CORDIO Status Report 2008
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enter for Marine and Fishery Studies of Syiah Kuala University, Banda Aceh 2 Wildlife Conservation Society Indonesian Program, Bogor keywords: Coral reef, reef fish, tsunami, Acehnese reef, marine protected area 79,&17.&% than on Aceh Island (9539 ha-1 and 396 kg.ha-1, % respectively). Pomacentridae (damsel fish) had the The coral reefs of northern Aceh, located in western highest abundance and biomass among fish families. Indonesia, are productive marine ecosystems that are Macro-invertebrates numbers, in particular sea important for the economies of local communities. urchins, were highest on Aceh compared to Weh The catastrophic tsunami in December 2004 affected Island, and in open access areas compared to marine local communities, and ways in which they utilized managed areas. The potential for sea urchins to marine resources, while impacts on reef resources were influence coral recruitment and coral reef recovery of patchy. Limited data and information on coral reef Aceh Islands requires further investigation. condition prior to the tsunami has highlighted the need for regular long-term coral reef monitoring to :6&1;<=.&:;6% assess reef recovery from the tsunami and from previous damage caused by destructive fishing and Northern Aceh on the Indonesian Island of Sumatra overfishing. The objectives of this study were to and the surrounding reefs in the Andaman Sea are well provide reliable data and information on scleractinian known for their extensive shallow reef flats that extend corals and reef fish in the northern Aceh region of 200–500 m from the shore. The reefs are dominated Weh and Aceh Islands. Using line intercept transects by massive species (mainly Poritidae and Faviidae) (LIT) and underwater visual census techniques at 21 intermingled by patches of branching Acropora and sites, we found that the mean coral cover in Weh Montipora in sheltered areas, and mostly branching Island was significantly higher (30.0%-fair condition) species at high-energy reefs (Brown 2005). Weh and compared to Aceh Island (10.8%-poor condition). Aceh Islands are the two main islands in northern Coral reefs at Rubiah Island, Sumur Tiga and Benteng Aceh, and also the westernmost reef areas in the that were protected under the management of Indonesian archipelago. The marine fauna and flora of Panglima Laot of Sabang were in the best condition. north-west Sumatra, including the northern Acehnese On Weh Island reef fish abundance (32,505 ha-1) and reefs, are comprised of species from the Indian Ocean biomass (748 kg.ha-1) were also significantly higher and the Pacific Ocean and make the region Obura, D.O., Tamelander, J., & Linden, O. (Eds) (2008). Ten years after bleaching - facing the consequences of climate change in the Indian Ocean.CORDIO Status Report 2008. Coastal Oceans Research and Development in the Indian Ocean/Sida-SAREC. Mombasa. http//:www.cordioea.org 151 4+>'/2%?"!!#$%!&'()*+,!&-./01!&*20&!$2!340'!$+5!60'!7&8$+5&9!:(.2'0.+!;-<$2.$9!7+5(+0&*$"!! biogeographically distinct from the eastern Indonesian tsunami (Baird et al. 2005a and b). coral reef fauna and flora. The status of reefs of Northern Aceh range from The reefs ecosystems support a local artisanal very poor to good condition, but have overall been fishery as well as a primarily pelagic commercial well documented only recently (Baird et al. 2005a and fishery. The area also has a tourism industry with b, Campbell et al. 2005, Ardiwijaya et al. 2006). Coral snorkeling and SCUBA diving and other recreational reefs of Weh Island are known to be generally in activities as the main attractions. These activities better condition than those on Aceh Island because of contribute income to coastal communities, in addition past differences in management between these two. To to farming, business, and government sectors (Baird et improve the management of these reefs and prevent al. 2005b). Although these reefs were subject to damaging, unsustainable, and illegal fishing practices substantial disturbance from the tsunami, initial from returning, investment is required to implement claims that northern Aceh reefs were destroyed or management practices and strategies that help greatly impacted by the tsunami in 2004 (Brown rehabilitate, restore and protect marine resources 2005, UNEP 2005) were unfounded (Baird et al. through programs of regular monitoring, education, 2005a and b). Nevertheless damage to coastal coastal management and establishment and communities was severe with five of thirteen villages maintenance of marine protected areas. The aim of in Weh Islands heavily affected by the earthquake and this research project was to provide reliable data and tsunami; mostly on the northern and southern coasts information on coral reef resources of northern Aceh (Baird et al. 2005b). Damaged houses, boats, fishing that will be useful for local people, scientists, tourists, gears, and loss of life paralyzed the northern Aceh and other stakeholders to evaluate the condition of the fisheries, including destructive fishing activities. reefs, make recommendations for management and be However, overfishing and destructive fishing practices used to evaluate the effectiveness of future coastal had caused serious damage and significantly degraded management. This report focuses on overall reef coral reef ecosystems in Aceh Islands prior to the condition (benthic, invertebrates and fish) while a 152 more detailed analysis of fish biomass and fishery F,,<'<36?'' implications is presented in Campbell et al. (2007). Abundance and biomass of reef fishes were recorded using Underwater Visual Census, recorded along the @A&B;<,% lines used for LIT, plus one additional transect. Data were collected at the species level and 9 size classes ,'/C2D%,+$2#% visually estimated (0 cm, 5-10cm, 10-15 cm, 15-20 Coral reef and invertebrate surveys were conducted in cm, 20-25 cm, 25-30 cm, 30-35 cm, 35-40 cm and 2006 and 2007 at 21 sites, 13 on Weh Island and 8 on >40 cm). Transect size was 5x50 m for fish >10cm and Aceh Island (comprising Beras and Nasi islands), while 2x50 m for fish <10cm. Data is presented as - coral reef fish surveys were conducted at 29 sites, 19 abundance, in number of individuals per hectare (ha 1 - on Weh and 10 on Aceh Island (Fig. 1). Sites were ), as well as biomass, in kilograms per hectare (kg.ha 1 selected to represent the reefs of the region and the ), estimated using standard length-weight types of site management, including Marine Protected relationships for fish species (FishBase 2000). Areas (consisting of Panglima Laot and Tourism Reserve) where fishing restrictions are in place, as well M%>$BK3.I,$=,"$%=,6' as areas with unrestricted fishing or open access areas, Macro-invertebrates were counted using 2 replicate 2 on both islands. 5x50 m belt transects at the two depths. Invertebrates were identified to species level and data converted to numbers per unit area (ha-1). Species diversity was ,'/C2D%&285(+E'2#% analyzed using the Shannon-Wiener index (H’) (Krebs Methods used were manta tow and Line Intercept 1989), with the following ranges used in this study: Transect (LIT) for benthic cover, under water visual H’<1 : low diversity; 1<H’<3 : medium diversity; census technique (UVC) for reef fishes, and belt H’<3 : high diversity transect for invertebrates (English et al. 1997, Hill and Wilkinson 2004). In order to obtain representative data of the reef, transects were laid at two depths at 2- ,$)$+#$+8)0%7()0D#2#% 3 m (shallow) and 6-8 m (deep). Using two-way nested analysis of variance (ANOVA) we examined the effect of time (fixed; 2 levels, 2006 EB$%-'$,,<6' and 2007) and management areas (fixed; 4 levels, Manta tows were used to obtain general descriptions Panglima Laot, Kawasan Wisata, open access Aceh of reef areas, estimating percent cover of hard coral, Islands, open access Weh Islands) on mean fish soft coral, dead coral and sand. Two divers were towed biomass and mean fish abundance. In order to along the reef edge using a boat at a constant speed of understand the variation in reef fish biomass and 2 knots, with regular stops every 2 minutes to record abundance between sites within management areas data on substrate cover. The number of tows varied (among sites) and among management areas data from between locations depending on reef and each transect (n = 6) at each site (random; 6 - 9 levels) environmental conditions. Two replicate 30 meter were nested within each management area. LIT transects were recorded at each site and depth. Significance among factors was tested at the P<0.05 Reef condition was assessed using percent cover of live levels. Biomass and abundance of reef fish were log hard coral was based on Gomez and Yap (1998): transformed prior to ANOVA analyses to improve excellent, 75-100%; good, 50-74%; fair, 25-49%; and homogeneity and normality. All analyses were poor, 0-24%. completed using SPSS v11.5. 153 )!