11th ICRS Abstract book - Nova Southeastern University

18.690
Assessment Of The Coral Reefs And Associated Fish Communities Of Vieques,
Puerto Rico
Laurie BAUER* 1 , Matthew KENDALL 1 , Charles MENZA 1 , Kimberly FOLEY 2
1 2
NOAA/CCMA Biogeography Branch, Silver Spring, MD, NOAA/CCMA
Biogeography Branch, Beaufort, NC
From the 1940s until 2003, portions of the Island of Vieques, Puerto Rico were used by
the United States Navy as an ammunition support detachment and a naval training range.
A field survey was conducted in May 2007 to characterize the hardbottom habitats,
associated fish communities, and marine debris around Vieques. An important question
was how reef community metrics differ in regions that have experienced varying degrees
of human activity during the time which the Navy controlled much of Vieques. Another
important consideration was the inherent differences in habitat structure, currents and
bathymetry between the north and south sides of the island. As such, ten strata were
developed to encompass these two criteria, and sites were randomly selected within each
stratum for a total of 75 survey locations. Fish community data were analyzed with
respect to spatial location, depth, and site-specific benthic habitat characteristics. In
addition, the fish community in Vieques was compared to similar hard-bottom
communities in the Virgin Islands and La Parguera, Puerto Rico. The results provide
natural resource managers with information on the abundance and distribution of marine
resources of Vieques and will serve as a baseline from which to monitor changes over
time. An island wide characterization of Vieques’ reefs and fish communities is timely
given the recent land transfer and potential changes in marine zoning.
18.691
Comparison Of Benthic Communities On Four Coral Reefs in The Veracruz Reef
System (Mexico).
Jason JONES 1 , Kim WITHERS 1 , John W. TUNNELL* 1
1 Texas A&M University-Corpus Christi, Corpus Christi, TX
The Veracruz Reef System consists of over 20 platform-type emergent reefs. They are
split into two groups, northern and southern, by the influence of the Río Jamapa which
contributes freshwater as well as municipal, industrial and agricultural pollutants to the
waters around the reefs. Four reefs, Anegada de Adentro and Blanquilla in the northern
group and Anegada de Afuera and Enmedio in the southern group, were characterized
using photo-transect techniques during Fall 2002. Scleractinian cover ranged from less
than 1% on the shallow reef at Anegada de Adentro in the northern group to about 13%
in the deepest areas of Anegada de Afuera in the southern group. Generally, scleractinian
cover was greatest at deeper depths, on reefs that were furthest from shore and in
southern group. Historically, coral cover on all reefs has declined dramatically since
previous surveys in the 1960s (40-50%), 1970s (17-53%) and 1980s (12-44%) when
scleractinians dominated benthic communities. Algae, particularly turf and crustose
forms, currently dominate reef benthic communities, with greater than 50% cover on all
reefs and at all depths. Numerous natural impacts (low salinity, heavy sedimentation,
diseases, winter cold fronts, hurricanes) and anthropogenic impacts (coral mining,
dredging, landfill, ship groundings overfishing, coral and shell collection, others) have in
combination undoubtedly caused much of this decline.
Poster Mini-Symposium 18: Reef Status and Trends
18.692
Patterns Of Coral Distribution in The Bay Islands (Honduras)
Pedro PORTILLO* 1 , Yolande BOUCHON-NAVARO 1 , Pierre LEGENDRE 2 , Max LOUIS 1 ,
Claude BOUCHON 1
1 Laboratoire de biologie marine, Université Antilles-Guyane, Pointe-à-Pitre, Guadeloupe,
2 Département des Sciences Biologiques, Université de Montréal, Montréal, QC, Canada
The present work explores the factors controlling or influencing the coral species distribution
on the reefs of the Bay Islands (Honduras) which belong to the Meso-American coral reef
system. For that, the distribution of coral assemblages was examined in the three Bay Islands
(Utila, Roatán and Guanaja). Presence-absence data from 41 species observed from 92 sites
were subjected to canonical analyses. Nineteen environmental descriptors were used as
explanatory variables in the analyses. They were separated into three sets: reef habitat
descriptors (depth, geomorphological characteristics of the reef sites), geographical factors
(latitude, longitude, seaward or leeward side of the islands) and anthropogenic influence
(nutrients, bacterial pollution, chemical contaminants). In a first step a variance partitioning of
the presence-absence data was conducted among the three sets of environmental descriptors.
This revealed that the geomorphological descriptors of the reefs accounted for 20% of the
variance of the data and that geographical and pollution factors had a negligible influence on the
qualitative distribution of the corals.
A canonical redundancy analysis (RDA) was then performed between the presence-absence
data and the geomorphological descriptors of the reefs. The results showed an ordination of the
coral species from shallow habitats (reef flat, lagoon) to deep or cryptic habitat (outer reef
slope, wall, steep slope). In complement, the “sites by species” table was submitted to a cluster
analysis. Groups of coral species characterizing the reefs of the Bay Islands were identified by
the calculation of Kendall coefficients of concordance and their validation by permutation tests.
This analysis revealed the existence on the reefs of the Bay Islands of three groups of coral
species significantly correlated, which corresponded to an assemblage of species of shallow
habitats, an assemblage of deep or shadowed habitats and an intermediate one.
18.693
Climate Change : A Threat For The Coral Reefs in The French West Indies
Claude BOUCHON* 1 , Pedro PORTILLO 1 , Yolande BOUCHON-NAVARO 1 , Max LOUIS 1
1 Laboratoire de biologie marine, Université Antilles-Guyane, Pointe-à-Pitre, Guadeloupe
Since 2002, a long term monitoring program has been set up in the French West Indies (FWI) in
the framework of the Global Coral Reef Monitoring Network (GCRMN). Benthic coral
communities and reef fish assemblages have been monitored twice a year on nine reef sites
located in the islands of Guadeloupe (5 sites), Martinique (2 sites) and St-Barthélemy (2 sites).
These studies revealed the existence of degradations of the coral communities resulting from
causes, which originate in the early 80’s. Nevertheless, the state of health of the studied coral
communities remained stable from 2002 to 2005, year marked by an exceptional warning of the
seawater temperature.
In 2005, seawater temperature exceeded 29°C from mid-May to mid-November, with maximum
values reaching 31°C, generating a massive bleaching of the corals. According to the reef, 50 to
80% of the coral species were affected by the phenomenon and about 50% of the coral colonies
bleached. At the end of November 2005, the observed mortality of the corals was relatively low
(maximum 7%). But a phenomenon of delayed mortality developed during 2006, with a
paroxysm in July, in spite of a return to normal seawater temperatures. The phenomenon
regressed at the end of that year. Coral mortality (Scleractinians and Hydrocorallians) was
minimal on the reef flats and shallow lagoons where corals support important variations of their
ecological conditions. Conversely, on the outer reef slopes, coral mortality fluctuated between
25 to 50%. The observed mortality was more important for coral communities impacted by
pollution than for healthy ones. On the whole, the reefs of the FWI lost about 30% of their coral
coverage in one-year time.
No noticeable consequence on the reef fish assemblages has been observed, probably due to the
fact that the reef architecture has not yet been altered.
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