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11th ICRS Abstract book - Nova Southeastern University

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18.763<br />

Changes in Coral Reef Ecosystem Structure Across Environmental And Human<br />

Impact Gradients<br />

Sheila WALSH* 1 , Elizabeth DINSDALE 2 , Mary DONOVAN 3 , Robert EDWARDS 4 ,<br />

Tracey MCDOLE 2<br />

1 Scripps Institution of Oceanography, <strong>University</strong> of California, San Diego, La Jolla, CA,<br />

2 San Diego State <strong>University</strong>, San Diego, CA, 3 Marine Science Institute, <strong>University</strong> of<br />

California, Santa Barbara, Santa Barbara, CA, 4 Computer Science, San Diego State<br />

<strong>University</strong>, San Diego, CA<br />

The relative importance of environmental versus human causes for global change is<br />

strongly debated. Coral reef ecosystems have been shown to respond and adapt to<br />

environmental conditions over time and space. However, humans have been dramatically<br />

changing this adaptive landscape in recent history. We test the relative importance of and<br />

interactions between decreased sea surface temperature and enhanced productivity due to<br />

local upwelling and fishing pressure and human population density (a proxy for<br />

anthropogenic nutrients) on coral reef ecosystem structure. Dramatic decreases in coral<br />

cover concurrent with a decrease in biomass of the upper trophic levels of the fish<br />

community were found. Population density and fish catch were the best explanatory<br />

variables for this pattern in ecosystem structure. Sea surface temperature was not<br />

significant, but chlorophyll levels were marginally significant suggesting that increased<br />

productivity associated with human sewage rather than cold upwelling water is important<br />

in structuring the ecosystem. At areas of intermediate human disturbance, the fish<br />

community showed much greater changes than the benthic community, which may be<br />

due to the different time scales of response in the communities and the lack of significant<br />

change in abundance of herbivorous fish. This pattern in the herbivorous fish is not<br />

evidence for a trophic cascade as a result of the dramatic decline in predatory fish. Our<br />

results show strong effects on ecosystem structure due to moderate human impacts.<br />

Human induced changes in environmental conditions of similar magnitude to natural<br />

conditions elsewhere may have important impacts due to a lack of adaptation or<br />

synergistic effects with other human impacts, such as fishing.<br />

18.764<br />

A Coral Reef Monitoring Experience: Joining Community And Scientific<br />

Participation.<br />

Ana Lidia GASPAR* 1 , Beatrice FERREIRA 2 , Mauro MAIDA 2 , Caroline FEITOSA 2 ,<br />

Sergio REZENDE 2 , Eduardo MACEDO 2 , Fabio NEGRAO 3 , Ana Paula PRATES 4 ,<br />

Andreza PACHECO 2 , Iara SOMMER 5 , Liana MENDES 6 , Joao Marcello CAMARGO 1 ,<br />

Bernadete BARBOSA 7 , Danilo MARX 8<br />

1 Instituto Recifes Costeiros, Tamandare, Brazil, 2 Oceanography Department, Federal<br />

<strong>University</strong> of Pernambuco, Recife, Brazil, 3 Instituto Recifes Costeiros, Caravelas, Brazil,<br />

4 NZCM, Ministry of Environment, Brazilia, Brazil, 5 APA Guadalupe, Tamandare, Brazil,<br />

6 UFRN, Natal, Brazil, 7 Ibama, Tamandare, Brazil, 8 Pró-mar, Tamandare, Brazil<br />

The Brazilian National Coral Reef Monitoring Program is under way since 2002, funded<br />

by the Ministry of Environment, and has covered eight reef areas located in the five<br />

major reef regions from north to south: Maracajau in the Touros-Natal region; Tamandare<br />

and Maragogi in the Pirangi-Maceió region; Itaparica in the Bahia de Todos os Santos-<br />

Camamu region; Recife de Fora in the Porto Seguro-Cabrália region and Abrolhos reef in<br />

the Abrolhos Region, plus oceanic areas of Fernando de Noronha and Atol das Rocas. As<br />

recommend by the GRCMN, long-term monitoring programs should include community<br />

monitoring as well as more detailed surveys. The Brazilian program is a low budget<br />

initiative and thus the global protocol Reef Check was adopted as a first step basis. Since<br />

trained scientists, <strong>University</strong> students, park managers, NGO personnel and diver<br />

volunteers form the Brazilian Monitoring Program team, it was possible to incorporated<br />

gathering of more detailed data while still keeping the results compatible with the Reef<br />

Check protocol. New indicators were added to the standard Reef Check categories, and<br />

fish, invertebrates and corals were recorded to the species level. These detailed data<br />

allowed to obtain results on diversity of coral and fish species by region, latitudinal<br />

differences in species abundances, and to detect effects of different management<br />

strategies along 2,000km of the coast. During 5 years, surveys were conducted in 90 sites,<br />

distributed among the regions according to local support and field facilities, from a<br />

minimum of four and a maximum of 17 sites per reef area. Monitoring effort was<br />

possible with the support of several institutions and participation of volunteers who<br />

conducted surveys and participated from field trip organization to data entering. The<br />

efforts were aligned with other initiatives such as the Campaign for Conscious Conduct at<br />

Reef Environments, local research and conservation projects.<br />

Poster Mini-Symposium 18: Reef Status and Trends<br />

18.765<br />

Differential recovery rates of selected Philippine reefs from impacts of the 1997-1998<br />

ENSO event: A decade after<br />

Miledel Christine QUIBILAN* 1 , Karen Lou FRANCISCO 2 , Rollan GERONIMO 2 , Porfirio<br />

ALINO 3<br />

1 Conservation International Philippines, Quezon City, Philippines, 2 Marine Science Institute,<br />

<strong>University</strong> of the Philippines Diliman, Quezon City, Philippines, 3 Marine Science Institute,<br />

<strong>University</strong> of the Philippines Diliman, Quezon City, Panama<br />

The 1997-1998 ENSO event leading up to a massive coral bleaching event, remains to this day,<br />

as one of the most significant disturbance that has contributed greatly to demise of coral reefs<br />

worldwide. In the Philippines, as much as 20% coral mortality was observed 6 months to a year<br />

after the event. From 1997-1999, the subsequent changes in the coral community structure was<br />

compared at the level of individual frames within transects, among transects within reefs<br />

northwest of Luzon, Palawan and offshore reefs in South China Sea and Sulu Sea. We observed<br />

significant reductions in hard coral cover and consequent increases in dead coral and algal cover<br />

as well as in the overall spatial distributions of major benthic community attributes. The<br />

observed differential responses of the reefs were attributed mainly to their relative exposure (i.e.<br />

extent and duration) to the prevailing anomalous sea surface temperatures (SSTs) and to the<br />

degree of susceptibility of coral species to thermal stress and high light conditions. A decade<br />

after the event, follow-up surveys were done from 2000-2007 to determine if reefs have indeed<br />

recovered or not. While impacts from other natural (e.g. COTS infestation, storm impacts) and<br />

human-induced (e.g. siltation and overfishing) stressors have delayed reef recovery to different<br />

degrees, the establishment and effective management of no-take areas and the successful<br />

implementation of municipal fisheries regulations outside these areas indicate a reversal of<br />

degradation trends.<br />

18.766<br />

Damage And Short-Term Recovery Of Coral Reefs After Consecutive Hurricanes in A<br />

Caribbean Island<br />

Marinés MILLET-ENCALADA* 1,2 , Lorenzo ALVAREZ-FILIP 3 , Roberto HERNÁNDEZ-<br />

LANDA 1 , Héctor REYES-BONILLA 2<br />

1 Scientific monitoring and academic vinculation, Parque Nacional Arrecifes de Cozumel,<br />

Cozumel, Mexico, 2 Marine Biology, Universidad Autónoma de Baja California Sur, Baja<br />

California Sur, Mexico, 3 School of Environmental Sciences, <strong>University</strong> of East Anglia,<br />

Norwich, United Kingdom<br />

In tropical ecosystems hurricanes are important factors that shape their structure and<br />

functioning. During 2005, Cozumel Island suffered the impact of two strong hurricanes. We<br />

took this opportunity to study the immediate damage and short term (2 yr) recovery of the coral<br />

reefs affected by these consecutive disturbances in the Cozumel Reefs National Park. From<br />

2004 to 2007 we surveyed six reefs twice a year (spring and fall) performing 36 point intercept<br />

transects in a 30 m long transect for benthic components and 48 transect band (30 m long 2 m<br />

wide) for fish. Our results show that the amount of bare rock on reefs increased greatly postimpact,<br />

as a result of the loss of benthic organisms. In terms of the biotic communities, the total<br />

algae cover decreased by 28 % while the coral cover declined 55 % after the hurricanes.<br />

Physical damage to corals was patchy and most of the damage occurred to fragile species. The<br />

recovery trends indicate that the macroalgae were the benthic component with the most rapid<br />

colonization rates. Coral and massive sponges showed slow rates of recovery, while encrusting<br />

sponges exhibited a slight decrease in the last year. The abundance of grazing fishes<br />

(Acanthuridae and Scaridae) increased after the impacts suggesting that this group maintained<br />

low levels of filamentous algae in the reefs. In conclusion, after two years we found evidence of<br />

recovery and an increase in live coral tissue. The Marine Park protection and the decrease in<br />

tourist pressure may have facilitated this recovery, however it is important to notice that if the<br />

high growth rates of macroalgae continue, as they have up to now, coral recuperation might be<br />

compromised in the future.<br />

454

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