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Marine Environment and Background Information of the Study Site Shao, Kwang-Tsao Biodiversity Research Center, Academia Sinica The underwater video capture system was installed inside the intake bay of the Third Nuclear Power Plant (NPP3) (21゜57'N; 120゜45' E) of Taiwan Power Company (Taipower). The NPP3 is located on the western side of Nanwan Bay at the southern tip of Taiwan (Figure 1) and it began to operate its first generator in 1984. Because the bay is protected by a pocket-like dyke (Figure 2), fragile coral species such as Acropora can grow very well and is less damaged by typhoons except for the strong ones. For example, in 1984, a severe tropical storm Wynne hit Nanwan directly which even caused a change of the coral reef fish assemblage afterward (Jan et al., 2001). Figure 1. Map showing the Inlet of Nanwan Bay and the study site where the video camera was installed. Inlet, site of the water intake constructed by the nuclear power plant. Outlet, outlet of the water discharge canal. Figure 2. Aerial view showing the inlet bay of the 3rd Nuclear Power Plant. More importantly, the intake area is fully protected as a no-take area where nobody can get in; only researchers can apply for permission to enter and dive on weekdays. Thus, this small (about 30,000 m2 in area) and shallow (10-15 meters in depth) bay has become the most effective MPA and coral reef fish paradise in Taiwan. This is the other reason why we chose this safe place to install the real-time wireless video camera monitoring system. In 2003, Taipower granted a joint research project to National Museum of Marine Biology & Aquarium (NMMBA), Biodiversity Research Center of Academia Sinica (BRCAS) and National Center for High-Performance Computing (NCHC) to develop this underwater video monitoring and exhibition system. All video image data were stored in NCHC and images were accessible online via Internet broadcasting. Four real-time video frames taken from four camera heads could be watched from computer or mobile devices (Jan et al., 2007) (Figure 3). Figure 3. Underwater video capture system was settled in front of one coral patch. Taipower also made a 3D film of “The Eden of Fishes” in 2014 to introduce the effect of marine protected area and the film is now screening at both the Southern Exhibition Hall of NPP3 at Houbihu and Northern Exhibition Hall of NPP3 at Wanli simultaneously. A total number of 230 species of reef fishes have been recorded after conducting the joint research project mentioned above. A guide book to introduce these coral reef fishes inside the intake bay was also published (Shao et al. 2015). Due to the shelter provided by prosperous Acropora and the continuous supply of zooplankton brought in by the cooling water, the fish assemblage here is dominant by zooplankton feeders with large aggregations of Dascyllus spp. and Chromis spp. (Figure 4). The feeding composition is rather different from other fish assemblages at the outlet area and other places in Kenting National Park where carnivores and omnivores are dominant. Figure 4. Several species of damselfishes including Chromis viridis and Dascyllus auranus hiding in the branches of Acropora coral. Nanwan Bay is located in Taiwan’s first marine park, Kenting National Park, in southern Taiwan. The Park was established in 1982 to protect the most beautiful coral reef system in Taiwan. Kenting is located at the top of The Coral Triangle which is the hot spot of marine biodiversity in the world. The total numbers of coral species and reef fish species recorded so far have reached 300 and 1154 species, respectively (Dai, 2011; Chen et al, 2010). The water temperature here is between 20-30℃, much warmer than the water temperature in northern Taiwan (15-30℃). The difference between northern and southern parts of Taiwan can reach 5℃ in the winter which creates different marine species composition in the northern and southern fish fauna. The reason for the temperature difference is that Taiwan is surrounded by three ocean currents: Kuroshio along the southern and eastern coasts all year round, South China Sea current on the western coast in summer and cold China coastal current along the west in the winter. As a result, the isothermal line of sea water temperature surrounding Taiwan is at oblique bisection, not horizontal like Tropic of Cancer (Figure 5) (Shao et al., 1999). Figure 5. Isothermal line of sea water temperature in winter season (A) and the three ocean currents around Taiwan (B). Additionally, Taiwan is located at the intersection of three Large Marine Ecosystems (or Ecogeographic Region) of East China sea, South China Sea and Philippine Sea which has the “ecotone” effect and brings different kinds of marine life from the three Regions into Taiwanese waters. Furthermore, the topography, substratum and water depth of Taiwanese territorial waters are quite diversified which give rise to various marine habitats and ecosystems. Although the total length of coastline in Taiwan is about 1100 km; 1600 km if the island of Penghu (Pescadores), Hsiao-Liu-Chiu, Green Island and Orchid Island are included; not very long compared to other marine countries, Taiwan has almost all the different kinds of marine habitats. There are coral reef, soft bottom, hard bottom, estuary, mangrove, sea grass bed, algal reef, sandy barrier lagoon, open ocean and deep sea, and even cold seep and hydrothermal vent. The high habitat diversity creates high marine biodiversity in Taiwan. According to the “Fish Database of Taiwan” (Http://fishdb.sinica.edu.tw), Taiwan possesses more than 3,100 species of fishes, about 1/10 of the world’s total, even though its total land area is only 36,000 km2 which is about 0.025% of the world’s total. Owing to the large quantities of intake cooling water discharged from the reactors, several physical parameters (e.g. water temperature, nearshore ocean currents), chemical parameters (e.g. chlorine, radionuclide, trace elements), marine organisms (e.g. phytoplankton, zooplankton, benthic invertebrates, corals and fishes) and fishery resources in the waters around NPP3 were monitored during the plant’s operation period. The National Science Committee on Problems of the Environment, Academia Sinica (SCOPE/AS) started this long-term project in 1979 (Su et al., 1989). Hung et al. (1998) summarized that the operator of the two units of NPP3 had not produced detectable effects on the marine ecosystem except the events of coral bleaching caused by the thermal discharge along the outlets of NPP3. Coral bleaching was serious in 1998 and 2007 when El Niño and La Niña affected Central Western Pacific. However, in 2007, Taiwan’s coral bleaching was not as serious compared to other neighborhood countries since there was an upwelling of cold water intruding into Nanwan Bay from outside (Lee et al., 1997). Also, the typhoons passing by southern Taiwan occasionally in the summer season can cause air and water temperature to go down and give corals a break (Fan T.Y., pers. comm.). Recent study on the pocilloporid corals from regions characterized by unstable temperatures, such as those exposed to periodic upwelling, display a remarkable degree of phenotypic plasticity (Mayfield, et al., 2013). On the contrary, the cold water intrusion which suddently lowers water temperature by up to 7-10℃ can kill some fishes if they cannot escape. Events like this happened in November 1989 and July 2008, and were reported in the newspaper. On top of water temperature changes at Kenting, anthropogenic factors also affect marine ecological environment after the National Park was established and started to attract tourists. The negative impacts come from farmland or habitat destruction along the Kenting coast and slope land to accommodate constructions such as hotels, restaurants and recreational facilities. These developments in turn led to an increase of raw sewage discharges as well as heavy sediments and suspension particles discharged directly into Nanwan Bay after rainfall. Overfishing, including on coral reef fishes, to satisfy seafood consumption of tourists is another serious problem. Both the 1st marine long-term ecological research project supported by National Science Council during 2001-2005 and a human impact monitoring project granted by National Park Authority since 2001 demonstrated this impact. The monthly nitrogen loading can be explained by the rainfall and numbers of tourists (Meng et al., 2008). Enriched water not only could cause seaweed to outgrow corals, but it could also trigger sea anemone outbreak; and this is exactly what happened during 2008-2010 in Kenting areas. Liu et al. (2009), using ECOPATH/ECOSIM, found that the interaction between overfishing and eutrophication was the main reason why the coral ecosystem degraded in the past 10 years. REFERENCES Su J.C., T.C. Hung, Y.M. Chiang, T.H. Tan, K.H. Chang, C.C. Huang, C.Y. Huang, K.T. Shao, P.P. Huang, K.T. Lee, K.L. Fan, S.Y. Yeh (1989) An ecological and environmental survey on the waters adjacent to the southern nuclear power plant. SCOPE/ROC, Academia Sinica 70: 238 pp. Lee H.J., S.Y. Chao, K.L. Fan, Y.H. Wang, N.K. Ling (1997) Tidallly induced uwelling in a semi-enclosed basin: Nanwan Bay. Continental Shelf Research, 19:671-690. Hung, T.C., C.C. Huang and K.T. Shao (1998) Ecological survey of coastal water adjacent to nuclear power plants in Taiwan. Chemistry and Ecology, 15: 129-142. Shao, K.T., J.P. Chen, S.C. Wang (1999) Biogeography and Database of Marine Fishes in Taiwan Waters. Soc. Fr. Ichtyol.pp:673-680. Jan, R.Q., J.P. Chen, C.Y. Lin and K.T. Shao (2001) Long-term monitoring of the coral reef fishes communities around a nuclear power plant. Aquatic Ecology. 35:233-243. Jan, R. Q., Y. T. Shao, F. P. Lin, T. Y. Fan, Y. Y. Tu, H. S. Tsai, K. T. Shao (2007) An underwater camera system for real-time coral reef fish monitoring. Raffl. Bull. Zool. Supplement No. 14: 273-279 Meng P.J., H.J Lee, J.T. Wang, C.C. Chen, H.J. Lin, K.S. Tew and W.J. Hsieh (2008) A long-term survey on anthropogenic impacts to the water quality of coral reefs, southern Taiwan. Environmental Pollution 156(1):67-75. Liu, P. J., K. T. Shao, R. Q. Jan, T. Y. Fan, S. L. Wong, J. S. Hwang, J. P. Chen, C. C. Chen and H. J. Lin* (2009) A trophic model of fringing coral reefs in Nanwan Bay, southern Taiwan suggests overfishing. Marine Environmental Research 68 (2009) 106–117. Chen JP, KT Shao, RQ Jan, JW Kuo, JY Chen (2010) Marine Fishes in Kenting National Park (First Revised Edition). 649pp. Kenting National Park Administration. Dai CF (2011) Eco-Tourism Map of Coral Reefs in Taiwan. Volume 1. 355 pp. BookZone Publishing Company. Mayfield A. B., T.-Y. Fan, C.-S. Chen (2013) Physiological acclimation to elevated temperature in a reef-building coral from an upwelling environment. Coral Reef 32:909–921 Shao, K.T., J.I. Tsai, C.I. Chen (2105) The Eden of fishes –Marine Protected Areas at the Intake Bay of the 3rd Nuclear Power Plant in Taiwan. Taipower Company. 260pp.