11th ICRS Abstract book - Nova Southeastern University

18.662
Coral Reefs in Singapore: An Assessment Of Their Status And Recommendations
For Future Work
Jeffrey LOW* 1 , Robin NGIAM 1 , Rachel LIM 1 , Loke Ming CHOU 2
1 Biodiversity Centre, National Parks Board, Singapore, Singapore, 2 Department of
Biological Sciences, National University of Singapore, Singapore, Singapore
Singapore is a small island nation that has seen rapid economic growth since its
independence in 1965. Its economic success, however, has come at a cost to the marine
environment. More than 50% of its coral reefs have been lost to reclamation and
development, and the health of the remaining reefs subjected to sedimentation impact. In
spite of development pressures, the reefs have shown a remarkable degree of resilience
and interesting observations are still documented. For example, up to 258 (up from 200)
species of scleractinian corals were recorded in a recent review, and on-going studies on
sponges, gobies and scorpionids will undoubtedly reveal more species.
While much of the work is still conducted independently by separate research groups,
there is a trend towards co-operation and pooling of resources in the conservation of this
natural resource. Individuals, non-governmental organisations and government agencies
are developing rational, science-based programmes that attempt to balance the need for
development to sustain Singapore's economic growth with the conservation of this natural
heritage.
This paper charts the progress made in marine conservation since the 1980s, and
recommends some areas of work that future studies should focus on.
18.663
Riverine Run-Off Threaten Shallow Coral Reef On Lankayan Island, Sabah
Malaysia
Fung Chen CHUNG* 1 , Annadel Salvio CABANBAN 2
1 Reef Guardian Sdn Bhd, Sandakan, Malaysia, 2 WWF -Malaysia, Sabah, Malaysia
With climatic changes, bringing more rainfall that caused flooding on the mainland and
lead to river run-off containing sediments and pollutants outflow to shallow coral reef on
Lankayan Island. Reported here mass mortality of reef flat on Lankayan Island followed
continuous rainfall on Sandakan Sabah from 2-15 January 2007. Mean water salinity was
recorded low 25.4 ppt (SD 3.503, max 29.5 ppt, min 17.5, n = 41) compared to usual. The
water was recorded greenish to brownish. The death of the corals, sea cucumbers and
giant clams were observed after day 12.The event greatly reduced coral cover on the
shallow reef range 0.5-4m. Mean percentage of hard coral cover reduced to 33% (SD=
21, n=49, range 2-77%). Most affected was at the southern of the island in which the
Acropora sp. were the most recorded dead and Porites sp. were less affected. Observation
indicated that increasing of development along the coastline particularly involving
wetland clearing for agriculture, increasing use of chemicals and discharging of high
nutrient sewage effluents from mills will be another threat to coral reefs along the coast
in Sabah.
Poster Mini-Symposium 18: Reef Status and Trends
18.664
Algal Takeover in The Coral Reefs Of Eilat (Gulf Of Aqaba, Red Sea): A Disregarded
Sign Of Reef Degradation
Karnit BAHARTAN* 1 , Mohammad ZIBDAH 2 , Yousef AHMED 2 , Alvaro ISRAEL 3 , Avigdor
ABELSON 1
1 Zoology, Tel-Aviv University, Tel-Aviv, Israel, 2 Marine Science station, Aqaba, Jordan, 3 Israel
Ocheanographic and Limnological Research, Haifa, Israel
The decrease in coral live cover and extensive degradation of coral reefs is often paralleled by
the proliferation of macro-algae, commonly termed a "phase shift". The Eilat coral reefs in the
Gulf of Aqaba (Red Sea) serve as a prominent example of reefs that are covered by dense mats
of turf algae. Despite the proliferation and potential adverse effects of turf algae, the condition
of the Eilat reefs is controversial, with researchers disputing the exact state of health and
potential causes of degradation. The aim of the present study was to assess spatio-temporal
distribution patterns of algae in the Eilat reefs, and to examine coral-algal dynamics as a
potential indicator of reef health. The community structure of stony corals and algae was
studied at six sites along the Eilat and Aqaba coasts. Algal cover was found as a stable, nonseasonal
array of filamentous perennial species. Our observations revealed a widespread
occurrence of turf algae and algal dominancy in the Eilat reefs (up to 72%); whereas the algal
cover in Aqaba reefs was significantly lower (up to 6%). The proliferation of algae in several
locations along the Red Sea should serve as a warning sign of coral reef degradation, and
deserves further research into the exact causes as well as sound countermeasures. Nonetheless,
the negative correlation between turf and coralline algae, as well as the negative effects of turf
on corals, suggest that turf algae should be considered as an important indicator of the state of
coral reefs.
18.665
Recovery Patterns in A Mediterranean Gorgonian Following Repeated Mortality Events
Roberta CUPIDO* 1 , Silvia COCITO 1 , Andrea PEIRANO 1 , Sergio SGORBINI 1
1 Enea - Marine Environmental Research Centre, La Spezia, Italy
Repeated mortality events greatly affected a dense, well structured population of the
Mediterranean gorgonian Paramuricea clavata in concomitance with water warming in the Gulf
of La Spezia (NW Mediterranean). In 2004, after two mortality events (1999 and 2003), more
than 74% of all colonies were completely dead and about 22% showed some damage. Damaged
colonies presented a bare axis rapidly colonised by pioneering organisms. In order to estimate
the recover capability of this P. clavata population, a total of 30 damaged colonies were marked
and monitored photographically from 2005 to 2007. Digitised slide images were analysed by
image analysis software Sigmascan TM. Total Living Branch Length (TLBL) of each colony,
mean growth rate of primary branches (terminal branches), regeneration and loss of living
tissue, production of new branches were calculated. During monitoring period, because of new
mortality events, some marked colonies died and were substituted with new ones. In total we
monitored 372 primary branches. Except for loss of living tissue that was never observed, all
registered parameters showed a positive trend overtime. After two years TLBL exceeds the
initial value in all colonies. While growth rate of primary branches was high (1.7 ± 0.2 cm y-1)
if compared with literature, production of new branches was extremely variable (5-42 branches
col-1). Colonies survived to the new mortality events showed a good ability to regenerate loss
tissue, even if highly variable (between 60 and 100% of injured surface). Breakage of branches
that did not recover occurred in 90 % of the colonies. In spite of the slow growing and low
turnover of the species, P. clavata population showed high growth rate and a good ability to
regenerate tissue. These patterns of recovery represent valuable strategies to face mortality
events.
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