
delayed consequences, for taxa with more generalist habitat preferences. Drastic declines in
coral cover have been reported across the Caribbean in recent decades, as result of human
activities, diseases outbreaks and climate change. Here we collate over 100 studies reporting
reef rugosity (using the chain method) in the Caribbean Sea between 1969 and 2006, to explore
the extent to which declines in coral cover have been mirrored by loss of reef structure, and the
potential implications for reef biodiversity. There have been substantial changes in reef rugosity
across the Caribbean throughout this time period, with studies in the 1970s reporting a wide
range of values but recent studies consistently reporting low reef rugosity. These declines in
habitat structure on reefs are likely to have very important implications for rates of change in
reef biodiversity.
18-8
Patterns Of Decline And Evidence For Resilience in Caribbean Coral Reefs
Virginia SCHUTTE* 1 , Elizabeth SELIG 2 , John BRUNO 1
1 Marine Sciences, UNC-Chapel Hill, Chapel Hill, NC, 2 Curriculum in Ecology and Marine
Sciences, UNC-Chapel Hill, Chapel Hill, NC
Coral reefs are being degraded worldwide and the Caribbean basin is generally thought to
include some of the world’s most at-risk reefs. Building on several recent studies that described
changes in Caribbean coral and macroalgal cover, we compiled and analyzed a database of
quantitative reef surveys from eight Caribbean regions using data from peer-reviewed and grey
literature and from several extensive monitoring programs. The database contains about 3,700
surveys from almost 2,000 reefs surveyed from 1971-2006. Yearly Caribbean-wide means
show a 14.6% decline in absolute coral cover from 32% in 1971 to 17.4% in 2006. Most of this
decline took place in the early 1980s. Coral cover has fluctuated between 12% and 18% since
1993, and has had an increasing trend from 2000 to 2006. There is significant variation in coral
cover between regions, however. Average regional coral cover ranged from 6.9% to 50.3% in
2005. Some regions have even had a modest increase in coral cover from 2001 to 2005. In
addition, most reefs have not undergone classic phase shifts. The majority of reefs have low
coral and macroalgal cover, and only 5.6% of all surveys reported more than 50% macroalgal
cover. Average macroalgal coverage on all reefs was only 12.9% in 2005, and ranged from a
fraction of a percent to 71.9% on individual reefs. Our database yielded a much higher estimate
of current coral cover and a much lower prevalence of phase shifts than previously reported.
This suggests that Caribbean reefs are more resilient than expected, and that recovery may still
be possible if we continue to invest in coral reef management.
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