11th ICRS Abstract book - Nova Southeastern University

Poster Mini-Symposium 10: Ecological Processes on Today's Reef Ecosystems
10.363
Experimental Assess Of Macroalgae Overgrowth On A Species Of Pocillopora
(Antozoa) In A Mexican Tropical Pacific Locality
Norma CORADO NAVA* 1 , Dení RODRÍGUEZ 2
1 Biología Comparada, Universidad Nacional Autónoma de México, México, D.F.,
Mexico, 2 Biologia Comparada, Universidad Nacional Autonoma de México, México D.F,
Mexico
The coral communities’ deterioration by macroalgae overgrowth is increasingly
important around the world. Algae and corals compete for substrate and speculate that in
terms of environmental stress algae are better competitors affect coral growth,
reproduction and survival. This paper was developed in the western tropical Pacific
(Playa Las Gatas, Guerrero, Mexico) and its main objective was to assess the effect of
macroalgae assemblage produces on Pocillopora and vice versa. They took out 2
experimental treatment simulating different levels of coralline stress: a) by contact, where
branches of live coral and healthy are joined a piece of dead coral and overgrowth by an
ensemble macroalgae b) court, where coral branches injured were alive and well with a
cross section of the apical portion and on the cut surface are joined a piece of dead coral
overgrowth by a macroalgae assemblage. Controls included: a') b') with fragments of
live coral and healthy, and c) branches of live coral and healthy only injured. The
experimental setting, monitoring and sampling were doing with SCUBA equipment, and
for monitoring was used a non-destructive method for photography. Our results show that
both branches of live coral and healthy who are join by contact to the macroalgae
assemblage, and those who were injured by cut, and joined to the macroalgae assemblage
survived and continued growing, covering at least partially the macroalgae assemblage on
coral dead fragment. Indeed, several of the branches that were only injured by the apex
court, grew again without presenting macroalgae. These results suggest that while the
reefs are "healthy" will not be overgrowing by macroalgae, in spite of close contact and
independently of the surrounding environmental conditions.
10.364
Outwelling Of Detrital Matter Onto Coral Reefs And Seagrass Beds By An
Introduced Mangrove, rhizophora Mangle, in Hawai`i
Matthew LURIE* 1 , Celia SMITH 1
1 Botany, University of Hawaii at Manoa, Honolulu, HI
Coastal wetland invasions by exotic flora and fauna have the potential to greatly modify
near shore coastal ecosystems, thus threatening a variety of ecosystem processes and
many cultural practices such as subsistence fishing. Introduced mangroves in the Indo-
West Pacific region represent an invasion that is drastically altering the landscape,
replacing native wetland species, and impacting watershed dynamics. The Red
Mangrove, Rhizophora mangle, was introduced to the Hawaiian Islands in 1902 on the
Island of Moloka`i by farmers for erosion control. Since then, mangroves have rapidly
colonized low energy intertidal zones and mudflats on all the Main Hawaiian Islands.
Coastal mangroves have the potential to distribute organic matter onto adjacent coastal
zones such as coral reefs and seagrass beds through the process of outwelling. This
process has not been explored in locations where mangroves are not native. This study
identifies the nature of organic carbon and nitrogen flux originating from mangroves onto
Hawaiian near shore coastal systems and its potential to be incorporated into neighboring
food webs. Flora and fauna collected at multiple trophic levels in both mangroveinvaded
and non-invaded coastal sites are investigated using stable isotopes 13C and 15N
signatures along with mixing models. Studies that identify key ecosystem processes
occurring in mangrove stands and determine how they are influencing adjacent
ecosystems, specifically coral reefs and seagrass beds, can lead to informed adaptive
management of these integrated regions.
10.365
Fish Larval Flux in A Marine Reserve in Southern Guimaras, West Central Philippines
August SANTILLAN* 1 , Wilfredo CAMPOS 2
1 Division of Biological Sciences, University of the Philippines Visayas, Miag-ao, Philippines,
2 Division of Biological Sciences, University of the Philippines Visayas, Miag-ao, Iloilo,
Philippines
Fish larval flux rates were studied in a marine reserve in Southern Guimaras, West Central
Philippines in April and November 2003 with the use of surface and near-bottom plankton nets
(335um mesh) moored in the two major channels connecting the area with surrounding waters:
the shallow northern channel, where current direction reverses with the tides, and the deeper
central channel where water consistently flows outside of the reserve. Variation in the hourly
concentration of fish eggs and larvae in the catches corresponded closely with the tidal cycle.
Differences in concentrations between surface and bottom nets in the two channels suggest net
influx of eggs and larvae into the reserve in April, and are consistent with the use of seagrass
beds and extensive mangrove stands within the reserve as nursing areas. The taxonomic and
ontogenetic composition of the larval assemblage observed during the study is further discussed
in this context.
10.366
Deriving Conservation Strategies From Philippine Reef Fish Distributions
Cleto NAÑOLA JR.* 1,2 , Porfirio ALIÑO 2
1 Biological Sciences, University of the Philippines Mindanao, Davao, Philippines, 2 Marine
Science Institute, University of the Philippines, Quezon, Philippines
Previous nationwide reef fish distribution patterns from over 1,000 underwater fish visual
census transect have shown interesting results both in its evolutionary and ecological context.
Aside from contributing to the discussions on the likely possible mechanisms on whether the
hypotheses on the center of overlap or center of origin to address biodiversity concerns,
ecological insights can be derived to assist on the nationwide and local conservation strategies.
Also cumulative species area curves in the marine biogeographic regions in the South China
Sea, Sulu Sea, Celebes Sea, Visayan Seas, North and South Pacific Seas show the differential
reef fish diversity potentials in each region. We propose the processes involved in the
evolutionary history of reef fishes that is responsible for the formation of these sub-regions and
the major structuring forces that influence ecological conditions for these regions is derived.
The biogeoraphic regions derived from reef fish distribution provide leads to the prioritisation
of conservation areas including the marine corridors based on representativeness and the
diversity values. This provides the framework for integrating the insights that suggests the
potential diversity pool for the region vis-à-vis the local diversity potential in a local area. The
state of the reefs and their pressures (e.g. overfishing and number of fisher per fishing area and
the bleaching events) and interventions in the area (no-take MPA) provide natural experiments
to improve our understanding of these areas. In complement with our monitoring of particular
reefs sites, we show that there are various vulnerabilities and susceptibilities to these different
threats. These insights are important to level off desired outcomes with local partners so that
expectations on reef recovery and fish biomass build up are realistic and lead to proactive
actions.
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